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氟苯咪唑(Fludendazole)由Gelder于1969年合成,直到最近几年才受到各国重视,我国于1983年也合成了该化合物。该药经临床应用疗效显著,抗虫效力高,抗虫谱  相似文献   
3.
The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems.  相似文献   
4.
东茛菪碱五个剂量(1、2、5、10、20μg/ml作用于12名健康成人外周血淋巴细胞培养液诱发染色体畸变,并设空白对照组(生理盐水)。染色体畸变率分别为3.±0.5,9.6±1.1,11.7±1.1,13.6±2.3,18.0±3.0和17.5±2.0%;细胞畸变率为3.1±0.6,9.2±0.6,10.0±0.8,10.8±1.5,11.6±1.8和12.2±14.%。各剂量组与对照组比较差异高度显著(P<0.01)。方差分析,各剂量组间变异的差异高度显著(P<0.01)。相关系数和回归系数也非常显著(P<0.01)。结果表明,东莨菪碱剂量与染色体畸变率和细胞畸变率有线性关系。  相似文献   
5.
132例男性不育患者遗传学病因分析   总被引:3,自引:0,他引:3  
目的:对男性不育患者进行遗传学病因分析,并探讨其遗传效应。方法:采取132例男性不育患者外周血进行染色体核型分析。结果:132例男性不育患者中,染色体异常24例,染色体变异22例。其中大Y20例,47,XXY18例,45.XY,t(13;14)3例,小Y和46,XY,inv(9)各2例,46,XY,t(9;22)1例。结论:染色体异常是男性不育的重要原因,并建议男性不育患者进行基因诊断,以便确诊是否属于遗传病,为生育提供指导,避免盲目治疗。  相似文献   
6.
目的分析1组Goldenhar综合征家系的临床表现及遗传学特征。方法我们随访到1组4代33人的Goldenhar综合征家系,对目前存活的29人进行了临床表型和遗传学的初步分析。结果家系内有Goldenhaar综合征患者5人.临床表现具高度多样性,累及眼、耳、脊柱、颜面、口腔等多个器官和系统的发育不良,在遗传方式上属于常染色体显性遗传。从细胞遗传学水平对家系中成员进行染色体检查,未发现核型异常。结论该Goldenhar综合征家系属常染色体显性遗传,染色体检查未发现核型异常。  相似文献   
7.
The aim of this study was to assess the shaping ability of the M4 reciprocating handpiece and Safety Hedstrom files in simulated canals. A total of 40 simulated canals of various angles and positions of curvature were prepared with an M4 handpiece using Safety Hedstrom files oriented with the ground, flattened surface towards the inner aspect of the curve. A standard regimen was adopted throughout. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount and location of resin material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Preparation time varied significantly (P<0.001) between the canal types; overall, 20° canals were prepared more quickly than 40° canals. Zips and elbows were observed in 16 out of the 40 canals with most (11) being created in 40° specimens. Ledges were found in 19 canals and perforations in only 1. There were no significant differences between canal shapes for these aberrations. Excessive removal of material from the inner aspect of the canal at the curve to create a danger zone was found in 20 canals, but only in those with 40° curves. Significant differences in total canal width between the canal types were seen at the zips (P<0.05), elbows (P<0.05) and danger zones (P<0.001). Transportation at the danger zones varied significantly (P<0.001) between canal types. Under the conditions of this study, the M4 handpiece and Safety Hedstrom files created hour-glass preparations in a substantial proportion of canals. In reality, the Safety Hedstrom file with its one flattened surface was ineffective at reducing removal of material along the inner aspect of canal curves in severely curved specimens and clearly has the potential to create strip perforations in teeth.  相似文献   
8.
The various causative and mechanistic phenomena associated with aneuploidy induction require considerable investigation to better understand the etiology of chromosome missegregation. We investigated the potential of vinblastine sulfate, pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate to induce numerical and structural chromosome changes in female mouse germ cells. Superovulated ICR mice were administered the compounds either by intraperitoneal injection or oral gavage, and oocytes were collected and processed for cytogenetic analysis 17 hr later. Vinblastine sulfate, administered i.p., induced a significant increase in the frequency of ovulated Ml oocytes and of hyperploid Mll oocytes compared to controls, but did not increase the frequency of structural aberrations. Pyrimethamine, diethylstilbestrol diphosphate, and chloral hydrate did not increase the frequency of numerical or structural chromosome changes in female mouse germ cells. © 1993 Wiley-Liss, Inc.  相似文献   
9.
中国汉族人群腓骨肌萎缩症Cx32基因突变分析   总被引:7,自引:0,他引:7  
Charcot Marie Tooth (CMT)diseaseisthemostcommoninheritedperipheralneuropathywithapreva lenceof 1in 2 5 0 0 .Distalmuscleweaknessandatro phy ,sensorylossandreducedorabsenttendonreflex es ,pescavus ,hammertoes ,steppagegaitareamongthemainsymptoms .Thereares…  相似文献   
10.
目的:研究无精子症和严重少精子症患者染色体畸变及Y染色体(Yql1区)无精子症因子(azoospermic factor,AZF)缺失情况,建立Y染色体微缺失的临床筛查方法。方法:对134例患者(无精子症97例,严重少精子症37例)经染色体核型分析及AZF、区三个位点8对引物PCR扩增,检测染色体畸变和Y染色体微缺失率。结果:134例中染色体核型异常9例,占6.72%。AZF缺失18例,缺失率为13.43%。无精子症和严重少精子症AZF、缺失率分别为14.43%、10.81%。结论:染色体畸变和Y染色体微缺失是导致无精子症和严重少精子症的主要原因之一。无精子症缺失率高于严重少精子症患者。AZF区三个位点8对引物PCR扩增可作为Y染色体微缺失的临床筛查方法。  相似文献   
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