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Steinberg HV; Nelson RC; Murphy FB; Chezmar JL; Baumgartner BR; Delaney VB; Whelchel JD; Bernardino ME 《Radiology》1987,162(2):337-342
A prospective study compared the efficacy of Doppler ultrasonography (US) and magnetic resonance (MR) imaging in evaluating 38 renal allografts, with specific attention to transplant rejection. Forty-three Doppler US and 42 MR examinations were performed and interpreted. Histologic correlation was obtained from 22 biopsy or nephrectomy specimens. Clinical correlation or a response to instituted therapy was used as confirmation in the remaining allografts. Accuracy in identifying cyclosporine toxicity or acute tubular necrosis could not be evaluated because there were few such cases, with concomitant rejection in most. The ability to predict and identify presence or absence of rejection was not affected by different serum creatinine values. Doppler US was significantly superior to MR imaging in identifying allograft rejection, demonstrating a higher sensitivity (95% vs. 70%), specificity (95% vs. 73%), and accuracy (95% vs. 71%). Because of its low cost and accessibility, Doppler US should become the primary modality for renal transplant screening. 相似文献
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We report the synthesis and in vitro studies as MAO-A and MAO-B inhibitors of a new series of 2-(5-methoxy-1-methylindolyl)alkylamines, including 2-(5-methoxy-1-methylindolyl)amine 9 and its N-methyl derivative 10, 1-[2-(5-methoxy-1-methylindolyl)]ethylamine 1 and its N-methyl derivative 2 and 3-[2-(5-methoxy-1-methylindolyl)propylamine 11 and its N-methyl derivative 12, so as some of the N-(2-propynyl), N-(2,3-butadienyl) and N-(2-butynyl) derivatives of 1, 2, 11 and 12 (compounds 3–8 and 13–18). All compounds were found to inhibit both MAO-A and MAO-B. Comparison with a previous series of 2-(5-methoxy-1-methylindolyl)methylamine derivatives (A1–A9) shows that in the new series, the inhibitory potency towards MAO-A generally decreases, whereas the inhibitory potency towards MAO-B generally increases, resulting in a loss of the selectivity for MAO-A seen in the reference compounds A1–A9. Structure-activity relationships are discussed. 相似文献
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Molecular heterogeneity of glucose-6-phosphate dehydrogenase A- 总被引:9,自引:0,他引:9
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is probably the most common disease-producing genetic polymorphism of humans. Virtually all G6PD-deficient Africans show the G6PD A- phenotype, an electrophoretically rapid, deficient enzyme. The recently acquired ability to identify the point mutations producing the different variants has given us new insights into the population genetics of G6PD variants. Twenty-nine males with the G6PD A- phenotype were studied. They were of African, Mexican, Spanish, and US white ethnic origin. All had the A---G transition at nucleotide 376 characteristic of G6PD A. In each case, one of three additional mutations was present, at nucleotides 202, 680, or 968. That in this population second mutations producing G6PD deficiency occurred only on the genetic background of G6PD A suggests that G6PD A was at one time the most common type of G6PD in Africa. However, the nucleotide sequence of the chimpanzee (Pan troglodytes) G6PD indicates that the primordial human type of G6PD was G6PD B. 相似文献
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Rotator cuff impingement syndrome: MR imaging 总被引:2,自引:0,他引:2
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Primary lesions of bone in the 1st decade of life: retrospective survey of biopsy results 总被引:1,自引:0,他引:1
Primary bone tumors in early childhood are uncommon, and the incidence of malignancy in the 1st decade of life has not been evaluated adequately in the literature. For this reason, we conducted a retrospective review of 268 biopsies of the bone in 249 patients who were less than 10 years of age. Benign tumors were found much more frequently than malignant lesions. Osteochondroma and histiocytosis X were the most common lesions. The incidence of several benign lesions in our series was deceptively low, as many lesions showed typical radiographic findings, precluding the need for biopsy or excision. Of 41 primary malignant bone tumors, Ewing sarcoma was slightly more common than osteosarcoma. The rib was the most frequent site of the former; the distal femur, of the latter. 相似文献