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In an attempt to define the hemodynamic and radiographic parameters of normal erectile function 6 patients 20 to 41 years old (mean age 30.3 years) with erectile dysfunction that spontaneously resolved after a comprehensive evaluation were reviewed. The results included normal hormonal assays, normal penile biothesiometry and normal penile brachial index. The sleep tumescence and rigidity tracings were abnormal according to the criteria that sleep erections occur every 90 minutes, are associated with penile rigidity of greater than 550 gm. plus an increase in penile circumference of greater than 1.5 cm. and last longer than 15 minutes. High resolution ultrasonography, pulse wave Doppler ultrasound, dynamic pharmacocavernosometry and dynamic cavernosography were performed. After testing the patients were informed that no organic abnormalities had been detected. No medical or surgical treatment was given. The hemodynamic values are presented as suggested normal parameters: maintenance rate (mean 11 +/- 3 cc per minute), initial decompression rate (mean 59 +/- 17 mm. Hg/30 seconds) and radiographic findings (visualization of the cavernous, external pudendal and deep dorsal veins during pharmacocavernosography, performed at intracorporeal pressures of 100 mm. Hg). All 6 patients had maintenance rates of greater than 5 cc per minute. Of these 6 patients 5 had initial decompression rates of greater than 48 mm. Hg/30 seconds and 4 had 5-minute, post-infusion steady state values of less than 50 mm. Hg, criteria that have been used to define corporovenous dysfunction.  相似文献   
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In evaluating hypertensive children and adolescents, the etiological considerations should include a set of inherited disorders that share very low plasma renin activity (PRA) as a common feature. In particular among these disorders, glucocorticoid remediable aldosteronism (GRA) appears to be emerging as an important etiology of hypertension in the pediatric population. We report the evaluation of a 9-year-old Caucasian girl who presented with severe hypertension and a strong family history of early-onset hypertension. Her suppressed PRA, her family history, and her failure to respond to conventional antihypertensive therapy raised GRA as a potential etiology. The diagnosis was confirmed by an elevated ratio of urinary 18-oxotetrahydrocortisol to urinary tetrahydroaldosterone and genetic testing, which demonstrated the chimeric gene duplication. The molecular pathogenesis of GRA and the clinical implications are reviewed. Received May 15, 1996; received in revised form and accepted September 16, 1996  相似文献   
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To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.  相似文献   
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A retrospective review of post-delivery antibody records was performed at a teaching hospital and a community hospital to determine the frequency of new red cell alloantibody production and transfusion during pregnancy. If alloantibody was undetected at delivery, it was assumed that alloimmunization had not occurred. When antibody was detected, a chart review was performed to determine if the antibody was present at the beginning of the pregnancy or was newly produced during the pregnancy. A total of 17,568 pregnancies were reviewed. Antibody was detected at delivery in 948 (5.4%) cases, of which 89.5 percent (848/948) involved passive anti-D or clinically insignificant antibodies. The remaining 100 pregnancies involved clinically significant IgG antibodies. In 58 pregnancies, the antibody was detected in the first trimester, and in 42, new antibody production occurred during the pregnancy. Thus, the prevalence of new antibody production during pregnancy was 0.24 percent (95% confidence interval [CI], 0.17-0.32). Transfusion records indicated that the prevalence of transfusions during pregnancy was 0.09 percent (95% CI, 0.04-0.14). None of the women with new alloantibody formation during their pregnancies required transfusion; hence, new alloantibody production and the need for transfusion appear to be independent events. The probability of these events occurring together was 2.1 × 10(-6), or 1 in 500,000 deliveries.  相似文献   
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Impact of education for physicians on patient outcomes   总被引:4,自引:0,他引:4  
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To determine whether the previously described abnormalities in adrenal secretion and renal blood flow in essential hypertension are associated, we examined the responses to the relevant systems in 18 patients with essential hypertension. Young patients, under 30 years of age, were studied to minimize the likelihood that the phenomena were secondary to long-standing hypertension. To achieve a wide span of sodium balance, studies were performed during a high (200 mEq) sodium intake, a restricted (10 mEq) sodium intake and a restricted sodium intake supplemented by a further short-term diuretic-induced volume deficit (furosemide, 180 to 300 mg, to reduce body weight by 1 to 1.5 kg). The indexes measured included cardiac output (indocyanine green indicator dilution), plasma volume (125I albumin space), renal blood flow (radioxenon transit), plasma renin activity and aldosterone levels and aldosterone secretory rate. All of these variables, with the exception of Mood pressure and total peripheral resistance, were within the normal range during the two diets. However, the aldosterone secretory response to diureticinduced volume depletion on a low-sodium diet was clearly blunted in nine subjects. These nine subjects (abnormal responders) had a virtually absent aldosterone increment (23 ± 34 μg per 24 hours) compared with the normal responders (502 ± 70 μg per 24 hours). In addition, renal blood flow was significantly higher in these same nine subjects during both a high sodium intake (434 ± 19 versus 342 ± 26 ml/100 g per minute) and a restricted sodium intake (446 ± 11 versus 285 ± 39 ml/100 g per minute). Yet, there were no significant differences between these two groups in sodium or potassium balance, blood pressure, plasma volume, cardiac index or plasma renin activity during a high or low sodium intake. Normally, control of both aldosterone release by the adrenal and renal perfusion is dominated by angiotensin; an apparently blunted response of both systems suggests that there may be a generalized abnormality in the way angiotensin interacts with its target tissues in many young patients with essential hypertension.  相似文献   
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Context: A broad spectrum of GnRH-deficient phenotypes has been identified in individuals with both mono- and biallelic GNRHR mutations. Objective: The objective of the study was to determine the correlation between the severity of the reproductive phenotype(s) and the number and functional severity of rare sequence variants in GNRHR. Subjects: Eight hundred sixty-three probands with different forms of GnRH deficiency, 46 family members and 422 controls were screened for GNRHR mutations. The 70 subjects (32 patients and 38 family members) harboring mutations were divided into four groups (G1-G4) based on the functional severity of the mutations (complete or partial loss of function) and the number of affected alleles (monoallelic or biallelic) with mutations, and these classes were mapped on their clinical phenotypes. Results: The prevalence of heterozygous rare sequence variants in GNRHR was significantly higher in probands vs. controls (P < 0.01). Among the G1-G3 groups (homozygous subjects with successively decreasing severity and number of mutations), the hypogonadotropic phenotype related to their genetic load. In contrast, subjects in G4, with only monoallelic mutations, demonstrated a greater diversity of clinical phenotypes. Conclusions: In patients with GnRH deficiency and biallelic mutations in GNRHR, genetic burden defined by severity and dose is associated with clinical phenotype. In contrast, for patients with monoallelic GNRHR mutations this correlation does not hold. Taken together, these data indicate that as-yet-unidentified genetic and/or environmental factors may combine with singly mutated GNRHR alleles to produce reproductive phenotypes.  相似文献   
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