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Liposarcomas are extremely rare in the mediastinum. They may achieve considerable size before causing any symptoms. Mediastinal liposarcomas may invade surrounding structures like the pericardium or the superior vena cava. Complete surgical excision is the optimal treatment in resectable cases. Excision of adjacent structures like the pericardium may be needed if the tumor infiltrates them. We report on a case of a giant liposarcoma of the mediastinum involving both hemithoraces and extending into the neck, which was successfully managed by complete surgical excision.  相似文献   
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Alzheimer's disease (AD) patients often present with concurrent major depression (MD). To investigate the reasons for this comorbidity, e.g. MD being a risk factor for AD, or both diagnoses having a common neurobiology, the temporal relationship between the first onset of AD and of MD during lifetime was investigated-57 out of 146 AD patients had a lifetime diagnosis of MD. The correlation between the ages at onset of MD and dementia was calculated. The incidence of MD in AD patients in several 5-year-intervals before and after the onset of AD was compared with the average incidence of MD in the present AD sample and with the expected incidence of MD in the general population. No significant correlation between the onset of AD and of MD could be found after controlling for age, gender and the Mini-Mental-State. However, the incidence of MD 5 years before and after the onset of AD significantly exceeded the expected incidences-MD is only partially related to AD. However, the increased incidence of MD within 5 years before and after the onset of dementia may indicate that a common neurobiological process causes cognitive decline and depression in a subsample of AD patients.  相似文献   
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BACKGROUND: The long-term observation of vegetarians in affluent countries can provide insight into the relative effects of a vegetarian diet and lifestyle factors on mortality. METHODS: A cohort study of vegetarians and health-conscious persons in Germany was followed-up prospectively for 21 years, including 1,225 vegetarians and 679 health-conscious nonvegetarians. Standardized mortality ratios compared with the German general population were calculated for all causes and specific causes. Within the cohort, Poisson regression modeling was used to investigate the joint effects of several risk factors on overall and cause-specific mortality. RESULTS: Standardized mortality ratios for all-cause mortality was significantly below 100: 59 [95% confidence interval (95% CI), 54-64], predominantly due to a deficit of deaths from circulatory diseases. Within the cohort, vegetarian compared with nonvegetarian diet had no effect on overall mortality [rate ratio (RR), 1.10; 95% CI, 0.89-1.36], whereas moderate and high physical activity significantly reduced risk of death (RR, 0.62, 0.64), adjusted for age, sex, smoking, alcohol intake, body mass index, and educational level. Vegetarian diet was however associated with a reduced RR of 0.70 (95% CI, 0.41-1.18) for ischemic heart disease, which could partly be related to avoidance of meat. CONCLUSIONS: Both vegetarians and nonvegetarian health-conscious persons in this study have reduced mortality compared with the general population. Within the study, low prevalence of smoking and moderate or high level of physical activity but not strictly vegetarian diet was associated with reduced overall mortality. The nonsignificant reduction in mortality from ischemic heart diseases in vegetarians compared with health-conscious persons could be explained in part by avoidance of meat intake.  相似文献   
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Prenatal sonographic features of the rare anomaly of complete duplication of the urinary bladder and urethra are described in this case report. A coronal scan of the fetal pelvis at 29 weeks of gestation revealed two pyriform cystic structures. The umbilical arteries coursed around both of them. They emptied independently of each other. Postnatally the newborn had two vulvae, two anal openings, two bladders and two uteri.  相似文献   
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Muscle biopsies from the apex of both sides of the curve of 31 patients with idiopathic scoliosis showed abnormalities in fiber-type distribution in 68 per cent and in fiber size in 55 per cent. There was no preference for either side. Type 1 fiber predominance was as common as type 1 fiber deficiency. Atrophy occurred in 33 per cent and affected mainly type 1 fibers: atrophy of type 2 fibers was rare. Hypertrophy was limited to type 2 fibers, and occurred in 26 per cent. The strength factor for type 1 fibers exceeded that for type 2. Type 2A fibers were no larger than 2B fibers: there was a large type 2A predominance, more so on the convex side. Most of the muscle changes appear to be secondary and compensatory: none suggests a pathogenesis for the curve.  相似文献   
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