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91.
原发性闭角型青光眼发病危险因素的病例对照研究 总被引:5,自引:0,他引:5
为探讨原发性闭角型青光眼的发病危险因素,对103例原发性闭角型青光眼患者和95例非青光眼对照者进行了回顾性病例对照研究。结果发现原发性闭角型青光眼的主要危险因素有青光眼家族史、脾气暴躁及易激动、近距离用眼职业和高血压病,未发现吸烟、饮酒、糖尿病、近视眼和ABO血型与原发性闭角型青光眼的发病有统计学联系。 相似文献
92.
同济医科大学控烟活动及效果评价 总被引:1,自引:0,他引:1
我校自1993年开展控烟工作,1995年9月开始创办无吸烟大学校园,采取了卫生宣教和行政干预等综合措施,并进行了效果评价。高强度干预措施实施前期(1995年3月)和中期(1996年10月)相比,男医学生和男女学生平均吸烟率分别从16.3%和11.4%下降到9.6%和5.94%;男教工和男女教工平均吸烟率分别从28.6%和13.8%下降到13.9%和8.86%。 相似文献
93.
Guidotti T. L.; Watson L.; Wheeler M.; Jhangri G. S. 《Occupational medicine (Oxford, England)》1996,46(4):265-274
This is the first round in a series of surveys conducted inFort McMurray as part of the Fort McMurray Demonstration Projectin social marketing. This component of the survey was intendedto focus on the most prominent group of employed workers inthe community and to compare their patterns of response withthe community as a whole. Respondents to the survey were overwhelminglymale (96%), married (72.9%) and living in households of twoto five persons (87.9%). They were predominantly aged 30–44(55%) and graduates of high school (53.5%). Younger male workers(below age 30) were more likely to have a high school diploma(78.3%) or some additional technical or vocational training(21.7% compared to 12.5% overall) and to be unmarried or separated.Attitudes toward safety-related behaviours were stronger thanfor respondents from the community as a whole. Approximately70–100% of all age groups and both sexes showed strongagreement with attitudes involving child car seats and the unacceptabilityof drinking and driving. These attitudes include strong advocacyof vigorous enforcement of occupational health and safety standards.However, they showed a variability similar to the communityas a whole in behaviour at home compared to work, generallyreporting more consistent use of personal protection on thejob than in their own homes, particularly hearing protection.Even so, they were much less likely to perform stretching andwarm-up exercises prior to exertion than community residentsin general. The potential may exist to transfer the technologyand attitudes from workplace health and safety to communitysafety. One possible strategy to accomplish this is to involveworkers in this industry directly in community initiatives.This strategy may be generalizable to any community in whichthere are major employers who place a heavy emphasis on riskcontrol and occupational health and safety. 相似文献
94.
Respiratory symptoms and lung function following exposure in workers exposed to soft paper tissue dust 总被引:3,自引:0,他引:3
Jens Ericsson Bengt Järvholm Fredrik Norin 《International archives of occupational and environmental health》1988,60(5):341-345
Summary The objective of this study was to investigate if the dust in a mill producing soft paper tissue caused respiratory symptoms or impaired respiratory function. Using a questionnaire and spirometry, 355 persons were examined. They were divided into three groups according to present exposure to dust; low (< 1 mg/m3), moderate (1–5 mg/m3) and heavy (> 5 mg/m3). There was a dose-dependent increase of symptoms from the upper respiratory tract. However, coughing and coughing with phlegm were not found to be more common among persons with heavy exposure compared to those with low exposure to the dust. There was no difference in FEV, or FVC during a work shift. Persons with long-term (> 10 years) and heavy exposure to dust seemed to have impaired respiratory function compared to those with low and/or short-term exposure to the dust. 相似文献
95.
Analysis is presented of the relationship between decline in ventilatory function and possible symptoms of bronchial hypereactivity. Data comes from three consecutive surveys within a 13-year follow-up study of a population sample of 1747 persons (718 males and 1029 females) who completed spirometric testing and interviews. Chest symptoms recorded in the two initial surveys were used as baselines for the prognostic study on FEV1 change. To evaluate changes in lung function the FEV1 decline index, expressed as percentage of FEV1 loss during the study period, was calculated. Chronic wheezing and asthma-like attacks were very strongly related to FEV1 baseline level. Multiple linear regression analysis for each separate symptom including age and smoking habits as confounders and showed that the FEV1 decline index was higher and more significant when wheezing and asthma-like attacks or chronic cough were present. When the combination of symptoms were introduced into the regression model, the effect of wheezing became insignificant. Only attacks of shortness of breath in both sexes and chronic cough in women were significantly associated with more rapid FEV1 decline. However, the effect of persistent wheezing in men had a rather substantial impact on FEV1 change. Comparing the effect of the number of cigarettes smoked with the effect of symptoms, one can see that FEV1 decline due to attacks of shortness of breath is comparable to that seen with heavy smoking. There was no strong evidence that the symptoms under study precede the more rapid FEV1 decline. 相似文献
96.
M. K. Watson L. S. Jakobson 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,117(2):273-280
In the present study, a kinematic analysis was made of unconstrained, natural prehension movements directed toward an object
approaching the observer on a conveyor belt at one of three constant velocities, from one of three different directions (head-on
or along the fronto-parallel plane coming either from the subject′s left or right). Subjects were required to grasp the object
when it reached a target located 20 cm directly in front of the hand′s start position. The kinematic analysis revealed that
both the transport and grasp components of the movement changed in response to the experimental manipulations, but did so
in a manner that guaranteed that, for objects approaching from a given direction, hand closure would begin at a constant time
prior to object contact (regardless of the object’s approach speed). The kinematic analysis also revealed, however, that the
onset of hand closure began earlier with objects approaching from the right than from other directions – an effect which would
not be predicted if time to contact was the key variable controlling the onset of hand closure. These results, then, lend
only partial support to the theory that temporal coordination between the transport and grasp components of prehension is
ensured through their common dependence on time to contact information.
Received: 20 September 1996 / Accepted: 16 June 1997 相似文献
97.
98.
N. Crowcroft H. Maguire M. Fleming J. Peacock J. Thomas 《The Journal of hospital infection》1996,34(4):301-309
A retrospective case-control study of 50 MRSA-positive patients was carried out during an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) at an acute general hospital in London. Controls were randomly selected from MRSA-negative patients admitted during the outbreak period. Risk factors investigated included length of admission prior to screening, number of ward changes, main diagnosis, extent of staff contact, pressure sores, surgical and other invasive procedures and antibiotic treatment. Outcome variables examined were rates of infection (versus colonization) with MRSA and mortality. Patients with MRSA were in hospital longer before microbiological specimens were taken and moved wards more often than controls. In a logistic regression analysis, length of stay in hospital, pressure sores, physiotherapy and surgical procedures were associated with a significantly increased risk of acquiring MRSA. Odds ratios (and 95% confidence intervals) for having acquired MRSA were: 8·3 (1·02−71·43) if a patient had pressure sores; 3·7 (1·10−12·5) if they received physiotherapy; and 3·2 (1·82−10·0) if they underwent surgical procedures. The rate of clinical infection amongst patients with this strain of MRSA was 26% and included life-threatening infections such as septicaemia, underlining the potential virulence of MRSA. Surgery and physiotherapy may have been markers of debility. Physiotherapy was probably a marker of increased rates of contact with all hospital staff, and high standards of hand hygiene should be promoted amongst all staff as the most important factor in controlling an outbreak of MRSA. Good bed management is essential for hospital infection control. 相似文献
99.
Lars Bendtsen Rigmor Jensen Jannick Brennum Lars Arendt-Nielsen Jes Olesen 《Cephalalgia : an international journal of headache》1993,13(3):184-191
The duration of the late exteroceptive suppression period (ES2 ) of temporal muscle EMG activity has been reported to be reduced in patients suffering from chronic tension-type headache. Methods of recording and analysing ES2 have varied between centers and reproducibility of results within subjects , although insufficiently studied, has generally been poor. ES2 was investigated in 30 healthy subjects, using a computerized technique of recording, rectifying and averaging the EMG signals. Hour to hour and week to week variations of ES2 durations were calculated, and the influence of pain during a cold pressor test and of sustained muscle contraction on ES2 durations was investigated. The intra-individual variation of ES2 durations was 16.0% from hour to hour and 20.7% from week to week. The inter-individual variation was 36.7%. The present method for analysis of ES2 periods proved to be reliable, as the intra-observer variation was 4.2% and the inter-observer variation 4.6%. ES2 periods were significantly shorter on the first compared to the second day of examination ( p = 0.006) and during experimental pain ( p = 0.0005). We recommend the use of the computerized averaging technique in future studies and caution against the dependence of results upon factors such as conditioning and pain. 相似文献
100.
Hans-Günter Neumann 《International archives of occupational and environmental health》1988,60(3):151-155
Summary Analysis of hemoglobin adducts in blood samples is suitable for the biological monitoring of genotoxic chemicals. The method is specific because the compound to which the individual was exposed is identified. The sensitivity of the method depends on the analytical procedure applied, but is hardly limiting since large amounts of the protein can be obtained. The method provides not only information about the internal exposure to the environmental chemical, but also about the individual's capacity to generate ultimate genotoxic metabolites from it. Since macromolecular damage in blood cells is correlated to that in potential target tissues, this information is relevant to risk assessment, insofar as macromolecular damage produced by a specific chemical can be correlated with the development of tumors. 相似文献