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991.
Cytokines play a part in the control of cellular growth, differentiation and development. Given such pleiotropic activities, it is not unexpected that the expression of the cytokines is tightly regulated. When cytokine-mediated processes are altered by mutation and/or overexpression of some cytokine or cytokine receptor genes, oncogenic transformation can occur. Oncogenes which derive their transforming potential through this mechanism include sis, which represents the activated form of the platelet-derived growth factor B chain, hst1/K-fgflint-2, which share appreciable homology with the gene family of fibroblast growth factors, fms, which is related to the cell surface receptor for macrophage-colony stimulating factor, and erbB-1, which encodes a truncated form of the epidermal growth factor receptor. Cytokine treatment has resulted in modulation of aberrant oncogene activity in some model systems.  相似文献   
992.
993.
Background: t(14; 18)/bcl-2 gene rearrangement (R) is claimedto impart a worse rate of complete remission and disease-freesurvival in diffuse large cell lymphoma (DLCL). DEL 6q has alsobeen associated with poor outcome. Design: Retrospective studyof 54 patients with either diffuse large cell or immunoblasticlymphoma who had cytogenetics and/or molecular studies performed.Results: Patient characteristics, complete remission rate, andtime to treatment failure (TTF) were similar at three year follow-upfor groups with and without t(14; 18)/BCL-2R Survival was worsefor the former but the difference was not statistically significant.For DEL 6q, patient characteristics and survival rates weresimilar at three year follow-up for patients with and withoutthe abnormality. TTF was worse for the former but this was notstatistically significant. Conclusion: This study, with equalor greater number of patients with t(14; 18) than previous reports,fails to show a worse prognosis for patients with the t(14;18) chromosomal abnormality. A definite association will awaitfurther accrual of patients and a meaningul multivariate analysis. lymphoma, BCL-2, cytogenetics, DEL 6q  相似文献   
994.
The prevalence of heavy alcohol consumption is a major problem of increasing proportions throughout the world. Although alcohol sensitizing drugs and more recently serotonin uptake inhibitors are drug interventions with some following, their long term beneficial consequences have yet to be demonstrated. In recent years, we have demonstrated that manipulating activity in the renin-angiotensin system will dramatically alter voluntary alcohol consumption in rats. Based on these findings, the present study evaluated the ability of a class of drugs known as the angiotensin converting enzyme inhibitors to reduce voluntary alcohol drinking in laboratory animals. These drugs prevent the conversion of angiotensin I to angiotensin II. They have been licensed for use in Europe and North America and are indicated in the treatment of hypertension. Our experiments showed that both captopril (Capoten, Squibb) and enalapril (Vasotec, Merck Sharpe & Dohme) can reduce alcohol drinking in both normotensive and hypertensive animals regardless of whether the pattern of intake is in a bout or of a less exaggerated nature. Furthermore, this change in alcohol intake can occur without concomitant changes in blood pressure, plasma renin activity, overall fluid balance, or the distribution and metabolism of alcohol. Taken together these findings suggest that the angiotensin converting enzyme inhibitors should be evaluated in a clinical setting for they may prove to be a useful new treatment or treatment adjunct for alcohol abuse in humans.  相似文献   
995.
996.
It has long been noted that tetanus is rare in leprosy patients. Five cases of tetanus are reported in leprosy patients in Addis Ababa, Ethiopia. Although natural immunity to tetanus occurs and this appears to be higher in leprosy patients than in the general population, it is not completely protective. Further research on the relationship between tetanus and leprosy is indicated. Although firm epidemiologic data are lacking, it is prudent to give leprosy patients at least one dose of tetanus toxoid.  相似文献   
997.
V Frecer  S Miertus 《Neoplasma》1988,35(5):525-538
A mechanistic QSAR study on N-nitrosamines (NA) was performed with the aid of the semiempirical MINDO/3 method. Both the chemical reactivity and the transport in biological medium were taken into account. The parent NA molecules and their first reaction intermediates in the metabolic activation pathway were examined for possible determinants of the relative carcinogenic potency. The correlations found support the previous suggestions concerning the metabolic C alpha radical hydroxylation of NA. The role of transport properties in the early stage of NA biotransformation was also demonstrated.  相似文献   
998.
Using indirect immunohistochemistry and an antiserum raised against rat corticotrophin-releasing factor (CRF) we have outlined an asymmetric network of cells and varicose fibers in sheep adrenal cortex. This network was not associated with the larger splanchnic nerves, but was occasionally found in small bundles or with blood vessels; in most instances fibers were found weaving independently through cortical parenchyma. A plexus of fibers was found in the zona reticularis, with a few fibers ramifying into adjacent medulla. Uni or bipolar cells were found throughout the cortex, with the greatest frequency at the corticomedullary junction; a multipolar-type cell was also found in this area. Staining of varicose structures and most cells was abolished by incubation with excess rat CRF 1-41, but not by ovine CRF or a range of other peptides. Though the immunoreactive species has not as yet been identified, it may thus share homology with sequences present in rat but not ovine CRF.  相似文献   
999.
1000.
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