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利用悬浮培养进行葡萄细胞抗寒性筛选的研究 被引量:14
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作者 张明鹏 Rajashekar c.b. 《园艺学报》 CAS CSCD 北大核心 1992年第2期135-139,共5页
利用细胞悬浮培养和TTC分析法,进行葡萄细胞抗寒性筛选的研究结果表明,3个供试品种,未经低温筛选的细胞低温致死温度为-3℃左右。经过-3至-7℃人工低温分级筛选,可以筛选出低温致死温度在-5、-6和-7℃左右的抗寒细胞系。在-3至-7℃范围... 利用细胞悬浮培养和TTC分析法,进行葡萄细胞抗寒性筛选的研究结果表明,3个供试品种,未经低温筛选的细胞低温致死温度为-3℃左右。经过-3至-7℃人工低温分级筛选,可以筛选出低温致死温度在-5、-6和-7℃左右的抗寒细胞系。在-3至-7℃范围内,筛选温度越低,所获抗寒细胞系的抗寒性越强,其低温致死温度也越低。当筛选温度下降至-8℃时,3个供试品种的细胞残存量都极微,没有筛选出抗寒细胞系。 展开更多
关键词 葡萄 抗寒性 筛选 细胞悬浮培养
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散发基底细胞癌的PTCH,SMOH,SUFUH和TP53基因的体细胞突变 被引量:4
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作者 Reifenberger J. Wolter M. +1 位作者 Knobbe c.b. 刘燕 《世界核心医学期刊文摘(皮肤病学分册)》 2005年第7期5-6,共2页
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
关键词 基底细胞癌 TP53基因 体细胞突变 基因突变 肿瘤病灶 癌相关基因 遗传学改变 单链构象多态性 微卫星标记 突变分析
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IMPROVEMENT OF OXIDATION RESISTANCE AND MECHANICAL PROPERTIES BY THE ADDITION OF YTTRIUM AND SILICON IN A Ni_3Al BASE ALLOY IC6 被引量:4
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作者 c.b. Xiao and Y.F.Han(beijing Institute of Aeronautical Materials (bIAM), beijing 100095, china) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第4期296-300,共5页
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
关键词 Ni_3Al YTTRIUM SILICON oxidation resistance
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应用Datalogger System研究不同株型品种稻田小气候的特征 被引量:3
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作者 张旭 林道宣 +9 位作者 何子儒 陈钊明 孔清霓 余昭楹 邱润恒 梁祖扬 刘彦卓 Osmond c.b. Wong S.c. Terashima I. 《中国农业气象》 CSCD 北大核心 1991年第3期1-5,共5页
本文分析了由微气候“数据记录仪”(Datalogger)自动收集的资料,探讨了稻田在水稻灌浆期的小气候特征。结果表明:直立叶品种比平展叶品种在冠层以下15cm处光量子相差1倍左右;植株温度及冠层叶面温度品种间差别较小,稻田1.5m高处空气湿... 本文分析了由微气候“数据记录仪”(Datalogger)自动收集的资料,探讨了稻田在水稻灌浆期的小气候特征。结果表明:直立叶品种比平展叶品种在冠层以下15cm处光量子相差1倍左右;植株温度及冠层叶面温度品种间差别较小,稻田1.5m高处空气湿度品种间不存在差别。初步认为直立叶型品种能更充分利用光能,这是直立叶型品种产量高于水平叶型品种的重要原因。此外还对Datalogger所获得的田间气候资料可靠性进行检验、肯定。 展开更多
关键词 稻田 小气候 水稻 品种
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Application of QUAL2K for Water Quality Modeling of River Ghataprabha (India) 被引量:1
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作者 P.b. Kalburgi c.b. Shivayogimath b.K. Purandara 《Journal of Environmental Science and Engineering》 2010年第12期6-11,共6页
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
关键词 Water quality modeling QUAL2K river pollution river Ghataprabha BOD modeling DO modelling
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泼尼松、阿司匹林、叶酸及孕酮联合治疗妇女原发性反复流产:一项病例对照研究 被引量:1
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作者 Tempfer c.b. Kurz c. +1 位作者 bentz E.-K. 朱晓明 《世界核心医学期刊文摘(妇产科学分册)》 2006年第11期37-38,共2页
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
关键词 反复流产 病例对照研究 活产率 异位妊娠 妊娠过程 妊娠早期 抗磷脂综合征 妊娠初期 染色体异常
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SUPERPLASTICAL DEFORMATION AND FRACTURE MECHANISM 0F A SiC_p/2024Al COMPOSITE
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作者 Y. Yan c.b. Zhang and b.R. Liu (box 104, college of Science, Northeastern University Shenyang 110006, china) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第6期0-0,0-0+0-0+0-0,共8页
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
关键词 COMPOSITE superplastic deformation fracture mechanism
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COMPOSITION TRIANGLE DIAGRAMS OF Ni-Mn-Ga MAGNETIC SHAPE MEMORY ALLOYS 被引量:1
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作者 Y.F. Wang J.M. Wang c.b. Jiang H.b. Xu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2006年第3期171-175,共5页
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
关键词 Ni2MnGa alloy martensitic transformation magnetic shape memory alloy
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MARTENSITIC TRANSFORMATION AND THERMAL STABILITY IN Cu-Al-Co AND Cu-Al-Zr ALLOYS 被引量:1
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作者 Y.Q. Ma, c.b. Jiang and H.b. XuDepartment of Materials Science and Engineering, beijing University of Aeronautics and Astronautics, beijing 100083, china 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2003年第6期445-448,共4页
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
关键词 shape memory alloy high martensitic transformation tempera-ture Cu-based alloy thermal stability
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白内障手术前接受拜马前列素治疗的人眼房水样本中检测拜马前列素的自由酸
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作者 camras c.b. Toris c.b. +1 位作者 Sjoquist b. 张少娟 《世界核心医学期刊文摘(眼科学分册)》 2005年第3期61-62,共2页
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
关键词 白内障手术 眼房水 前房穿刺 液体色谱法 低眼压 中拜 盲法 切除术 光谱测定 局部应用
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全球对流层中层二氧化碳柱浓度数据集(2003–2015) 被引量:1
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作者 符传博 丹利 《全球变化数据学报(中英文)》 CSCD 2019年第2期149-154,215-220,共12页
人类活动导致大气中温室气体浓度上升,是全球气候变暖的重要原因之一。基于美国Aqua卫星搭载的大气红外垂直遥感器(AtmosphericInfraredSounder,AIRS)数据反演的2003–2015年全球对流层中层CO2柱浓度资料,利用地基观测结果对其进行验证... 人类活动导致大气中温室气体浓度上升,是全球气候变暖的重要原因之一。基于美国Aqua卫星搭载的大气红外垂直遥感器(AtmosphericInfraredSounder,AIRS)数据反演的2003–2015年全球对流层中层CO2柱浓度资料,利用地基观测结果对其进行验证,并对其进行时空变化进行分析,得出《全球对流层中层二氧化碳柱浓度数据集(2003–2015)》。数据结果表明:北半球30°N–60°N是CO2浓度高值带,低值中心主要出现在15°S–15°N,140°W–100°E的低纬地区。地基观测与AIRS卫星反演结果基本一致,年增长率约为1.926mL/(m3·a)。该数据集包括:(1)2003–2015年全球对流层中层CO2柱浓度;(2)全球对流层中层CO2柱浓度年平均增长率;(3)2003年1月至2015年12月地基观测与AIRS反演结果对比。该数据集存储为.xlsx和.tif格式,数据量为292 KB(压缩为1个文件,246 KB)。该数据集的分析成果发表在《地球物理学报》2018年第61卷第11期。 展开更多
关键词 CO2 卫星遥感 全球 地球物理学报
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控制式回肠造口术:目前经验 被引量:1
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作者 castillo E. Thomassie L.M. +2 位作者 Whitlow c.b. D.E. beck 赵萌 《世界核心医学期刊文摘(胃肠病学分册)》 2005年第11期19-20,共2页
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
关键词 回肠造口术 控制式 回肠袋 手术失败率 造口旁疝 先天性巨结肠 溃疡性结肠炎 囊袋 手术时间 外科医生
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复合杂合parkin基因突变家族的不同表型
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作者 Hunter c.b. J. Jankovic 邱伟庆 《世界核心医学期刊文摘(神经病学分册)》 2006年第6期17-18,共2页
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
关键词 PARKIN基因突变 表型关系 杂合 常染色体隐性遗传性 家族 复合 半定量聚合酶链反应 实时定量聚合酶链反应 PARKIN基因 基因携带者
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燃煤热电厂产生的汞在周围大气、土壤和植物中的分布及其影响 被引量:1
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作者 c.b.S Sengar D.K.Soni +1 位作者 A.L.Aggarwal 杨明凤 《煤矿环境保护》 1993年第1期61-62,共2页
煤炭是印度最重要的能源之一,在当今能源紧缺的时代煤炭显得更为重要。在印度煤炭资源极其丰富,所以绝大多数的发电厂都使用煤炭,这就导致汞和煤粉对环境的污染。如印度中部一家大型燃煤热电站,监测发现离污染源10km的周围大气中,颗粒... 煤炭是印度最重要的能源之一,在当今能源紧缺的时代煤炭显得更为重要。在印度煤炭资源极其丰富,所以绝大多数的发电厂都使用煤炭,这就导致汞和煤粉对环境的污染。如印度中部一家大型燃煤热电站,监测发现离污染源10km的周围大气中,颗粒状汞的浓度6.94~32.29ng/m^3。 展开更多
关键词 热电厂 大气 土壤 植物 污染
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Y染色体细微缺失与反复流产 被引量:1
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作者 Dewan S. Puscheck E.E. +1 位作者 coulam c.b. 马超 《世界核心医学期刊文摘(妇产科学分册)》 2006年第6期20-21,共2页
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
关键词 Y染色体 反复流产 微缺失 男性因素不育 不育夫妇 男性患者 涂片检测 生育男性 DNA检测 临床研究
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10个雌激素相关基因的多态性与子宫内膜异位症:关于多个基因间相互作用的研究
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作者 Huber A. Keck c.c. +2 位作者 Hefler L.A. c.b. Tempfer 朱国栋 《世界核心医学期刊文摘(妇产科学分册)》 2006年第4期59-60,共2页
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
关键词 子宫内膜异位症 雌激素受体Α 测序芯片 多态性 外显率 细胞色素 氧位 激素代谢 寡核苷酸微阵列
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估测卵泡期早期卵泡刺激素(FSH)水平增高的患者卵泡发育终末期初始化的FSH阈值
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作者 De Koning c.H. Schoemaker J. +1 位作者 Lambalk c.b. 石磊 《世界核心医学期刊文摘(妇产科学分册)》 2005年第2期28-29,共2页
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
关键词 卵泡发育 FSH 卵泡刺激素 卵泡数目 黄体中期 小卵泡 大卵泡 高阈 激动剂 试点研究
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北曼哈顿3个种族总同型半胱氨酸水平与认知关系的研究
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作者 Wright c.b. Lee H.-S. +1 位作者 Paik M.c. 陈云春 《世界核心医学期刊文摘(神经病学分册)》 2005年第1期32-33,共2页
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
关键词 认知关系 认知功能 人口统计学 多重线性回归 子后 肾功能 多元分析 子及
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360°周边视网膜切开联合黄斑转位术治疗黄斑地图状萎缩后视网膜色素上皮病变复发的研究
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作者 cahill M.T. Mruthyunjaya P. +2 位作者 Rickman c.b. Toth c.A. 黎黎 《世界核心医学期刊文摘(眼科学分册)》 2005年第11期18-19,共2页
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
关键词 视网膜色素上皮 转位术 周边视网膜 病变复发 老年性黄斑变性 视力丧失 平均视力 眼科中心 术后视力 持续时间
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A Study on an Airgap Control System in a Rotary-Small-Scaled Linear Induction Motor for Railway Vehicles
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作者 c.b. Park b.S. Lee 《Journal of Energy and Power Engineering》 2011年第12期1193-1198,共6页
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
关键词 Airgap control system linear induction motor PROPULSION railway vehicles.
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