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121.
122.
职业接触氯乙烯对生殖功能影响的调查 总被引:4,自引:0,他引:4
Huang Mei-yuan Institute of Occupational Medicine Chinese Academy of Preventive Medicine Beijing 《中华劳动卫生职业病杂志》1994,12(1):12-15
对全国12个城市中13个聚氯乙烯制造工厂中2736名接触氯乙烯的工人及3442名对照厂工人,进行了生殖功能的流行病学调查研究,结果表明,接触氯乙烯男、女工人的各项生殖结局指标与对照组比较无显著性差异,但女工氯乙烯接触组妊娠合并症的发生率明显高于对照组,表明氯乙烯对女工的妊娠过程有一定影响,因此积极改善劳动条件,不仅对保护工人健康,而且对保护其子代的正常发育成长也有重要意义。 相似文献
123.
高频电磁场对工人行为功能的影响 总被引:6,自引:0,他引:6
采用世界卫生组织推荐的神经行为核心测试组合(WHO-NCTB),对高频作业工人41名(平均工龄13.9a(年)及年龄、性别、文化程度与接触组相匹配的对照组工人39名(平均工龄13.3a)分别进行了行为功能测试。结果表明高频作业工人部分情感状态得分和某些行为功能得分与对照组相比差异有显著性。长期接触高频电磁场可能引起工人情感状态改变,记忆力减退、注意力分散及心理运动稳定度下降。 相似文献
124.
本研究采用先进的三维超声成像技术及多普勒技术对正常育龄妇女月经周期中心血管功能进行研究。结果:月经周期中HR、BP无变化;血清E2是周期性变化,排卵前达高峰。SV、CO、EF在排卵前期升高达峰值,显著高于月经期和黄体期;SVR排卵前期最低,而Ved、Ves无变化。Vmax、A、E在内源性E2高峰时明显加快,而E/A比值无明显变化。结果提示:月经周期中随内源性E2的周期性变化,心脏功能也发生周期性变化。E2高峰时,心输出量、心搏量和射血分数达最高。外周阻力最低,心脏内血流速度加快。 相似文献
125.
In a cohort of 3383 men aged 53 to 74 in the Copenhagen Male Study we investigated the association between ischaemic heart disease (IHD) and the Lewis blood group, assigned to chromosome 19. Among men with the Le(a-b-) phenotype, 8% had a history of non-fatal myocardial infarction, among others the frequency was 4%. The corresponding odds ratio was (95% confidence interval: CI) 1.9 (1.2-3.0) P < 0.01, men with Le(a-b-) had a risk-factor profile and pattern of disease resembling that of Reaven's syndrome X. In a subsequent prospective study 343 men with arteriosclerotic stigmas were excluded. The men had their morbidity and mortality recorded over the next 4 years. One-hundred-and-one men suffered IHD; 26 dying from IHD. In total 162 men died. Men with Le(a-b-) had an increased risk of death from IHD compared with others. Adjusted for age, relative risk (RR) (95% CI) was: 4.4 (1.9-10.3), P < 0.001, and for all causes of mortality: RR = 1.6 (1.0-2.6), P < 0.05. Men with the Le(a-b-) phenotype had an increased risk of an IHD event compared to men with other phenotypes (RR = 1.6 (0.9-2.8), P = 0.10) and a significantly higher IHD case fatality rate (RR = 2.8 (1.5-5.2), P = 0.01). The finding that the Le(a-b-) phenotype is a genetic marker of IHD risk may have implications in terms of prevention. The Le(a-b-) phenotype may also contribute to providing an explanation for the substantial ethnic differences found in the incidence of IHD. The similar risk-factor profile and pattern of disease found between Le(a-b-) men and individuals with Reaven's syndrome X is hypothesized to be due to a close genetic relationship on chromosome 19. 相似文献
126.
Mnica De la Fuente Juan Jos Garrido Rosa María Arahuetes Angel Hernanz 《Journal of neuroimmunology》1993,42(1)
The neuropeptides neurotensin and neuromedin N (from 10−12 M to 10−9 M) have been showed in this study to stimulate significantly in vitro several steps of the phagocytic process: adherence to substrate, chemotaxis, ingestion of inert particles (latex beads) and production of superoxide anion measured by nitroblue tetrazolium reduction in resting peritoneal macrophages from BALB/c mice. A dose-response relationship was observed, with a maximal stimulation of the phagocytic process at 10−11 M. The two neuropeptides induced no change of intracellular cyclic AMP in murine macrophages. Moreover, adherence and chemotaxis decreased significantly in the presence of EGTA (1 mM), a chelator of extracellular Ca2+, or ryanodine (0.5 mM), a blocker of a Ca2+-gated channel from the endoplasmic reticulum, in both controls and samples with the addition of neurotensin or neuromedin N. These results suggest that there is no relation between the cAMP messenger system and the phagocytic process stimulation in murine peritoneal macrophages by neurotensin or neuromedin N. In addition, the results observed with EGTA and ryanodine could indicate that these two neuropeptides produce their effects through an increase of intracellular Ca2+ concentration. 相似文献
127.
分别采用联合火箭免疫电泳技术和酶法对49例冠心病患者和50例健康人血清载脂蛋白 A_1(apoA_1),载脂蛋白 B_(100)(apoB_(100)),以及血清总胆固醇(TC)、甘油三酯(TG),高密度脂蛋白胆固醇(HDL—ch)的含量进行了测定。结果冠心病患者血清 apoB_(100)(0.99±0.26g/L)明显高于健康人(0.62±0.18g/L);而apoA_1/apoB_(100)比值(1.22±0.35)则明显低于健康人(2.12±0.49);TC,TG,HDL-ch 的含量亦有统计学意义。提示,在预示冠心病危险因素的各种脂类及脂蛋白中,以 apoB_(100)增高 apoA_1/apoB_(100)比值降低最为灵敏,最为准确,且高于单纯测定TC,TG 和 HDL-ch。 相似文献
128.
Treatment of rat heart grafts with PUVA, the combination of the photosensitizer 8-methoxypsoralen and longwave ultraviolet light, leads to a prolonged transplant survival in allogeneic recipients. A PUVA treatment of the recipient rats, performed for 7 consecutive days after transplantation, prolonged graft survival even more effectively. This may be due to the systemic immunomodulatory effects of PUVA in the recipient. One of the mediators is urocanic acid, which is transformed by ultraviolet light in the skin from its trans- to the cis-isomer, which, in turn, acts as a mediator on the immune system. An injection of cisurocanic acid into graft recipients for 7 consecutive days after transplantation resulted in prolonged graft survival; in 40% of the rats, permanent graft acceptance was observed. The significance of these results for clinical organ transplantation is discussed. 相似文献
129.
130.
David Langton Diana Way Lisbeth Trigg Duncan Blake Barry McGrath 《Clinical and experimental pharmacology & physiology》1990,17(3):219-223
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process. 相似文献