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951.
I. Carr  P. G. Toner 《CMAJ》1977,116(4):341-342
The role of leukocyte transfusions in the prevention and treatment of infections in adults with granulocytopenia was investigated. Leukocytes were obtained from healthy volunteers by continuous-flow centrifugation. Histocompatibility antigen (HLA)-matched leukocytes were used to assess the prophylactic value of leukocyte transfusions. Seven patients with acute myelogenous leukemia received HLA-matched leukocytes during the period of maximal granulocytopenia associated with initial remission induction therapy; 20 concurrently treated patients who did not receive leukocyte transfusions were the control group. The patients receiving HLA-matched leukocytes had significantly fewer (P = 0.043) infectious episodes (not bacteriologically proven) during the study period, and remission occurred in 5 of the 7, compared with 10 of the 20 controls. In addition, 52 series of two or more ABO-compatible transfusions were given to 50 patients with proven infection or elevated temperature presumed due to infection and a granulocyte count of less than 0.5 X 10(9)/L. Response, indicated by a decrease in temperature, occurred in 23 patients. Leukocyte transfusions thus have an important adjuvant role in the management of patients with severe granulocytopenia.  相似文献   
952.
953.
954.
DNA- and RNA-binding proteins of chromatin from Escherichia coli   总被引:3,自引:0,他引:3  
The different proteins present in chromatin of Escherichia coli have been analyzed by a variety of techniques. The chromatin was isolated using a previously published procedure (Sj?stad, K., Fadnes, P., Krüger, P.G. Lossius, I. and Kleppe, K. (1982) J. Gen. Microbiol. 128, 3037) and solubilized by the action of micrococcal nuclease or DNAase I. The DNA-protein and RNA-protein complexes thus obtained were purified by sucrose gradient centrifugation and isopycnic gradient centrifugation in metrizamide in low ionic strength. The protein: DNA ratio of the DNA-protein complexes was estimated from the latter method and found to be approx. 1.75. The protein components were analyzed further by one- and two-dimensional gel electrophoresis. Approx. 15 major polypeptides were detected in the DNA-protein complex, whereas 10 were present in the RNA-protein complex. The majority of the polypeptides in both complexes had acidic isoelectric pH. The polypeptides in the two complexes differed markedly and only two polypeptides, having molecular weights of 57,000 and 37,000, respectively, were found to be common in both complexes. In agreement with earlier studies, the basic protein HU was not present in the DNA-protein complex. Affinity studies of the proteins from chromatin using DNA- and RNA-Sepharose columns in general confirmed the above conclusions. The two-dimensional gel electrophoretic patterns of the proteins in the different complexes were compared with those of proteins in the inner and outer membranes. Only one of the major polypeptides present in the inner membrane, having a molecular weight of 57,000, was enriched in the DNA-protein complex.  相似文献   
955.
A fermentation system with a plug scheme unit has been developed, offering a variety of solutions to measurement, control, and operational problems. By means of the program unit, e.g., automatic pH control assigned to the dynamic of batch cultures and the feed of different ingredients controlled by a time program or a given variable have been solved. The continuous culture volume was controlled by a level controlled by a level controller equipped with a photosensor. A method was developed for variable control that provide information on the activity of the culture, and allows direct measurement of the different rate values, e.g., generation time or specific product formation rate. Applicability of the direct measurement of generation time is presented in the qualification of molasses and in a static off-line optimization process.  相似文献   
956.
957.
A total of 1 968 persons aged 18-20 years belonging to organized groups were immunized with different doses of polysaccharide meningococcal divaccine, groups A and C, by means of syringes and jet injectors under the conditions of a controlled epidemiological trial. Systemic reactions to the injection of the preparation were found to be absent. Local reactions manifested by inflammation, swelling and tenderness at the site of injection were faintly pronounced and disappeared in 48 hours, which is indicative of low reactogenicity of the preparation under study.  相似文献   
958.
The influence of immunization with P. aeruginosa vaccine on the immune status of volunteer donors has been studied. Immunization with P. aeruginosa vaccine in doses of 0.5-0.5-1.0 ml at intervals of 7 days has been found to lead to the 13-fold increase of the titer of specific antibodies, lasting for 3-4 months, which ensures the possibility of obtaining anti-P. aeruginosa hyperimmune plasma with standard titers. The injection of P. aeruginosa vaccine to donors leads to the activation of humoral immunity simultaneously with the increase of the absolute and relative number of rosette-forming B-lymphocytes without essential changes in the amount of rosette-forming T-lymphocytes.  相似文献   
959.
The method of intravenous administration of UV-irradiated donor plasma to patients with jaundice of different genesis has been tested in the experiments on rats and used clinically in 20 patients. Biochemical and morphological studies have shown that such treatment causes stable improvement in the liver functional state.  相似文献   
960.
Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro (ACTH4-10 analog) at a dose of 0.015 mg/kg failed to alter open field behaviour of rats in the first test series. The peptide abolished amphetamine-induced stimulation of the exploratory and grooming behaviour. Extinction of the rats' exploratory behaviour during second test series in the open field (7 days later) was disturbed when haloperidol or apomorphine were injected before the first test series. When the peptide was administered with haloperidol or apomorphine, the extinction tended to become normal. Heptapeptide failed to change noradrenaline, dopamine or 5-hydroxytryptamine content in the rat forebrain. However, this peptide at a concentration of 10(-4) M moderately diminished tyrosine hydroxylation velocity in the rat striatal or hypothalamic synaptosomes, the effect depending on tyrosine concentration. These data suggest the involvement of catecholaminergic component into the heptapeptide action on the behaviour of rats.  相似文献   
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