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41.
The impact of occupational stressful life events on psychological distress and blood pressure was examined among employees of a major New York City brokerage firm undergoing massive layoffs. One hundred thirty-nine employees of the firm, who had participated in a blood pressure screening in 1986, were rescreened during the period of layoffs within their company in 1989. About two-thirds of the 139 employees reported being "somewhat" or "very" anxious or upset in 1989 during the period of layoffs, and psychological distress was significantly elevated among those employees reporting possible or definite layoff or job change and/or difficulty in obtaining a comparable job. However, we found no increase in overall blood pressure level, and no effect of anticipation of job loss on 1989 blood pressure when controlling for 1986 blood pressure level, age, body mass index, work hours, and other demographic variables. On the other hand, employment in a department sold to another employer on the day of screening, as well as employment in a clerical job title, were both associated with significant increases in diastolic blood pressure of about 5 mm Hg.  相似文献   
42.
(1) The objective of the study was to compare physiologicalwork during exercise using treadmill, bicycle, and arm-assistedstep tests. (2) Twelve probands were stressed in randomized order on thethree devices at workloads of 50, 100, 150, and 200 W. O2 uptake,heart rate, respiratory minute volume, and additional derivedparameters were measured. (3) Values obtained with the bicycle and arm-assisted step testaccorded at all workloads; a linear relationship was observedbetween workload in watts and O2 uptake. For the treadmill,accuracy depended on the formula used for calculation of energycost. At the 200 W level, the horizontally positioned treadmillrequired considerably more physiological work than calculated. (4) It is concluded that comparison of different forms of exercisehas to be done with caution particularly if the higher speedsof the treadmill (‘running’) are used. (5) For practical ergometry, especially for exercise testingin elderly patients with suspected coronary heart disease, thearm-assisted step test is considered to be advantageous. Thisform of exercise can be applied even to people with handicappedlegs; it avoids premature fatigue by involving a large musclemass. It shows equal accuracy as compared to the more complicatedforms of exercise.  相似文献   
43.
Summary Ten iron foundry workers representing typical foundry occupations were examined. The amount of lung contamination was estimated after the workers' thoracic area had been magnetized and the remanent magnetic field measured. Chest radiographs were classified according to the siderotic, silicotic, and nonspecific changes found; and the changes were then divided into four categories.The preliminary results of the electron micrographs indicated that the size and shape of the pollutants varied greatly according to the type of foundry site. In addition, the estimated amount of lung contaminants in the subjects varied between 30 and 600 mg. A good correlation (r=0.86) was obtained between radiological siderotic and silicotic changes, and the correlation between both of these radiological findings and the measured average permanent magnetic field was rather good (r=0.60). There was no correlation between the estimated exposure (neither length nor magnitude) and the amount of retained lung contaminants, and therefore a balance between retention and clearance seemed to have been achieved. These results indicate that the magnetic measuring method can be used to evaluate the amount of lung contaminants retained by foundry workers.  相似文献   
44.
A structured interview was used to examine the 1-year incidence and prevalence of depression among 116 first-year university students. While 24 of the subjects (20.7%) met the Diagnostic and Statistical Manual of Mental Disorders 4th ed. (DSM-IV) criteria for Major Depressive Episode (MDE), 62 (53.4%) met the Diagnostic and Statistical Manual of Mental Disorders 3rd ed. Revised (DSM-III-R) criteria for MDE, and 27 (23.3%) also met the Research Diagnostic Criteria (RDC) for Major Depressive Disorder (MDD) for the 12 months prior to the interview. Moreover, 23 of the subjects (19.8%) had onset of the DSM-IV criteria for MDE, 54 (46.6%) had onset of the DSM-III-R criteria for MDE, 24 (20.7%) had onset of the RDC for MDD, during the same time period. These high rates of depression may be explained by the students' difficulties in and by their readjustment after entering university.  相似文献   
45.
The disparity in resources between economically developed and developing countries presents ethical concerns when commercial sponsors of studies and investigators propose to conduct them with subjects in developing countries. Vulnerable people may be recruited into studies of little health benefit to themselves or their communities and, under undue inducements, may accept disproportionate risks. Reproductive health studies may present women with undue risks. Guidelines have been developed to protect exploitable populations in resource-poor settings, although guarding their right to make informed and voluntary choices poses special challenges. Guidelines pay special attention to pregnant women as research subjects, and may approve and even require their enrollment in studies of products not known to be harmful. Placebo-controlled studies are addressed in contexts where no recognized treatments are routinely accessible. The structure and functions of research ethics review committees present difficult challenges, but they may be mitigated by enlightened international collaboration.  相似文献   
46.
BACKGROUND: In tracheally intubated or tracheostomized spontaneously breathing patients, tube resistance can highly increase the patient's work of breathing. In this study we focused upon the relationship between total (WOBtot) and tube-related additional inspiratory work of breathing (WOBadd) and compared different ventilatory modalities for proper tube compensation. METHODS: In ten tracheostomized spontaneously breathing patients we measured WOBtot and WOBadd in the continuous positive airway pressure (CPAP) mode, under inspiratory pressure support of 5, 10, and 15 cmH2O in the pressure support ventilation (PSV) mode, and under flow-adjusted pressure support in the automatic tube compensation (ATC) mode. WOBadd and WOBtot were calculated on the basis of measured tracheal pressure and esophageal pressure, respectively. Inspiratory peak tracheal pressure above PEEP was taken as an estimate of pressure support beyond mere tube compensation (i.e., overcompensation). RESULTS: The percentage of the tube-related WOBadd on WOBtot in the CPAP mode was 52%. It decreased with increasing pressure support in the PSV mode from 32% (PSV 5 cmH2O) to 17% (PSV 15 cmH2O). WOBadd was only 15% of WOBtot in the ATC mode. In contrast to the other ventilatory modes, reduction of WOBadd in the ATC mode was achieved with the smallest amount of overcompensation, i.e. with minimal pressure assist beyond mere tube compensation. CONCLUSION: In tracheally intubated or tracheostomized spontaneously breathing patients, adequate compensation of tube resistance (i.e. with minimal overcompensation and minimal undercompensation) is best done by the ATC mode.  相似文献   
47.
刘步平 《中医教育》2004,23(1):33-35
思想政治工作是我国高等教育的生命线,如何提高思想政治工作的质效是每一位教育工作者不能不关注的重大课题.实践证明,以"三个代表"为指引,以民主管理为重点,确立学生的中心地位,树精品战略,提高学生文化素养、科技创新等能力,能够很好地提高学生思想政治工作的质效,培养出适应时代需要的高级中医人才.  相似文献   
48.
目的:通过对近十年不同灸法治疗原发性痛经的临床研究文献进行整理分析,了解各种灸法治疗原发性痛经的临床疗效,以期择优选择适宜灸法治疗原发性痛经。方法:以"灸""原发性痛经""功能性痛经"为主题词,在中英文数据库上检索近十年(2010年1月—2020年2月)灸法治疗原发性痛经临床研究文献。结果:临床上灸法治疗原发性痛经的方法众多,主要以温和灸、温针灸、热敏灸为主,应用灸法治疗原发性痛经最多的证型是寒凝血瘀型(或寒湿凝滞型),但大部分临床研究未进行辨证给予艾灸治疗痛经以及同种证型痛经应用不同灸法的疗效差异未进行比较。结论:各种灸法治疗原发性痛经的临床疗效均较显著,但疗效差异不详,故今后要开展更多高质量的临床研究不同灸法治疗痛经之间疗效差异,明确不同证型痛经所适宜的灸法以提高临床疗效。  相似文献   
49.
随着人们对电离辐射对人类健康危害的认识,以及随之开展的电离辐射生物效应及防护措施的研究,逐步形成了放射卫生学。因此作为传统的公共卫生体系下的五大卫生之一,放射卫生主要围绕电离辐射对人体健康有害影响及其综合防护措施开展工作。从上世纪三、四十年代起,经过近百年的蓬勃发展,现阶段我国的放射卫生学学科水平和放射卫生工作成效等有了很大提升。本文就放射卫生学研究与我国放射卫生工作的历史、现状、工作内容等情况进行简单的概述,以期为我国放射卫生工作今后的发展提供助力。  相似文献   
50.
目的:测定市场上实际流通的商品胡桐泪药材中多糖的含量并对其单糖组成进行分析,以多糖为指标评价药材质量。方法:采用苯酚-硫酸法对总多糖进行含量测定;应用核磁共振氢谱(1H-NMR)分析单糖组成;运用高效凝胶渗透色谱(HPGPC)测定总多糖的分子量分布。结果:以葡萄糖计,4批新式胡桐泪总多糖含量平均值为(7.36±1.74)%,6批老式胡桐泪总多糖含量平均值为(1.53±0.99)%;新式与老式胡桐泪总多糖的单糖组成相似,主要由阿拉伯糖和半乳糖组成,还含有木糖、甘露糖、鼠李糖等,部分样品尚含有较高含量的葡萄糖;新旧类型样品总多糖在分子量分布上存在较大差异。结论:新式胡桐泪的总多糖含量平均值较老式高,以多糖含量为评价指标时,新式样品总体质量较老式更好;应用核磁共振氢谱可以快速、准确地鉴定单糖组成。  相似文献   
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