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991.
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993.
The chromosome pattern of leukemias induced by gamma-irradiation in the translocation T190/tf and in the genetically related tf/tf strain was analyzed. The degree of variation in chromosome numbers was similar in both experimental groups. Karyotypically, the tumors of both strains showed slight and less frequent higher degree of variability. The most consistent karyotypic change was trisomy of chromosome 15, whose frequency was similar in both strains. In one of the leukemias a marker chromosome derived by translocation involving chromosome 15 was identified. Comparison of the breakpoint in this translocation with literature data on other translocations of chromosome 15 found in leukemias enabled narrowing the region on chromosome 15 containing the postulated genes essential for murine leukemogenesis. The incidence of leukemias was lower in the T190/tf translocation strain than in the tf/tf strain with normal karyotype.  相似文献   
994.
995.
The mechanisms by which adreno-corticoid hormones regulate Na+,K(+)-ATPase in adult kidney were studied in adrenalectomized (Adx) rats. Five days after adrenalectomy, Na+,K(+)-ATPase activity was significantly reduced in the renal cortex homogenate (C = 13.0 +/- 0.8 vs. Adx = 7.1 +/- 0.7 mumol Pi mg-1 protein h-1) and in renal microsomes (C = 30.3 +/- 1.9 vs Adx = 14.6 +/- 1.3 mumol Pi mg-1 protein h-1). Glucocorticoid replacement treatment of adrenalectomized rats with betamethasone (20 micrograms kg-1 body wt twice daily for 5 days) effectively counteracted the observed reduction in Na+,K(+)-ATPase activity. In cortical homogenate the protein level of alpha 1 and beta 1 subunits measured in immunoblots was not significantly different in Adx and control rats, indicating that 5 days after adrenalectomy the alpha 1 and beta 1 subunits were present in renal cortical cells to almost normal extent but could not be assembled into a transmembrane functional unit. In support of this conclusion we found that the protein level of both the alpha 1 and beta 1 subunits was significantly lower (P less than 0.001 for both subunits) in microsomes from Adx than in control rats. The mRNA abundance for alpha 1 and beta 1 subunits were not lower in Adx as compared to control rats 1 and 5 days after surgery. However, if Adx rats were given a single dose of betamethasone (600 micrograms kg-1 body wt), a significant 2-fold increase in both alpha 1 and beta 1 mRNAs was observed (P less than 0.05 for both subunits).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
There is little doubt that preserving the spleen will contribute to a much more favourable outcome in patients undergoing splenic surgery, as a result of avoiding the well known risks of splenectomy. Among many operative methods described for splenic salvage, application of autologous fibrin glue (AFG) is particularly promising because of its unique characteristics. The use of AFG has been evaluated and its efficacy and tissue compatibility assessed in the treatment of splenic trauma in 15 partially splenectomized New Zealand White rabbits. The application of the AFG to the resected splenic surface achieved complete haemostasis in all animals. The animals were divided into four groups and were killed at varying intervals ranging from 24 h to 10 weeks. During re-exploration there was no evidence of recurrent bleeding and histopathological examination revealed progressive absorption of the AFG with a minimal inflammatory response. It is concluded that AFG is an effective haemostatic agent with good systemic and local compatibility and can be used in splenic salvage, which thereby avoids the use of non-autologous products with their risks of disease transmission.  相似文献   
997.
The paper is concerned with the results of a radioimmunoassay of the state of the renin-angiotensin-aldosterone system in patients with a neuroendocrine-metabolic type of the hypothalamic syndrome. They received pathogenetic therapy with peritol (an antiserotonin drug) or parlodel (a dopaminergic drug) during three months and routine therapy. The latter was not enough to return to normal the basal blood levels of aldosterone, reaction of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus of the kidneys. Peritol therapy normalized the blood concentration of aldosterone; reactions of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus to insulin hypoglycemia and furosemide acute testing improved considerably. After a course of parlodel therapy blood concentration of aldosterone got to normal, and reaction of the glomerular zone of the adrenocortical substance and the juxtaglomerular apparatus to insulin hypoglycemia was unchanged whereas it improved after furosemide testing.  相似文献   
998.
Determination of the ankle-shoulder index (ASI) was used in addition to clinical examination for the detection and monitoring of patients with obliterating arterial lesions of the legs. In individuals with suspected obliterating lesions, the ASI served as a criterion for the identification of normal, affected and high-risk groups and determined the strategy and duration of treatment and the follow-up schedule. ASI variation following surgery on arteries of the legs was an objective indicator of the efficiency of the operation and furnished indications for repeated surgical intervention to prevent reocclusion.  相似文献   
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