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101.
YB Cheung 《Public health》1998,112(2):113-117
In view of the rising divorce rates, the impact of divorce on health has an increasing importance in public health. The differentials in health between the married and the divorced may be explained by ‘marital selection’ and ‘marital protection’. Using longitudinal data from a study of the 1958 British birth cohort, factors that select people into divorce were identified from the areas of socio-economic status, health, and attractiveness, which included physical attractiveness, health-related behaviour and temperament. Evidence for both positive and adverse selection is found. The different sets of selection factors for females and males appear to be in line with gender role expectations. The health differentials between married and divorced men were weak and can be explained away by the selection factors. Having controlled for the selection effects, there were still significant associations between divorce and physical and psychological health in women. Though these unexplained differentials cannot be definitely interpreted as the consequences of marital dissolution, this interpretation remains plausible.  相似文献   
102.
The effects of calcium (Ca) on a hyperkalemic cardioplegic solution for continuous cardioplegia were examined in an isolated perfused working rat heart model. The coronary arteries were perfused with a modified Krebs-Henseleit bicarbonate buffer (K-H) solution, containing various concentrations of Ca(0.1, 0.6, 1.2, and 2.5 mmol/l) and a high concentration of potassium (20 mmol/l), for 180 min, after which cardiac arrest was induced at 37°C for 180 min. Cardiac function and creatine kinase (CK) were measured. In the control group, K-H solution was infused in place of the cardioplegic solution, and cardiac arrest was not induced. No significant differences were observed between the groups infused with the K-H solution containing Ca concentrations of 0.6, 1.2, and 2.5 mmol/l in the percent recovery of aortic flow (82.1±2.9%, 80.6±2.0%, and 71.5±3.7% (mean±SEM) respectively) or in the recovery of other indices of cardiac function, or in CK leakage. There were also no significant differences in the recovery of cardiac function and CK leakage between these groups and the control group. In the Ca 0.1 mmol/l group, however, the characteristic Ca paradox was observed. These findings suggest that if the Ca concentration in a cardioplegic solution is higher than 0.6 mmol/l during continuous cardioplegia, excellent cardioprotective effects will be achieved.  相似文献   
103.
朱玉琴  金花  于德华 《中国全科医学》2023,26(13):1598-1604
背景 近年来,国内针对多病共存患者在分级诊疗背景下就医机构选择行为的研究较少,研究多病共存患者的就医机构选择行为有重要的现实意义。目的 以分级诊疗为视角,分析多病共存患者就医机构选择行为及其影响因素,为进一步落实分级诊疗制度和合理配置医疗资源提供研究参考。方法 采用随机抽样法,选取2019-06-01至2020-01-01在上海市杨浦区中心医院医疗联合体(上海市杨浦区中心医院和上海市杨浦区定海、延吉、长白社区卫生服务中心)就诊的多病共存患者为研究对象。采用自设问卷对其进行调查,收集多病共存患者的一般资料,了解其对分级诊疗政策的认知情况及实际遵守情况、在不同疾病控制状况下至社区卫生服务中心首诊的意愿,以及其选择就诊医疗机构时考虑的因素等。采用二分类Logistic回归分析多病共存患者此次因病就医是否选择至社区卫生服务中心首诊的影响因素。结果 共发放1 100份问卷,回收有效问卷1 072份,有效问卷回收率为97.45%。1 072例多病共存患者中,老年(≥60岁)多病共存患者占85.07%(912/1 072)。624例(58.21%)患者表示知晓分级诊疗制度;940例(87.69%)患...  相似文献   
104.
Although tumour vasculature constitutes a biological factor playing a crucial role in the radiation response of tumours, the current procedures of assessment are semiquantitative, typically employing visual examination of stained histological material. Such techniques are also time consuming, and inefficient of extracting essential information on the vascular network. Image analysis has yet to contribute significantly in this direction, and most studies to date focus on blood vessel segmentation through empirical, user-selected thresholds. The present paper proposes an alternative segmentation approach, based on a probabilistic relaxation algorithm, applied in microscopic images of stained tissues. After image partitioning various information is obtained, such as vascular domains and geometrical characteristics of vessels.  相似文献   
105.
Effects of chemical mediators of anaphylaxis on ciliary function   总被引:2,自引:0,他引:2  
We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E1 (10(-8) M to 10(-6) M), prostaglandin E2 (10(-10) M to 10(-6) M), and leukotriene-C4 (10(-8) M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10(-5) M (7% increase in CBF), whereas prostaglandin F2 alpha (10(-10) M and 10(-6) M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function.  相似文献   
106.
The origins of the projections of the superior colliculus to the dorsal lateral geniculate nucleus and to the pulvinar in Dutch-belted rabbits were investigated using horseradish peroxidase (HRP) methods. Following injections of HRP in the dorsal lateral geniculate nucleus, retrogradely labeled neurons were found in the upper two-thirds of the stratum griseum superficiale of the ipsilateral superior colliculus. Most of the labeled somata were spindle-shaped, and their major axes tended to be perpendicular to the surface of the superior colliculus. In contrast, following injections of the pulvinar, labeled neurons were found in the lower third of the ipsilateral stratum griseum superficiale. In these cases, the labeled somata were larger than those labeled following dorsal lateral geniculate injections and were multipolar in shape.  相似文献   
107.
活性氧自由基在生物体内参与生理,病理过程并起重大作用,在筛选和评价抗氧化药物时,越来越需要一种快速,简便,价廉而又可靠的抗氧化活性测定方法,本文发展了一种具备了上述优点新方法,SOD(超氧化物歧化酶)及其模拟物的工作已有很多,很多文献报道了其活性一;Cu(Ⅱ)。本文着重研究了另一个金属辅基,Zn^2+并且发现了Zn^2+独特的,但为人们忽视了的;抗氧化活性加强作用。  相似文献   
108.
109.
The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups.  相似文献   
110.
Despite the growing interest in adopting information technology (IT) in healthcare, the degree of technology sophistication varies among healthcare organizations. Changes in the health care sector and continuous pressure to improve the quality of care have driven the evolution of IT in hospitals. This paper provides an overview of clinical IT sophistication in a sample of U.S. hospitals, and compares clinical IT capacities in this sample with a sample of Canadian hospitals. The instrument used for the comparison measures three clinical dimensions of IT sophistication: functional sophistication, technological sophistication and integration level. Clinical areas that were considered include patient management, patient care activities and clinical support activities. The comparison between hospitals in Iowa and Canada shows differences in clinical IT sophistication between the two settings. Hospitals in Iowa appear to have more technologies but fewer computerized processes and integration of patient management activities. Technological sophistication however, was low in both samples. Our findings confirm the construct validity of the measurement instrument and show initial evidence of its generalizability. More initiatives using the instrument would lead to enhancement in IT assessment tools that can be used for evaluation of IT in relation to patient management and quality outcomes.  相似文献   
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