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排序方式: 共有2404条查询结果,搜索用时 15 毫秒
991.
In a sample of 260 married men in Shiraz, the relationship of fertility to demographic, socioeconomic, and psychosocial (perceived economic value of children) variables is studied. The number of children ever born is closely associated with duration of marriage, but socioeconomic variables also exert a significant influence, especially the wife's educational level. Recent fertility is more closely associated with age of wife, but also with ownership of modern goods, which is also the major factor in current contraceptive use. The perceived value of children appears unimportant, negligible in recent fertility and contraceptive use and showing only a slight positive relationship between expected reliance on children for support in old age and the number of children ever born. 相似文献
992.
993.
In a three-year period a community hospital of 40 beds discharged 2086 patients, their mean length of stay being 14.8 days. Some 68% of the patients treated were over 65, and 8.9% died in hospital. While the most common diagnosis on admission was disease of the respiratory tract, this does not indicate the actual cause of admission. For 142 patients from one practice this was acute illness in 44% of the cases, assessment in 20%, and a need for nursing care in 36%. If the community hospital had not been available about half these patients would have been admitted to the general hospital. 相似文献
994.
995.
996.
Immunosuppressive agents are frequently used in transplant recipients for prevention of homograft rejection and in patients with leukemia for treatment of their primary disease. From 1973 to 1975, fifty-nine patients undergoing renal transplantation and forty-one patients with leukemia were treated at the University of California (Davis) Medical Center. Intestinal necrosis and perforation developed in four (7 per cent) of those receiving transplants and in four (10 per cent) of the patients with leukemia. One transplant receipient and all four patients with leukemia had extensive necrosis of both the small and large intestines. Two transplant recipients had isolated sigmoid perforations, and one had splenic flexure colonic perforation. All died from septicemia with septic shock. The etiology of these intestinal complication appears related to immunosuppressive agents, particularly high dosages of steroids. Despite the grave prognosis, early surgical intervention is the only method of dealing with these complications. Early diagnosis as well as properly timed and selected operations are necessary for the successful management of these patients. 相似文献
997.
998.
The cyclic 2,18-bridged biliverdin (2) is excreted in rat bile without reduction to the corresponding bilirubin. Conformational analysis, employing an optimized Monte Carlo method and a mixed Monte Carlo/stochastic dynamics, reveals that biliverdin IXalpha (1) and the cyclic analogue 2 adopt 'lock washer' conformations, stabilized by the presence of intramolecular hydrogen bonds between N23...H22N and, to a lesser extent, between N23...H24N. Although 2 is very similar in overall shape to 1, the former adopts a 'locked lock washer' conformation unable to undergo fluctuations, thus possibly hampering a proper recognition by biliverdin reductase. 相似文献
999.
1000.
Starr K. Sage Susan G. Gerberich Andrew D. Ryan Nancy M. Nachreiner Timothy R. Church Bruce H. Alexander Steven J. Mongin 《Accident; analysis and prevention》2010,42(1):1-9
To investigate the relation between schools’ resource levels (i.e., annual per student expenditures), school resource allocations, and physical assault (PA) against Minnesota's educators, a study was conducted from the two-phase Minnesota Educators’ Study (MES) that incorporated school-level fiscal and demographic data from the Minnesota Department of Education (MDE). The MES examined a randomly selected cohort of employed, state-licensed kindergarten through grade 12 educators. From mailed questionnaires, response rates for both Phase I (comprehensive data collection on violent events) and Phase II (case-control) were 84%. Cases experienced a work-related PA event in the previous 12 months; controls reported no assaults. Based on the school in which they worked the most time and available MDE school-level data, together with MES questionnaire data, analyses were conducted on 238 cases and 640 controls. Multivariate analyses, using directed acyclic graphs to guide selection of confounders, suggested that increased spending (i.e. resources) was associated with decreased risk of PA. Analyses further suggested that the highest quartiles of resource allocations, compared with the lowest quartiles (referents), were associated with decreased risks of PA for: district level administration; regular instruction; special education; student activities and athletics; and pupil support services expenditures. Associations between increased resource allocations to student activities expenditures and decreased risks of PA were the strongest. For example, an allocation greater than 5% of the total annual per student expenditure to student activities programming (referent, less than 0.04%) was associated with a decreased risk of PA (OR = 0.30, 95% CI: 0.12, 0.77). Results suggested that allocations of school resources (i.e., expenditures) to key program areas such as student athletics and extracurricular activities may reduce risk of work-related PA against educators. Research to further explore the nature of the relations between disparities in school resources and spending, resource allocations, and PA will be important to the continued development of relevant prevention strategies. 相似文献