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41.
小鼠卵细胞质内显微注入单精子受精的实验研究   总被引:8,自引:0,他引:8  
杨益寿  熊素芳  龙文  李鸣  夏明珠  汪昌介 《解剖学报》1998,29(4):441-445,I011
为了探讨提高小鼠卵细胞质内单精子注入受精率的方法,选取鼠龄12-14周的健康昆明白小鼠作为精子和卵子的供体,受用ICSI技术,以受精后二细胞卵裂的形成率为指标,了解不同采卵时间,不同微注射针参数及不同培养液对细胞质单精子注入的影响。结果表明,hCG注射后18-19h采卵,用针尖内径为4-5μm,斜面角度为35-40度的微注射针进行ICSI操作受精后卵子置CZB中培养可获得较多的2细胞胚,卵裂率明显  相似文献   
42.
We detected the presence and distribution of HBcAg in the liver by immunohistochemistry (ABC method) and the presence of HBV-DNA in serum (spot hybridization) and anti-HBe in serum (ELISA) from 59 cases of hepatitis B hospitalized in our hospital, including 47 cases of CAH, 5 cases of CPH, and 7 cases of subacute fulminant hepatitis. 1. HBcAg in the liver was detected in 25 out of 47 cases (53%) of CAH, in 2 out of 5 cases of CPH and in 4 out of 7 cases of subacute fulminant hepatitis. The total percentage was 53% (31/59). 2. There was no positive correlation between HBV replication activity and liver disease activity (P greater than 0.05). Our results did not support the hypothesis that suggests a direct cytopathic effect of HBV. Oppositely, the fact was that the presence, the amount and the patterns of HBcAg in the liver, and the presence of HBV-DNA in serum were predominant in mild CAH compared with those in severe CAH, predominant in CAH without cirrhosis compared with those in CAH with cirrhosis. There was a tendency of inverse correlation between HBV replication activity and liver disease activity. The results above were in line with the concept that HBcAg expressed on the surface of infected hepatocytes may be relevant target for T lymphocyte cytotoxicity. The results have suggested that an immune response to HBV is present, leading to the destruction of most infected cells. 3. There was a positive correlation between HBV-DNA in serum and HBcAg in the liver (P less than 0.005), indicating that HBV-DNA in serum can represent HBV replication.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
43.
[目的]比较2,4-二氯苯胺重氮法(DCA)和钒酸盐氧化法检测血清结合胆红素的结果。[方法]根据NCCLS(EP6-P)评价方案,评估两种方法的相关性和偏倚。[结果]两种方法的检测结果相关性良好(r=0.9985),Ⅰ、Ⅱ、Ⅲ组检测结果无差异,Ⅳ组结果有差异。[结论]应建立与方法学相对应的血清结合胆红素参考值范围。  相似文献   
44.
We have examined polyol pathway kinetics in the lenses of rats made diabetic with streptozotocin. At up to 11 days after diabetes induction, the lenses were isolated and subjected to 'pulse-chase' studies: the lenses were incubated with [13C]glucose and lens metabolism followed by [13C]nuclear magnetic resonance (NMR) spectroscopy. Proton NMR spectroscopy was also performed to measure the hexose monophosphate shunt (HMPS) activity. The results showed that (1) the activity of aldose reductase increased initially and decreased after 11 days of diabetes; (2) the fructose pool increased initially but started to decline after 3 days; (3) the HMPS activity increased nearly 40% immediately after diabetes induction; and (4) the turnover rates of glucose, alpha-glycerophosphate (GP), lactate, sorbitol, and fructose were 80.8 +/- 2.6, 10.1 +/- 1.4, 47.7 +/- 3.7, 7.9 +/- 0.9 and 5.2 +/- 2.2 nmol hr-1 lens-1 (34 mg wet weight lens-1), respectively. Up to 35% of lactate appeared to derive from the polyol pathway. Further, GP was rapidly metabolized, although its fate is currently unknown. These results reveal a far more complex pattern of glucose metabolism in the diabetic lens than that in lenses incubated in high glucose.  相似文献   
45.
46.
跳伞对空降兵脂质过氧化系统影响的初步研究   总被引:6,自引:2,他引:4  
为探讨跳伞对空降兵脂质过氧化水平的影响和可能的生物学意义,测定了跳伞与否空降兵血浆中超氧化物歧化酶、谷胱甘肽过氧化物酶、谷胱甘肽硫转移酶的活性和丙二醛浓度,并与正常人群的值作了比较分析。结果显示,与正常人群相比,未跳伞空降兵血浆中超氧化物歧化酶、谷胱甘肽过氧化物酶、谷胱甘肽硫转移酶的活性和丙二醛浓度增高,但无显著性差异(P〉0.05);与未跳僮空军兵相比,跳伞后空降兵血浆三种酶活性略为增高,但无显  相似文献   
47.
创面异体移植培养表皮细胞后存活的判定   总被引:1,自引:0,他引:1  
应用4种方法判定烧伤创面异体移植的培养表皮细胞存活情况:1.聚合酶链反应(PCR)查Y染色体特异性DNA片段;2.PCR扩增PMCT118长度多态性基因位点;3.PCR/SSOHLA-DQa分型;4.DNA指纹。共检测16例病人的27个活检标本,均证实有供者的DNA,最长时间为移植后92天。初步实验结果表明:培养表皮异体移植后可存活较长时间。  相似文献   
48.
49.
Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.  相似文献   
50.
用放射免疫分析法和比浊法测定PAI0134对大鼠血浆血栓素B2浓度,血小板TXB2生成血小板聚集的影响。静脉注射API013470mg或100mg.kg显著降低血浆TXB2浓度,其降低2率分别为38.8%和51.6%,API0134明显抑制ADP诱导的大鼠血小板聚集和TXB2生成,抑制率分别为27.8%,39.5%,和41.4%,53.6%,两抑制率间呈显著正相关。  相似文献   
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