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31.
A previous study showed that adult female dancers have a high percentage of type I fibres in vastus lateralis. similar to that of endurance-trained female runners ar female cross-country skiers. It is not known if dancers already at an early age are characterized by a high percentage of type I fibres or develop a high percentage of type I fibres as a consequence of dance training. Furthermore. the muscle fibre composition of male dancers has not previously been studied. Therefore the aim of the study was to analyse skeletal muscle fibre characteristics in 10-year-old and 20-year-old dancers of both sexes. Age-matched boys and girls whose physical activity was average for their age groups served as controls. Muscle biopsies for histochemical analysis were obtained from vastus lateralis using the percutaneous needle technique. The major finding of the present study was that the vastus lateralis of young dancers of both sexes had a higher percentage of type I fibres than that of controls. Moreover. the higher type I percentage was seen not only in 20 year aids. but also in 10 year aids. who had begun their dance training at a professional level only a few weeks earlier. No significant difference in this respect was found between female and male dancers. In conclusion. the muscle fibre type composition in young dancers of both sexes differs from that of the average individual of the same age and is characterized by a high percentage of type I fibres.  相似文献   
32.
In this century, the use of pesticides and fertilizers (agrochemicals) is indispensable because they are seen as a panacea for protecting crops from insects and diseases. However, the manner in which these agrochemicals are handled poses significant health risks to manufacturers, transporters, vendors and farmers. In Kenya, for example, coffee factory workers (specifically storekeepers) apportion the agrochemicals and sell them to the coffee farmers. The process of apportioning and other factors expose these workers to health risks. In order to evaluate the extent of the problem, a pilot study was undertaken in the Githuguri location. The results showed that lack of use of protective clothing, poor handling of agrochemicals and poorly designed storage facilities were very common. As a result, 95% of the workers interviewed reported a variety of agrochemical health related problems. In conclusion, the government and the public role regarding possible preventive measures were proposed.  相似文献   
33.
SRY基因诊断在临床中的应用   总被引:1,自引:0,他引:1  
应用聚合酶链式反应(PCR)扩增技术,对10例染色体核型为46,XY和1例为46,XX/46,XY的性反转、睾丸女性化、两性畸形及男性生殖器发育不良的患者进行了性别决定区(SRY)基因检测。结果表明9例46,XY和1例46,XX/46,XY患者的SRY基因存在,1例46,XY女性患者的SRY基因缺失。该结果表明能够用分子生物学技术对性反转、性发育异常的病因进行分析  相似文献   
34.
Sex-specific effects for body mass index (BMI) were explored in a newly established, population-based Norwegian twin panel. The sample includes 5,864 individuals, aged 18–25 years, who responded to a questionnaire containing items for zygosity classification, height, weight, health, health-related behaviors, well-being, and demographic information. Among the 2,570 intact pairs who returned the questionnaire there were 416 identical (MZ) male pairs, 387 fraternal (DZ) male pairs, 528 MZ female pairs, 443 DZ female pairs, and 796 unlike-sexed pairs. Alternate sets of models testing for either sex-specific genetic or environmental parameters were evaluated using structural equation analysis. Results from the most parsimonious model indicated that the genes contributing to variation in BMI are not identical for men and women; rather, some genetic effects were shared by the sexes and some were unique to each sex. Total variation in BMI could be explained by sex-specific additive genetic effects, as well as genetic and non-shared environmental effects common to men and women. Estimates of heritability were .708 for men and .789 for women, and the male-female genetic correlation was 0.622. The series of models specifying sex-specific shared environment also fit the data and suggests that shared environmental factors may be important for males but not for females. The findings raise questions concerning the relationship between sex-specific effects for BMI and sex differences in health outcomes. ©1995 Wiley-Liss, Inc.  相似文献   
35.
A file review of 178 male patients with sexual dysfunction revealed that high income, married status, presence of partner at evaluation, and liberal attitude towards sexuality increased the chances of selection for behavioral sex therapy. The outcome of therapy was associated with treatment adherence. Participation of the conjoint unit resulted in lower dropout rates.  相似文献   
36.
Summary: Summary. A study was conducted to determine whether the attitudes of medical students to death and caring changed during the 3 months following exposure to cadaver dissection. All first-year students were invited to complete a questionnaire immediately before their initial cadaver dissection experience, after 6 weeks, and after a further 3 months. The questionnaire reflected attitudes to death, violent death, death of someone known to the respondent and caring when someone known to the respondent is seriously injured. Ethnicity and previous exposure to dying has no effect on responses, but overall men students' reactions were significantly less than for women ( P < 0.001). The responses given on the final part of the questionnaire after 3 months were significantly lower than those to most questions in the first part of the questionnaire. The exceptions were those questions where the subject in the given scenario was known to the respondent, where reactions were rated significantly greater ( P < 0.001) in the follow-up questionnaire and can be explained on the basis that they were a personal referent.
Students rapidly develop a coping mechanism which enables them to view cadaver dissection as an occupation quite divorced from living human beings. During these early months of training solicitude decreases for those who die who are unknown to them, but concern for personal referents increases. Educators should be aware of the dramatic change of attitudes among students and the process of professionalization which might influence their caring of future patients.  相似文献   
37.
In a group of 43 smelter workers exposed to inorganic arsenic dust for 13-45 years, nerve conduction velocities (NCVs) were significantly lower in two peripheral nerves as compared with matching referents. With multivariate data analysis, a significant negative correlation was found between cumulative absorption of arsenic and NCV in four examined nerves and the sural amplitude. Clinical symptoms of neuropathy and other symptoms related to arsenic exposure were moderate, though the difference between the groups was significant. The mean total absorption of arsenic was calculated to be less than 5 g, and the maximal absorption about 20 g. These data indicate that the adverse effect of arsenic on the peripheral nerves is dependent on long-term exposure rather than on short-term fluctuations in exposure levels. © 1994 Wiley-Liss, Inc.  相似文献   
38.
无机汞对男工内分泌和大鼠睾丸微量元素的影响   总被引:1,自引:0,他引:1  
应用放射免疫分析法(RIA)和流行病学调查,对40名接触汞和40名非接触汞男工进行了血清甲状腺激素、性激素水平和生殖功能的测定。结果表明,接触组男工的阳萎、早泄、性欲减退发生率和男工妻子的早产、自然流产发生率以及血清甲状腺激素(FT3和FT4)含量明显增多,每周性交次数和血清睾酮含量显著减少。上述各项与对照组比较差异非常显著。应用火焰光度法,对氯化汞染毒后大鼠睾丸组织的微量元素进行测定,实验组的锌值明显降低。结果提示氯化汞能够影响甲状腺激素、睾酮和锌元素水平。  相似文献   
39.
崔玉中 《现代预防医学》2007,34(1):101-102,104
目的 为了解我市高中学生性心理发展及性教育状况。[方法] 对淄博市6所高中的高一学生进行了问卷调查,并对调查结果采用SPS统计软件进行卡方检验统计分析。[结果](1)男生和女生与异性交往的程度按所占比例高低依次为:一般朋友-约会-接吻;(2)有41%的男生表示爱上过异性,其中最小是在13岁;56%的女生表示爱上过异性,其中最小是在9岁,使爱上的异性成为自己恋人的男生有72%,女生占66.7%;(3)异性交往没有采取进一步行动的首要原因排在前5位的分别为:感情还没有到地步(17.1%),怕影响自己的前途(15.4%),我没有进一步欲望(8%),违背家庭的期望(7.95),不愿意勉强对方(6.85),[结论] 在高中阶段应加强性教育工作,指导学生与异性的正常交往.  相似文献   
40.
本文对正常人和某些内分泌疾病患者的拇指掌指关节内侧籽骨的出现情况进行了X线观察和分析,证实该籽骨的出现遵循一定时序,正常在青春发动期出现。在性早熟时该籽骨出现时间显著提前;而在垂体性侏儒症时则出现延迟,对某些内分泌疾病具有诊断价值。  相似文献   
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