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11.
米非司酮作用于兔输卵管收缩活动与Ca^2+关系的研究   总被引:1,自引:0,他引:1  
通过“结合化学分离与原子吸收分光光度法”对Ca^2 含量测定和离体输卵管肌条收缩记录方法,研究米非司酮(Ru486)对增加假孕(4d)兔输卵管平滑肌收缩频率,而不改变其收缩张力和振幅时与Ca^2 之间的关系,结果提示:(1)Ru486对输卵管分泌液和组织内Ca^2 的含量分布无明显影响;(2)Ru486具有降低细胞外液高Ca^2 浓度促Ca^2 内流,而使收缩增强的效应,且能协同Ca^2 通道阻断剂(Verapamil)抑制细胞外Ca^2 内流,而致收缩减弱的效应。  相似文献   
12.
Zusammenfassung In der Onkologie gewinnen medizinisch-ökonomische Aspekte eine immer größere Bedeutung. In Anbetracht des Anstiegs der Gesundheitsausgaben und der immer teureren Interventionen müssen Wege aufgezeigt werden, wie mit den vorhandenen finanziellen Mitteln Prioritäten gesetzt werden können. Die medizinische Ökonomie, eine vergleichsweise junge Wissenschaft, beschäftigt sich unter anderem mit der ökonomischen Bewertung medizinischer Technologien mit dem Ziel der Verbesserung der gesundheitspolitischen Entscheidungsfindung. Dieser Artikel beleuchtet die Grundlagen dieser Wissenschaft, einschließlich der ökonomischen Evaluation, im Kontext der internistischen Onkologie. Zweifelsohne wird die medizinische Ökonomie in Zukunft in der ärztlichen Fort- und Weiterbildung eine ähnlich wichtige Rolle spielen wie klinische Epidemiologie und evidenzbasierte Medizin.  相似文献   
13.
质疑Frank—Starling心脏定律   总被引:4,自引:4,他引:0  
何川  何培芳 《西部医学》2009,21(10):1639-1646
心脏收缩释放的能量(作功)是心肌纤维长度(心室舒张末期容积,EDV)的函数,即Frank—Star一1ing(FS)心脏作功定律,被誉为心脏生理学中的“经典”理论。对此,笔者从各种不同角度进行了探讨:首先分析了Frank伸展离体心肌和Starling及其同事使用心肺制备做的实验与动物生理实际的差异,以及人们在实验中观测到的增加心肌前负荷引起收缩力增强的现象(FS现象),认为:①在正常生理条件下的动物体内,来自心脏以外的、如同心肺制备中那样人工控制心室充盈压力升高、引起EDV增加的那种血液的重力动力是不存在的。②另一方面,人为地增加前负荷,那是改变了心肌收缩时的外环境条件。③由此而激发出的FS现象,是心脏适应其外环境条件变化所作出的反应。④此种心肌收缩力增强的反应,需通过心肌细胞内部与收缩过程发生有关的心肌兴奋一收缩和化学一力学偶联等一系列生化机制(不恒定因素)方能得以实现。⑤根据他们实验中观测到的FS现象,在逻辑上不能得出前负荷这一心肌收缩时的外环境条件变化调控其作功的推论。换言之,所有的在实验中被激发出来的FS现象,都不足以成为支持FS心脏定律的证据。然后,引用国内外公认的计算心脏每搏射血作功(w)的生物物理学公式“w=P×(EDV—ESV)”,证明了w和EDV之间没有函数关系。根据心脏作功的医用物理学和生物数学的基本原理,笔者认为Frank—Starling心脏定律表达的不是心脏作功的规律。  相似文献   
14.
The effectiveness of interdisciplinary treatments for chronic pain is well established. In general, these treatments decrease psychosocial distress and increase physical abilities. Further, return to work rates following interdisciplinary treatment tend to be quite high. Previous studies have highlighted a number of factors that individually influence return to work rates; however, there is a need for more comprehensive and unified models that allow an evaluation of the inter-relations among these factors. The present investigation examined how demographic and treatment outcome variables interacted to influence post-treatment return to work rates in a sample of individuals with chronic pain following interdisciplinary treatment. Results indicated that patient age, lifting ability, pain duration, depression level, and reported disability were individually related to return to work; however, when these variables were evaluated relative to one another, level of depression and patient age had the best ability to predict post-treatment work status. These results add to the literature by specifically highlighting post-treatment factors that best discriminate patients who had returned to work from those that had not. Furthermore, they provide evidence that general emotional distress is perhaps the most important predictor of work status following treatment.  相似文献   
15.
Over the past 10 years, I have been privileged to conduct educational forums for audiences containing many recovering alcoholics or otherwise chemically dependent persons. In these forums about the addictive diseases and their treatment and research possibilities, significant interaction with the audience members occurs. During these interactions, certain anecdotal phenomena seem to predominate. The repetitive nature of these reports suggests the need for systematic investigation. As with editorial comments in major medical journals, observed phenomena and unanswered questions from those afflicted can be valuable in the generation of testable hypotheses. Perhaps the ideas presented herein will be useful in the development of future research on alcohol abuse and alcohol dependence.  相似文献   
16.
Rehabilitation is under-represented in the neurological literature on disabling diseases. A Medline search was conducted to retrieve the articles published between January 1991 and June 1994 under the main headings of Stroke, Parkinson's disease, Multiple sclerosis, Brain injury, Ataxia and Dementia. These were then combined with the sub-heading Rehabilitation. The former search yielded 27724 articles, the latter 1272 (4.6%). In 1992, the Journal of Citation Reports (JCR) assigned to Journals publishing rehabilitation papers an average Impact Factor (IF) of 0.7–2.8 (median 1.8): that is, 31–90% (depending on the various main headings, median 68%) of the average IF given to Journals publishing non-rehabilitation papers. In the present study, the weight of the literature was defined as the product of the number of articles multiplied by the IF of the corresponding Journal (IF=0 for non-JCR Journals). Across the various neurologic conditions, the weight of the Rehab literature was 0.1–7% (median 2%) of the weight of the non-Rehab literature. The results suggest that neurology is still reluctant to face the disability challenge.
Sommario La riabilitazione è scarsamente rappresentata nella letteratura neurologica sulle patologie che causano disabilità. Gli Autori hanno interrogato la banca-dati Medline nella ricerca degli articoli pubblicati fra il Gennaio 1991 ed il Giugno 1994 sotto le parole-chiave Stroke, Parkinson's disease, Multiple Sclerosis, Brain injury, Ataxia e Dementia. È stato poi eseguito un incrocio con la parola-chiave secondaria Riabilitazione.La prima ricerca ha prodotto 27724 articoli mentre la seconda ne ha prodotti 1272 (4.6%). Nel 1992 il Journal of Citation Reports (JCR) ha attribuito alle Riviste che hanno pubblicato articoli con tema riabilitativo un Impact Factor (IF) medio di 0.7–2.8 (mediana 1.8), pari al 31–90% (a seconda della parola-chiave principale: mediana delle percentuali 68%) dell'IF medio attribuito alle Riviste che hanno pubblicato soltanto articoli su temi non riabilitativi. In questo studio è stato definito come peso della letteratura il prodotto del numero di articoli per l'IF delle rispettive Riviste (IF=0 per le Riviste non censite dal JCR). A seconda delle diverse patologie neurologiche, il peso della letteratura riabilitativa variava fra 0.1 e 7% (mediana 2%) del peso della letteratura non riabilitativa.I risultati suggeriscono che la Neurologia sia ancora riluttante ad affrontare la sfida che le pone la disabilità.
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17.
18.
Exposure to mineral dust was studied among construction workers (N = 437) with the aid of a questionnaire and a chest X-ray examination of the lungs. The results of the questionnaire showed that 81% of the construction workers had been exposed to asbestos. Exposure had occurred in all of the occupational groups studied. Pleural plaques and/or lung fibrosis (ILO greater than or equal to 1/1) were found in 26% of the examined workers; the prevalence varied from 18 to 40% among the various occupational groups. Comparison with a representative sample of the Finnish male population from another investigation indicates that the frequency of lung fibrosis (ILO greater than or equal to 1/1) is at least two times higher among the examined construction workers than among the general population. It seems likely that exposure to asbestos dust can be considered an etiological factor for an appreciable number of the X-ray findings.  相似文献   
19.
A review of the international literature on staffing in childcare centres in five English language countries and Denmark reveals both remarkable similarities and interesting differences in the childcare workforce. The paper compares characteristics of the workforce; their training and professional membership. It also compares conditions of work in each country, including salaries, staff benefits, and features of the working environment such as job satisfaction and staff turnover. Findings indicate that childcare workers tend to be young and female; that a relatively high proportion of untrained staff work in childcare centres; that, except in Denmark, the level of extrinsic benefits is startlingly low. Workers are paid relatively little compared to the average pay for women in their countries but the workforce does not benefit from enhanced conditions of work to compensate for low pay. However, the level of intrinsic satisfaction with the work is high. Caring for children is a satisfying form of employment, even if it offers a limited career structure.  相似文献   
20.
为阐明课间加餐对中学生上午学习能力的影响,采用剂量作业试验,通过自身前后对比,分析了间餐与脑力工作能力的关系,结果表明间餐不仅加快了脑力工作速度,控制了末节课的错误率,而且较有效地降低了显著疲劳发生率,经logistic逐步回归分析,显示间餐及高质量早餐均为阻遏疲劳发生之保护因子。  相似文献   
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