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991.
992.
A 38-year-old woman had diffuse, nonnodular, lepromatous leprosy and Lucio's phenomenon. Most cases of Lucio's phenomenon have been reported to have a leukocytoclastic vasculitis as the underlying pathologic abnormality. In this patient, however, the histologic picture of an early lesion of Lucio's phenomenon showed a milk, mononuclear cell infiltration, endothelial swelling, vascular thrombosis, and ischemic necrosis. Lepra bacilli were abundant around nerves and blood vessels, and many were noted in vascular walls and endothelium. Our findings raise the possibility that some cases of Lucio's phenomenon may be caused by vascular damage due to direct invasion of Mycobacterium leprae and not necessarily by leukocytoclastic vasculitis. 相似文献
993.
994.
Plasma prostaglandin F (PGF) was measured by a radioimmunoassay method in 24 subjects with tumours of the female genital tract. Levels in the tumour group ranged from 25 pg/ml to 134 pg/ml and were almost all greater than the values observed in a control group of 41 healthy women who had a mean (+/-SD) level of 21 (+/-3.4)pg/ml. There was a relationship between plasma PGF levels and the stage of the disease. Patients with resectable tumours showed a fall in PGF levels postoperatively and those with disseminated malignancy demonstrated increasing levels as the disease progressed. Plasma PGF may provide a clinical prognostic marker in the management of patients with malignant tumours. 相似文献
995.
Phenylalanine ammonia-lyase. Induction and purification from yeast and clearance in mammals 总被引:1,自引:0,他引:1
Yeast phenylalanine ammonia-lyase (EC 4.3.1.5) catalyzes the deamination of L-phenylalanine to form trans-cinnamic acid and tyrosine to trans-coumaric acid. Maximal enzyme activity in Rhodotorula glutinis (2 units/g, wet weight, of yeast) was induced in late-log phase (12 to 14 hours) of growth in a culture medium containing 1.0% malt extract, 0.1% yeast extract, and 0.1% L-phenylalanine. A highly purified enzyme was obtained by fractionation with ammonium sulfate and sodium citrate followed by chromatography on DEAE-cellulose and Sephadex G-200. The active preparation yielded a major component on three different polyacrylamide gel electrophoretic systems. Antisera to phenylalanine ammonia-lyase was raised in rabbits and detected by double immunodiffusion. The antigen-antibody complex was enzymatically active in vitro. The biological half-life of the enzyme was approximately 21 hours in several mammalian species (mice without and with BW10232 adenocarcinoma and B16 melanoma, rats, and monkeys) after a single injection; however, upon repeated administration, phenylalanine ammonia-lyase had a much shorter biological half-life. The onset of rapid clearance occurred earlier in tumor-bearing than in nontumor-bearing mice indicating a direct or indirect influence by the tumor on the biological half-life of phenylalanine ammonia-lyase. 相似文献
996.
997.
Urodynamic evaluation of urethral sphincter efficiency can be carried out by constant carbon dioxide perfusion, constant water perfusion, or the use of membrane catheters. A comparison of these three techniques was made in in vitro and in vivo experiments. Results, and advantages and disadvantages of each method are discussed. From all factors considered in this study--responsiveness to pressure changes sensitivity to pressures at various levels along the urethra, and reproducibility and accuracy of the profile--the membrane catheter system was by far superior to either of the flow systems. 相似文献
998.
999.
1000.
HF Becker AJ Piper WE Flynn SG McNamara RR Grunstein JH Peter CE Sullivan 《Canadian Metallurgical Quarterly》1999,159(1):112-118
BACKGROUND: The global DNA methylation of 136 breast lesions (117 primary invasive carcinomas, 5 benign phyllodes tumors, 11 fibroadenomas, and 3 sclerosing adenosis) and their respective adjacent parenchyma was analyzed using an in vitro enzyme assay. METHODS: In the group of patients with breast carcinoma, DNA hypomethylation was correlated with clinical and pathologic parameters known to affect disease prognosis. Histopathologic type, disease stage, and tumor grade were evaluated according to the World Health Organization classification, the TNM system, and the criteria of Elston and Ellis' criteria, respectively. DNA flow cytometry was performed in fresh/frozen samples stained with propidium iodide. Hormone receptor (estrogen and progesterone receptor) status was determined by immunocytochemistry. RESULTS: The comparative study of DNA methylation showed that the DNA of breast carcinomas was statistically significantly less methylated than the DNA of the respective adjacent parenchyma (P=0.0001), the DNA of breast benign lesions (P=0.0002), and the DNA of normal parenchyma (P < 0.0001). A statistically significant correlation was found between the global DNA hypomethylation and the disease stage (P=0.0009), tumor size (P=0.0026), and histologic grade (P=0.0097) of malignant neoplasms. A trend for DNA from breast carcinomas with positive axillary lymph nodes (N1) to be more hypomethylated than those without nodal involvement (NO) (P=0.055) was verified. In contrast, no significant association was found between DNA methylation and histologic type of tumors, hormone receptors, DNA ploidy, and S-phase fraction. CONCLUSIONS: The current shows that DNA hypomethylation is increased in breast carcinomas, playing a potentially important role in tumor development. These findings also suggest that DNA methylation status may be a biologic marker with prognostic significance in this group of neoplasms. 相似文献