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991.
W Knopp  G Muhr  J Rehn 《Der Unfallchirurg》1989,92(12):577-583
Post-traumatic axial malalignment of the lower limbs causes osteoarthrosis of the adjacent joints. Whether or not correction osteotomy is indicated depends upon the degree and the location of the deformity. Malalignment of the proximal femur should be corrected if the axis of the leg does not pass through the knee joint. If the axis is outside the central half of the tibial head, the indication for correction osteotomy is a relative one: varus deformities are more difficult to compensate and it is more urgent that these be corrected. Of 103 patients who underwent osteotomies of the proximal femur during the period 1973-1981, there were 73 in whom it was possible to follow up an average of 7 years after the realignment procedure. In nearly two-thirds of these patients the clinical symptoms noted before surgery had improved. In 10 cases of pseudarthrosis of the femoral neck, necrosis of the femoral head could not be avoided in spite of the surgical correction; nonetheless, the prognosis is better if the correction is done within the first 3 months after the trauma.  相似文献   
992.
The N-hydroxylation of carcinogenic arylamines represents an initial step in their metabolic activation. Animal studies have shown that this reaction is catalyzed by the cytochrome P450 (P450) enzymes P450 1A1 and P450 1A2. In this study, utilizing enzymes expressed in Escherichia coli (and purified) or in human B-lymphoblastoid cells, the catalytic activities of recombinant human P450 1A1, P450 1A2, and P450 3A4 for N- hydroxylation of several carcinogenic arylamines were determined. P450 1A2 from both expression systems catalyzed the N-hydroxylation of 4- aminobiphenyl and the heterocyclic amines, 2-amino-3-methylimidazo[4,5- f/quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Rates were similar, with values of 1.1-7.8 nmol/min/nmol P450. In contrast, P450 1A1 catalyzed N-hydroxylation of only PhIP, and no activity was observed with P450 3A4. Further kinetic analysis with purified P450 1A2 showed similar Km and Vmax values for N-hydroxylation of the arylamines. Furafylline and fluvoxamine, inhibitors of P450 1A2 activity in human liver microsomes, were found to be inhibitory of the recombinant P450 1A2 N-hydroxylation activity. Results from this study are supportive of a major role for human P450 1A2 in the metabolic activation of arylamines.   相似文献   
993.
994.
Cholangiograms from 104 patients (and serial cholangiograms in 66 patients) with primary sclerosing cholangitis (PSC) were reviewed. In 13 patients the additional diagnosis of cholangiocarcinoma was made at biopsy or autopsy. Cholangiograms from patients with both PSC and carcinoma were compared with cholangiograms from patients with PSC alone. Marked dilatation of ducts or ductal segments (100% vs. 24%) and the appearance of a polypoid mass (46% vs. 7%) were common findings in the group of patients whose disease was complicated by malignancy. In the malignant group, polypoid masses were larger, measuring 1 cm or greater in diameter. On serial cholangiograms, four of 15 patients with progressive stricture formation and four of five with progressive ductal dilatation proved to have carcinomas. The frequent occurrence of bile duct carcinoma as a complication of PSC in this group of patients indicates that PSC has a strong tendency to undergo malignant degeneration. Cholangiographic findings which suggest malignant degeneration include markedly dilated ducts or ductal segments, presence of a polypoid mass 1 cm or greater in diameter, and progressive stricture formation or ductal dilatation.  相似文献   
995.
996.
997.
This case demonstrates the myelographic, CT myelographic, and MR appearance of primary lymphoma of the cauda equina. It also illustrates the utility of high-resolution CT myelography in certain lesions of the cauda equina. The authors feel that CT myelography, with its inherent ability to depict individual nerve roots and therefore any pathologic involvement as well, should be considered an adjunct to MR in imaging the cauda equina.  相似文献   
998.
999.
吲满氨酯的磷光分析   总被引:2,自引:0,他引:2  
黄如衡 《药学学报》1993,28(2):140-145
吲满氨酯具有强的磷光,其水液激发波峰304 nm,发射波峰434 nm,磷光寿命为3.87s。在碱液中磷光比在酸液中强。重原子碘对吲满氨酯磷光有增强作用,而寿命变短。金属重原子Cu2+,Fe3+,Pb2+,Tl3+,Zn2+及钼酸铵等均无增强作用,Cu2+,Fe3+等反有猝灭作用。比较了9种吲满氨酯类似物的磷光性质,当2位亚甲基氧化为酮基后磷光明显下降。建立了吲满氨酯的磷光分析法,最小检出量为5ng。小鼠腹腔注入药物0.1 mg/kg后10 min其血药浓度为149 ng/ml。  相似文献   
1000.
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