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991.
The ability of serotonin, melatonin and beta-endorphin synthesis by secreting granules of natural killer cells (NK cells) was established by immunohistochemical method. It was shown that cytotoxic effect of NK cells can be to a certain extent related to the presence of secreting granules. A possible direct contribution of NK cell-synthesized hormones to the natural killer antitumour effect is discussed.  相似文献   
992.
Glutathione reductase has been purified to homogeneity by a method which is an improvement of an earlier procedure (Carlberg, I. and Mannervik, B. (1975) J. Biol. Chem. 250, 5475-5480). The new steps in the purification scheme include affinity chromatography on 2',5' ADP-Sepharose 4B. Antibodies to glutathione reductase from rat liver were raised in rabbits and used for analysis of the enzyme by quantitative 'rocket' immunoelectrophoresis. Glutathione reductase from human erythrocytes, porcine erythrocytes, and calf-liver gave precipitin lines showing partial identity with the rat liver enzyme in Ouchterlony double diffusion experiments. Enzyme from spinach, yeast (Saccharomyces cerevisiae), and the photosynthetic bacterium Rhodospirillum rubrum did not give precipitates with the antibodies to the enzyme from rat liver. Titration of glutathione reductase from the different sources with antibodies confirmed the cross-reactivity of the mammalian enzymes; the human enzyme giving the strongest heterologous reaction. No reaction was observed with the enzyme from spinach, yeast, and Rhodospirillum rubrum. NADPH, NADP+, and 2',5' ADP were found to inhibit the interaction between antibodies and glutathione reductase from rat liver and human erythrocytes. NADH, glutathione, or glutathione disulfide did not protect the enzyme from reacting with the antibodies. It is concluded that glutathione reductase has an antigenic binding site for the antibodies at the pyridine nucleotide-binding site of the enzyme molecule.  相似文献   
993.
The portal vein and its main affluents. An anatomic and morphometric study   总被引:1,自引:0,他引:1  
There are reported the results of certain measurements made on 158 human cadavers of both sexes. A series of main parameters are given, such as the distance between the superior mesenteric vein and on the one hand its confluence with other vessels and on the other hand the pancreas and the horizontal part of the duodenum: the distance between the superior mesenteric vein together with the portal vein, and the inferior caval vein; the diameters of the portal trunk and the confluence angle between the roots of the portal vein. The results reflect the possibility to perform a troncular portocaval anastomosis in at least 90 per cent of the cases. The authors' attention was, however, directed towards the anatomy of the superior mesenteric vein, as this vessel is preferred by some surgeons in the achievement of the portocaval anastomosis.  相似文献   
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In recent attempts to isolate the factor causing paralysis in rats infected with a mousepassed KBG 173 strain of Plasmodium berghei Splenectomy was employed. The effects of Splenectomy on the paralyzing syndrome are discussed in the present report. Paralysis was inhibited in rats splenectomized prior to inoculation. Serial bloodpassaging of the strain in the splenectomized host however, apparently enhanced its virulence. Spleen-intact rats used as controls exhibited a marked increase in incidence of paralysis. Rats splenectomized a day before paralysis became evident were paralyzed significantly more frequently than those splenectomized a day earlier, indicating the apparent requirement of an incubation period for the expression of the paralytic effect. The enhanced virulence did not appear to be related to the level of parasitemia of the splenectomized rats used as donors. The spleen appears to provide the optimal conditions required for the elaboration of the paralyzing factor.  相似文献   
998.
Prophylactic activity and side action of antiinfluenza lactoglobulin were studied under conditions of controlled epidemiological trial in 6361 persons during the epidemiological rise of influenza incidence. The data obtained pointed to the absence of any protective effect of antiinfluenza lactoglobulin. Marked allergenic properties of lactoglobulin and development of sensitization in the persons under observation were found during the study of the side-effect of the preparation. Thus, the absence of prophylactic efficacy and the sensitizing action of antiinfluenza lactoglobulin pointed to the inexpediency of its use for prophylactic and therapeutic purpose.  相似文献   
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