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21.
Sixty-six patients requiring catheterization in the course of general surgical operations were randomly allocated into two groups. Of the 34 patients catheterized urethrally 16 developed urinary tract infections whereas of the 32 suprapubically catheterized patients only 2 developed an infection (P less than 0.001). Five patients required recatheterization after removal of their urethral catheters. There were no major complications associated with the use of suprapubic catheters. We propose that, when catheterization is required during a general surgical procedure, the suprapubic route is to be preferred.  相似文献   
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Changes in the health care needs of American children over the past two centuries have engendered school health programs. Issues related to the role and responsibilities of school nurses within these programs have existed from the beginning. Current societal pressure for schools to assume even greater responsibility for providing health care has necessitated a precise definition of these roles and responsibilities. The purpose of this article is to review existing literature related to school nursing in this country and to describe the results of a study documenting state mandates for health education programs and the role of nurses within these programs.  相似文献   
24.
We describe the functioning and well-being of patients with depression, relative to patients with chronic medical conditions or no chronic conditions. Data are from 11,242 outpatients in three health care provision systems in three US sites. Patients with either current depressive disorder or depressive symptoms in the absence of disorder tended to have worse physical, social, and role functioning, worse perceived current health, and greater bodily pain than did patients with no chronic conditions. The poor functioning uniquely associated with depressive symptoms, with or without depressive disorder, was comparable with or worse than that uniquely associated with eight major chronic medical conditions. For example, the unique association of days in bed with depressive symptoms was significantly greater than the comparable association with hypertension, diabetes, and arthritis. Depression and chronic medical conditions had unique and additive effects on patient functioning.  相似文献   
25.
Management of major colonic haemorrhage   总被引:2,自引:0,他引:2  
Major colonic haemorrhage remains a difficult diagnostic and therapeutic problem. We propose that those patients who continue to bleed after resuscitation are best served by immediate laparotomy. High flow antegrade irrigation and intra-operative colonoscopy can then be used to localize the site of bleeding and allow appropriate excisional surgery rather than blind colonic resection.  相似文献   
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The purpose of this paper is to discuss the potential for integrating surveillance techniques in reproductive epidemiology with geographic information system technology in order to identify populations at risk around hazardous waste sites. Environmental epidemiologic studies have had problems with estimating or measuring exposures to individuals, and of detecting effects when the exposure is low, but continuous. In addition, exposures around hazardous waste sites are complex and frequently involve chemical mixtures. The birth weight of human babies has been reported to be sensitive to many environmental influences. Birth weight can be analyzed as a continuous variable or as a dichotomous one using the standard cutpoint of 2500 g or less to indicate low birth weight. It has the potential to be a powerful surveillance tool since exposures to the fetus reflect maternal and paternal exposures. The advent of recent environmental regulations pertaining to hazardous waste sites has greatly increased the availability of environmental data for many sites. The major problem with incorporating these data into epidemiologic studies has been with the logistics of data management and analysis. Computer-assisted geographic information systems hold promise in providing capabilities needed to address the data management and analysis requirements for effective epidemiologic studies around to hazardous waste sites.  相似文献   
29.
One hundred twenty-seven infants less than 36 weeks of gestation (mean +/- SE = 31 +/- 3.2 weeks) were studied with echoencephalography to determine the incidence and complications associated with white matter necrosis. Ten infants (8%) developed cysts ten or more days after birth, indicating postnatal onset of white matter necrosis. Univariate analysis showed that postnatal white matter necrosis was significantly associated with maternal infection (other than urinary infection), respiratory distress syndrome, and longer requirement of an oxygen concentration greater than 40%. Forward logistic regression analysis showed postnatal white matter necrosis to be associated with maternal infection, chronic placental infarction, congenital pneumonia, and longer requirement of an oxygen concentration greater than 40%. Neurodevelopmental outcome was abnormal during infancy in 4 of the 6 survivors with postnatal white matter necrosis. Severe respiratory disease and maternal and/or fetal infection appear to increase the risk of the immature brain to white matter necrosis, predisposing the infants to subsequent neurodevelopmental delay.  相似文献   
30.
An in vitro method for obtaining pressure/volume curves from the lungs of small animals is described. The excised lungs were inflated and deflated with saline or air by a motor-driven syringe controlled by a microcomputer. The computer was programmed to display the curves in real time, correcting when necessary for the compressibility of air in the system. Volume compliance (K=dV/dP×1/V) was calculated by differentiating a polynomial fitted to the measured pressure/volume points. Repeatable curves were obtained from mice aged 24h (body weight 1·3±0·14g (SD), residual lung volume 8·43±1·5 μl (SD). A nonlinear decrease in differential compliance (K=dV/dP×1/V) with increasing strain was observed while the ratio Ksaline/Kair increased from 2·5 to 10 over the range of strains investigated (ε=1–5). The relative surface tension (calculated from the difference between the pressures required to inflate the air and saline-filled organs to a given volume) increased exponentially with increasing volume. We conclude that it is now possible to obtain reproducible pressure/volume curves for lungs with a residual volume of less than 10 μl, from animals weighing approximately 1·5 g and, from these curves, estimate airway compliance and surface tension.  相似文献   
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