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von Hippel-Lindau disease affecting 43 members of a single kindred   总被引:22,自引:0,他引:22  
We present a 6-generation kindred of over 221 members, 43 of whom were affected with von Hippel-Lindau (vHL) disease. Through a simple screening protocol, we diagnosed vHL retrospectively in 15 cases, and for the first time in 28, 11 of whom were presymptomatic. We found many complications of vHL in previously diagnosed relatives and in new cases. This study has demonstrated the utility and benefit of preventive surveillance in those known to have vHL, and of presymptomatic screening for affected relatives in families with vHL. The features of vHL were reviewed in our 43 cases and 511 cases from the medical literature. The patterns, frequencies, and ages of onset for each lesion were compared. Renal malignancies caused almost as much mortality in vHL as CNS malignancies. This family was exceptional for absence of pheochromocytoma and erythrocythemia, for more renal and pancreatic cysts and malignancies, and for slightly fewer eye or CNS lesions. Bilateral renal adenocarcinomata were found presymptomatically in five young subjects, who had bilateral nephrectomy and hemodialysis. Three survived long-term after renal transplants. Five relatives had pancreatic malignancies, which are definite although uncommon manifestations of vHL. Recommendations are made for family screening, which was economical and effective. Bayesian calculations help to predict risks for genetic counseling. The molecular basis of vHL may soon be found, since it has been linked to DNA markers on the short arm of chromosome 3.  相似文献   
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The purpose of this study is to show the spectrum of adjacent organ invasion and to make a brief review of hepatic alveolar hydatid disease (AHD), using CT and MR imaging. We retrospectively reviewed CT and MR images of three patients with various adjacent organ invasions surgically and histologically proven to be AHD. Local invasion to right kidney and adrenal, right hemidiaphragm and lung were detected in one patient, right adrenal in another patient and gall bladder, duodenum, gastric wall and pancreas invasion in the other. AHD may rarely extend to the gall bladder, stomach, duodenum, pancreas, right adrenal and kidney, diaphragm, pleura and lung. The extension of the disease outside the liver is usually encountered in patients with large, peripherally located masses in the advanced stage of the disease.  相似文献   
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We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.  相似文献   
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Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care.  相似文献   
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1. Changes in the release of nitric oxide (NO) in vivo were studied in rats following the administration of endothelium-dependent and -independent vasodilators as well as the NO synthesis inhibitor, NG-nitro-L-arginine methyl ester (L-NAME). NO production was assessed by measuring variations of nitrate in plasma by capillary ion analysis. 2. Intravenous administration of the endothelium-dependent vasodilators, bradykinin (2 and 10 micrograms kg-1 min-1) or substance P (0.3-3 micrograms kg-1 min-1) caused a transient dose-dependent hypotension followed by an increase in plasma nitrate concentration (maximal increments: 33 +/- 5% and 38 +/- 6%, for bradykinin and substance P, respectively). Prior administration of L-NAME (10 mg kg-1 min-1) inhibited the hypotension and increase in plasma nitrate caused by these substances. Intravenous administration of sodium nitrate (200 micrograms kg-1) also produced a transitory elevation in plasma nitrate which was similar in magnitude as that caused by the vasodilators. A rapid and transitory increment in plasma nitrate was observed after i.v. administration of authentic NO (400 micrograms kg-1). 3. Rats receiving the endothelium-dependent vasodilators, prostacyclin (0.6 micrograms kg-1 min-1) or adenosine (3 mg kg-1 min-1) intravenously showed a drop in blood pressure paralleled by a decrease in plasma nitrate (maximal decreases: 34 +/- 5% and 24 +/- 4%, for prostacyclin and adenosine, respectively). A similar effect on the plasmatic concentration of nitrate was observed when L-NAME (10 mg kg-1 min-1, i.v.) was administered to the animals. 4. This study demonstrates that (i) changes in plasma nitrate can be detected in vivo after stimulation or inhibition of NO synthase, (ii) an increased production of NO, measured as plasma nitrate, is related to the hypotension caused by bradykinin and substance P and (iii) a diminished concentration of plasmatic nitrate is associated to the hypotension induced by adenosine or prostacyclin (endothelium-independent vasodilators), suggesting that the L-arginine: NO pathway is capable of rapid down-regulation in response to a fall in blood pressure.  相似文献   
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Body composition measured with isotopic dilution was compared with anthropometric measurements. The study was carried out in 47 subjects from both sexes, 65 to 92 years old. Total body water (TBW), anthropometric measurements, and dynamometry were assessed. TBW was significatively higher in men than women and decreased with age. Dynamometry and fatfree mass were well correlated (r=0.73 in males and r=0.58 in females) and significantly different between sexes. A negative correlation was found for dynamometry with age, being significant for women. Linear regression equations to predict TBW from anthropometric measurements in males and females were obtained: Males: TBW(I)=19.349+0.617 weight(kg) — 0.931 mid-arm circumference(cm)+0.122 dynamometry (kg) Females: TBW(l)=−5.531+0.343 weight(kg)-0.213 triceps skinfold (mm)+ 0.148 dynamometry(kg) + 3.424 wrist diameter (cm). This simple model is proposed for use in epidemiological and field studies where other more sophisticated methods can not be applied.  相似文献   
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Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth.  相似文献   
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