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71.
乙醇对人绒毛孕酮分泌的影响   总被引:1,自引:0,他引:1  
本工作利用灌流技术观察了四种不同浓度的乙醇(0.5%、1%、2.5%、5%)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。  相似文献   
72.
合成了一系列分子量较低的聚乙二醇.聚己内酯-聚乙二醇(Poly(ethylene glycol)-Polycaprolactone-Poly(ethylene glycol),PEG-PCL—PEG)三嵌段共聚物。分别采用FTIR和1H—NMR对其结构进行了表征。所合成的PEG-PCL-PEG共聚物具有良好的水溶性,当水溶液浓度高于临界凝胶浓度(Critical gel concentration,CGC)时,随着温度的变化聚合物水溶液会呈现特有的凝胶-溶胶转变。研究了共聚物亲水疏水链段的比例和长度,以及热历史等对凝胶-溶胶转变行为的影响。通过调节上述条件,可以在一定程度上拓宽凝胶-溶胶转变温度范围,有助于PEG—PCL-PEG水凝胶在可注射药物控制释放系统等方面的应用。  相似文献   
73.
74.
MCP-1-dependent signaling in CCR2(-/-) aortic smooth muscle cells   总被引:1,自引:0,他引:1  
Monocyte chemoattractant protein-1 (MCP-1, CCL2) is a mediator of inflammation that has been implicated in the pathogenesis of a wide variety of human diseases. CCR2, a heterotrimeric G-coupled receptor, is the only known receptor that functions at physiologic concentrations of MCP-1. Despite the importance of CCR2 in mediating MCP-1 responses, several recent studies have suggested that there may be another functional MCP-1 receptor. Using arterial smooth muscle cells (SMC) from CCR2(-/-) mice, we demonstrate that MCP-1 induces tissue-factor activity at physiologic concentrations. The induction of tissue factor by MCP-1 is blocked by pertussis toxin and 1,2-bis(O-aminophenyl-ethane-ethan)-N,N,N',N'-tetraacetic acid-acetoxymethyl ester, suggesting that signal transduction through the alternative receptor is G(alphai)-coupled and dependent on mobilization of intracellular Ca(2+). MCP-1 induces a time- and concentration-dependent phosphorylation of the mitogen-activated protein kinases p42/44. The induction of tissue factor activity by MCP-1 is blocked by PD98059, an inhibitor of p42/44 activation, but not by SB203580, a selective p38 inhibitor. These data establish that SMC possess an alternative MCP-1 receptor that signals at concentrations of MCP-1 that are similar to those that activate CCR2. This alternative receptor may be important in mediating some of the effects of MCP-1 in atherosclerotic arteries and in other inflammatory processes.  相似文献   
75.
动脉导管溶栓治疗急性肢体动脉栓塞14例分析   总被引:3,自引:0,他引:3  
目的 探讨动脉导管溶栓治疗急性肢体动脉栓塞的方法和疗效。方法回顾性分析14例肢体动脉栓塞的诊断方法和介入手术治疗方案。结果治愈11例,治愈率78.6%(11/14);2例好转。无患肢缺血坏死或截肢,无术后因肾功能衰竭死亡。结论动脉导管溶栓是治疗急性肢体动脉栓塞有效的方法,值得进一步开展和探索。  相似文献   
76.
乙型肝炎病毒前S1抗原检测及其临床意义   总被引:10,自引:0,他引:10  
为探讨检测乙型肝炎病毒前S1抗原(Pre-S1Ag)的临床意义,本文对338例各型乙型肝炎患者进行Pre-S1Ag检测,同时检测HBV标志物和HBV-DNA,对其阳性率及相互关系进行分析比较.结果表明:338例患者,Pre-S1Ag阳性检测率为63.02%,HBeAg阳性检测率为48.52%,HBV-DNA阳性检测率为68.05%.Pre-S1Ag阳性与HBV-DNA阳性的符合率为78.56%;Pre-S1Ag与HBeAg阳性的符合率为81.17%;Pre-S1Ag与HBeAg、HBV-DNA具有显著相关性(P<0.01),提示Pre-S1Ag能够较好地反映病毒复制状况,有可能作为体内病毒复制存在的实验室指标.  相似文献   
77.
Artificial liver support system (ALSS) has been used to treat hepatic failure and has significantly decreased the mortality. TECA hybrid artificial liver support system (TECA-HALSS), which combines the hollow fiber bioreactor with a plasma exchange circuit, was used to assess the efficacy, safety and feasibility in treating severe hepatitis patients. The hybrid artificial liver support system (HALSS) consists of a bioreactor containing more than 5 x10(9) porcine hepatocytes and plasma exchange device. Fifteen patients with severe hepatitis were treated with this hybrid system. All patients experienced a reduction in symptoms such as fatigue, abdominal distention or ascites. After each treatment serum total bilirubin decreased markedly while prothrombin activity increased. There were ten patients whose progress of hepatocyte necrosis was stopped after HALSS treatment, and finally they recovered completely. One patient received liver transplantation after HALSS therapy and survived. No serious adverse events were noted in the fifteen patients.  相似文献   
78.
Multi-virulence-locus sequence typing (MVLST) was used to analyze isolates from two major listeriosis outbreaks in the United States in 1998 and 2002 that were due to consumption of contaminated hot dogs and turkey deli meat, respectively. MVLST demonstrated high epidemiological relevance and indicated that the two outbreaks were the result of one epidemic.  相似文献   
79.
氧化苦参碱对LAK细胞活性的影响   总被引:18,自引:0,他引:18  
LAK细胞具有很强的广谱杀瘤作用,而氧化苦参碱具有较强的免疫抑制作用。本文研究了氧化苦参碱对LAK细胞活力的影响,结果表明:氧化苦参碱可抑制IL-2对小鼠脾细胞的促增殖作用,并且对IL-2活化LAK细胞杀伤P815的能力也有抑制作用。当IL-2(500u/ml)与200μg/ml的氧化苦参碱共同孵育4d后,可使LAK细胞杀瘤能力(在效靶比为100:1时)的82.5%被抑制。同时氧化苦参碱本身对P8  相似文献   
80.
Summary Two partial cDNA clones of genes 5 (encoding the major inner capsid protein VP 6) and 6 (encoding a nonstructural protein) of the porcine group (Gp) C rotavirus (Cowden strain) were radiolabeled with32P and used individually as probes in Northern and dot blot hybridization assays. The specificity of each probe was tested against genomic dsRNA from: (1) porcine Gp A, B, and C rotaviruses; (2) Gp C rotaviruses from different species; and (3) porcine Gp C rotavirus field strains with varying electropherotype patterns. Neither probe hybridized with ds RNA from the porcine Gp A and B strains under the stringency conditions employed in the study. However, the gene 5 probe hybridized with the corresponding gene from the homologous porcine and the heterologous human and bovine Gp C rotaviruses tested. The gene 6 probe hybridized with the corresponding gene from the homologous Cowden strain, but hybridized weakly with gene 6 from the human and bovine Gp C rotaviruses. Both probes recognized all six different porcine Gp C field strains, although with varying intensities. Our results demonstrate that the gene 5 and 6 probes used in this study are specific for Gp C rotaviruses. However, evidence for greater genetic variation in the gene 6 among porcine, bovine and human Gp C strains suggested that the gene 5 probe may prove more broadly reactive among Gp C strains from different species. cDNA probes used in our study should prove useful for the detection of Gp C rotaviruses in feces and facilitate epidemiologic studies.  相似文献   
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