Background: Basal cell carcinoma (BCC) of the skin is the most common human cancer. The genetic alterations underlying BCC development are only partly understood. Objectives: To investigate further the molecular genet...Background: Basal cell carcinoma (BCC) of the skin is the most common human cancer. The genetic alterations underlying BCC development are only partly understood. Objectives: To investigate further the molecular genetics of sporadic BCCs, we performed mutation analyses of 10 skin cancer-associated genes in 42 tumours. Methods: Single-strand conformational polymorphism analysis followed by DNA sequencing was used to screen for mutations in the sonic hedgehog pathway genes PTCH, SMOH, SUFUH and GLI1, in the TP53 tumour suppressor gene, and in the proto-oncogenes NRAS, KRAS, HRAS, BRAF and CTNNB1. Microsatellite markers flanking the PTCH, SUFUH and TP53 loci at 9q22, 10q24 and 17p13, respectively, were studied for loss of heterozygosity (LOH). Results: PTCH mutations were found in 28 of 42 tumours (67% ). Microsatellite analysis revealed LOH on 9q22 in 20 of 38 tumours investigated (53% ), including 14 tumours with and six tumours without PTCH mutations. SMOH mutations were identified in four of the 42 BCCs (10% ) while two tumours demonstrated mutations in SUFUH, including one missense mutation and one silent mutation. None of the BCCs showed LOH at markers flanking the SUFUH locus. Seventeen BCCs (40% ) carried TP53 mutations, with only three tumours showing evidence of biallelic TP53 inactivation. TP53 mutations were present in BCCs with and without mutations in PTCH, SMOH or SUFUH. Interestingly, 72% of the TP53 alterations were presumably ultraviolet (UV)- induced transition mutations. In contrast, only 40% of the PTCH and SMOH alterations corresponded to UV signature mutations. No mutations were identified in GLI1, NRAS, KRAS, HRAS, BRAF or CTNNB1. Conclusions: Our data confirm the importance of PTCH, SMOH and TP53 mutations in the pathogenesis of sporadic BCCs. SUFUH alterations are restricted to individual cases while the other investigated genes do not appear to be important targets for mutations in BCCs.展开更多
The oridation resistance at 1100°C of a dirationally solidified Ni3Al base alloy IC6is substantially improved by the addition of yttriurn or yttrium and silicon. The stress rupture property under 1100°C/80MP...The oridation resistance at 1100°C of a dirationally solidified Ni3Al base alloy IC6is substantially improved by the addition of yttriurn or yttrium and silicon. The stress rupture property under 1100°C/80MPa is increased by adding proper amounts of yttrium, howevef it decreases bg adding 0.3wt% silicon and 0. 1wt% yttrium at the same time, which may be attributed to the formation of a needle like phase rich in nickel and molybdenum.展开更多
River Ghataprabha, during its course through Belgaum district in Karnataka state (India), receives untreated domestic waste from Gokak town and other neighboring villages situated on the bank of the river. The prese...River Ghataprabha, during its course through Belgaum district in Karnataka state (India), receives untreated domestic waste from Gokak town and other neighboring villages situated on the bank of the river. The present study involves the application of water quality model QUAL2K to predict the water quality of this polluted segment of the river. The model was calibrated and validated for biochemical oxygen demand (BOD), dissolved oxygen (DO) and total nitrogen (TN) in pre-monsoon season. Data for calibration and validation were obtained after the field and laboratory measurements. The performance of the model was evaluated using statistics based on standard errors (SE) and mean multiplicative errors (MME). The model represented the field data quite well with some exceptions. In spite of some differences between the measured and simulated data sets at some points, the calibration and validation results are acceptable especially for the developing countries where the financial resources are often limited for frequent monitoring campaigns and higher accuracy data analysis.展开更多
Objective: To compare a combination treatment of prednisone, aspirin, folate, and progesterone with no treatment in women with idiopathic recurrentmiscarriage (IRM).Design: Matched-pair study. Setting: Academic resear...Objective: To compare a combination treatment of prednisone, aspirin, folate, and progesterone with no treatment in women with idiopathic recurrentmiscarriage (IRM).Design: Matched-pair study. Setting: Academic research institution. Subject(s): Women with a history of IRM, defined as three or more consecutive miscarriages before 20 weeks’ gestation without associated anatomic, cytogenetic, hormonal, and infectious pathologies or antiphospholipid syndrome. Intervention(s): Eighty of 210 eligible women consented to participate and were treated with prednisone (20mg/d) and progesterone (20mg/d) for the first 12 weeks of gestation, aspirin (100 mg/d) for 38 weeks of gestation, and folate (5 mg every second day) throughout their pregnancies. Fifty of 80 women became pregnant; they were compared with 52 women with IRM (matched for age and number of miscarriages), who became pregnant without treatment during the same observation period. Main Outcome Measure(s): Live birth rate, complications of pregnancy, such as preeclampsia, premature birth, and intrauterine growth restriction, and therapy- related side effects. Result(s): The overall live birth rates of the treatment and control groups were 77% (40 of 52) and 35% (18 of 52) (P = .04). The rates of first and second trimester miscarriage among the treatment and control groups were 19% (10 of 52) and 0 (0 of 52), and 63% (33 of 52) and 2% (1 of 52), respectively (P = .09 and P = 1.0, respectively). The median gestational age at birth and median birth weight did not differ between the groups. We observed two and three cases of premature birth among the treatment and control groups, respectively (P = .3) and no cases of intrauterine growth restriction and Cushing’s disease. Of 80 women who started treatment, one woman had an ectopic pregnancy and one woman terminated her pregnancy due to fetal chromosome aberration (trisomy 18). Three women stopped treatment due to nausea, depression, and tachycardia. Conclusion(s): A combination treatment of prednisone, aspirin, fola展开更多
Soperplastic tensions on an IM SiCp/2024Al composite were conducted. The microstrvcture and fmcture sudece of the composite under the optimum saperplastic deformation condition were examined. The eoperimental results ...Soperplastic tensions on an IM SiCp/2024Al composite were conducted. The microstrvcture and fmcture sudece of the composite under the optimum saperplastic deformation condition were examined. The eoperimental results show that as the increase of strain during superpldstic deformation, grains fundarnentally remained equiaxed structure, and dislocation density increases gradually and its structure changes hem intererossed into nets each other to tangled and cellular structure,and the amount of liquid phase at the intedeces or gruin boundaries increases gradually. Mcrostructure examination revealed that failure took place by damage accumulation of the pmpressive decohesion of the SiC particle-matrix until a critical volume fruction was reached.展开更多
A statistical work has been done to collect the composition ranges of Ni-Mn-Ga alloys exhibiting different structures and martensite start temperature (M,), large magnetostrain or the co-existence of magnetic and st...A statistical work has been done to collect the composition ranges of Ni-Mn-Ga alloys exhibiting different structures and martensite start temperature (M,), large magnetostrain or the co-existence of magnetic and structural transitions. The alloys with five-layered (5M), seven-layered (7M) modulated and non-modulated (T) martensitic structures were mapped in the graph. An empirical formula has been presented to reflect the effect of elements nickel (Ni ), manganese ( Mn ) and gallium (Ga), on the martensite start temperature (M3). The martensitic structure is sensitive to the composition and the martensitic transformation temperature is most drastically affected by the Ni content. The alloys with large magnetostrain or co-existence effect of the magnetic and structural transitions were also listed in a limited area.展开更多
Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co an...Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCus martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.展开更多
To determine whether bimatoprost is hydrolyzed to its free acid after topical application in humans in vivo. Prospective, masked, and vehicle controlled. Thir ty-one eyes of 31 patients with cataracts. Beginning 7 day...To determine whether bimatoprost is hydrolyzed to its free acid after topical application in humans in vivo. Prospective, masked, and vehicle controlled. Thir ty-one eyes of 31 patients with cataracts. Beginning 7 days before scheduled ca taract surgery, one eye of each patient was treated with bimatoprost 0.03%or ve hicle once daily, with the last drop administered 2 to 12 hours before anterior chamber paracentesis before cataract surgery. In a masked fashion, aqueous humor specimens were assayed for bimatoprost and its free acid by high-pressure liqu id chromatography and mass spectrometry. Detection of the free acid of bimatopro st in aqueous humor. Aqueous humor concentrations of the free acid of bimatopros t were 22.0±7.0 nmol/l (mean ±standard error of the mean, n= 12) and 7.0±4.6 nmol/l (n=8) at 2 and 12 hours, respectively, and below the limit ofdetection af ter vehicle (n = 10). Concentrations of bimatoprost (amide) were 5.7±1.4 and 1. 1±0.4 nmol/l at 2 and 12 hours, respectively, and undetectable after vehicle. A fter topical application of bimatoprost in humans, a sufficient concentration of its free acid, a potent FPprostanoid receptor agonist, is found in the aqueous humor to account for its ability to reduce intraocular pressure.展开更多
PURPOSE: This study was designed to review our recent experience with continent ileostomies and evaluate patient outcomes. METHODS: Retrospective chart reviews and phone interviews of patients who underwent a continen...PURPOSE: This study was designed to review our recent experience with continent ileostomies and evaluate patient outcomes. METHODS: Retrospective chart reviews and phone interviews of patients who underwent a continent ileostomy operation from 1993 to 2003 at the Ochsner Clinic Foundation were performed. RESULTS: Twenty-four patients (19 females; age range, 22- 73 years) had construction of continent ileostomies (modified Kock pouch). There were no intraoperative mortalities or stoma-related deaths. The mean operating room time for primary constructionwas 3.9 ± 0.57 hours with a mean length of stay of 7 ± 2 days. The average follow-up period was 66 (range, 6- 134) months. The most common underlying indication for the construction of a continent ileostomy was ulcerative colitis (71 percent). Thirteen patients had a co-ntinent ileostomy created for conversion of a Brooke ileostomy and seven for a failed ileoanal pouch. Other indications included colonic inertia and incontinence in three patients and one patient who had failed multiple operations for Hirschsprung’s disease. A total of 28 revisions were performed in 14 patients (58 percent). Six patients requir-ed multiple procedures. Operative revisions included 12 skin level revision for stenosis, 11 operations for valve repairs, and 1 each for peristomal hernia repair, stomal relocation, and pouch repair for fistulas. Two patients had their pouches removed (Crohn’s disease and inability to manage pouch). The need for revision by 12 months was 29 percent, and the average time period before the first revision was 24 months (range, 4 days to 109 months). The overall failure rate (converted to conventional ileostomy)was only 8.3 percent. Ninety percent of the patients have continent pouches and are satisfied with their pouch function. CONCLUSIONS: Continent ileostomies continue to have a high rate of reoperations, reasonable functional results, and are a viable option for failed ileal pouch anal pouch patients. Surgeons electing to perform continent ileostomi展开更多
Background: Mutations in the parkin gene (PRKN) cause autosomal recessive early-onset Parkinson disease (EOPD). Objective: To investigate the presence of mutations in the PRKN gene in a white family with EOPD and ...Background: Mutations in the parkin gene (PRKN) cause autosomal recessive early-onset Parkinson disease (EOPD). Objective: To investigate the presence of mutations in the PRKN gene in a white family with EOPD and the genotype-phenotype correlations. Design: Twenty me mbers belonging to 3 generations of the EOPD fam ily with 4 affected subjects underwent genetic analysis. Direct genomic DNA sequ encing, semi-quantitative polymerase chain reaction, real-time quantitative po lymerase chain reaction, and reverse-transcriptase polymerase chain reaction an alyses were performed to identify the PRKN mutation. Results: Compound heterozyg ous mutations (T240M and EX 56 del) in the PRKN gene were identified in 4 patie nts with early onset (at ages 30-38 years).Although heterozygous T240M and homo zygous EX 56 del mutations in the PRKN gene have been previously described,this is, to our knowledge, the first report of these mutations in compound heterozyg otes. The phenotype of patients was that of classic autosomal recessive EOPD cha racterized by beneficial response to levodopa, relatively slow progression,and m otor complications. All heterozygous mutation carriers (T240M or EX 56 del) and a 56-year-old woman who was a compound heterozygou s mutation carrier (T240M and EX 56 del) were free of any neurological symptoms . Conclusions:Compound heterozygous mutations (T240M and EX56 del) in the PRKN gene were found to cause autosomal recessive EOPD in 4 members of a large white family. One additional member with the same mutation, who is more than 10 years older than the mean age at onset of the 4 affected individuals, had no clinical manifestation of the disease. This incomplete penetrance has implications for ge netic counseling, and it suggests that complex gene-environment interactions ma y play a role in the pathogenesis of PRKN EOPD.展开更多
Objective: To determine the prevalence of Y- chromosome microdeletions in recurrent pregnancy loss (RPL) couples as compared with couples with male factor infertility and fertile couples. Design: Controlled clinical s...Objective: To determine the prevalence of Y- chromosome microdeletions in recurrent pregnancy loss (RPL) couples as compared with couples with male factor infertility and fertile couples. Design: Controlled clinical study. Setting: Andrology laboratory and RPL clinic. Patient(s): Seventeen men from RPL couples, 18 men from couples with a live birth and no history of miscarriages, and 10 men from couples with male factor infertility. Intervention(s): Buccal smears for Y- chromosome microdeletion testing. Main Outcome Measure(s): The DNA was tested for microdeletions in the proximal AZFc region by polymerase chain reaction (PCR). Result(s): Fourteen of the 17 men (82% ) tested had microdeletions in one or more of the four segments studied. Two of the 10 male factor infertility patients (20% ) had microdeletions in 2 different segments. None of the 18 fertile men had any microdeletions in the 4 segments of the proximal AZFc region studied. Conclusion(s): The prevalence of the Y- chromosome microdeletions in the proximal AZFc region was much higher in men from RPL couples than from fertile or infertile couples. Although these patients are from a tertiary referral center that may skew the population and findings, one may consider Y- chromosome microdeletion testing particularly of the AZFc region in the evaluation of RPL couples when all other tests fail to reveal the etiology.展开更多
Objective: Genetic as well as hormonal factors are known to influence the development and clinical course of endometriosis. We aimed to investigate the association among 10 single nucleotide polymorphisms (SNPs) invol...Objective: Genetic as well as hormonal factors are known to influence the development and clinical course of endometriosis. We aimed to investigate the association among 10 single nucleotide polymorphisms (SNPs) involved in the estrogen metabolism and endometriosis and to develop a multiple genetic model. METHODS: In a case-control study, we investigated the genotype frequencies of 10 estrogen metabolizing SNPs in 32 patients with endometriosis and 790 healthy controls using sequencing-on-chip-technology with solid-phase polymerase chain reaction on oligonucleotide microarrays: catechol-O-methy-ltransferase, Val158Met G->A, 17-β-hydroxysteroid dehydrogenase type 1 (HSD17), vIV A->C, cytochrome P450 (CYP), 17 A2 allele T->C, CYP1A1 Mspl RFLP T->C, CYP1A1 Ile462ValA->G, CYP19 Arg264-Cys C->T, CYP19 C1558T C->T, CYP 1B1 Leu432Val, CYP1B1 Asn453Ser, and estrogen receptor alpha. IVS1-401>C. Associations and 2-way interaction models between SNPs were calculated by stepwise logistic regression models. RESULTS: In a univariate model, HSD17 vIV A->C was associated with a significantly increased risk of endometriosis (P = .004; odds ratio 3.9, 95%confidence interval 1.6-9.8). When all 2-way interactions of investigated SNPs were ascertained, no significant interactions among SNPs were observed. In a multivariate model, HSD17 vIV A->C was also significantly associated with endometriosis (P = .002). CONCLUSION: We present data on multiple SNPs in patients with endometriosis indicating an association between HSD17 gene variation and the disease. Although not able to demonstrate interaction models of SNPs, we provide evidence of HSD17 vIV A->C as a low penetrance genetic marker of endometriosis.展开更多
To test the hypothesis that the folli cle -stimulating hor-mone(FSH)threshold in patients with elevated FSH levels in the early follicular phase(EFP)is higher than in con-trols.Pilot study.Academic hospital.Six patien...To test the hypothesis that the folli cle -stimulating hor-mone(FSH)threshold in patients with elevated FSH levels in the early follicular phase(EFP)is higher than in con-trols.Pilot study.Academic hospital.Six patients with elevated EFP FSH(>10IU /L)and 13controls.Treat-ment with a GnRH agonist in the midlut eal phase before IV administration of recombinant FSH w as started in an ul-tra -low -dose step -up protocol.The FSH threshold was determined by the mean of FSH levels o f the above threshold value and the below thresh old value.Follicle -stimulating hormone threshold,FSH screening value,E 2,number of follicles.The FSH threshold in the elevated EFP FSH group was 6.75IU /L and was significantly higher than the FSH threshold of the controls(4.65IU /L).The FSH screening value on day 3was 12.0I U /L in the pa-tient group and 5.0IU /L in the contro ls.Estradiolwas significantly lower on the day that t he largest follicle was 18mm in the elevated EFP FSH group compared with controls(277vs.491pmol /L,respectively)-.On the day of hCG administration,the number of sm aller(10-13mm)follicles was equal but the number of larger(>14mm)follicles was higher in the control g roup compared with the elevated FSH group.In the contro l group,the basal FSH levels correlated highly with th e FSH threshold levels(r =0.8),but in the patients with elevated EFP FSH this correlation was absent.In normal wo men,basal FSH day 3values represent the ovarian thresh old for FSH.In womenwith elevated day 3FSH,the FSH threshold is higher but not as high as basal FSH values.We postulate that the FSH threshold in patients with elevated EFP FSH is higher be-cause of intraovarian factors.Basa l FSH overshoots the threshold,probably because of the l imited feedback by the ovary.展开更多
Objective: Several studies implicate elevated homocysteine as a risk factor for dementia and cognitive decline, but most studies have involved subjects older than 55 years from homogeneous populations. The authors exa...Objective: Several studies implicate elevated homocysteine as a risk factor for dementia and cognitive decline, but most studies have involved subjects older than 55 years from homogeneous populations. The authors examined homocysteine and cognition in a tri ethnic community sample 40 years and older. Method: The Northern Manhattan Study includes 3,298 stroke free subjects. Of these 2,871 had baseline fasting total homocysteine (tHcy) levels and Mini Mental State Examination (MMSE) scores available. The authors used multiple linear regression to examine the cross sectional association between baseline tHcy levels and mean MMSE scores adjusting for sociodemographic and vascular risk factors. Results: Homocysteine levels were related to age, renal function, and B12 deficiency. Those with B12 deficiency had tHcy levels five points higher (9.4 vs 14.4 nmol/L). Mean MMSE scores differed by age, sex, and race ethnic group. Those with hypertension, dia betes, cardiac disease, and B12 deficiency had lower MMSE scores. In multivariate analyses, elevated tHcy was associated with lower mean MMSE scores for those older than 65 but not for those 40 to 64. Adjusting for B12 deficiency and sociodemographic factors the mean MMSE was 2.2 points lower for each unit increase in the log tHcy level (95% CI 3.6, 0.9). Adding vascular risk factors to the model did not attenuate this effect (mean MMSE - 2.2 points; 95% CI - 3.5, - 0.9). Conclusions: Elevated homocysteine was independently associated with decreased cognition in subjects older than 65 in this tri ethnic cohort, adjusting for sociodemographic and vascular risk factors.展开更多
Objective: To assess the prevalence of recurrence of macular geographic atroph y (GA) of the retinal pigment epithelium (RPE) after macular translocation with 360°retinectomy (MT360) in one institution. Methods: ...Objective: To assess the prevalence of recurrence of macular geographic atroph y (GA) of the retinal pigment epithelium (RPE) after macular translocation with 360°retinectomy (MT360) in one institution. Methods: A retrospective review of all cases of GA that were treated with MT360 in 1 institution. Demographic and c linical data including the duration of preoperative visual loss, preoperative an d postoperative visual acuity, and the prevalence of postoperative foveal RPE at rophy were recorded for these patients, and these data were compared with simila r data from patients who underwent MT360 for neovascular age-related macular degeneration (AMD) as part of the prospective Duke Macula r Translocation Study, Duke University Eye Center, Durham, NC. Results: Four eye s in 4 patients with GA secondary to AMD underwent MT360 and were compared with 63 eyes in 63 patients who underwent MT360 for neovascular AMD as part of the Du ke Macular Translocation Study. The mean duration of preoperative visual loss wa s higher in the GA group (11.3 months) than in the neovascular AMD group (1.7 mo nths) (P=.08). The prevalence of postoperative foveal RPE atrophy was significan tly higher in theGAgroup (n=3; 75.0%) than in the neovascularAMDgroup (n=5; 8.3 %) (P< .01); in the GA group, this corresponded to recurrence of the GA lesions . In contrast, the postoperative RPE atrophy seen in the neovascularAMD group wa s due to postoperative mechanical forces such as laser therapy or RPE tearing. T here was no significant difference in the mean preoperative or postoperative vis ual acuity in either group. Conclusions: Subfoveal RPE atrophy can reoccur follo wing MT360 in eyes with nonneovascularAMDandGA; RPE atrophy similar to this has not been found in a large consecutive series of patients with neovascular AMD af ter MT360. Further research is needed to assess if the potential for visual reco very in eyes with endstage nonneovascular AMD is outweighed by the possibility o f postoperative recurrence of GA.展开更多
In general, it is important to operate the; airgap length uniformly for improving the system efficiency independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LI...In general, it is important to operate the; airgap length uniformly for improving the system efficiency independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LIM). And it is possible to operate the LIM propulsion system efficiently without a change of the LIM capacity through the airgap length control on the sloped rail. So, in this research, the authors introduce an airgap control system to control the airgap length which depends on the flatness of the secondary reaction plate when the LIM is operated, and design a rotary small-scaled LIM and its airgap control system before manufacturing the real system. Then, the authors analyze some characteristics of the LIM (thrust and normal force, input current, efficiency and power factor), and through the LIM control modeling, the authors finally analyze an effect of the airgap-length control of the LIM by the airgap control system.展开更多
文摘Background: Basal cell carcinoma (BCC) of the skin is the most common human cancer. The genetic alterations underlying BCC development are only partly understood. Objectives: To investigate further the molecular genetics of sporadic BCCs, we performed mutation analyses of 10 skin cancer-associated genes in 42 tumours. Methods: Single-strand conformational polymorphism analysis followed by DNA sequencing was used to screen for mutations in the sonic hedgehog pathway genes PTCH, SMOH, SUFUH and GLI1, in the TP53 tumour suppressor gene, and in the proto-oncogenes NRAS, KRAS, HRAS, BRAF and CTNNB1. Microsatellite markers flanking the PTCH, SUFUH and TP53 loci at 9q22, 10q24 and 17p13, respectively, were studied for loss of heterozygosity (LOH). Results: PTCH mutations were found in 28 of 42 tumours (67% ). Microsatellite analysis revealed LOH on 9q22 in 20 of 38 tumours investigated (53% ), including 14 tumours with and six tumours without PTCH mutations. SMOH mutations were identified in four of the 42 BCCs (10% ) while two tumours demonstrated mutations in SUFUH, including one missense mutation and one silent mutation. None of the BCCs showed LOH at markers flanking the SUFUH locus. Seventeen BCCs (40% ) carried TP53 mutations, with only three tumours showing evidence of biallelic TP53 inactivation. TP53 mutations were present in BCCs with and without mutations in PTCH, SMOH or SUFUH. Interestingly, 72% of the TP53 alterations were presumably ultraviolet (UV)- induced transition mutations. In contrast, only 40% of the PTCH and SMOH alterations corresponded to UV signature mutations. No mutations were identified in GLI1, NRAS, KRAS, HRAS, BRAF or CTNNB1. Conclusions: Our data confirm the importance of PTCH, SMOH and TP53 mutations in the pathogenesis of sporadic BCCs. SUFUH alterations are restricted to individual cases while the other investigated genes do not appear to be important targets for mutations in BCCs.
文摘The oridation resistance at 1100°C of a dirationally solidified Ni3Al base alloy IC6is substantially improved by the addition of yttriurn or yttrium and silicon. The stress rupture property under 1100°C/80MPa is increased by adding proper amounts of yttrium, howevef it decreases bg adding 0.3wt% silicon and 0. 1wt% yttrium at the same time, which may be attributed to the formation of a needle like phase rich in nickel and molybdenum.
文摘River Ghataprabha, during its course through Belgaum district in Karnataka state (India), receives untreated domestic waste from Gokak town and other neighboring villages situated on the bank of the river. The present study involves the application of water quality model QUAL2K to predict the water quality of this polluted segment of the river. The model was calibrated and validated for biochemical oxygen demand (BOD), dissolved oxygen (DO) and total nitrogen (TN) in pre-monsoon season. Data for calibration and validation were obtained after the field and laboratory measurements. The performance of the model was evaluated using statistics based on standard errors (SE) and mean multiplicative errors (MME). The model represented the field data quite well with some exceptions. In spite of some differences between the measured and simulated data sets at some points, the calibration and validation results are acceptable especially for the developing countries where the financial resources are often limited for frequent monitoring campaigns and higher accuracy data analysis.
文摘Objective: To compare a combination treatment of prednisone, aspirin, folate, and progesterone with no treatment in women with idiopathic recurrentmiscarriage (IRM).Design: Matched-pair study. Setting: Academic research institution. Subject(s): Women with a history of IRM, defined as three or more consecutive miscarriages before 20 weeks’ gestation without associated anatomic, cytogenetic, hormonal, and infectious pathologies or antiphospholipid syndrome. Intervention(s): Eighty of 210 eligible women consented to participate and were treated with prednisone (20mg/d) and progesterone (20mg/d) for the first 12 weeks of gestation, aspirin (100 mg/d) for 38 weeks of gestation, and folate (5 mg every second day) throughout their pregnancies. Fifty of 80 women became pregnant; they were compared with 52 women with IRM (matched for age and number of miscarriages), who became pregnant without treatment during the same observation period. Main Outcome Measure(s): Live birth rate, complications of pregnancy, such as preeclampsia, premature birth, and intrauterine growth restriction, and therapy- related side effects. Result(s): The overall live birth rates of the treatment and control groups were 77% (40 of 52) and 35% (18 of 52) (P = .04). The rates of first and second trimester miscarriage among the treatment and control groups were 19% (10 of 52) and 0 (0 of 52), and 63% (33 of 52) and 2% (1 of 52), respectively (P = .09 and P = 1.0, respectively). The median gestational age at birth and median birth weight did not differ between the groups. We observed two and three cases of premature birth among the treatment and control groups, respectively (P = .3) and no cases of intrauterine growth restriction and Cushing’s disease. Of 80 women who started treatment, one woman had an ectopic pregnancy and one woman terminated her pregnancy due to fetal chromosome aberration (trisomy 18). Three women stopped treatment due to nausea, depression, and tachycardia. Conclusion(s): A combination treatment of prednisone, aspirin, fola
文摘Soperplastic tensions on an IM SiCp/2024Al composite were conducted. The microstrvcture and fmcture sudece of the composite under the optimum saperplastic deformation condition were examined. The eoperimental results show that as the increase of strain during superpldstic deformation, grains fundarnentally remained equiaxed structure, and dislocation density increases gradually and its structure changes hem intererossed into nets each other to tangled and cellular structure,and the amount of liquid phase at the intedeces or gruin boundaries increases gradually. Mcrostructure examination revealed that failure took place by damage accumulation of the pmpressive decohesion of the SiC particle-matrix until a critical volume fruction was reached.
基金the National Natural Science Foundation of China (No. 50271002) New Century Program for Excellent Talents of Ministry of Education of China (No. 04-0165).
文摘A statistical work has been done to collect the composition ranges of Ni-Mn-Ga alloys exhibiting different structures and martensite start temperature (M,), large magnetostrain or the co-existence of magnetic and structural transitions. The alloys with five-layered (5M), seven-layered (7M) modulated and non-modulated (T) martensitic structures were mapped in the graph. An empirical formula has been presented to reflect the effect of elements nickel (Ni ), manganese ( Mn ) and gallium (Ga), on the martensite start temperature (M3). The martensitic structure is sensitive to the composition and the martensitic transformation temperature is most drastically affected by the Ni content. The alloys with large magnetostrain or co-existence effect of the magnetic and structural transitions were also listed in a limited area.
基金supported by the National Natural Science Foundation of China(No.20271002)Aviation Science Foundation of China(No.00G51007).
文摘Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCus martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.
文摘To determine whether bimatoprost is hydrolyzed to its free acid after topical application in humans in vivo. Prospective, masked, and vehicle controlled. Thir ty-one eyes of 31 patients with cataracts. Beginning 7 days before scheduled ca taract surgery, one eye of each patient was treated with bimatoprost 0.03%or ve hicle once daily, with the last drop administered 2 to 12 hours before anterior chamber paracentesis before cataract surgery. In a masked fashion, aqueous humor specimens were assayed for bimatoprost and its free acid by high-pressure liqu id chromatography and mass spectrometry. Detection of the free acid of bimatopro st in aqueous humor. Aqueous humor concentrations of the free acid of bimatopros t were 22.0±7.0 nmol/l (mean ±standard error of the mean, n= 12) and 7.0±4.6 nmol/l (n=8) at 2 and 12 hours, respectively, and below the limit ofdetection af ter vehicle (n = 10). Concentrations of bimatoprost (amide) were 5.7±1.4 and 1. 1±0.4 nmol/l at 2 and 12 hours, respectively, and undetectable after vehicle. A fter topical application of bimatoprost in humans, a sufficient concentration of its free acid, a potent FPprostanoid receptor agonist, is found in the aqueous humor to account for its ability to reduce intraocular pressure.
文摘PURPOSE: This study was designed to review our recent experience with continent ileostomies and evaluate patient outcomes. METHODS: Retrospective chart reviews and phone interviews of patients who underwent a continent ileostomy operation from 1993 to 2003 at the Ochsner Clinic Foundation were performed. RESULTS: Twenty-four patients (19 females; age range, 22- 73 years) had construction of continent ileostomies (modified Kock pouch). There were no intraoperative mortalities or stoma-related deaths. The mean operating room time for primary constructionwas 3.9 ± 0.57 hours with a mean length of stay of 7 ± 2 days. The average follow-up period was 66 (range, 6- 134) months. The most common underlying indication for the construction of a continent ileostomy was ulcerative colitis (71 percent). Thirteen patients had a co-ntinent ileostomy created for conversion of a Brooke ileostomy and seven for a failed ileoanal pouch. Other indications included colonic inertia and incontinence in three patients and one patient who had failed multiple operations for Hirschsprung’s disease. A total of 28 revisions were performed in 14 patients (58 percent). Six patients requir-ed multiple procedures. Operative revisions included 12 skin level revision for stenosis, 11 operations for valve repairs, and 1 each for peristomal hernia repair, stomal relocation, and pouch repair for fistulas. Two patients had their pouches removed (Crohn’s disease and inability to manage pouch). The need for revision by 12 months was 29 percent, and the average time period before the first revision was 24 months (range, 4 days to 109 months). The overall failure rate (converted to conventional ileostomy)was only 8.3 percent. Ninety percent of the patients have continent pouches and are satisfied with their pouch function. CONCLUSIONS: Continent ileostomies continue to have a high rate of reoperations, reasonable functional results, and are a viable option for failed ileal pouch anal pouch patients. Surgeons electing to perform continent ileostomi
文摘Background: Mutations in the parkin gene (PRKN) cause autosomal recessive early-onset Parkinson disease (EOPD). Objective: To investigate the presence of mutations in the PRKN gene in a white family with EOPD and the genotype-phenotype correlations. Design: Twenty me mbers belonging to 3 generations of the EOPD fam ily with 4 affected subjects underwent genetic analysis. Direct genomic DNA sequ encing, semi-quantitative polymerase chain reaction, real-time quantitative po lymerase chain reaction, and reverse-transcriptase polymerase chain reaction an alyses were performed to identify the PRKN mutation. Results: Compound heterozyg ous mutations (T240M and EX 56 del) in the PRKN gene were identified in 4 patie nts with early onset (at ages 30-38 years).Although heterozygous T240M and homo zygous EX 56 del mutations in the PRKN gene have been previously described,this is, to our knowledge, the first report of these mutations in compound heterozyg otes. The phenotype of patients was that of classic autosomal recessive EOPD cha racterized by beneficial response to levodopa, relatively slow progression,and m otor complications. All heterozygous mutation carriers (T240M or EX 56 del) and a 56-year-old woman who was a compound heterozygou s mutation carrier (T240M and EX 56 del) were free of any neurological symptoms . Conclusions:Compound heterozygous mutations (T240M and EX56 del) in the PRKN gene were found to cause autosomal recessive EOPD in 4 members of a large white family. One additional member with the same mutation, who is more than 10 years older than the mean age at onset of the 4 affected individuals, had no clinical manifestation of the disease. This incomplete penetrance has implications for ge netic counseling, and it suggests that complex gene-environment interactions ma y play a role in the pathogenesis of PRKN EOPD.
文摘Objective: To determine the prevalence of Y- chromosome microdeletions in recurrent pregnancy loss (RPL) couples as compared with couples with male factor infertility and fertile couples. Design: Controlled clinical study. Setting: Andrology laboratory and RPL clinic. Patient(s): Seventeen men from RPL couples, 18 men from couples with a live birth and no history of miscarriages, and 10 men from couples with male factor infertility. Intervention(s): Buccal smears for Y- chromosome microdeletion testing. Main Outcome Measure(s): The DNA was tested for microdeletions in the proximal AZFc region by polymerase chain reaction (PCR). Result(s): Fourteen of the 17 men (82% ) tested had microdeletions in one or more of the four segments studied. Two of the 10 male factor infertility patients (20% ) had microdeletions in 2 different segments. None of the 18 fertile men had any microdeletions in the 4 segments of the proximal AZFc region studied. Conclusion(s): The prevalence of the Y- chromosome microdeletions in the proximal AZFc region was much higher in men from RPL couples than from fertile or infertile couples. Although these patients are from a tertiary referral center that may skew the population and findings, one may consider Y- chromosome microdeletion testing particularly of the AZFc region in the evaluation of RPL couples when all other tests fail to reveal the etiology.
文摘Objective: Genetic as well as hormonal factors are known to influence the development and clinical course of endometriosis. We aimed to investigate the association among 10 single nucleotide polymorphisms (SNPs) involved in the estrogen metabolism and endometriosis and to develop a multiple genetic model. METHODS: In a case-control study, we investigated the genotype frequencies of 10 estrogen metabolizing SNPs in 32 patients with endometriosis and 790 healthy controls using sequencing-on-chip-technology with solid-phase polymerase chain reaction on oligonucleotide microarrays: catechol-O-methy-ltransferase, Val158Met G->A, 17-β-hydroxysteroid dehydrogenase type 1 (HSD17), vIV A->C, cytochrome P450 (CYP), 17 A2 allele T->C, CYP1A1 Mspl RFLP T->C, CYP1A1 Ile462ValA->G, CYP19 Arg264-Cys C->T, CYP19 C1558T C->T, CYP 1B1 Leu432Val, CYP1B1 Asn453Ser, and estrogen receptor alpha. IVS1-401>C. Associations and 2-way interaction models between SNPs were calculated by stepwise logistic regression models. RESULTS: In a univariate model, HSD17 vIV A->C was associated with a significantly increased risk of endometriosis (P = .004; odds ratio 3.9, 95%confidence interval 1.6-9.8). When all 2-way interactions of investigated SNPs were ascertained, no significant interactions among SNPs were observed. In a multivariate model, HSD17 vIV A->C was also significantly associated with endometriosis (P = .002). CONCLUSION: We present data on multiple SNPs in patients with endometriosis indicating an association between HSD17 gene variation and the disease. Although not able to demonstrate interaction models of SNPs, we provide evidence of HSD17 vIV A->C as a low penetrance genetic marker of endometriosis.
文摘To test the hypothesis that the folli cle -stimulating hor-mone(FSH)threshold in patients with elevated FSH levels in the early follicular phase(EFP)is higher than in con-trols.Pilot study.Academic hospital.Six patients with elevated EFP FSH(>10IU /L)and 13controls.Treat-ment with a GnRH agonist in the midlut eal phase before IV administration of recombinant FSH w as started in an ul-tra -low -dose step -up protocol.The FSH threshold was determined by the mean of FSH levels o f the above threshold value and the below thresh old value.Follicle -stimulating hormone threshold,FSH screening value,E 2,number of follicles.The FSH threshold in the elevated EFP FSH group was 6.75IU /L and was significantly higher than the FSH threshold of the controls(4.65IU /L).The FSH screening value on day 3was 12.0I U /L in the pa-tient group and 5.0IU /L in the contro ls.Estradiolwas significantly lower on the day that t he largest follicle was 18mm in the elevated EFP FSH group compared with controls(277vs.491pmol /L,respectively)-.On the day of hCG administration,the number of sm aller(10-13mm)follicles was equal but the number of larger(>14mm)follicles was higher in the control g roup compared with the elevated FSH group.In the contro l group,the basal FSH levels correlated highly with th e FSH threshold levels(r =0.8),but in the patients with elevated EFP FSH this correlation was absent.In normal wo men,basal FSH day 3values represent the ovarian thresh old for FSH.In womenwith elevated day 3FSH,the FSH threshold is higher but not as high as basal FSH values.We postulate that the FSH threshold in patients with elevated EFP FSH is higher be-cause of intraovarian factors.Basa l FSH overshoots the threshold,probably because of the l imited feedback by the ovary.
文摘Objective: Several studies implicate elevated homocysteine as a risk factor for dementia and cognitive decline, but most studies have involved subjects older than 55 years from homogeneous populations. The authors examined homocysteine and cognition in a tri ethnic community sample 40 years and older. Method: The Northern Manhattan Study includes 3,298 stroke free subjects. Of these 2,871 had baseline fasting total homocysteine (tHcy) levels and Mini Mental State Examination (MMSE) scores available. The authors used multiple linear regression to examine the cross sectional association between baseline tHcy levels and mean MMSE scores adjusting for sociodemographic and vascular risk factors. Results: Homocysteine levels were related to age, renal function, and B12 deficiency. Those with B12 deficiency had tHcy levels five points higher (9.4 vs 14.4 nmol/L). Mean MMSE scores differed by age, sex, and race ethnic group. Those with hypertension, dia betes, cardiac disease, and B12 deficiency had lower MMSE scores. In multivariate analyses, elevated tHcy was associated with lower mean MMSE scores for those older than 65 but not for those 40 to 64. Adjusting for B12 deficiency and sociodemographic factors the mean MMSE was 2.2 points lower for each unit increase in the log tHcy level (95% CI 3.6, 0.9). Adding vascular risk factors to the model did not attenuate this effect (mean MMSE - 2.2 points; 95% CI - 3.5, - 0.9). Conclusions: Elevated homocysteine was independently associated with decreased cognition in subjects older than 65 in this tri ethnic cohort, adjusting for sociodemographic and vascular risk factors.
文摘Objective: To assess the prevalence of recurrence of macular geographic atroph y (GA) of the retinal pigment epithelium (RPE) after macular translocation with 360°retinectomy (MT360) in one institution. Methods: A retrospective review of all cases of GA that were treated with MT360 in 1 institution. Demographic and c linical data including the duration of preoperative visual loss, preoperative an d postoperative visual acuity, and the prevalence of postoperative foveal RPE at rophy were recorded for these patients, and these data were compared with simila r data from patients who underwent MT360 for neovascular age-related macular degeneration (AMD) as part of the prospective Duke Macula r Translocation Study, Duke University Eye Center, Durham, NC. Results: Four eye s in 4 patients with GA secondary to AMD underwent MT360 and were compared with 63 eyes in 63 patients who underwent MT360 for neovascular AMD as part of the Du ke Macular Translocation Study. The mean duration of preoperative visual loss wa s higher in the GA group (11.3 months) than in the neovascular AMD group (1.7 mo nths) (P=.08). The prevalence of postoperative foveal RPE atrophy was significan tly higher in theGAgroup (n=3; 75.0%) than in the neovascularAMDgroup (n=5; 8.3 %) (P< .01); in the GA group, this corresponded to recurrence of the GA lesions . In contrast, the postoperative RPE atrophy seen in the neovascularAMD group wa s due to postoperative mechanical forces such as laser therapy or RPE tearing. T here was no significant difference in the mean preoperative or postoperative vis ual acuity in either group. Conclusions: Subfoveal RPE atrophy can reoccur follo wing MT360 in eyes with nonneovascularAMDandGA; RPE atrophy similar to this has not been found in a large consecutive series of patients with neovascular AMD af ter MT360. Further research is needed to assess if the potential for visual reco very in eyes with endstage nonneovascular AMD is outweighed by the possibility o f postoperative recurrence of GA.
文摘In general, it is important to operate the; airgap length uniformly for improving the system efficiency independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LIM). And it is possible to operate the LIM propulsion system efficiently without a change of the LIM capacity through the airgap length control on the sloped rail. So, in this research, the authors introduce an airgap control system to control the airgap length which depends on the flatness of the secondary reaction plate when the LIM is operated, and design a rotary small-scaled LIM and its airgap control system before manufacturing the real system. Then, the authors analyze some characteristics of the LIM (thrust and normal force, input current, efficiency and power factor), and through the LIM control modeling, the authors finally analyze an effect of the airgap-length control of the LIM by the airgap control system.