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1.
A patient developed a huge diaphragmatic hernia following laparoscopic gastric banding. Almost the entire stomach was incarcerated within the left chest. Segmental necrosis of the greater curvature of the stomach necessitated partial gastrectomy. The postoperative course was uneventful. The etiology, diagnosis and treatment of this previously undescribed complication of laparoscopic gastric banding are addressed in relation to the present case.  相似文献   
2.
The epidemiology of sudden death, the etiology of inflight sudden incapacitation, and the influence of pilot age and experience on air accident rates are reviewed in order to determine the aeromedical emphasis needed to minimize accidents. Sudden deaths in men over age 35 are nearly all due to coronary artery disease, whereas in those under 35 years they are mostly due to hypertrophic cardiomyopathy. The incidence of fatal accidents from human error is, however, far greater than that from physical illness. Since inexperienced pilots have a 2-3 times increased incidence of mishaps due to pilot error, the estimated risk of disease related in-flight sudden incapacitation should be balanced by consideration of pilot experience. Therefore, it may be preferable to grant waivers to experienced pilots with an increased incidence of disease-related inflight sudden incapacitation than to replace them with novices. We conclude that overly strict medical criteria may paradoxically increase accident rates.  相似文献   
3.
In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group.  相似文献   
4.
Most U.S. medical schools offer courses in the behavioral and social sciences (BSS), but their implementation is frequently impeded by problems. First, medical students often fail to perceive the relevance of the BSS for clinical practice. Second, the BSS are vaguely defined and the multiplicity of the topics that they include creates confusion about teaching priorities. Third, there is a lack of qualified teachers, because physicians may have received little or no instruction in the BSS, while behavioral and social scientists lack experience in clinical medicine. The authors propose an approach that may be useful in overcoming these problems and in shaping a BSS curriculum according to the institutional values of various medical schools. This approach originates from insights gathered during their attempts to teach various BSS topics at four Israeli medical schools. They suggest that medical faculties (1) adopt an integrative approach to learning the biomedical, behavioral, and social sciences using Engel's "biopsychosocial model" as a link between the BSS and clinical practice, (2) define a hierarchy of learning objectives and assign the highest priority to acquisition of clinically relevant skills, and (3) develop clinical role models through teacher training programs. This approach emphasizes the clinical relevance of the BSS, defines learning priorities, and promotes cooperation between clinical faculty and behavioral scientists.  相似文献   
5.
How medical students are taught physical examination (PE) skills appears to have changed little since the 1950s. Textbooks are organized according to organ systems and describe methods of eliciting and recording history and PE data using a routine format. In many medical schools, the preclinical teaching programs for clinical examination skills similarly emphasize an orderly collection of data. Teaching students to use diagnostic reasoning is postponed until students have learned history-taking and PE skills. The authors propose three modifications to this educational approach. First, rather than performing the clinical examination using a routine format, students should be encouraged to form diagnostic hypotheses early on while listening to the patient's narrative, and conduct the subsequent search for history and PE data in a reflective way in order to confirm or refute these hypotheses. Second, the authors propose that interviewing patients and conducting the PE be taught by one-on-one tutoring until students achieve mastery. Last, they suggest that the PE be guided not only by students' diagnostic hypotheses, but also by patients' expectations. These modifications are consistent with current trends in medical education that encourage a reflective practice and problem-based learning (PBL), and they also introduce medical students to the precepts of clinical reasoning. The authors suggest that challenging students to seek specific physical findings may increase the likelihood of detecting findings when they are present, and may transform patient interviewing and conducting the PE from routine activities into intellectually exciting experiences.  相似文献   
6.
Osteonecrosis of the femoral head was produced in rats by cutting the ligamentum teres and incising the cervical periosteum. As of the second postoperative week, fibrous tissue pervaded the necrotic epiphyses, macrophages and osteoclasts removed the debris, osteoblasts deposited lamellar-fibred and woven-fibred intramembranous bone, and remodeling began. In 16% of the rats killed during the 2nd postoperative week, the epiphyses contained big fragments of necrotic bone enclosed by densely packed, capillary-sized vessels. Ingrowth of this hypervascularized, pyogenic granuloma-like tissue is presumably due to the presence of excessive growth factors, reflecting an exaggerated pathophysiological reaction within the framework of organization of the necrotic epiphyses.  相似文献   
7.
Blood pressure response to exercise as a predictor of hypertension   总被引:1,自引:0,他引:1  
Published studies of the blood pressure response to exercise were reviewed to assess the probability of future hypertension in a subject with a "hypertensive" response to exercise. The reviewed data indicate that the sensitivity of a hypertensive response to exercise for future hypertension varied between 16% and 60%, and the specificity between 53% and 95%. The prevalence of hypertension on follow-up among normotensive subjects with a hypertensive response to exercise testing was 2.06 to 3.39 times higher than that among subjects with a normotensive response. Therefore, blood pressure response to exercise does have a predictive value for future hypertension. However, this predictive value is limited, since 38.1% to 89.3% of those with a hypertensive response to exercise did not have hypertension on follow-up, and a normotensive response only marginally reduced the risk of future hypertension. The use of exercise testing as a predictor of hypertension is still in need of experimental development and confirmation.  相似文献   
8.
Objective The aim of this study was to assess the presence of dysautonomia, as manifested in abnormal cardiovascular reactivity, in patients with familial Mediterranean fever (FMF).Methods Fifty-five consecutive patients with FMF and 23 age- and sex-matched healthy controls were evaluated. Cardiovascular reactivity was studied: (1) using recordings of blood pressure (BP) and heart rate (HR) during 10 min of recumbence and 30 min of head-up tilt test to identify clinical endpoints and (2) during tilt-test, identifying parameters acting as independent predictors of FMF reactivity and enabling computation of a cardiovascular reactivity score (CVRS).Results Clinically, vasovagal reaction, postural tachycardia syndrome, and/or orthostatic hypotension were observed in ten patients (18.1%). Utilizing a derived equation, the group average CVRS in FMF was 5.83±1.78 (healthy group –7.60±5.41) (P=<0.0001). A CVRS of >3.25 was associated with FMF, with 98% sensitivity and 100% specificity.Conclusion A very high percentage of FMF patients exhibit abnormal cardiovascular reactivity which is clinically occult but can be detected on autonomic challenge and application of the CVRS.  相似文献   
9.
The prognostic significance of age, sex, ethnic origin and various laboratory data was studied retrospectively in 69 patients with multiple myeloma using conventional statistical tests and the multiple regression computerized analysis. The conventional statistical analysis confirmed that age, anemia, uremia, hypoalbuminemia, hyperglobulinemia, hyperuricemia and IgA lambda type myeloma were associated with a poor prognosis. The multiple regression analysis indicated that age and blood urea nitrogen levels were the only variables which significantly affect the survival of patients with multiple myeloma. A correlation was found between blood urea nitrogen levels and other laboratory data of apparent prognostic value. The differences between our results and those of other authors are discussed and it is suggested that they may, in part, be due to the fact that the interplay between the various prognostic variables was not exposed in other studies.  相似文献   
10.
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