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1.
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   
2.
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   
3.
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   
4.
氯丙嗪和氯氮平对小鼠生殖细胞和人淋巴细胞的诱变效应   总被引:1,自引:0,他引:1  
为探讨氯丙嗪和氯氮平在使用临床治疗剂量时的遗传毒理效应,研究了两药对小鼠生殖细胞和小鼠子代体细胞的影响,以及对人体淋巴细胞姊妹染色单体互换(SCE)频率及微核率的影响。结果显示:(1)连续给药5天后第1周两药高、中、低三个剂量组均能引起小鼠精子头部畸形率明显增高,但停药4周后对精子的致畸作用基本消失;(2)两药对小鼠睾丸细胞及子代体细胞的染色体结构畸变率均无明显影响;(3)两药在治疗剂量时对人淋巴细胞的SCE频率及微核率无明显影响,治疗前后的自身对照研究亦未见两频率有明显改变;(4)两药的血药浓度与SCE频率及微核率之间无量效关系。研究结果提示,两药在临床治疗剂量时对小鼠生殖细胞染色体结构以及对人体遗传物质均无明显损伤作用。  相似文献   
5.
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   
6.
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   
7.
Chromosomes in 1620 metaphases of ascitic fluid cells in 20 cases of ovariancarcinoma were analyzed.The results showed that there were marked structuralaberrations aside from significant increase in chromosomal numerical aberrations(85.2%).In the ascitic fluid cells from 12 patients,15 types of marker chromosomes were found,among which t(6;14)(q21;q24)and t(2;6)(q35;p12)were more frequently noted witha rate of 7.84% and 7.59% respectively,which was significantly higher than that of othermarker chromosomes(P<0.01).The findings suggested that,besides t(6;14)(q21;q24),t(2;6)(q35;p12)may also be a specific marker chromosome of ovarian carcinoma.  相似文献   
8.
对134Cs诱发体细胞和生殖细胞的畸变效应进行了比较研究。方法观察内污染不同放射性活度134Cs时诱发同体骨髓细胞和精原细胞染色体畸变的量效关系,以及同一放射性活度134Cs作用不同时间诱发上述两种细胞的染色体畸变产额。结果研究发现,134Cs内照射诱发的骨髓细胞染色体畸变产额显著高于精原细胞,而其诱发的染色体畸变类型均以染色单体型畸变为主。结论由不同放射性活度134Cs所诱发的染色体畸变产额而言,骨髓细胞要比精原细胞高出1.5~5倍。  相似文献   
9.
应用常规染色体畸变分析和胞浆分裂阻滞微核(cytokinesisblockmicronuclei,CBMN)法对10例接受单次卡铂(平均剂量为462.9mg/m2)和单次阿霉素(平均剂量为48.1mg/m2)化疗的乳癌病人血样进行了淋巴细胞染色体畸变(chromosomeaberation,CA)和微核(micronuclei,MN)的观察分析,并通过有丝分裂指数(mitoticindex,MI)及核分裂指数(nucleardivisionindex,NDI)观测了细胞毒性。结果表明,单次卡铂和阿霉素化疗均引起了CA和MN显著性增加,所观察到的CA主要为单体畸变,其中单体间隙(chromatidgap,ctg)的增加最为显著,染色体型畸变未见显著性变化;卡铂引起MI明显减低,阿霉素对MI的影响不显著;两种化疗药物均未对NDI产生显著性影响;通过MI及NDI测量的细胞毒性之间显著性相关,但CA分析和CBMN法测得的染色体损伤之间缺乏相关性。  相似文献   
10.
应用细胞遗传学和皮纹分析方法对142例先天性智能发育不全患儿进行了研究。其中,120例正常核型,22例异常核型。异常核型46,XY,t(1;3;21)(1pter→1q32.1∶∶21p11.2→21qter;3 qter→3p26.2∶∶1 q32.1→1 qter)和45,X/45,X,-22,+der(22)t(Y;22)(22qter→22p11.1∶∶Yq11.1→Yq11.2)两种核型国内尚未见报道。皮纹分析结果表明56.7%的患者有1项以上异常皮纹;染色体异常患者均有2项以上异常皮纹;先天愚型患者有“特定”的皮纹改变。  相似文献   
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