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151.
OBJECTIVES: To assess the effect of a medically induced abortion (MA) on birth weight in the first subsequent pregnancy. METHODS: Pregnant women who had had a MA, a surgical abortion (SA), or primigravidas with no history of abortion (NA), were recruited for a prospective cohort study between July 1998 and February 2001. The sample for the present analysis included 12995 singleton live births at term. RESULTS: The overall incidence rate of low birth weight (LBW) was 1.0%. The rates of LBW in the MA, SA, and NA groups were 1.0%, 0.9%, and 1.2, respectively. There were no significant differences in LBW rates between the MA and SA groups, neither between the MA and NA. Logistic regression analysis was used to estimate the effects of MA on birth weight, and we found no relationship between risk of LBW and MA. CONCLUSIONS: We did not find a statistically significant relationship between a history of one medically induced abortion and LBW for the first subsequent term pregnancy.  相似文献   
152.
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   
153.
采用配对病例对照研究,探讨先心病与柯萨奇病毒B3、B4感染的关系,结果显示:病例组与对照组患儿CVB3、CVB4.IgG抗体阳性率分别为59.3%、54.3%和53.6%、45.7%,差异天显著性(P值均>0.05);经单因素和多因素回归分析均未发现CVB3、CVB4感染与先心病有病因学联系(P>0.05)  相似文献   
154.
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   
155.
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   
156.
新兵基础训练期间过劳性损伤的前瞻性研究   总被引:11,自引:0,他引:11  
王波  陶惠人 《医学争鸣》1998,19(2):186-188
目的:查明我军基础训练中过劳性损伤的发病情况及分布特征。  相似文献   
157.
克隆特含漱液毒性实验研究   总被引:1,自引:1,他引:0  
目的探讨克隆特会激液对实验动物的毒性反应。方法小鼠灌胃给药、大鼠局部给药,连续观察14d内动物的毒性反应;将克隆特含激浪涂数干实验动物的完整和破损皮肤上,观察局部刺激作用、皮肤过敏反应;将克隆特含激法0.1ml缓慢注入明道内,每日一次,连续1wk,观察用道粘膜组织有无充血、水肿现象。结果克隆特合漱液小鼠灌胃30ml·kg-1体重(含甲硝吐150mg)无毒性反应;局部用药量为5ml·kg-1体重(合甲硝唑25mg)亦未出现毒性反应;对皮肤及明道粘膜无明显刺激作用,亦未见皮肤过敏反应。结论克隆特合漱法局部用药较安全。  相似文献   
158.
按随机抽样原则选择湖北恩施土家族人598名观测了眼的表面形态。该民族大部分人两眼位置适中,虹膜褐色,眼裂水平,开度中等,无蒙古褶,双睑;多为细窄眼型或中等眼型;眼的各径男大于女,一般存在性别差异;随年龄增加,眼型由中等型向细窄型转化,根据眼外形特征和聚类分析推测,土家人眼属于南、北方民族间的过渡型。  相似文献   
159.
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   
160.
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   
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