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51.
The increased awareness of the incidence and risk of coronary heart disease (CHD) has increased the efforts of physicians to identify women with CHD as early as possible. Exercise electrocardiogram (ECG) testing and imaging have been used in this manner for men and women but represent unique challenges with regard to women. Exercise ECG testing, which determines the presence of coronary artery disease by the provocation of ST depression and chest pain, has a lower positive predictive value in women than in men of the same age. This is explained by a lower prevalence of CHD in female patients with symptoms and (to a lesser extent) by the reported lower sensitivity and specificity of the test in women as compared with men. Exercise nuclear isotope myocardial perfusion imaging and exercise echocardiography have higher reported specificity and sensitivity, and new imaging agents, contrast echo agents, and acquisition protocols have reduced the limitations of these studies in selected women. The value of the exercise ECG examination with regard to CHD event risk assessment is equal in men and women and should be incorporated into the clinical evaluation of appropriate women patients.  相似文献   
52.
BACKGROUND: Epidemiologic studies reveal that posttraumatic stress disorder (PTSD) is highly comorbid with both conduct disorder and major depression in men. The genetic and environmental etiology of this comorbidity has not been examined. METHODS: Data were analyzed from 6744 middle-aged male-male monozygotic and dizygotic twins from the Vietnam Era Twin Registry. Conduct disorder, major depression, and PTSD were assessed via telephone interview using the Diagnostic Interview Schedule for the DSM-III-R in 1992. Structural equation modeling was used to estimate additive genetic, shared environmental, and individual-specific environmental effects common and specific to conduct disorder, major depression, and PTSD. RESULTS: The association between conduct disorder and PTSD was explained primarily by common shared environmental influences; these explained 10% (95% confidence interval: 6%-17%) of the variance in PTSD. The association between major depression and PTSD was largely explained by common genetic influences; these explained 19% (95% confidence interval: 11%-26%) of the variance in PTSD. CONCLUSIONS: Our findings suggest that different etiologic mechanisms explain the association of conduct disorder and major depression with PTSD in male veterans. If replicated in other populations, results suggest research aimed at identifying specific genetic and environmental factors that influence PTSD may benefit from starting with those that have been more consistently and strongly associated with major depression and conduct disorder.  相似文献   
53.
The biological and biomechanical properties of normal fibulae, fibulae that had had a sham operation, and both vascularized and non-vascularized autogenous grafts were studied in dogs at three months after the operation. The study was designed to quantify and correlate changes in these properties in orthotopic, stably fixed, weight-bearing grafts and to provide a baseline for additional studies of allografts. The grafts were eight centimeters long and internally fixed. The mechanical properties of the grafts were studied by torsional testing. Metabolic turnover of the grafts was evaluated by preoperative labeling of the dogs with 3H-tetracycline for resorption of bone mineral and with 3H-proline for turnover of collagen. Cortical bone area and porosity were measured. Postoperative formation of bone was evaluated by sequential labeling with fluorochrome. The vascularized grafts resembled the fibulae that had had a sham operation and those that had not had an operation with regard to the total number of osteons and the remodeling process, as measured both morphometrically and metabolically. The vascularized grafts were stronger and stiffer than the non-vascularized grafts and were not different from the bones that had had a sham operation. In contrast, the non-vascularized grafts were smaller, weaker, less stiff, and more porotic, had fewer osteons, and demonstrated increased turnover and resorption compared with the vascularized grafts, the bones that had had a sham operation, and the bones that had not been operated on.  相似文献   
54.
55.
We report the first case of a unilateral microcysticMeesmann‘s epithelial dystrophy, observed in the left cornea of a 43-year-old patient. The diagnosis was verified histologically by the unilateral occurrence of a ’peculiar substance‘ within epithelial cysts and within the cytoplasm of the corneal epithelial cells. In an attempt to resolve thepatient‘s frequent corneal erosions, we performed an autologous stem cell transplantation from the non-involved right eye. The results are, so far, satisfactory. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
56.
Nocturnal pains of the leg were the only complaint of a 2 1/2-year-old girl with recurrent dislocations of the left hip. Unusual movement during sleep probably caused the dislocations. This case represents a benign entity characterized by spontaneous or voluntary posterior dislocations of the femoral head in young children without other significant connective tissue abnormalities.  相似文献   
57.
Erythema multiforme due to herpes simplex: treatment with oral acyclovir   总被引:1,自引:0,他引:1  
We have reported a case of severe erythema multiforme caused by outbreaks of recurrent HSV-2 infection. The EM was debilitating and responded to the treatment of HSV with oral acyclovir. On stopping the oral acyclovir, the HSV and the EM both recurred. We recommend a trial of oral acyclovir in cases of severe EM caused by recurrent HSV.  相似文献   
58.
Background: Available phosphate binders contain aluminium or calcium which can be associated with undesirable effects. RenaGel®, cross-linked poly(allyl-amine hydrochloride) is a non-absorbed phosphate binding polymer, free of calcium and aluminium. We conducted this study to examine the safety and phosphate binding efficacy of RenaGel in volunteers. Method: During 18 days (days 0-17) at the clinical study unit, 24 subjects consumed a phosphate-controlled diet designed to provide 37.5 mmol (1200 mg) elemental phosphorus per day. From the morning of day 5 to the morning of day 9, urine and faeces were collected. Average base line urine and faecal phosphorus contents were determined. On days 9-16, the subjects received either RenaGel 1 g, 2.5 g, or 5 g or placebo three times per day immediately prior to the meals. From the morning of day 13 to the morning of day 17, urine and faeces were again collected and phosphorus contents on treatment were determined. Results: RenaGel inhibited dietary phosphate absorption as measured by a decline in average daily urinary phosphorus excretion and an increase in average daily fecal phosphorus excretion. Average urine phosphorus contents on treatment were 2.7.2 mmol (870 mg) per day in the placebo group vs 23.8 mmol (762 mg), 19.5 mmol (625 mg), and 16.6 mmol (530 mg) per day in the renaGel 1-g, 2.5-g, and 5-g groups. Average daily faecal phosphorus content on treatment was markedly higher in the RenaGel 5-g group, 19.1 mmol (611 mg) per day vs 10.7 mmol (342 mg) per day for the placebo group. RenaGel also decreased total serum cholesterol by 0.71 mmol/L (27.5 mg/dl), 0.55mmol/l (21.3 mg/dl), and 1.08 mmol/l (41.8 mg/dl for the RenaGel 1-g,and 5-g groups. RenaGel was well tolerated with adverse events similar to placebo. Conclusion: RenaGel is a safe, effective, and well tolerated phosphate binder in normal volunteers. The degree of phosphate binding is consistent with its potential use as a phosphate binder in renal failure patients.  相似文献   
59.
The diet-health message for the 1990s has become complex, changing from the simple directives of previous decades as scientific evidence has evolved. If today's consumers are more knowledgeable, they are also more confused. The confusion stems not only from the complexity of the message, but also from the fact that the various groups and organizations developing it respond to the challenge from their own perspectives. Added to this are the constraints of the various media (print, radio, and television) that deliver the message. For consumers, the result has been not only confusion but, at times, outright rejection of resonable recommendations. The more that health professionals in academia, government, and voluntary organizations, food producers, and health reporters can agree on a set of clear, consistent, focused, and positive messages based on current scientific knowledge, the sooner recommendations for a healthful diet will be accepted and followed.  相似文献   
60.
OBJECTIVES: This study developed a new acquired immunodeficiency syndrome (AIDS) severity system by including diagnostic, physiological, functional, and sociodemographic factors predictive of survival. METHODS: Three-hundred five persons with AIDS in Boston were interviewed; their medical records were reviewed and vital status ascertained. RESULTS: Overall median (+/- SD) survival for the cohort from the first interview until death was 560 +/- 14.4 days. The best model for predicting survival, the Boston AIDS Survival Score, included the Justice score (stage 2 relative hazard [RH] = 1.25, 95% confidence interval [CI] = 0.80, 1.96; stage 3 RH = 1.76, 95% CI = 1.15, 2.70), a newly developed opportunistic disease score (Boston Opportunistic Disease Survival Score; stage 2 RH = 1.35, 95% CI = 0.90, 2.02; stage 3 RH = 2.10, 95% CI = 1.38, 3.18), and measures of activities of daily living (any intermediate limitations, RH = 1.84, 95% CI = 1.05, 3.21; any basic limitations, RH = 2.60, 95% CI = 1.44, 4.69). This model had substantially greater predictive power (R2 = .17, C statistic = .68) than the Justice score alone (R2 = .09, C statistic = .61). CONCLUSIONS: Incorporating data on clinically important events and functional status into a physiologically based system can improve the prediction of survival with AIDS.  相似文献   
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