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21.
Human ehrlichiosis is a recently recognized rickettsial disease. It is caused byEhrlichia chaffeensis, an intraleucocytic Gram-negative, obligate intracellular bacterium, grouped within the genusEhrlichiae. Most human cases of ehrlichiosis have been diagnosed in the USA. Two cases have been reported outside of the USA, one in Europe and one in Africa. From 1 January to 30 June 1992, 765 sera from blood donors or other asymptomatic subjects in 8 African countries, including Ivory Coast, Burkina Faso, Mali, Central African Republic, Angola, Zimbabwe, Mozambique and Commores Islands, were tested by indirect immunofluorescence for the presence ofE. chaffeensis antibodies. Positive sera were confirmed by Western immunoblotting. Only two of 765 sera tested were positive. One serum obtained from Burkina Faso had an IgG titer of 1:200 and one from Mozambique had an IgG titer of 1:80. Human ehrlichiosis seems to occur infrequently in Africa, although many more sera from additional African countries need to be evaluated.  相似文献   
22.
This article reports findings from a longitudinal survey of very elderly people living at home in London. The research aimed to identify social, psychological and physical characteristics associated with positive ageing and successful survival in the community in later life and its converse—negative ageing—as well as the associated policy implications. Associations with psychiatric morbidity, measured using the General Health Questionnaire, among sample members without cognitive impairment between the baseline interviews in 1987 and at follow-up, two and a half years later in 1990, are reported. Twenty-five per cent of survivors scored over the threshold of the GHQ in 1987 and 30% scored over the threshold in 1990. Half of those with a score over the threshold in 1990 also scored over the threshold in 1987. Hierarchical regression (using residualized change analysis) was used to estimate the effects of the independent variables on changes in psychiatric morbidity. The most significant predictor of psychiatric morbidity (GHQ score) in 1990 was baseline GHQ score, followed by health and functional status scores. Health and functional status were also the strongest predictors of baseline (1987) GHQ scores. The uniqueness of the study lies in the collection of follow-up data on a sample of very elderly people, given that most surveys are corss-sectional and contain too few people aged 85+ to merit separate analysis. It contributes to the small body of literature on outcome of depression. The lack of consistent associations with recovery from psychiatric morbidity in the literature enhances the importance of studies aiming to identify factors associated with different outcomes.  相似文献   
23.
F. Daschner  H. Rüden 《Der Chirurg》1997,68(9):941-944
Zusammenfassung. Viele Hygienema?nahmen in Operationsabteilungen sind durch wissenschaftliche Untersuchungen nicht belegt. Die in dieser Arbeit vom Nationalen Referenzzentrum für Krankenhaushygiene, das 1996 vom Bundesgesundheitsministerium eingerichtet wurde, zusammengestellten Empfehlungen stützen sich auf die Ergebnisse wissenschaftlicher Untersuchungen und trennen so die unbedingt notwendigen von den weniger bzw. nicht sinnvollen Ma?nahmen.
Summary. Many hygienic procedures performed in operation units are not supported by scientific investigations. The following recommendations by the National Reference Center for Hospital Epidemiology, founded by the German Ministry of Health in 1996, are based on the scientific literature and separate necessary from less necessary and unnecessary procedures.
  相似文献   
24.
本文从心血管病流行病学研究工作的实际体会中提出:当前要提高科研工作水平的关键是提高研究防治队伍的科学素质.其中包括:应具备流行病学和生物统计学的基本知识,必要的心血管病临床知识和实践经验,关心常见心血管病的基础研究进展,和学习有关专业的知识,如营养学、行为医学、遗传学等.解决的办法除集中培训,个人努力学习外,更需组织有不同专业基础而有志于心血管病流行病学研究工作的人员密切合作,相互学习,取长补短,以达到共同提高.  相似文献   
25.
本文对59名接触实验动物大白鼠引起23例流行性出血热(EHF)的流行病学和临床症状进行了调查,发病率为38.98%。发病的有副教授、讲师、助教、研究生等。发病多在春季,年龄组在21~40岁,男多于女。经间接免疫荧光技术检查,大白鼠肺EHFV抗原阳性率为32.69%。临床分型以中型为多,其次为重型和轻型。临床症状以发热、头痛、腰痛、全身痛、食欲不振、酒醉貌为主,没有死亡病例。血清间接免疫荧光抗体IgG在1:320~1:5 120之间的占91.30%。  相似文献   
26.
The epidemiology of urinary dysfunction in a Chinese population living in Hong Kong was investigated. Fifteen hundred ethnic Chinese women answered a telephone questionnaire including symptoms of urinary dysfunction, anthropometric measurements, obstetric history and place of birth. The relative predictive value of these factors was analyzed using logistic regression. The prevalence of urinary dysfunction was 13%. Ten percent reported stress incontinence, and 4% had urgency or urge incontinence. The strongest predictor was place of birth, with women born in mainland China having the highest prevalence of pure stress incontinence (OR 1.33, CI 1.1–1.6). For the symptoms of detrusor instability age was the strongest predictor, with women over 50 years being at greater risk (OR 2.8, CI 1.6–5.0). Contrary to earlier beliefs, urinary dysfunction in Chinese women is as common as in Caucasian women. Place of birth is the strongest predictor for pure stress incontinence, with women born in mainland China being at greater risk. This suggests that environmental factors in early life have a differential effect on the development of urinary incontinence. EDITORIAL COMMENT: Taiwan Chinese women have a comparable prevalence of urinary dysfunction with Hong Kong Chinese women. A survey representing a multistage sample of 82 678 women aged 18 years or older was conducted in the Taipei area from January to June 1993. A total of 818 cases were interviewed by trained students. One hundred and eighty-nine (23.1%) of the respondents reported having had some degree of incontinence in the preceding 12 months, 28 (3.4%) reporting regular incontinence. Most presented with stress urinary incontinence, whereas urge incontinence and mixed incontinence were more commonly seen in the elderly group (aged 60 years or older). The risk factors for urinary incontinence included age, number of vaginal deliveries (>3), number of abortions (>2) and maternal history of incontinence. Voiding symptoms (irritative or obstructive) and constipation were significantly more prevalent among respondents with incontinence than those without (P<0.001). This evidence also indicates that the long-held belief that Chinese women have a much lower prevalence of urinary dysfunction than western women has all but ended.  相似文献   
27.
Objective: To make an epidemiological analysis of the effect of environment on extremely severe road traffic crashes (RTCs). Methods: Epidemiologic data of extremely severe RTCs associated with environmental factors, including weather, topography, road conditions and other traffic conditions in Mainland China during 2000-2001, were collected and analyzed. Results: ( 1 ) During 2000-2001, there were 3 365 extremely severe RTCs with 13 666 deaths, 12 204 injuries and a direct economical loss of 136 million RMB. ( 2 ) Most extremely severe RTCs occurred in fine weather days and in the daytime. The high occurrence sites were plain areas, horizontal and straight roads, Grade B and C roads, ordinary road segment, and asphalt, smooth and mixed roads. (3) Compared with other RTCs, extremely severe RTCs were more likely to happen under following conditions: on cloudy, snowing, misty and blustering days; in hill and mountainous areas; on crooked and sloping roads; on freeway, Grade A, B, and C roads; mixed roads; ordinary, bridge, narrow and transitional roads; sand and dirt-roads; without traffic control measures; night without lighting. (4) Extremely severe RTCs of mountainous area or crooked and sloping roads were most severe in terms of deaths and injures per crash. Conclusions: Extremely severe RTCs are closely related with environmental factors. Rational road programming, enhancing road establishment and improving road conditions are probably effective measures to reduce the road traffic injuries.  相似文献   
28.
Data on the prevalence of antibody to hepatitis C virus among 278 subjects in an institution for the mentally handicapped were analysed by risk factors. A prevalence of 4% was found, higher than blood donors belonging to the same area (1.4%). No differences in prevalence with regard the length of residence, age, sex, degree of retardation or for presence of HBV markers were observed.  相似文献   
29.
本文报道100例原发全身性癫痫家系的遗传流行病学研究结果。先证者一级亲属患病率为6.86%,二级亲属为1.03%;分别是对照组一级亲属的13.83倍和2.08倍。原发全身性癫痫的遗传度为:一级亲属0.7521±0.0678,二级亲属0.3592±0.0746;加权平均0.5743±0.0502。说明遗传因素起重要作用。发病年龄影响因素分析表明:原发全身性癫痫有一定年龄依从性。EEG家系分析显示,该型癫痫一级亲属癫痫样放电明显高于对照组一级亲属,提示癫痫样放电的遗传倾向。  相似文献   
30.
Summary During an epidemiological survey on arc welders, serum copper and ceruloplasmin were determined in two groups of workers. One group consisted of aluminum welders who were divided into two groups: 13 welders working inside aluminum tanks (confined atmosphere) and 8 welders engaged in the production of vans for dump trucks (nonconfined atmosphere). The reference group consisted of 26 workers of the same plant who were not exposed to welding fumes. Ozone, the major pollutant in aluminum arc welding, was thought to be the principal factor in the significant decrease (P < 0.01) of mean ceruloplasmin in confined welders. This decrease in the level of ceruloplasmin was still within the reference values and was not linked to age or to tobacco consumption. We found a linear relationship between ceruloplasmin concentration and the cumulated worktime along the week. This effect could be a sign in the serum of a lung reaction against oxidant activity in this type occupational exposure.  相似文献   
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