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1.
丙烯腈对雄性ICR小鼠生殖细胞毒性   总被引:3,自引:1,他引:2  
目的:探讨丙烯腈对雄性小鼠生细胞的毒性作用。方法:雄性ICR小鼠以0、2.5、5、10mg/kg体重剂量连续腹腔注射染毒5d,2周后处死动物,观察睾丸中早期精细胞微核;ICR雄性小鼠以0、6、12、24mg/kg体重连续灌胃染毒5d后于每周末处死部分动物。连续5周,分析附睾精子畸形率。结果:早期精细胞微核实验结果表明,染毒剂量≥5.0mg/kg,早期精细胞微核明显增加,微核率与染毒剂量之间存在剂量  相似文献   

2.
采用Tates微核试验法检测3种无机化学物对雄性小鼠生殖细胞染色体的损伤作用。不同剂量的氟化钠(14mg/kg、28mg/kg)、氯化汞(0.5mg/kg、1.0mg/kg)和亚砷酸钠(0.25mg/kg、0.5mg/kg)分别经腹腔注射染毒,每天1次,连续3天,于首次染毒后第15天杀鼠。测得微核率为7.2%,10.0‰;6.4‰、5.6‰和3.4‰、3.0‰。其中氟化钠和氯化汞组的微核率与阴性对照组(2.2‰)比较.有显著差异.可以认为是雄性生殖细胞染色体断裂剂。根据染毒到制片的间隔时间判断,氟化钠和氯化主要作用于减数分裂前的G1和S期初级精母细胞。  相似文献   

3.
研究氢醌对小鼠和大鼠的急性毒性和蓄积毒性,为建立卫生标准提供资料。方法:选用昆明种小鼠60只,S.D雌性小刀30只,以氢醌乳化液,分别按0-900mg/kg和0-2150mg/kg各分5个剂量组,一次性灌胃染毒。选用昆明种小鼠50只,S.D雌性大鼠25只,以HQ乙醇溶液,分别按0-3840,g/kg各分5个剂量组一次性皮肤涂布染毒;另选昆明种小鼠40只,以剂量定期递增染毒法灌胃,起始染毒剂量为0.  相似文献   

4.
硝基苯对小鼠睾丸细胞酶的作用   总被引:2,自引:0,他引:2  
以剂量为100mg/kg体重、500mg/kg体重的硝基苯(NB)分别给雄性小白鼠经口染毒。染毒2天后,各染毒组的睾丸组织中G-6-PD、LDH-x、SDH的活性均明显低于对照组。染毒4天后,染毒组G-6-PD活性恢复到对照水平;LDH-x的100mg/kg体重组恢复到对照水平,而500mg/kg组仍明显低于对照组;SDH活性染毒组仍低于对照组。LPO值在染毒2天、4天后与对照组相比均无显著差异。  相似文献   

5.
钼和汞联合染毒对小鼠骨髓多染红细胞微核率影响   总被引:3,自引:0,他引:3  
[目的]探讨对钼对汞遗传毒性的影响。[方法]观察采用腹腔注射钼酸钠和氯化汞联合染毒对小鼠骨髓多染红细胞微核率的影响。[结果]连续4天给小鼠注射HgCl2[1.0mg/kg(bw)]的同时注射10、100mg/kg(bw)]的Na2MoO4可显著降低HgCl2的致小鼠微核率(P〈0.001);在HgCl2[1.0mg/kg(bw)给小鼠染毒前3天连续注射100mg/kg(bw)Na2MoO4可显著地  相似文献   

6.
砷诱发细胞凋亡与大鼠畸胎形成的关系研究   总被引:12,自引:1,他引:11  
李勇  俞在芳 《卫生研究》1998,27(2):91-94
为进一步揭示砷的致畸性、胚胎毒性和作用机制,采用胚胎活体染色和原位DNA末端标记等技术探讨了不同剂量砷是否能诱导孕9.5天龄大鼠的胚胎细胞发生凋亡(程序性细胞死亡)及其凋亡与畸胎形成的关系。结果表明随着砷浓度(0、1、4和8mg/kg)的增高,畸胎率和死胎率分别由2.6%和0上升到35.7%和23.8%,呈明显剂量-反应关系。活体染色发现在胚胎脑、眼、体节、肢芽和腮弓等部位出现大量散在的凋亡细胞,与畸形发生部位相一致。原位DNA末端标记进一步证实砷能诱发器官形成期胚胎细胞凋亡,8mg/kg砷染毒后,凋亡阳性率高达55.6%(P<0.05),表明凋亡与畸胎发生关系密切,这是砷致畸作用的重要机制之一。实验结果还发现胚胎细胞坏死亦与畸胎形成有关。  相似文献   

7.
观察氯化锂的遗传毒性特征并对其毒作用机制做一初步探讨。以氯化锂为受试物,昆明种小鼠为受试对象,分低(22.5mg/kg)、中(75.0mg/kg)、高(225.0mg/kg)3个不同剂量组进行小鼠体细胞遗传毒性试验。氯化锂经口灌胃染毒后,小鼠骨髓细胞染色体畸变率增高(P〈0.05);骨髓细胞微核率、胎肝细胞微核率增高(P〈0.05,P〈0.01)。结果表明,一定剂量的氯化锂对昆明种小鼠体细胞具有遗  相似文献   

8.
选用Wistar大鼠对雪山蚁皇胶囊进行了致畸性研究,雪山蚁后胶囊设三个剂量组:2、4、6g/kg体重,同时设蒸馏水对照组,采用经口给药。结果:三个剂量组孕鼠体重增长、吸收胎率、死胎率和各组活胎的身长、尾长、体重和对照组比较差异均无显著性(P〉0.05),胎鼠的生长发育及内脏和对照组比较差异均无显著性(P〉0.05)。提示雪山蚁后胶囊在6g/kg体重以下均未见有母体毒性和胚胎毒性反应及致畸性,致畸危害指数大于300,表明对人体危害小。  相似文献   

9.
氯化镉对小鼠腹腔巨噬细胞功能的影响   总被引:8,自引:1,他引:7  
目的观察镉对巨噬细胞功能的影响。方法以0.3、0.6、1.2mg/kg体重CdCl2连续给小鼠灌胃14天后进行巨噬细胞吞噬功能、产生NO的能力及产生H2O2等多个指标的检测。结果在各剂量CdCl2作用下,小鼠腹腔灌洗液细胞数减少,与对照组比差异有显著性。巨噬细胞吞噬功能受到明显抑制,抑制率分别为21.8%、39.9%、44.4%,且呈现剂量反应关系(r=-0.9031)。巨噬细胞产生NO的能力也受到明显抑制,对照组为76.10±14.22μmol/L,其于各组分别为61.90±27.83、3667±23.86、46.60±13.33μmol/L。巨噬细胞产生的O-2在三种剂量下都出现明显抑制,呈现剂量反应关系(r=0.9790)。巨噬细胞产生H2O2的能力仅在1.2mg/kg剂量时出现明显抑制,与对照组比差异有显著性,但H2O2的产生与CdCl2剂量亦存在剂量反应关系(r=-0.9847)。结论CdCl2在03、0.6、1.2mg/kg剂量下对巨噬细胞吞噬功能,NO、O-2、H2O2等生物分子的产生均有明显抑制。因此认为CdCl2可直接影响巨噬细胞的抗原递呈及非特异性防御功能  相似文献   

10.
氯化甲基汞对卵巢细胞酶及其线粒体的影响   总被引:2,自引:0,他引:2  
用氯化甲基汞(以1/200LD50、1/20LD50和1/2LD50即0.1925mg/kg、1.925mg/kg和19.25mg/kg体重的剂量)给昆明种雌性小鼠经口染毒,然后测定卵巢细胞中的LDH、G-6-PD和SDH活性,同时做卵巢细胞线粒体的电镜观察。结果表明:各剂量组的LDH、G-6-PD活性明显低于对照组(P<0.05)。1/2LD50和1/20LD50组的SHD活性也明显低于对照组(P<0.05)。从电镜看到线粒体膜较完整,但在1/2LD50和1/20LD50组中的线粒体嵴数目减少,甚至完全消失,基质呈空泡状改变。总之,酶活性改变,能量代谢的异常和线粒体的损伤可能是氯化甲基汞造成卵巢细胞功能改变的重要原因。  相似文献   

11.
Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.  相似文献   

12.
This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.  相似文献   

13.
Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L?1 to a maximum of 79?mg·L?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.  相似文献   

14.
深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.  相似文献   

15.
Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO2) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO2. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO2 at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO2 gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO2 also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO2.  相似文献   

16.
Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).  相似文献   

17.

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.  相似文献   

18.
19.
Occupational health hazards in mining: an overview   总被引:1,自引:0,他引:1  
This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.  相似文献   

20.
This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.  相似文献   

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