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OBJECTIVE: To study the clinical profile and diagnostic methods in patients with symptomatic pulmonary embolism (PE). METHODS: Prospective assessment of clinical features, radiology and outcome of patients presenting with symptomatic PE over an 18-month period. RESULTS: During study period, 24 patients with a mean age of 39 +/- 12.1 years were diagnosed to have symptomatic pulmonary embolism. Dyspnoea (91.7%) and cough (58.3%) were the predominant complaints. Spiral computed tomographic pulmonary angiography (CTPA) was performed in 21 (87.5%) patients and perfusion scans in 14 (58.4%) patients. Echocardiography performed in all patients revealed evidence of pulmonary artery hypertension and right ventricular dyskinesia in 20 (83.3%) and 15 (62.5%) patients, respectively. Thrombolysis with streptokinase was performed in 14 (58.3%) patients. All patients received low molecular weight heparin followed by warfarin. Of the 24 patients, 20 (83.3%) were discharged and are under regular follow-up; four patients died. CONCLUSIONS: Pulmonary embolism is a common problem and can be easily diagnosed provided it is clinically suspected. Early diagnosis and aggressive management is the key to successful outcome.  相似文献   
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Clinical instructors in health care disciplines are charged with engaging students in experiential learning wherein respect and cultural sensitivity is applied. This article reports on the results of 3 diversity workshops conducted for clinical preceptors and field instructors from various disciplines. The workshops were developed in response to students’ growing concerns that their academic learning experiences were negatively affected by dissatisfying management of differences between students, faculty, and preceptors with respect to ethno‐racial group membership, socioeconomic level, and degree of privilege and power. The workshops included a didactic session that presented basic principles of social and health equity followed by small‐group reflection about various ethical and moral dilemmas that were presented in clinical education scenarios. Examples of discrimination on a variety of levels were addressed in these workshops, including race, ethnicity, immigration status, sexual orientation, religion, body size and appearance, ability, age, socioeconomic class, religious faith, and gender. The group exercises and discussion from these sessions provided valuable insight and approaches to difficult but common areas of discomfiture encountered in the clinical teaching setting. This article presents the findings from participants of these diversity workshops in order to encourage the application of equity principles into clinical teaching in midwifery and other health care education contexts.  相似文献   
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Background: In the present study, we have evaluated the use of electron microscopy in subtyping pulmonary adenocarcinomas, comparing the ultrastructural findings with the diagnosis rendered by light microscopy. Materials and Methods: The gross and histologic features of 16 autopsy cases of pulmonary adenocarcinoma were analyzed and compared with electron microscopic features. The cytologic phenotypes of these cases of well-differentiated pulmonary adenocarcinoma were determined by electron microscopic examination. More than 200 cells in each case were examined, and the tumors were classified according to the predominant feature noted. Results: Eight cases were of Clara cell origin and one case each of type II pneumocyte and bronchial surface cell type. The remaining 6 cases lacked definite discernible features of differentiation towards any specific cell type, other than presence of small nuclear clefts in occasional nuclei. Tumors with Clara cell differentiation were low cuboidal with apical snouts. Type II pneumocyte tumor failed to reveal any characteristic definable as light microscopic feature. Conclusion: Ultrastructural examination is the only definite means of identification of various cell types in the respiratory epithelium and hence forms an invaluable tool in classification of pulmonary adenocarcinoma.  相似文献   
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Glioblastomas and brain metastases demonstrate avid uptake of 2‐[18F]fluoro‐2‐deoxyglucose by positron emission tomography and display perturbations of intracellular metabolite pools by 1H MRS. These observations suggest that metabolic reprogramming contributes to brain tumor growth in vivo. The Warburg effect, excess metabolism of glucose to lactate in the presence of oxygen, is a hallmark of cancer cells in culture. 2‐[18F]Fluoro‐2‐deoxyglucose‐positive tumors are assumed to metabolize glucose in a similar manner, with high rates of lactate formation relative to mitochondrial glucose oxidation, but few studies have specifically examined the metabolic fates of glucose in vivo. In particular, the capacity of human brain cancers to oxidize glucose in the tricarboxylic acid cycle is unknown. Here, we studied the metabolism of human brain tumors in situ. [U‐13 C]Glucose (uniformly labeled glucose, i.e. d ‐glucose labeled with 13 C in all six carbons) was infused during surgical resection, and tumor samples were subsequently subjected to 13C NMR spectroscopy. The analysis of tumor metabolites revealed lactate production, as expected. We also determined that pyruvate dehydrogenase, turnover of the tricarboxylic acid cycle, anaplerosis and de novo glutamine and glycine synthesis contributed significantly to the ultimate disposition of glucose carbon. Surprisingly, less than 50% of the acetyl‐coenzyme A pool was derived from blood‐borne glucose, suggesting that additional substrates contribute to tumor bioenergetics. This study illustrates a convenient approach that capitalizes on the high information content of 13C NMR spectroscopy and enables the analysis of intermediary metabolism in diverse cancers growing in their native microenvironment. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns.  相似文献   
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