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The aim of the study was to conduct a structured review of theliterature published on the use of normal sperm morphology,as an indicator of male fertility potential in the in-vitrofertilization (IVF) situation, and to establish the universalpredictive value of this semen parameter. Published literaturein which normal sperm morphology was used to predict fertilizationand pregnancy, during the period 1978-1996, was reviewed. Atotal of 216 articles were identified by the sourcing methodology,but only 49 provided data that could be tabulated and analysed.Of these, only 18 provided sufficient data for statistical analysis.Fifteen studies used the strict criteria to evaluate sperm morphology,two used World Health Organization (WHO) guidelines and oneused both the strict criteria and the WHO guidelines. All thestudies (n=10) using the 5 and 14% normal sperm morphology thresholds(strict criteria) produced positive predictive values for IVFsuccess. In the prediction of pregnancy, 82% (9/11) and 75%(6/8) of the studies produced positive predictive values whenusing the 5% and 14% thresholds respectively. Aggregating thedata produced around the 5% normal sperm morphology threshold(strict criteria), the overall fertilization rates were 59.3%(1979/3337; per oocyte) for the 4% group and 77.6% (10345/13327;per oocyte) for the >4% group, and the overall pregnancyrates were 15.2% (60/395; per cycle) and 26.0% (355/1368; percycle) respectively. The no-transfer rates across the 5% thresholdwere 24.0% (86/359; per cycle) in the 4% group compared to 7.4%(80/1088; per cycle) in the >4% group. The inclusion of anaccurately evaluated normal sperm morphology count as an integralpart of the standard semen analysis makes this analysis stillthe most cost-effective means of evaluating the male factor. 相似文献
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44.
阮强 《中华微生物学和免疫学杂志》1994,(5)
研究资料表明,人巨细胞病毒(HCMv)单一蛋白的单一抗原决定簇只能被部分患者阳性血清识别。组建在血清学诊断中能够替代全病毒抗原的基因工程抗原,需要含有病毒多种主要抗原蛋白的抗原决定簇。为搞清在表达载体中重复插入某一抗原决定簇基因是否能表达出更高抗原效价的融会蛋白,我们用点突变的方法,在表达载体中分别插入了人HCMv的ppUL32蛋白羧基端一个抗原决定簇基因的1个、2个和3个拷贝。在免疫转印检测中,这些克隆表达的融合蛋白与特异性阳性血清的反应性差别不明显。这表明,插入表达载体中目的基因的多寡对表达蛋白的抗原效价没有显著影响。 相似文献
45.
我们以前曾报道,表达单纯疱疹病毒Ⅱ型糖蛋白D(HSV-2gD)的重组痘苗病毒(实验疫苗株)能保护被免疫小鼠抵抗致死量HSV-2病毒的攻击。在此工作基础上,严格按人用疫苗研究要求的实验条件,成功地建立了表达HSV-2gD的重组痘苗病毒活疫苗株。首先将经聚合酶链反应(PCR)修饰的HSV-2gD基因插入痘苗表达质粒pJSB1175,置于痘苗病毒P75K早/晚期启动子控制下。将此重组质粒用Lipofectin方法转染已受野型TK+痘苗病毒天坛761株感染的人胚肺二倍体细胞。经同位素探针(32P-HSV-2gD)原位杂交法和3轮蚀斑纯化,筛选出基因组内整合有HSV-2gD基因的重组痘苗病毒。斑点和Southern杂交证实,HSV-2gD基因已插入痘苗病毒基因组内预期的TK区段,间接免疫荧光检测显示,重组病毒感染细胞后能有效地表达HSV-2gD蛋白。 相似文献
46.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
47.
Mei Shuang Jing Liu Mei Xiang Jia Jian Zhong Yang Su Ping Wu Xiao Hong Gong Yan Su Ling Yan Ruan Xiao Ling Yang Dai Zhang 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):48-50
The glutamate pathways are involved in diverse processes such as learning and memory, epilepsy, and they play important roles in neural plasticity, neural development, and neurodegeneration. It has been proposed that autism could be a hypoglutamatergic disorder. Recently, Jamain et al. reported that the glutamate receptor 6 (GluR6 or GRIK2) is in linkage disequilibrium with autism. In the present study, the transmission disequilibrium test (TDT) and the haplotype transmission were performed to analyze the four SNPs (SNP1: rs995640; SNP2: rs2227281; SNP3: rs2227283; SNP4: rs2235076) of GluR6 in 174 Chinese Han parent-offspring trios. The TDT demonstrated that the two SNPs (SNP2 and SNP3) showed preferential transmission (TDT P = 0.032). The global chi(2) test for haplotype transmission also revealed an association between GluR6 and autism (chi(2) = 10.78, df = 3, P = 0.013). Our results suggested that GluR6 is in linkage disequilibrium with autism. 相似文献
48.
大鼠肝内移植肿瘤与肥大细胞关系的形态学研究 总被引:3,自引:0,他引:3
目的:研究大鼠肝内移植肿瘤与其周边肥大细胞的关系。方法:建立40只雄性Wistar大鼠肝内移植肿瘤模型,运用HE染色,肥大细胞(mast cell,MC)Alcian blue特殊染色,苦味酸-天狼猩红染色和电镜等技术,观察移植肿瘤肝组织的形态学改变,肿瘤周边浸润MC的数量以及MC与肿瘤组织的关系,8只正常大鼠为对照组。结果:肿瘤组织周边部分肝细胞形态学异常;肝组织内胶原纤维增生,主要为Ⅰ型和Ⅲ型胶原,并包绕肿瘤组织,肿瘤周边MC浸润,并沿胶原纤维分布,不同大鼠其肿瘤周边MC数量不一,有的差异明显。超微结构观察显示MC通过多个接触点与肿瘤细胞紧密相连,并释放胞质颗粒内容物,导致肿瘤细胞崩解。结论:MC与肿瘤组织有着非常密切的关系,MC可能通过多种途径直接和间接地发挥抗肿瘤作用。 相似文献
49.
An animal model of SARS produced by infection of Macaca mulatta with SARS coronavirus 总被引:16,自引:0,他引:16
Qin C Wang J Wei Q She M Marasco WA Jiang H Tu X Zhu H Ren L Gao H Guo L Huang L Yang R Cong Z Guo L Wang Y Liu Y Sun Y Duan S Qu J Chen L Tong W Ruan L Liu P Zhang H Zhang J Zhang H Liu D Liu Q Hong T He W 《The Journal of pathology》2005,206(3):251-259
A new SARS animal model was established by inoculating SARS coronavirus (SARS-CoV) into rhesus macaques (Macaca mulatta) through the nasal cavity. Pathological pulmonary changes were successively detected on days 5-60 after virus inoculation. All eight animals showed a transient fever 2-3 days after inoculation. Immunological, molecular biological, and pathological studies support the establishment of this SARS animal model. Firstly, SARS-CoV-specific IgGs were detected in the sera of macaques from 11 to 60 days after inoculation. Secondly, SARS-CoV RNA could be detected in pharyngeal swab samples using nested RT-PCR in all infected animals from 5 days after virus inoculation. Finally, histopathological changes of interstitial pneumonia were found in the lungs during the 60 days after viral inoculation: these changes were less marked at later time points, indicating that an active healing process together with resolution of an acute inflammatory response was taking place in these animals. This animal model should provide insight into the mechanisms of SARS-CoV-related pulmonary disease and greatly facilitate the development of vaccines and therapeutics against SARS. 相似文献
50.
In order to investigate the role of monocyte/macrophages and their relationship to the expression of macrophage colony-stimulating factor (MCSF) in pulmonary atherosclerosis, lungs were excised from rabbits that had been fed for 60 and 90 days on a diet containing 0.5% cholesterol. In the lungs, fatty streaks and elevated foam cell lesions predominated in the large or medium-sized elastic pulmonary arteries, while massive accumulation of foam cells in the intima of muscular arteries produced marked luminal narrowing and nearly complete occlusion. In these lesions, most of the foam cells were reactive with RbM2, a monoclonal antibody (mAb) against rabbit macrophages, while smooth muscle cell-derived foam cells were detected by mAb against smooth muscle actin in the deeper area of elevated foam cell lesions of elastic arteries. Ultrastructural observation confirmed the presence of monocytes in the intima, their differentiation into macrophages, and their transformation into foam cells in the atherosclerotic lesions. lmmunohistochemical expression of MCSF was demonstrated in the endothelial cells, smooth muscle cells and foam cells. A minor macrophagederived foam cell population was demonstrated to possess a prolif-erative capacity. These data suggest that MCSF is involved in the differentiation of monocytes into macrophages, their transformation into foam cells, and their proliferation during pulmonary atherogenesis. 相似文献