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51.
The literature addressing the mental health of homeless children is critically reviewed. Higher rates of behavioral, emotional, and cognitive problems have been reported for this population, but research results are qualified by significant methodological problems. Minimal attention has been given to the development and evaluation of specific intervention and prevention strategies. Recommendations are made for conducting research that will overcome previous methodological problems and focus more directly on identifying risk and protective mechanisms within the population of children exposed to homelessness.  相似文献   
52.
The management of patients through the use of evidence-based medicine has become the 'mantra' of medicine within many Western countries. Evidence-based medicine is aimed at providing the best objective, scientific care to all patients, and reducing as far as possible patients' risks of disease and complications from disease. Based on family physicians' discussions of the use of evidence-based recommendations for two cardiac diseases, this paper explores how subjectively-based trust enters into family physicians' decision to use evidence-based medicine. In addition, we show how trust influences physicians' work of recommending evidence-based medicine to patients, and physicians' perceptions of why patients follow recommendations aimed at risk reduction. We conclude that although much of the current discussion about evidence-based medicine assumes a 'rational' model of physician behaviour based on the application of the 'best objective scientific' results, subjectively-based perceptions of trust influence physician practices, and point to the need to understand the power of relational issues in influencing physician practices even when utilizing evidence-based knowledge.  相似文献   
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The chief aim of this study was to maximize flap survival by counteracting the pathophysiological changes occurring during ischemia-reperfusion. Rabbit epigastric skin flaps given 21 hours of ischemia were infused intra-arterially with selected drugs at the start of reperfusion. Compared with control infused ischemic flaps, which had a 33% survival rate on day 7 post-ischemia, significant improvement was found with vasodilators nitrendipine (61%) and prostacyclin (65%) and the thrombolytic agent urokinase (65%); marginal improvement with the free radical scavenger desferrioxamine (53%); but no change with streptokinase (44%), heparin (21%), and ATP-MgCl2 (35%). A drug mixture comprising all of these agents except streptokinase and urokinase produced 87% survival, suggesting an additive effect. Biochemical assays on skin homogenates and blood implicated oxygen free radicals, neutrophil infiltration, and thromboxane in flap failure. These results imply that multiple factors are responsible for ischemic flap failure and that a mixture of drugs needs to be infused to counteract all of the detrimental changes. © 1994 Wiley-Liss, Inc.  相似文献   
55.
Body temperature monitoring in subjects with delayed sleep phase syndrome   总被引:2,自引:0,他引:2  
To clarify the circadian aspects of delayed sleep phase syndrome (DSPS) in 4 patients with DSPS, we recorded polysomnograms and rectal temperature before and after chronotherapy. The time interval (2.7 h) between sleep onset and rectal temperature minimum before chronotherapy was shorter than the time interval after chronotherapy (5.3 h). Before chronotherapy, the period of rectal temperature rhythm was 24.7 h. After chronotherapy, the period of rectal temperature rhythm was 24.0 h. These findings lead to the conclusion that in DSPS there is a weakened mechanism of entrainment similar to that in non-24-hour sleep-wake syndrome.  相似文献   
56.
Transcatheter arterial infusion chemotherapy is one of the most useful therapeutic procedures for gynecologic malignancies. Recently, several reports have been published about Angiotensin II-induced hypertension chemotherapy and the efficacy of the method, but there have been no reports to evaluate an application for gynecologic malignancies. We evaluate the usefulness of the method for gynecologic malignancies demonstrating the changes of hemodynamics of the tumor using 81mKr scintigraphy. Thirteen patients with pathologically confirmed gynecologic malignancies were evaluated by angiography and continuous infusion of 81mKr via the catheter with and without Angiotensin II. At first, continuous infusion of 81mKr was performed under the superselective catheterization of the uterine artery. The radioactivities in the ROI were counted. Then, withdrew the catheter from the uterine artery to the internal iliac artery, and again continuously infused 81mKr and counted the radioactivities in the same ROI. Finally, keeping the catheter in the internal iliac artery, Angiotensin II and 81mKr were infused simultaneously. And counted the radioactivities. The radioactivities were highest when the catheter tip was placed in uterine arteries and lowest when the catheter tip was placed in internal iliac arteries. But radioactivities in the ROIs were definitely increased when Angiotensin II was used, even if the catheter tip was keeping in the internal iliac arteries. The optimal catheter position of transcatheter arterial chemotherapy for gynecologic malignancies is at proximal uterine artery. Since Angiotensin II-induced hypertension may increase blood flow of tumors, it seems to have indication for post-operative cases, highly advanced cases and cases with difficulties to perform superselective catheterization.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
57.
The lactic dehydrogenase (LDH) level in plasma and the clearance of LDH in C.B-17 scid (severe combined immunodeficiency; SCID) mice were compared with those in C.B-17 or BALB/cCrSlc mice with or without lactic dehydrogenase virus (LDV) infection. The resting enzyme level in SCID mice showed little difference from that in C.B-17 or BALB/cCrSlc mice. The degree of increased plasma LDH level in SCID mice was lower than that in C.B-17 and BALB/cCrSlc mice after LDV infection. To assess the mechanisms of decrease in LDH elevation in SCID mice infected with LDV, virus replication was compared in SCID and BALB/cCrSlc mice. The infectivity titre of plasma in SCID mice was higher (more than 10 times) than that in BALB/cCrSlc mice. Moreover, the percentage of virus antigen positive Kupffer cells was higher in SCID mice than that in BALB/cCrSlc mice. The level of endogenous LDH release as a result of carbon tetrachloride treatment was similar in the SCID and BALB/cCrSlc mice. The clearance rate of endogenous LDH was greater in SCID mice than in BALB/cCrSlc mice with or without LDV infection. The rate of clearance of intravenously injected porcine LDH-5, but not porcine LDH-1, was enhanced in SCID mice as compared with that in BALB/cCrSlc mice. Furthermore, carbon clearance was higher in SCID mice than that in BALB/cCrSlc mice. These results suggest that the smaller increase of plasma LDH after infection might be due, at least in part, to the enhanced LDH-5 clearance function by macrophages in SCID mice.  相似文献   
58.
We report a case of massive cerebrospinal fluid (CSF) leakage where the tracer injected intra-thecally for radionuclide cisternography was later visualized in the bowel as well as the nasopharynx. We discuss the potential implications of this finding in patients with CSF leaks. A brief review of the diagnosis of CSF leaks is included.  相似文献   
59.
A 46-year-old man was referred to our hospital because of prosthetic valve regurgitation. Eight years previously he had undergone aortic valve replacement because of aortic regurgitation due to infective endocarditis. At reoperation, we found prosthetic valve endocarditis and discrete subaortic stenosis. The obstructing fibrous tissue was resected and the aortic valve was replaced. Because discrete subaortic stenosis is usually located just below the aortic valve, the aortic valve cusps are liable to become thickened by the jet through the discrete stenosis and thus are vulnerable to infective endocarditis. It is pointed out that care must be taken not to overlook discrete subaortic stenosis in the presence of other associated cardiac disorders.  相似文献   
60.
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