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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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Bottomley  PA; Lee  Y; Weiss  RG 《Radiology》1997,204(2):403
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
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卢日刚 《药学学报》1992,27(11):871-874
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).  相似文献   
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An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres.  相似文献   
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