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991.
The average number of visits to a physician made by a sample of 351 residents of homes insulated with urea formaldehyde foam insulation in Montreal in the one year period before exposure was 5.25, and in the year following 5.62, an increase of 7 per cent (odds ratio 1.07, 95% CI = 1.00, 1.15). The increase in visits in the post insulation year was limited to subjects who had the product installed in the winter (OR = 1.48, 95% CI = 1.18,1.85), and was not seen for study subjects who insulated their homes during other seasons of the year.  相似文献   
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Acute hypoxic preconditioning (AHPC) can confer neuroprotection from global cerebral ischemia such as cardiac arrest. We hypothesize that acute neuroprotection by AHPC will be detected early by quantitative EEG (qEEG) entropy analysis after asphyxial cardiac arrest (aCA). Cerebral ischemia lowers EEG signal randomness leading to low entropy. A qEEG entropy index defined as the duration when the entropy measure is 15% below uninjured baseline entropy is used as a measure of injury. We compared 3 groups of adult Wistar rats: (1) untreated controls that were subjected to 5 min of aCA and were resuscitated (n = 5); (2) AHPC-treated group with 10% FI O2 for 30 min, then 25 min of room air, 5 min of aCA followed by resuscitation (n = 5); and (3) a surgical sham group (no aCA) (n = 3). Functional outcome was assessed by neurodeficit score (NDS) which consisted of level of consciousness, cranial nerve, motor-sensory function, and simple behavioral tests (best = 100 and brain dead = 0). We found that increasing entropy index of injury at 0-5 h from return of spontaneous circulation (ROSC) is associated with worsening NDS at 24 h (linear regression: r = 0.81, P < 0.001). The NDS of the group sham (84.7 +/- 2.8) (mean +/- SEM) and AHPC group (84.6 +/- 2.9, P > 0.05) was better than control injury group (52.2 +/- 8.4, P < 0.05) (ANOVA with Tukey test). We therefore conclude that AHPC confers acute neuroprotection at 24 h, which was detected by qEEG entropy during the first 5 h after injury.  相似文献   
996.
The isolated unilateral absence of a proximal pulmonary artery is a rare congenital lesion with a diverse clinical presentation. If the connecting ductus arteriosus closes after birth, the ipsilateral pulmonary artery will lose its source of blood supply, resulting in hypoplasia or obliteration of intrapulmonary vessels. Despite a seemingly benign early clinical course, a significant number of untreated patients will develop pulmonary hypertension, hemoptysis, and recurrent respiratory infections. Early detection and surgical repair provides restoration of physiologic pulmonary circulation, regression of pulmonary hypertension, and the potential for normal distal pulmonary vascular development.  相似文献   
997.
Nonalcoholic fatty liver disease (NAFLD) is emerging as a component of the metabolic syndrome, although it is not known whether markers of NAFLD, including elevated concentrations of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALK), predict the development of metabolic syndrome. Our objective was to investigate the associations of elevated AST, ALT, and other liver markers, including C-reactive protein (CRP), with incident National Cholesterol Education Program-defined metabolic syndrome among 633 subjects in the Insulin Resistance Atherosclerosis Study who were free of metabolic syndrome at baseline. Insulin sensitivity (Si) and acute insulin response (AIR) were directly measured from the frequently sampled intravenous glucose tolerance test among African-American, Hispanic, and non-Hispanic white subjects aged 40-69 years. After 5.2 years, 127 individuals had developed metabolic syndrome. In separate logistic regression models adjusting for age, sex, ethnicity, clinic, and alcohol consumption, subjects in the upper quartiles of ALT, ALK, and CRP were at significantly increased risk of incident metabolic syndrome compared with those in the lowest quartile: ALT, odds ratio 2.50 (95% CI 1.38-4.51); ALK, 2.28 (1.24-4.20); and CRP, 1.33 (1.09-1.63). Subjects in the upper quartile of the AST-to-ALT ratio were at significantly reduced metabolic syndrome risk (0.40 [0.22-0.74]). After further adjustment for waist circumference, Si, AIR, and impaired glucose tolerance, the associations of ALT and the AST-to-ALT ratio with incident metabolic syndrome remained significant (ALT, 2.12 [1.10-4.09]; the AST-to-ALT ratio, 0.48 [0.25-0.95]). These associations were not modified by ethnicity or sex, and they remained significant after exclusion of former and heavy drinkers. In conclusion, NAFLD markers ALT and the AST-to-ALT ratio predict metabolic syndrome independently of potential confounding variables, including directly measured Si and AIR.  相似文献   
998.
BACKGROUND AND OBJECTIVE: Persons experiencing changes in their physical health may change their values and rerate the importance of basic elements of health-related quality of life (HRQL), a process known as response shift. Developing an estimator of HRQL that differentiates between objective change and response shift is essential for the interpretation of the results. The purpose of the present article was to contrast three methodologic approaches for evaluating response shift to develop a proposed set of HRQL measurement recommendations under circumstances where response shift is expected to occur. METHODS: The three approaches compared were a structural equation modeling (SEM) technique, the then test, and an individualized approach. The data collection procedures for these methods were incorporated into a poststroke randomized controlled trial. RESULTS: The SEM did not show a response shift, contrary to the results of the then test and the individualized approaches. We discuss factors that effect the selection of a methodologic approach including feasibility, subjects' memory and more advanced cognitive tasks, and whether response shift was evaluated at the group or individual level. CONCLUSION: The evaluation of response shift is an integral part of HRQL evaluations, and further comparisons between methodologic approaches are needed.  相似文献   
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Small percentages of anorectal abscesses and of chronic fistula in ano are supralevator, resulting from a high intermuscular abscess caused by infected anal glands or chronic ulcer of the anus. The disease is not to be confused with a pelvic abscess caused by other factors. The recommended treatment is internal sphincterotomy to permit drainage at the site of perforation in the longitudinal muscle into the rectum. On rare occasions, in critically ill patients, additional drainage of the pelvic abscess may be necessary through the fossa ischiorectalis or by a lumbar-retroperitoneal space approach.  相似文献   
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