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Differing coping mechanisms, stress level and anorectal physiology in patients with functional constipation 被引量:94
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作者 Annie OO Chan Cecilia Cheng +7 位作者 Wai Mo Hui Wayne HC Hu Nina yh Wong KF Lam Wai Man Wong Kam Chuen Lai Shiu Kum Lam Benjamin CY Wong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第34期5362-5366,共5页
AIM: To investigate coping mechanisms, constipation symptoms and anorectal physiology in 80 constipated subjects and 18 controls.METHODS: Constipation was diagnosed by Rome Ⅱ criteria.Coping ability and anxiety/depre... AIM: To investigate coping mechanisms, constipation symptoms and anorectal physiology in 80 constipated subjects and 18 controls.METHODS: Constipation was diagnosed by Rome Ⅱ criteria.Coping ability and anxiety/depression were assessed by validated questionnaires. Transit time and balloon distension test were performed.RESULTS: 34.5% patients were classified as slow transit type of constipation. The total colonic transit time (56 h vs 10 h, P<0.0001) and rectal sensation including urge sensation (79 mL vs 63 mL, P = 0.019) and maximum tolerable volume (110 mL vs95 mL, P = 0.03) differed in patients and controls. Constipated subjects had significantly higher anxiety and depression scores and lower SF-36 scores in all categories. They also demonstrated higher scores of'monitoring' coping strategy (14+6 vs9+3, P = 0.001),which correlated with the rectal distension sensation (P = 0.005), urge sensation (P=0.002), and maximum tolerable volume (P = 0.035). The less use of blunting strategy predicted slow transit constipation in both univariate (P = 0.01) and multivariate analysis (P = 0.03).CONCLUSION: Defective or ineffective use of coping strategies may be an important etiology in functional constipation and subsequently reflected in abnormal anorectal physiology. 展开更多
关键词 CONSTIPATION Anorectal physiology Coping mechanism
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Synthesis and Structure of A Novel Caged Bicyclic Phosphate Flame Retardant 被引量:28
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作者 Li, X Ou, YX +1 位作者 Zhang, yh Lian, DJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第10期887-890,共4页
PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octa... PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper. Its structure was characterized by elemental analysis. FTIR, H-1 NMR. P-31 NMR and X-ray diffraction analysis. 展开更多
关键词 caged bicyclic phosphate flame retardant crystal structure
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bFGF and TGFβ expression in rat kidneys after ischemic/reperfusional gut injury and its relationship with tissue repair 被引量:13
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作者 Yang yh Fu XB +2 位作者 Sun TZ Jiang LX Gu XM 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第1期147-149,共3页
INTRODUCTION Intestinal isehemia/rePerfusion(I/R)oeeureommonly in eritieally 111 Patients.It 15 wellreeognized that gutl/R may eause tissue damageand dysfunetion of intestine,and induee
关键词 Subject headings ISCHEMIA-REPERFUSION INJURY intestinal basic FIBROBLAST GROWTH FACTOR transforming GROWTH FACTOR β gene EXPRESSION
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Increasing dietary fiber intake in terms of kiwifruit improves constipation in Chinese patients 被引量:11
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作者 Annie On On Chan Gigi Leung +1 位作者 Teresa Tong Nina yh Wong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第35期4771-4775,共5页
AIM: To investigate if increased dietary fiber, in terms of kiwifruit, is effective in Chinese constipated patients. METHODS: 33 constipated patients and 20 healthy volunteers were recruited for a 4-wk treatment of ... AIM: To investigate if increased dietary fiber, in terms of kiwifruit, is effective in Chinese constipated patients. METHODS: 33 constipated patients and 20 healthy volunteers were recruited for a 4-wk treatment of kiwi fruit twice daily. Response during wk 1-4 was defined as an increase in complete spontaneous bowl, motion (CSBM)≥ 1/wk. Secondary efficacy included response during wk 1-4, individual symptoms and scores of bowel habits and constipation. Responses were compared with the baseline run-in period. Colonic transit time and anorectal manometry were performed before and after treatment. RESULTS: Responder rate was 54.5% in the constipated group. The mean CSBM increased after treatment (2.2±2.6 vs 4.4± 4.6, P = 0.013). There was also improvement in the scores for bothersomeness of constipation (P = 0.02), and satisfaction of bowel habit (P = 0.001), and decreased in days of laxative used (P = 0.003). There was also improvement in transit time (P = 0.003) and rectal sensation (P 〈 0.05). However, there was no change in the bowel symptoms or anorectal physiology in the healthy subjects. CONCLUSION: Increasing dietary fiber intake is effective in relieving chronic constipation in Chinese population. 展开更多
关键词 CONSTIPATION Dietary fiber KIWIFRUIT CHINESE
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Efficacies of β-L-D4A against Hepatitis B virus in 2.2.15 cells 被引量:9
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作者 Lin-Lin Gao, Xiao-Yan Wang, Ju-Sheng Lin, Ying-Hui Zhang, Yan Li, Institute of Liver Diseases, Tongji Hospital, Tongii Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei Province, China Author contributions:Gao LL and Wang XY contributed equally to this work Gao LL, Wang XY, Lin JS, Zhang yh, Li Y designed the research +1 位作者 Gao LL and Wang XY performed the research Gao LL wrote the paper 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第8期1263-1267,共5页
AIM: To investigate the antiviral effect of beta-L- enantiomer of 2;3'-didehydro-2',3″-dideoxyadenosine (13-L-D4A) on 2.2.15 cells transfected with the hepatitis B virus (HBV) genome.METHODS: Lamivudine (3TC... AIM: To investigate the antiviral effect of beta-L- enantiomer of 2;3'-didehydro-2',3″-dideoxyadenosine (13-L-D4A) on 2.2.15 cells transfected with the hepatitis B virus (HBV) genome.METHODS: Lamivudine (3TC) as a positive control. Then, HBV DNA in treated 2.2.15 cells and the Hepatitis B surface antigen (HBsAg) in the culture supernatants were detected to determine the inhibitory effect of β-L- D4A. At the same time, 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) was used to detect the survival ratio of 2.2.15 cells.RESULTS: β-L-D4A has a dose-dependent inhibitory effect on HBV DNA replication; this effect was apparent when the concentration was above 1 mol/L. When β-L- D4A was at the highest concentration, 100 mol/L, the HBsAg inhibition ratio was above 50%. The Therapeutic index (TI) of β-L-D4A was above 2.1.CONCLUSION: β-L-D4A has a dose-dependent inhibitory effect on the replication of HBV DNA and the secretion of HBsAg at low toxicity, 展开更多
关键词 2 3'-didehydro-2 3'-dideoxyadenosine 2.2.15 cells Hepatitis B virus DNA Hepatitis B surface antigen
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聚谷氨酸批式生物合成的主要影响因素研究 被引量:7
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作者 陆树云 姚俊 +2 位作者 徐虹 李莎 yh 《生物加工过程》 CAS CSCD 2006年第1期65-69,共5页
采用Bacillus subtilis NX-2菌株,在5 L发酵罐批式操作过程中生物合成γ-聚谷氨酸,实验考察了搅拌转速(300~1 000r/min)及底物质量浓度对生物合成γ-聚谷氨酸产率的影响.结果表明:转速为400r/min时,γ-聚谷氨酸产率最高,可高达2... 采用Bacillus subtilis NX-2菌株,在5 L发酵罐批式操作过程中生物合成γ-聚谷氨酸,实验考察了搅拌转速(300~1 000r/min)及底物质量浓度对生物合成γ-聚谷氨酸产率的影响.结果表明:转速为400r/min时,γ-聚谷氨酸产率最高,可高达21.78g/L.在转速400r/min的条件下,考察了葡萄糖和谷氨酸浓度对聚谷氨酸生物合成的影响,根据葡萄糖初始质量浓度为40g/L的实验数据建立了动力学方程.并在葡萄糖初始质量浓度为30,40,50,60g/L的范围内,验证所建动力学方程的稳定性和实用性.结果表明,在以上葡萄糖初始质量浓度范围内,所建模型对B.subtilis NX-2批式生物合成γ-聚谷氨酸产率的预测值与实验值能较好的吻合. 展开更多
关键词 聚谷氨酸 搅拌转速 动力学 分批发酵
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Screening and identification of mimotopes of the major shrimp allergen tropomyosin using one-bead-one- compound peptide libraries 被引量:7
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作者 Nicki yh Leung Christine YY Wai +6 位作者 Marco HK Ho Ruiwu Liu Kit S Lam Jin Jun Wang Shang An Shu Ka Hou Chu Patrick SC Leung 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2017年第3期308-318,共11页
The one-bead-one-compound (OBOC) combinatorial peptide library is a powerful tool to identify ligand and receptor interactions. Here, we applied the OBOC library technology to identify mimotopes specific to the immu... The one-bead-one-compound (OBOC) combinatorial peptide library is a powerful tool to identify ligand and receptor interactions. Here, we applied the OBOC library technology to identify mimotopes specific to the immunoglobulin E (IgE) epitopes of the major shellfish allergen tropomyosin. OBOC peptide libraries with 8-12 amino acid residues were screened with serum samples from patients with shellfish allergy for IgE mimotopes of tropomyosin. Twenty-five mimotopes were identified from the screening and their binding reactivity to tropomyosin-specific IgE was confirmed by peptide ELISA. These mimotopes could be divided into seven clusters based on sequence homology, and epitope mapping by EpiSearch of the clustered mimotopes was performed to characterize and confirm the validity of mimotopes. Five out of six of the predicted epitopes were found to overlap with previously identified epitopes of tropomyosin. To further confirm the mimicry potential of mimotopes, BALB/c mice were immunized with mimotopes conjugated to keyhole limpet hemocyanin and assayed for their capacity to induce tropomyosin-specific antibodies. BALB/c mice that received mimotope immunization were found to have an elevated level of tropomyosin-specific immunoglobulin G, but not mice that received an irrelevant mimotope. This study pioneers the successful application of the OBOC libraries using whole sera to screen and identify multiple shrimp allergen mimotopes and validates their mimicry potential using in vitro, in vivo, and in silico methods. 展开更多
关键词 EPITOPE MIMOTOPE OBOC peptide library TROPOMYOSIN
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在酿酒酵母中共表达XYLA和XKS1基因后利用木糖的初步研究 被引量:5
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作者 李永建 严明 +3 位作者 丁莉 许伟 许琳 yh 《生物加工过程》 CAS CSCD 2006年第4期65-69,共5页
为了使酿酒酵母较好地利用木糖产生乙醇,将来自Thermus thermophilus的木糖异构酶基因XYLA和酿酒酵母自身的木酮糖激酶基因XKS1,构建到酵母表达载体pESC-LEU中,导入酿酒酵母YPH499中,同时成功表达了两种酶基因。该菌以木糖为唯一碳源进... 为了使酿酒酵母较好地利用木糖产生乙醇,将来自Thermus thermophilus的木糖异构酶基因XYLA和酿酒酵母自身的木酮糖激酶基因XKS1,构建到酵母表达载体pESC-LEU中,导入酿酒酵母YPH499中,同时成功表达了两种酶基因。该菌以木糖为唯一碳源进行限氧发酵,木糖的利用率为9.64%,为宿主菌的4.17倍,产生2.22 mmol.L-1的乙醇。同时初步探讨了两种酶基因的表达量对酿酒酵母发酵木糖生成乙醇的影响。木糖异构酶对木糖的利用起关键性的作用,木酮糖激酶的过量表达不利于乙醇生成。 展开更多
关键词 木糖异构酶 木酮糖激酶 木糖 酿酒酵母 乙醇
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Classification of gastric neuroendocrine tumors and its clinicopathologic significance 被引量:5
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作者 Yu, JY Wang, LP +3 位作者 Meng, yh Hu, M Wang, JL Bordi, C 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第2期66-69,共4页
AIMS To study the pathologic classification of gastric neuroendocrine tumors and its clinicopathologic significance. METHODS Paraffin embedded sections of 52 gastric neuroendocrine tumors including 42 carcinoid tu... AIMS To study the pathologic classification of gastric neuroendocrine tumors and its clinicopathologic significance. METHODS Paraffin embedded sections of 52 gastric neuroendocrine tumors including 42 carcinoid tumors, and 10 cases of neuroendocrine carcinoma from 326 patients who underwent resection of stomach carcinomas were studied by immunohistochemical methods including 10 endocrine markers or hormones antibodies and endocrine cells in gastric neuroendocrine tumors and extratumoral mucosa were observed under electromicroscope. RESULTS The 52 gastric neuroendocrine tumors were divided into three types: ① Gastrin dependent type of carcinoid (26 cases) accompanied by chronic atrophic gastritis (CAG) and tumor extension limited to the mucosa or submucosa complicated with hypergastrinemia and G cell hyperplasia. This type was consistently preceded by and associated with generalized proliferation of endocrine cells in the extratomoral fundic mucosa. ② Non gastrin dependent type of carcinoids (16 cases) associated with neither CAG nor hypergastrinemia. This type was more aggressive; and ③ Neuroendocrie carcinomas (10 cases), which are highly aggressive tumors. CONCLUSIONS A correct identification of different types of gastric endocrine tumors has major implications for the treatment and prognosis of the patients. 展开更多
关键词 stomach neoplasms/pathology NEUROENDOCRINE tumors/pathology CARCINOID tumor/pathology gastritis ATROPHIC G cell immunohistochemistry microsocopy electron
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Dot immunogold filtration assay for rapid detection of anti-HAV IgM in Chinese 被引量:5
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作者 Han FC Hou Y +2 位作者 Yan XJ Xiao LY Guo yh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期400-401,共2页
INTRODUCTION The hepatitis A virus specific immunoglobulin M(IgM)antibody is a specific serological marker forearly diagnosis of hepatitis A..At present,themethods used at home or abroad for detecting anti-HAV IgM are... INTRODUCTION The hepatitis A virus specific immunoglobulin M(IgM)antibody is a specific serological marker forearly diagnosis of hepatitis A..At present,themethods used at home or abroad for detecting anti-HAV IgM are RIA,ELISA and SPHAI.The dotimmunogold combination assay that has beendeveloped since 1989 is a new technique with theproperty of simple and rapid immunologicaldetection,by using the red colloidal gold particles tolabel the antibodies as indicator,and the 展开更多
关键词 DOT IMMUNOGOLD FILTRATION assay HEPATITIS A virus IMMUNOGLOBULIN M/analysis
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Child-Pugh-Turcott versus Meld score for predicting survival in a retrospective cohort of black African cirrhotic patients 被引量:5
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作者 KA Attia KC Ackoundou-N'guessan +4 位作者 AT N’dri-yoman AK Mahassadi E Messou YF Bathaix yh Kissi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期286-291,共6页
AIM: To compare the performance of the Child-Pugh-Turcott (CPT) score to that of the model for end-stage liver disease (MELD) score in predicting survival of a retrospective cohort of 172 Black African patients with c... AIM: To compare the performance of the Child-Pugh-Turcott (CPT) score to that of the model for end-stage liver disease (MELD) score in predicting survival of a retrospective cohort of 172 Black African patients with cirrhosis on a short and mid-term basis.METHODS: Univariate and multivariate (Cox model) analyses were used to identify factors related to mortality. Relationship between the two scores was appreciated by calculating the correlation coefficient. The Kaplan Meier method and the log rank test were used to elaborate and compare survival respectively. The Areas Under the Curves were used to compare the performance between scores at 3, 6 and 12 mo.RESULTS: The study population comprised 172 patients, of which 68.9% were male. The mean age of the patient was 47.5 ± 13 years. Hepatitis B virus infection was the cause of cirrhosis in 70% of the cases. The overall mortality was 31.4% over 11 years of follow up. Independent factors significantly associated with mortality were: CPT score (HR = 3.3, 95% CI [1.7-6.2]) (P < 0.001) (stage C vs stage A-B); Serum creatine (HR = 2.5, 95% CI [1.4-4.3]) (P = 0.001) (Serum creatine > 1.5 mg/dL versus serum creatine < 1.5 mg/dL); MELD score (HR = 2.9, 95% CI [1.63-5.21]) (P < 0.001) (MELD > 21 vs MELD < 21). The area under the curves (AUC) that predict survival was 0.72 and 0.75 at 3 mo (P = 0.68), 0.64 and 0.62 at 6 mo (P = 0.67), 0.69 and 0.64 at 12 mo (P = 0.38) respectively for the CPT score and the MELD score.CONCLUSION: The CPT score displays the sameprognostic significance as does the MELD score in black African patients with cirrhosis. Moreover, its handling appears less cumbersome in clinical practice as compared to the latter. 展开更多
关键词 Model for end-stage liver disease score Child score CIRRHOSIS Black African SURVIVAL
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Association of polymorphisms in the vascular endothelial growth factor gene and its serum levels with diabetic retinopathy in Chinese patients with type 2 diabetes: A cross-sectional study 被引量:4
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作者 Fan XH Wu QH +5 位作者 Li Y Hao yh Ning N Kang Z Cui Y Liu RH 《Chinese Medical Journal》 SCIE CAS CSCD 2014年第4期651-657,共7页
Background Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis,and plays a key role in the pathogenesis of diabetic retinopathy (DR).This study was designed to identify the possible role ... Background Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis,and plays a key role in the pathogenesis of diabetic retinopathy (DR).This study was designed to identify the possible role of VEGF gene polymorphisms in the development of DR in type 2 diabetic patients in Chinese and clarify the relationship between VEGF serum levels and the risk of DR.Methods This cross-sectional study included 1 040 Chinese subjects with type 2 diabetes mellitus.There were 372 patients diagnosed with DR in the case group and 668 patients without DR in the control group.DNA from each patient was analyzed for VEGF polymorphisms of-2578A/C (rs699947),-1154G/A (rs1570360),-460C/T (rs833061),+405C/G (rs2010963),and +936C/T (rs3025039) using MassARRAY compact analyzer.The VEGF serum levels were quantified by enzyme-linked immunosorbent assay (ELISA).Results No evidence of association was observed between-2578 A/C (rs699947),+405C/G (rs2010963),+936C/T (rs3025039),and DR risk under stringent Bonferroni&#39;s correction.However,VEGF serum levels were significantly higher in DR patients than those of control group.The genetic variation of VEGF polymorphisms influenced VEGF serum levels; subjects carrying the VEGF-2578 C/C (rs699947) genotype had greater VEGF serum levels than those carrying the C/A genotype and VEGF serum levels were significantly higher in CC genotype of the +405C/G (rs2010963) compared with those of the other genotypes.Conclusions The data did not suggest significant association between the VEGF polymorphisms and DR risk under stringent Bonferroni&#39;s correction.However,our study indicated that DR patients have higher VEGF levels than diabetic patients without retinopathy,and-2578A/C (rs699947) and +405C/G (rs2010963) may be important factors in determining serum VEGF levels. 展开更多
关键词 vascular endothelial growth factor POLYMORPHISM GENETICS diabetic retinopathy
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Relationship between polymetallic nodules and submarine hydrothermalism in the Central Pacific Ocean 被引量:4
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作者 Li, yh Song, HB +1 位作者 Li, JC Yao, XM 《Chinese Science Bulletin》 SCIE EI CAS 1997年第23期1980-1983,共4页
THE huge reserves of submarine polymetallic nodules make them an important kind of potentialmineral resources. It has already been discovered that polymetallic nodules are related withsubmarine vollcanogene hydrotherm... THE huge reserves of submarine polymetallic nodules make them an important kind of potentialmineral resources. It has already been discovered that polymetallic nodules are related withsubmarine vollcanogene hydrothermalism. For example, pyroclasts usually occur as coresubstances of the nodules, and large amounts of mineralizing materials such as manganese aredischarged to form ferromanganese oxides along with the submarine vocanogene hydrothermal- 展开更多
关键词 POLYMETALLIC NODULES SUBMARINE hydrothermalism HELIUM isotope.
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Nitrite-derived nitric oxide by xanthine oxidoreductase protects the liver against ischemia- reperfusion injury 被引量:4
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作者 Department of General Surgery ( Lu P, Wang CY and Chen DD), and Department of Radiology (Liu F), Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China Cold Spring Harbor Laboratory, New York 11724, USA ( Yao Z) General Surgery Laboratory, Union Hospital, Tongji Medical College , Huazhong University of Science and Technology, Wuhan 430022 , China (Tian Y, Zhang JH and Wu yh) 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第3期350-355,共6页
It was demonstrated that xanthine oxidoreductase (XOR), during ischemia, catalyzes the formation of nitric oxide (NO) from nitrite (NO_2^-) and this NO_2^--derived NO protects the isolated perfused rat heart against t... It was demonstrated that xanthine oxidoreductase (XOR), during ischemia, catalyzes the formation of nitric oxide (NO) from nitrite (NO_2^-) and this NO_2^--derived NO protects the isolated perfused rat heart against the damaging effects of ischemia-reperfusion (I/R) when conventional nitric oxide synthase (NOS) -dependent NO production is impaired. Liver is one of the organs with the highest XOR concentration. This study was designed to determine whether NO_2^--derived NO by XOR protects liver against I/R injury in vivo. For its minute amounts and active reactivity, NO can not be detected directly in real time in vivo by this time. We have to prove the above hypothesis indirectly. METHODS:Wistar rats were pretreated with saline, NOS inhibitor L-NAME (10 mg/kg intravenously), XOR inhibitor allopurinol (1.5 mg/kg orally), L-NAME +allopurinol and NO scavenger carboxy-PTIO (0.6 mg/kg intravenously) respectively (12 animals per group). And then, they were subjected to total liver ischemia for 40 minutes followed by reperfusion. Blood samples and liver tissues were obtained for analysis after 3 hours of reperfusion. Survival was also investigated. RESULTS:Allopurinol-treated animals exhibited further increased serum alanine aminotransferase (ALT) levels and liver myeloperoxidase (MPO) activities, but further decreased liver adenosine triphosphate (ATP) stores after I/R compared to saline-treated counterparts (830.5±108.3 U/L, 56.5±11.0 U/mg protein and 1.93±0.47 μmol/g vs. 505.8± 184.2 U/L, 41.5±10.2 U/mg protein and 3.05±0.55 μmol/g respectively, P<0.01, P<0.05 and P<0.01 respectively). The hepatocyte injury was further exacerbated and the overall survival rate was significantly decreased after I/R in animals given by allopurinol compared to those pretreated by saline (P<0.05). L-NAME and allopurinol co-treated animals exhibited more severe liver injury (P<0.05 and P<0.01) and a further decreased overall survival rate (P<0.05) compared to L-NAME or allopurinol alone-treated counterparts, but they were not diff 展开更多
关键词 NITRITES nitric oxide ischemia-reperfusion injury
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引发剂对酶促开环聚合ε-己内酯的影响 被引量:4
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作者 马玖彤 李全顺 +3 位作者 王元鸿 韩四平 冯雁 yh 《生物加工过程》 CAS CSCD 2006年第4期26-31,共6页
通过脂肪酶Novozym 435催化的ε-己内酯开环聚合反应,在无溶剂体系中研究了聚己内酯的合成及末端官能化。以醇类为引发剂,研究了引发剂对聚合过程单体转化率、产物结构和相对分子质量的影响。结果表明,在引发剂存在的条件下,反应速率提... 通过脂肪酶Novozym 435催化的ε-己内酯开环聚合反应,在无溶剂体系中研究了聚己内酯的合成及末端官能化。以醇类为引发剂,研究了引发剂对聚合过程单体转化率、产物结构和相对分子质量的影响。结果表明,在引发剂存在的条件下,反应速率提高,产物相对分子质量降低。无引发剂时单体转化率为79.32%,乙醇和乙二醇为引发剂时分别为97.43%和89.90%。产物相对分子质量在无引发剂时为5 393,乙醇和乙二醇为引发剂时分别下降到2 127和1 851。另外,产物的红外光谱和1H NMR谱图显示,引发剂的加入实现了聚合物的末端官能化。 展开更多
关键词 脂肪酶 Ε-己内酯 开环聚合 引发剂 无溶剂条件
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VIP immunoreactive nerves and somatostatin and serotonin containing cellsin Crohn′s disease 被引量:4
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作者 Lu SJ Liu YQ +3 位作者 Lin JS Wu HJ Sun yh Tan YB 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第6期541-543,共3页
关键词 vasoactive intestinal peptide SOMATOSTATIN SEROTONIN Crohn′s disease immunohistochemistry HISTOMORPHOMETRY
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Three-year outcomes of patients with non-valvular atrial fibrillation: the COOL-AF registry
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作者 Rungroj Krittayaphong Satchana Pumprueg +2 位作者 Pontawee Kaewkumdee Ahthit Yindeengam Gregory yh Lip 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2023年第3期163-173,共11页
BACKGROUND Clinical outcomes of patients with non-valvular atrial fibrillation(AF)in Asian populations may be different from non-Asians.In this study,we aimed to determine the incidence of ischemic stroke/systemic emb... BACKGROUND Clinical outcomes of patients with non-valvular atrial fibrillation(AF)in Asian populations may be different from non-Asians.In this study,we aimed to determine the incidence of ischemic stroke/systemic embolism(SSE),major bleeding,and death,and the predictors for clinical outcomes in a contemporary Asian cohort of newly diagnosed AF patients.METHODS This is a prospective multicenter nationwide registry of patients with AF from 27 hospitals in Thailand.Baseline data and follow-up data were collected every 6 months until 3 years.Data collections included demographic,medical history,laboratory,and medication details.Clinical outcomes were SSE,major bleeding,and all-cause mortality.Incidence rates for each clinical outcome were calculated and presented as rate per 100 person-years.Univariate and multivariate analysis was performed to determine the independent predictors for clinical outcomes.RESULTS There was a total of 3405 patients:mean age was 67.8±11.3 years,1981(58.2%)were male.During 30.8±9.7 months follow-up,there was a total of 132 SSE(3.9%),191 major bleeding(5.6%),and 357 all-cause deaths(10.5%).The incidence rates of SSE,major bleeding,and death were 1.56(1.30-1.84),2.26(1.96-2.61),and 4.17(3.33-4.25),per 100 person-years respectively.Independent predictors for clinical outcomes were age,type of AF,and the presence of comorbid conditions.CONCLUSION The incidence rate of SSE,major bleeding,and death remains high reflecting the unmet needs in AF management。 展开更多
关键词 PATIENTS FIBRILLATION MORTALITY
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Application of Nanopowder to High Temperature Single Crystal Fiber Sensor 被引量:3
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作者 Wang, YQ Wu, XJ +2 位作者 Ye, LH Tong, LM Shen, yh 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期364-366,共3页
ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head co... ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head coated with above mixed nanopowder shows better optical stability, shorter response time and higher thermal shock resistance, in comparison with the head coated with coarse-grained particles with the same chemical compositions. 展开更多
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Investigation on the Microstructure Homogenization in a TiAl Based Alloy Prepared by Elemental Powder Metallurgy 被引量:2
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作者 Liu, Y Huang, BY +1 位作者 He, yh Wang, JN 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第6期527-530,共4页
A Ti-48Al (at. pet) alloy prepared by elemental powder metallurgy (EPM) has been heat treated under various conditions. Through optical and scanning electronic microscopy, EDAX, XRD analysis, and DTA, it was shown tha... A Ti-48Al (at. pet) alloy prepared by elemental powder metallurgy (EPM) has been heat treated under various conditions. Through optical and scanning electronic microscopy, EDAX, XRD analysis, and DTA, it was shown that the hot pressed microstructure consisted of alpha(2)-Ti3Al and TiAl phases. The alpha(2)-Ti3Al phase was island-like, and had a high stability and heredity in subsequent heat treatments. The supersaturation of Al in the island-like alpha-Ti3Al phase strongly influenced the transformation of alpha(or alpha(2)) to alpha(2)/gamma lamellar colonies. After a heat treatment at 1380 degrees C for 0.5 h and 1000 degrees C for 8 h, a fully lamellar microstructure with a colony size of 50 mu m was obtained. This result indicates that a homogeneous composition and an equilibrium microstructure in EPM TiAl-base alloys can only be obtained after heat treatment at temperatures above alpha transus temperature (T-alpha). 展开更多
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Dissolution-facilitating Dislocation Emission, Motion andInitiation of SCC in 310 Stainless Steel 被引量:2
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作者 Huang, yh Chen, QZ Chu, WY 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第6期483-486,共4页
Using a special constant deflection device, the in situ TEM observations of dislocation emission, motion and the initiation of nanocrack in 310 stainless steel in water were carried out. The results show that SCC in t... Using a special constant deflection device, the in situ TEM observations of dislocation emission, motion and the initiation of nanocrack in 310 stainless steel in water were carried out. The results show that SCC in thin foil specimen of 310 stainless steel can occur in water. A nanocrack initiated in the DFZ or at the blunt crack tip in corrosion solution after dislocation emission, multiplication and motion, which were induced by the localized anodic dissolution, reached a critical condition. The nanocrack propagated by a cleavage mode because of the influence of the corrosion solution. 展开更多
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