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71.

Background  

This study compared the prognostic value of exercise single-photon emission computed tomographic (SPECT) thallium imaging with that of treadmill exercise score in medically treated patients with coronary artery disease (CAD)  相似文献   
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Colonoscopy has been advocated by some investigators as the most appropriate means of screening asymptomatic patients with a positive family history of colorectal cancer. However, results of such screening have been widely disparate. The purpose of this study was to evaluate the yield of colonoscopy in a cohort of completely asymptomatic individuals with one or two first-degree relatives with a history of colorectal cancer and to compare this yield with that of colonoscopy in a group of patients with apparent anal bleeding. Patients with possible genetic disorders, such as familial polyposis, were excluded. A total of 160 asymptomatic patients and a comparison group of 137 patients with nonacute anorectal bleeding underwent colonoscopy. Colonoscopy was completed in 143 of the 160 study patients (89 percent) and in all of the comparison patients and did not result in any complications. Twenty-two adenomas were found in 17 study patients (10.6 percent); 16 of the 22 adenomas were less than 1 cm in size. In the comparison group, eight adenomas were identified (5.8 percent of patients). No cancers were identified. The difference in polyp frequency between groups was not significant. The relatively low yield of colorectal neoplasms discovered at colonoscopy in this study may in part be due to the small sample size or to the strict criteria used to define these asymptomatic patients but does not lend strong support to the notion that colonoscopy is an appropriate first step in screening the asymptomatic patient with one or two first-degree relatives with colon cancer.  相似文献   
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In the cerebellar type of multiple system atrophy (MSA-C), the burden of pathological changes involves the cerebellum and its associated brainstem structures in the basis pontis and the inferior olivary nucleus, and as a result, the clinical phenotype is dominated early on by the cerebellar dysfunction. We report our clinical and post mortem findings in a patient with MSA-C who exhibited pathological laughter in the absence of any congruent changes of mood. A review of the clinical notes of 27 other patients with MSA-C revealed a problem with pathological laughter, or crying, or both in 9 more patients. Our finding of about 36% occurrence suggests that the problem of dysregulation of emotional expression is more prevalent in MSA-C than the paucity of reports in the literature suggests. Our findings are consistent with the view that the cerebellum and its interconnected structures may be involved in the regulation of emotional expression.  相似文献   
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OBJECTIVE: To determine how knowledgeable physicians are regarding the toxic effects and drug interactions of herbal remedies. METHODS: An anonymous voluntary demographic survey and 16-question, multiple-choice quiz was distributed at educational meetings of emergency medicine and internal medicine physicians. The primary outcome measures were to determine whether significant associations existed between quiz scores and the amount of clinical experience, or between quiz scores and self-assessed familiarity with the topic of herbal toxicities and adverse herb-drug interactions. RESULTS: A total of 142 surveys and quizzes were completed by 59 attending physicians, 57 resident physicians, and 26 medical students. The mean subject score on the quiz was only slightly higher than would have occurred from random guessing. Neither the amount of the subjects' clinical experience, nor their self-assessed familiarity with herbal toxicities and drug interactions correlated significantly with the score on the quiz. CONCLUSION: The physicians and medical students surveyed had little training in herbal toxicities and drug interactions. They generally rated their familiarity with these topics as 'poor', and their scores on the quiz bore out this assessment as correct. Educational efforts might improve physician knowledge of the adverse effects of herbal remedies.  相似文献   
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Background Several clinical decision rules (CDRs) have been validated for pretest probability assessment of pulmonary embolism (PE), but the authors are unaware of any data quantifying and characterizing their use in emergency departments. Objectives To characterize clinicians' knowledge of and attitudes toward two commonly used CDRs for PE. Methods By using a modified Delphi approach, the authors developed a two‐page paper survey including 15 multiple‐choice questions. The questions were designed to determine the respondents' familiarity, frequency of use, and comprehension of the Canadian and Charlotte rules. The survey also queried the frequency of use of unstructured (gestalt) pretest probability assessment and reasons why physicians choose not to use decision rules. The surveys were sent to physicians, physician assistants, and medical students at 32 academic and community hospitals in the United States and the United Kingdom. Results Respondents included 555 clinicians; 443 (80%) work in academic practice, and 112 (20%) are community based. Significantly more academic practitioners (73%) than community practitioners (49%) indicated familiarity with at least one of the two decision rules. Among all respondents familiar with a rule, 50% reported using it in more than half of applicable cases. A significant number of these respondents could not correctly identify a key component of the rule (23% for the Charlotte rule and 43% for the Canadian rule). Fifty‐seven percent of all respondents indicated use of gestalt rather than a decision rule in more than half of cases. Conclusions Academic clinicians were more likely to report familiarity with either of these two specific decision rules. Only one half of all clinicians reporting familiarity with the rules use them in more than 50% of applicable cases. Spontaneous recall of the specific elements of the rules was low to moderate. Future work should consider clinical gestalt in the evaluation of patients with possible PE.  相似文献   
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BACKGROUND AND OBJECTIVE: The adverse effects of untreated seasonal allergic rhinitis (AR) on performance in the workplace, school, and home are poorly understood. To delineate more clearly the impact and consequences of the disease on performance, the effect of symptomatic AR on vigilance and a wide range of cognitive functions was investigated. METHODS: A battery of automated neuropsychological tests was administered to asymptomatic adult subjects with histories of AR. Subjects were randomized to either a symptomatic or to an asymptomatic group. Subjects in the symptomatic group were exposed to ragweed pollen in a controlled exposure setting until they demonstrated predetermined severities of AR symptoms. Subjects in the asymptomatic group were not exposed to ragweed pollen in the environmental unit and retained a minimum symptom profile. The battery of cognitive measures was re-administered to both groups. RESULTS: AR had major adverse impacts on measures of vigilance. Further, AR adversely affected a broad range of cognitive functions. Specifically, subjects with AR symptoms demonstrated longer response times and decreased efficiency on measures of working memory, psychomotor speed, reasoning/computation, and divided attention as compared with asymptomatic subjects. CONCLUSIONS: In addition to decreased vigilance, AR was associated with decrements in speed and efficiency across several cognitive domains. This is similar to findings in research on medications and medical conditions that cause sedation. Findings may represent a link between AR and poor productivity/personal safety among AR sufferers. This suggests that these results have implications with regard to public health.  相似文献   
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