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1.
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   
2.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
3.
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   
7.
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   
8.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
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9.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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10.
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