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91.
In twelve patients with acute renal failure, mean plasma levels of atrial natriuretic factor (ANF) and of its second messenger cGMP were found elevated at the early phase of the disease, but tended to return towards normal values at recovery. Variations of plasma ANF and cGMP were correlated significantly (p less than 0.05) with those of total blood volume. At the early phase of the disease, plasma ANF was also correlated with the excreted fraction of filtered sodium (FENa) (r = 0.95). Moreover, plasma ANF and FENa peaked concomitantly at the onset of the diuretic phase in the five patients who were not treated by diuretics or dialysis and were studied sequentially during the course of the disease. It is suggested that enhanced plasma ANF levels might reflect one of the mechanisms of adaptation controlling body fluid balance in acute renal failure.  相似文献   
92.
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed.  相似文献   
93.
Venous clots: evaluation with MR imaging   总被引:2,自引:0,他引:2  
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi.  相似文献   
94.
Plasma atrial natriuretic factor (ANF), plasma cyclic guanosine monophosphate (cGMP), plasma aldosterone, plasma-renin activity (PRA) and hemodynamic parameters were measured in heart-transplant recipients and control patients (chest pain syndrome) during right-sided heart catheterization under basal conditions and in response to an intravenous saline load. Basal plasma ANF and cGMP were higher in heart-transplant recipients than in control patients, whereas PRA and plasma aldosterone did not differ. The high plasma ANF levels in heart-transplant recipients did not result from high atrial pressures but appeared to be related with elevated atrial dimensions and cyclosporine-induced renal failure. During volume expansion, plasma ANF increased in control patients and remained elevated during the postinfusion period. In heart-transplant recipients, the changes in plasma ANF were less marked despite identical increases of atrial pressures. The sluggish response of plasma ANF in this group was associated in the postinfusion period with a nonreturn of the hemodynamic parameters to their basal values in contrast with what was observed in control patients.  相似文献   
95.
96.
High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.  相似文献   
97.
98.
本文报道了以1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-羧酸,用混合酸酐法与7-ACA,7-ADCA,7-ACT和7-ACD缩合,合成了24个1,7-双取代-1,4-二氢-4-酮-1,8-萘啶-3-甲酰胺头孢菌素衍生物,通过葡聚糖凝胶(Sephadex LH-20)及离心薄层层析纯化精制,得到纯品。体外抑菌试验结果表明:大多数新头孢菌素衍生物对革兰氏阳性菌具有较好的抗菌作用。尚有一些新头孢菌素衍生物对某些革兰氏阴性菌具有中等敏感程度。  相似文献   
99.
100.
DiSantis  DJ; Cramer  MS; Scatarige  JC 《Radiology》1987,164(2):363-364
To test the feasibility of teleradiology for use with excretory urograms obtained in the emergency department in cases for suspected renal colic, radiographs from 43 patients were digitized, transmitted via standard phone lines, and viewed on a video monitor 2 miles distant. Diagnostic interpretations of the video image and the original radiograph were reviewed for degree of concordance. The video and film images of the 27 examinations showing obstruction were interpreted with 100% correlation. Agreement as to the site of obstruction was present in 93% of cases. Only two-thirds of renal and ureteral calculi seen on the radiographs were discerned on the video images, however. Teleradiology proved as useful for ongoing monitoring and modification of these examinations as for initial interpretation.  相似文献   
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