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991.
The arrhythmia generating dysplasia of the right ventricle is a congenital anomaly suggesting a hereditary substratum. It usually manifests itself as follows: a young patient, with recurrent episodes of ventricular tachycardiac. There is no "pathognomonic sign" of dysplasia. The latter may only be determined by anatomical examination of the heart, macroscopically as well as microscopically. The most difficult differential diagnosis concerns minor or localized forms of dilated idiopathic myocardiopathy or sequelae of myocarditis with ventricular tachycardia originating in the right ventricle. It seems, currently, more appropriate to talk about "arrhythmia generating syndrome of the right ventricle" rather than arrhythmia generating dysplasia of the right ventricle, in these particular cases. The arrhythmia generating syndrome of the right ventricle could cause a sudden death in these young patients, especially during a violent physical exercise or practise of sports. The current nosological classification is based on an experience acquired by comparing a few isolated cases. The search for late potentials by summation-mean measurements and nuclear magnetic resonance could provide a new diagnostic approach.  相似文献   
992.
BACKGROUND: We previously demonstrated that short-cycle structured intermittent therapy (SIT; 7 days without therapy followed by 7 days with antiretroviral therapy [ART]) with a ritonavir-boosted, indinavir-based, twice-daily regimen maintained suppression of plasma HIV viremia while reducing serum levels of lipids. Adherence to such a regimen may be problematic for certain patients. METHODS: Eight patients with a history of receiving combination ART that maintained suppression of plasma HIV RNA to <50 copies/mL received a once-daily SIT regimen of didanosine, lamivudine, and efavirenz. RESULTS: For 7 patients, suppression of plasma HIV RNA to <50 copies/mL was maintained for 60-84 weeks. Four patients with adequate samples had no evidence for an increase in plasma viremia for up to 72 weeks, by use of an assay with a limit of detection of <1 copy/mL. The lack of rebound viremia may be the result of the persistence of efavirenz in plasma on day 7 of the no-therapy period, as was detected in 7 of 7 patients. There was no significant change in CD4(+) T cell counts or serum hepatic transaminase or lipid levels. CONCLUSION: A once-daily short-cycle SIT regimen maintained suppression of plasma HIV RNA while preserving CD4(+) T cell counts. Such a regimen may have importance in resource-limited settings where the monetary cost of continuous ART is prohibitive.  相似文献   
993.
We studied the dynamics of CD4 cell counts after the interruption of virologically successful highly active antiretroviral therapy (HAART) in 139 patients. Changes in CD4 cell counts during HAART interruption followed a biphasic pattern: an initial rapid decline during the first month followed by a slow decrease. During 48 weeks of follow-up mean CD4 cell counts remained just above the mean pre-HAART level. This limits the feasibility of structured treatment interruptions for patients with low nadir CD4 cell counts.  相似文献   
994.
A 47 year old patient underwent endocavitary electrophysiological investigation for recurrent syncopal episodes occuring three years after an inaugural enterior myocardial infarction. Syncopal ventricular tachycardia was induced during the investigation when the bipolar catheter was in contact with the Bundle of His and several external electric shocks were required for its reduction. During cardioversion a complete intra-hisian atrio venticular block was observed and remained permanently although the values of the conduction intervals had previously been normal. This complication of defibrillation is thought to be the result of an induction phenomenon.  相似文献   
995.
Corrected QT intervals were determined in 13 patients with severe, chronic hypercalcemia. The QOTC interval was short in only 2 of 14 instances; QATC in 5 of 15 instances, and QETC in 5 of 16 instances. The correlations between serum calcium and the QTC measurement were not significant when evaluating either linear or curvilinear (quadratic) relationships. Small and inconsistent changes were found when comparing the QT intervals before the development of the hypercalcemic episode, during hypercalcemia, or after successful treatment. We conclude that shortening of the QT interval is an unreliable index of clinical (chronic) hypercalcemia.  相似文献   
996.
INTRODUCTION AND OBJECTIVES: This cross-sectional study examined the overall clinical characteristics and management of 1252 outpatients with heart failure in 3 countries (Spain, France and Germany). MATERIAL AND METHOD: A standardized questionnaire was used to record demographic, diagnostic, clinical and treatment data for all patients seen on one day (26 April 2001) by 465 outpatient cardiologists. RESULTS: Men accounted for 62.1% of the patients in the population, and mean age of the patients was 68.3 years. In the twelve months prior to the study 78% of the patients consulted their physician at least once because of heart failure, and 36.2% had hospital admissions. Differences between the three countries were observed in reported causes of heart failure (alone or in combination) such as ischemic heart disease (France 40.7%, Germany 41.3%, Spain 26%, P<.0001) and hypertension (France 10.7%, Germany 16.7%, Spain 43.6%, P<.0001). How-ever the proportion of patients with prior myocardial infarction was very similar (France 63.7%, Germany 69.5%, Spain 65%, P=NS). Diuretics were not prescribed in 19.7% of the patients, ACE inhibitors were not prescribed in 27.9%, and beta blockers were not prescribed in 52.3%. CONCLUSIONS: The study provides further information on the consumption of large amounts of medical resources because of heart failure. The reported etiologies differed between countries. However, the proportion of patients with prior myocardial infarction was very similar. Treatment with ACE inhibitors and beta blockers was slightly more common than previously reported, although beta blockers continue to be underused.  相似文献   
997.
Cushing's syndrome due to nodular adrenal hyperplasia comprises a clinically and biochemically heterogeneous group of disorders whose pathogenesis is unclear. We describe two patients with atypical steroid dynamics and large unilateral adrenal nodules who had pituitary ACTH-dependent disease. In the differential diagnosis of Cushing's syndrome, we recommend repeated ACTH measurement and selective venous sampling—particularly in those patients with impaired dexamethasone suppressibility and abnormal findings on computerized tomography.  相似文献   
998.
With the recent availability of biosynthetic human proinsulin there has been a renewed interest in evaluating its metabolic effects, either alone or in combination with insulin. It has been suggested that pretreatment with proinsulin enhances the hypoglycemic response to subsequently administered insulin. On the other hand, the simultaneous administration of proinsulin and insulin has additive, not synergistic, effects. To clarify this question we used the euglycemic glucose clamp technique in 10 normal subjects to compare the steady state effects on glucose disposal of combined infusions of insulin (0.54 microgram/M2 . min, equivalent to 15 mU/M2 . min) and proinsulin (2.75 micrograms/M2 . min) given both simultaneously and sequentially. The mean +/- SEM steady state glucose disposal rates were similar whether the two hormones were given simultaneously (7.2 +/- 0.7 mg/min . kg), after proinsulin pretreatment (7.7 +/- 0.7 mg/min . kg), or after insulin pretreatment (7.1 +/- 0.7 mg/min . kg). The serum proinsulin concentration of 5.39 +/- 0.3 pmol/ml during the infusion of proinsulin alone was unchanged by the simultaneous infusion of insulin, suggesting that in the doses used, insulin did not affect proinsulin clearance. We conclude that in normal subjects there is no enhancement of the combined action of insulin and proinsulin to stimulate glucose disposal by pretreatment with proinsulin or insulin.  相似文献   
999.
AIM: To assess the extent and reasons of noncompliance in surveillance for patients undergoing polypectomy of large (≥ 1 cm) colorectal adenomas.METHODS: Between 1995 and 2002, colorectal adenomas ≥ 1 cm were diagnosed in 210 patients and subsequently documented at the Erlangen Registry of Colorectal Polyps. One hundred and fifty-eight patients (75.2%) could be contacted by telephone and agreed to be interviewed. Additionally, records were obtained from the treating physicians.RESULTS: Fifty-four out of 158 patients (34.2%)neglected any surveillance. Reasons for non-compliance included lack of knowledge concerning surveillance intervals (45.8%), no symptoms (29.2%), fear of examination (18.8%) or old age/severe illness (6.3%).In a multivariate analysis, the factors including female gender (P = 0.036) and age ≥ 62 years (P = 0.016)proved to be significantly associated with non-compliance in surveillance.CONCLUSION: Efforts to increase compliance in surveillance are of utmost importance, This applies particularly to women's compliance. Effective strategies for avoiding metachronous colorectal adenoma and cancer should focus on both the improvement in awareness and knowledge of patients and information about physicians for surveillance.  相似文献   
1000.
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