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21.
AnAnalysisofChromosomeonSterilityCausedbyAzoospermiaorOligospermia¥WuMeiheng;TangWingnuo.(ACTAACADEMIAEMEDICINAENANJING,1995(...  相似文献   
22.
The purpose of this study was to assess the impact of an educational intervention on medical students' attitudes toward social and sexual contact with patients by doctors from three medical specialties (general practice, obstetrics/gynaecology and psychiatry). Medical students from two consecutive fifth year classes at one medical school participated in one 3 hour session that included instruction on the standards of the profession that prohibit doctor–patient sexual contact. Students were assigned to either intervention groups or control groups and responded to an anonymous questionnaire (overall response rate 66·8% ; n=141). As many as 14·5% of control group students thought it was (sometimes or usually) appropriate for general practitioners to date their own patients and at least 3% thought it appropriate for members of any of these three medical specialties to engage in sexual contact with their own patients. However, there were no significant differences in attitudes toward hugging, dating or sexual contact with current patients between those who had attended the seminar and the control groups. The session significantly influenced attitudes regarding obstetrician/gynaecologists and psychiatrists hugging and having sexual contact with former patients. These findings are discussed in relation to a need for expansion of such instruction.  相似文献   
23.
The effects of gonadal steroids on GABA-, taurine (TAU)- and N-methyl-D, L-aspartate (NMA)-induced gonadotropin-II (GTH-II) release were investigated in male and female goldfish in vivo. In sexually regressed goldfish (both sexes mixed), intraperitoneal implantation for 5 to 10 days with solid Silastic pellets containing testosterone (100 μg/g), oestradiol (100 μg/g) or progesterone (100 μg/g) was previously shown to elevate serum sex steroid levels to values comparable to those in sexually mature animals, and to potentiate gonadotropin-releasing hormone-stimulated GTH-II release. In the present study, testosterone but not oestradiol or progesterone enhanced the stimulatory effects of exogenous GABA (100 μg/g) on GTH-II release in vivo. TAU (1 mg/g) stimulated GTH-II release in sexually regressed mixed sex and sexually recrudescent male goldfish, and both testosterone and oestradiol implantation enhanced GTH-II release induced by TAU. The glutamate agonist NMA (25 to 50 μg/g) was also found to stimulate GTH-II release; however it was relatively less effective in elevating serum GTH-II levels than GABA and TAU, and its effects were not modulated by sex steroid treatments. Pretreatment of goldfish with α-methyl-p-tyrosine to deplete brain and pituitary catecholam-ines did not affect NMA action on GTH-II release. Our results indicate that GABA, TAU and NMA are involved in the neuroendocrine regulation of GTH-II release in goldfish, and support the idea that testosterone participates in the positive feedback regulation of pituitary gonadotropin release in a non-mammalian vertebrate by enhancing GABA- and TAU-stimulated GTH release in vivo.  相似文献   
24.
A longitudinal study of semen quality in pesticide spraying danish farmers   总被引:9,自引:0,他引:9  
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones.  相似文献   
25.
1600例住院病人死亡原因分析   总被引:1,自引:0,他引:1  
[目的 ]探讨 160 0例住院病人的死亡原因及其分布特征 .[方法 ]收集 1995年 1月至 2 0 0 2年12月间 160 0例我院住院死亡病人资料 ,对死亡疾病构成比率、男女主要疾病死亡构成比率、汉族和朝鲜族主要疾病死亡构成比率及年龄构成比率进行统计 .[结果 ] 160 0例死亡病例的死亡原因中脑血管疾病占 2 4 9% ,恶性肿瘤占 2 3 4% ,消化系统疾病占 13 7% ,意外伤害和中毒占 10 3 % ,心血管疾病占9 2 % ;男性与女性主要疾病死亡分布不同 ,两者间有非常显者性差异 ;汉族与朝鲜族主要疾病死亡分布不同 ,两者间亦有非常显者性差异 ;年龄构成比中 61~ 70岁居首位 ,占 2 6 6% ,51~ 60岁占 18 0 % ,41~ 50岁占 16 8% ,71~ 80岁占 15 8% ,3 1~ 40岁占 10 8% .[结论 ]住院死亡的疾病构成因性别及民族不同 ,其分布不同  相似文献   
26.
分娩时子宫下段MMP-9及其组织抑制剂TIMP-1的变化   总被引:1,自引:1,他引:0  
目的:探讨基质金属蛋白酶(MMP)及其组织抑制剂(TIMP)在分娩发动、宫颈成熟和扩张中的作用和机制.方法:采用ELISA方法测定子宫下段组织中MMP-9和TIMP-1的浓度.有宫缩剖宫产组56例,其中第一产程组44例,第二产程组12例.以无宫缩剖宫产组16例为对照组.结果:有宫缩剖宫产组子宫下段组织中MMP-9和TIMP-1的浓度分别明显高于无宫缩剖宫产组(P<0.05,P<0.05).第一产程组中随宫口开大,MMP-9和TIMP-1的浓度各组间无显著性差异.第二产程组MMP-9和TIMP-1的浓度分别明显高于第一产程组(P<0.01,P<0.05).结论:MMPs和TIMPs的动态变化是分娩发动、宫颈成熟和扩张过程中的重要中间环节.  相似文献   
27.
28.
A morphometric analysis of the developing organ of Corti and its component hair cells was carried out in an age-graded series of Syrian golden hamsters with the aid of scanning electron microscopy. The purpose was to establish a quantitative framework that would provide insight into the rules and principles by which the mammalian cochlea attains its adult proportions. This study examined postnatal development at two day intervals from birth to 22 days after birth. Our analysis included measures of cochlear length and hair cell numbers as well as measures of hair cell sizes in each of five sectors along the cochlear spiral. Our results demonstrate several principles of cochlear development: (1) The full two and one-fourths turns seen in the adult cochlea are already present at birth, but the cochlea continues to elongate for the next 10–12 days. (2) Development of hair cells in the apex generally lags behind that in the base. Whereas the stereocilia and apical margins of hair cells are clearly defined in the basal turn, they become well defined in the apex only postnatally. (3) Growth in cochlear length occurs mainly by increases in cell size rather than in cell numbers; although hair cells do increase in numbers during the first 4 days of cochlear growth, this increase involves addition of hair cells only to preexisting regions of the cochlear apex. Moreover, the full complement of hair cells is established 6 days before the full size of the cochlea is attained; in contrast, hair cell growth occurs at all positions along the cochlear spiral and spans the entire period of cochlear elongation. (4) The period of hair cell growth exceeds the period of organ of Corti growth and appears to be possible by decreases in intercellular spacing, primarily in the apical region of the cochlea; inner and outer hair cell growth was complete between 16 and 18 days after birth. (5) Inner and outer hair cell neighbors remain virtually constant at different ages indicating that the spatial relationships between the two hair cell populations is preserved as the cochlea grows. (6) Comparison with previous developmental studies of auditory function in the hamster reveals that the age of 16 days after birth, when hair cells attain their mature sizes, coincides with the onset of brainstem auditory evoked responses. Growth of hair cell somas alone, however, cannot explain either the subsequent maturation of evoked potential thresholds or changes in frequency representation in the developing cochlea. © Wiley-Liss, Inc.  相似文献   
29.
不同性别飞行学员人格特征的比较   总被引:3,自引:2,他引:1  
目的 :探讨男女飞行学员人格特征的差别 ,为选拔战斗机女飞行员提供心理选拔方法的参照 .方法 :女学员组为某飞行学院 2 2名女飞行学员 ,男学员组为同一飞行学院 4 3名男飞行学员 .采用卡特尔 16种个性因素测验 (16PF) ,应用DXC多项心理测评仪进行集体测试 .结果 :在 16PF的 2 4个分析项目中 ,情绪的稳定性 (C)、兴奋性 (F)、敢为性 (H)、怀疑性 (L)、紧张性 (Q4)、适应与焦虑、内向与外向等 7个因子分男学员和女学员有显著差异 (P <0 .0 5或P <0 .0 1) ,其中在稳定性、兴奋性、敢为性和外向性等 4个因素上 ,女学员的分数显著高于男学员 (P <0 .0 5或P <0 .0 1) ;而在怀疑性、紧张性、焦虑性等 3个因子分上则是男学员显著高于女学员(P <0 .0 5或P <0 .0 1) .结论 :女飞行学员的个性特点是情绪稳定 ,轻松兴奋 ,冒险敢为 ,适应环境 ,趋于外向 ,紧张困扰和焦虑较少 .本调查结果表明 ,女飞行学员的人格特征基本符合战斗机飞行员人格结构的要求  相似文献   
30.
Objectives: Previous studies have been inconsistent with regard to the extent to which stress perception, rather than stressor exposure, predicts negative health symptoms. Because sex differences have been observed in all three of these variables, in this study the possibility that sex differences also exist in the relationships between them is investigated. Methods: Self‐report inventories of perceived stress, stressor exposure, and negative health symptoms were given to 107 young‐adult participants (65 females, 42 males). Results: Sex differences were observed in the associations among perceived stress, stressor exposure, and negative health symptom rates. Specifically, while higher perceived stress and higher stressor exposure rates independently predicted higher negative health symptoms rates in females, only higher stressor exposure rates independently predicted higher negative health symptoms in males. Indeed, unexpectedly, after controlling for exposure to stressors there was a trend towards higher perceived stress predicting lower negative health symptoms in males. Conclusions: While exposure to stress was a significant negative predictor of health for both sexes, perception of stress was predictive only for females. One implication of this finding is that different psychological models are needed to predict health symptoms in the two sexes. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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