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151.
Worksite health promotion programs have become increasinglyprevalent in the United States, and one or more health promotionprograms are found in two-thirds of all private worksites with50 or more employees. Reasons for recent growth in program frequencyinclude increased concern for worker health, rapidly escalatingemployer payments for health care benefits to workers, and growingevidence of a strong linkage between employee health and productivity.Published results of evaluations to date suggest that worksitehealth promotion programs can have positive impacts on healthbehaviors and health status. In addition, economic analysesare suggesting that some programs can affect the slope of healthcare costs and have the potential of high cost-effectivenesscompared to some clinical interventions. A number of researchchallenges remain, particularly understanding the influencesof the worksite environment and how employee health promotionprograms affect individual and organizational productivity.  相似文献   
152.
1275 patients were evaluated for HIV-1+2 seroprevalence and its association with clinical symptoms of HIV infection. Of 667 apparently healthy subjects, 8.2% had anti-HIV-1 antibodies. In 465 patients with clinical signs of AIDS, 39.4% were seropositive. 143 patients with miscellaneous symptoms had positive predictive values for HIV infection between 67% (vaginal ulcerations) and 20% (profound pyogenic abscesses). The WHO definition for AIDS had a specificity of 78.3%, a sensitivity of 72.2% and a predictive value of 61.6%.  相似文献   
153.
碰撞癌的临床影像学表现及病理分析   总被引:1,自引:0,他引:1  
目的:探讨碰撞癌的临床影像学表现、发病机制与病理特点。方法:回顾性分析20例碰撞癌的临床影像学资料并结合文献复习,总结其患病率、发病年龄、性别比、好发部位、临床影像学表现、治疗手段、病理特点。结果:碰撞癌罕见,好发年龄大于58岁,男性发病多见,好发部位为食管-贲门,食管-胃底等。临床表现无特殊,术前影像学检查多不能明确诊断,术后病理诊断是唯一的确诊方法。治疗以手术为主,辅以化疗或放疗。病理特点为同一宿主同一部位或器官2个不同类型肿瘤的结合,瘤组织间没有移行和混合,有各自的转移途径,碰撞癌以鳞癌和腺癌的碰撞为主。结论:碰撞癌是一种罕见的恶性肿瘤结合,临床特点有待进一步总结,影像学综合诊断有助于提高其确诊率。  相似文献   
154.
OBJECTIVES: Percentage of deliveries assisted by a skilled birth attendant (SBA) has become a proxy indicator for reducing maternal mortality in developing countries, but there is little data on SBA competence. Our objective was to evaluate the competence of health professionals who typically attend hospital and clinic-based births in Benin, Ecuador, Jamaica, and Rwanda. Methods: We measured competence against World Health Organization's (WHO) Integrated Management of Pregnancy and Childbirth guidelines. To evaluate knowledge, we used a 49-question multiple-choice test covering seven clinical areas. To evaluate skill, we had participants perform five different procedures on anatomical models. The 166 participants came from facilities at all levels of care in their respective countries. Results: On average, providers answered 55.8% of the knowledge questions correctly and performed 48.2% of the skills steps correctly. Scores differed somewhat by country, provider type, and subtopic. Conclusion: A wide gap exists between current evidence-based standards and current levels of provider competence.  相似文献   
155.
One prerequisite for standard clinical use of intravascular ultrasound imaging is rapid evaluation of the data. The main quantities to be extracted from the data are the size and the shape of the lumen. Until now, no accurate, robust and reproducible method to obtain the lumen boundaries from intravascular ultrasound images has been described. In this study, 21 different (semi-)automated binary-segmentation methods for determining the lumen are compared with manual segmentation to find an alternative for the laborious and subjective procedure of manual editing. After a preprocessing step in which the catheter area is filled with lumen-like grey values, all approaches consist of two steps: (i) smoothing the images with different filtering methods and (ii) extracting the lumen by an object definition method. The combination of different filtering methods and object definition methods results in a total of 21 methods and 80 experiments. The results are compared with a reference image, obtained from manual editing, by use of four different quality parameters—two based on squared distances and two based on Mahalanobis distances. The evaluation has been carried out on 15 images, of which seven are obtained before balloon dilation and eight after balloon dilation. While for the post-dilation images no definite conclusions can be drawn, an automated contour model applied to images smoothed with a large kernel appears to be a good alternative to manual contouring. For pre-dilation images a fully automated active contour model, initialized by thresholding, preceded by filtering with a small-scale median filter is the best alternative for manual delineation. The results of this method are even better than manual segmentation, i.e. they are consistently closer to the reference image than the average distance of all individual manual segmentations.  相似文献   
156.
活动性结核标志物'H-多肽的实验与临床研究   总被引:2,自引:0,他引:2  
本题研究是经免疫学途径直接检测人体感染结核菌的情况,为现代结核病的实验诊断、临床监测、流行病调查提供了一个全新的检验指标。作者首先发现了一种仅存在于活动性结核病患者体液中的蛋白成份—活动性结核标志物(ActiveTuberculosisMark—ATM)1H—多肽;并为之创立了独特的检测方法,经四年多临床19460例样本调查中确定了ATM的临床价值。将ATM检测与OT皮试、酶联免疫ELISA、DNA探针、PCR基因扩增技术及典型病例组患者行X线计算机断层摄影(CT)、磁共振像(MRI)等多组对比试验中,实验与临床研究资料分析证明:ATM检测的总敏感度为86.06%、特异度96.24%、准确度93.45%、诊断效率为82.82%、批内CV1.2%、批间CV2.0%、P<0.05。经NMR光谱分析结构含有CCH2官能团。  相似文献   
157.
There are many occupational stress management programmes availablewhich are designed to prevent and cure the negative aspectsof job-stress. The focus of the programmes can be directed towardsthe individual worker, the working group, the organization ofthe work or the organization as a whole. Moreover, programmesshow a considerable variation with respect to the type of interventionsthey promote and their underlying assumptions, as well as theirduration and costs. In this paper, effect studies of occupationalstress programmes published between 1987 and 1994 are reviewed.The aim is to give a practical overview of the variety in occupationalstress programmes, their scope, applicability and the evidenceof their effectiveness. The paper updates the review by DeFrankand Cooper published in 1989.  相似文献   
158.
浅谈临床教师的角色素养及道德要求   总被引:1,自引:0,他引:1  
探讨了临床教师的角色特征;认为临床教师的角色要求与现实状况之间存在反差;据此就其原因进行了分析。提出要强化临床教师的角色意识;在教学实践中自觉加强对其角色素养的自我锻炼和培养。  相似文献   
159.
Obstructive sleep apnoea is a relatively common sleep disorder that is popularly associated with snoring and excessive daytime sleepiness. It is a disorder with serious implications that has only in the last two decades received the attention of clinical specialists. The aim of this article is to review the role of the dental profession in the recognition and management of this disorder.  相似文献   
160.
Examination is a cornerstone in the manual procedures leading to mobilisation/manipulation of the low back. The observer variation of the more specific segmental tests remains to be investigated. Two skilled specialists in manual medicine examined the segmental changes in the lumbar spine. The patients were unknown to the examiners and no information of the case history was given. All test results were recorded by an observer present in the room who ensured that no conversation was allowed during the examination. The primary outcome measures were the kappa values for each test. The matching was defined as acceptable (acc) within two neighbouring levels and perfect (per) on the same level. Intra-observer variation (tested in 33 patients and 10 subjects without low-back pain): The agreement between first and second segmental diagnosis examination was 70% (per) and 82% (per + acc). Kappa values were: segmental diagnosis 0.60 (per) and 0.70 (per + acc), multifidus test 0.51 (per) and 0.60 (per + acc), sideflexion 0.57 (per) and 0.69 (per + acc), and ventral flexion 0.31 (per) and 0.45 (per + acc). Inter-observer variation (tested in 60 patients): The agreement for segmental diagnosis between the examiner A and B was 42% (per) and 75% (per + acc). Kappa values were: segmental diagnosis 0.21 (per) and 0.57 (acc), multifidus test 0.12 (per) and 0.48 (acc), sideflexion 0.22 (per) and 0.45 (acc), and ventralflexion 0.22 (per) and 0.44 (acc). By manual tests, skilled examiners seem to be able to diagnose segmental dysfunctions in the low back. The clinical implication of these dysfunctions remains to be clarified.  相似文献   
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