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411.
Summary This report describes a study of the active T-RFC, the total T-RFC, and the in vitro lymphocyte response to PHA stimulation in patients with inoperable, locally advanced, lung cancer before and monthly after either radiotherapy alone (RT) or RT-BCG (TICE strain). Pre-RT active and total T-RFC values were seen to be prognostic to patient survival. Immunoenhancement was demonstrated for RT-BCG patients who had significantly higher percentages of active T-RFC and greater PHA responses post-RT than patients treated by RT alone. These data suggest that the active T-RFC may reflect increased nonspecific immunity induced by BCG and be a good correlate to patient immunocompetence. The comparative relevance of the active and total T-RFC to patient clinical progress and survival are discussed.Abbreviations BCG= Bacillus Calmette-Guerin - RT= radiotherapy - T-lymphocyte= thymus-dependent lymphocyte - RFC= rosette-forming cell - PHA= phytohemagglutinin - SRBC= sheep red blood cells - PBL= peripheral blood lymphocyte Supported by the Medical Research Service of the Veterans AdministrationWe acknowledge the excellent technical assistance of Mrs. Barbara Kase and Mrs. Sue Brozio  相似文献   
412.
An acylphosphatase has been purified from turkey muscle in a rapid and high-yield way. The enzyme has been characterized for structural, kinetic, and immunological parameters, as well as with regard to its stability to thermal, urea, and phenylglyoxal inactivation. The enzyme is quite different from the turkey muscular isoenzyme, and shows structural and kinetic properties that are very similar to those previously reported for the erythrocyte isoenzyme from human erythrocytes and from chicken muscle. From the data reported it appears that this enzyme corresponds to the acylphosphatase erythrocyte isoenzyme. Unlike the erythrocyte isoenzymes studied so far, this enzyme is able to cross-react with antibodies that are raised against the muscular isoenzyme.  相似文献   
413.
The authors describe a method of obtaining monospecific serum against secretory IgA and the corresponding standard. An immunochemically pure (11.6S) secretory human IgA was extracted from the colostrum by salt fractionation and gel-filtration through Sephadex G-200 and Sepharose 6B; this IgA was used as an antigen for the immunization and the standard for the quantitative determination of SIgA in the secretions. Monospecific anti-SC-serum was obtained by successive exhaustion of the antiserum against the S IgA immunosorbents prepared from normal human serum and the serum of a patient suffering from A myeloma containing polymeric IgA forms.  相似文献   
414.
Fractionation of sarcoplasmic reticulum vesicles from rabbit skeletal muscle was performed by solubilization of the vesicles in the presence of deoxycholate, followed by sucrose density gradient centrifugation and gel filtration chromatography. This procedure permitted the isolation of essentially pure Ca2+-ATPase; this enzyme showed ATPase as well as acylphosphatase activity, both activities being clearly enhanced by deoxycholate. The acylphosphatase activity of the purified Ca2+-ATPase was characterized with regard to some kinetic properties, such as pH, Mg2+, Ca2+, and deoxycholate dependence, and substrate affinity, determined in the presence of acetylphosphate, succinylphosphate, carbamylphosphate, and benzoylphosphate; in addition, the stability of both activities was checked in time-course experiments. The main similarities between the two activities, such as the Mg2+ requirement, the deoxycholate activation, and the pH dependence, together with the competitive inhibition of the benzoylphosphatase activity by ATP, the inhibition of both activities by tris(bathophenanthroline)-Fe2+, and the relief of this inhibitory effect by carbonylcyanide-4-trifluoromethoxyphenyl hydrazone support the hypothesis that acylphosphatase and ATPase activities of sarcoplasmic reticulum vesicles reside in the same active site of the enzyme. With regard to possible relationships between acylphosphatase activity of the purified Ca2+-ATPase and “soluble” acylphosphatase present in the 100,000g supernatant fraction, comparison of some kinetic and structural parameters indicate that these two activities are supported by quite different enzymes.  相似文献   
415.
The products of the hydrolysis of sucrose and palatinose by the sucrase-isomaltase complex from rabbit small intestine were investigated by persilylation followed by gas-liquid chromatography and mass spectrometry. If the hydrolysis is carried out in H218O, the heavy oxygen is found exclusively at the Ci of the alpha-glucopyranose formed. The 18O enrichment equals that of the incubation medium. The oxygen exchange between the monosaccharides and water is not accelerated by the sucrase-isomaltase complex. These observations show that the bond split by the sucarse and the isomaltase moiety of the complex is the one between glucosyl-Ci and the glucosyl oxygen. They agree with the mechanism proposed for these carbohydrases in the accompanying paper (Cogoli, A., and Semenza, G. (1975) J. Biol. Chem. 250, 7802-7809) involving the formation of an oxocarbonium ion.  相似文献   
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Rabbit antilymphocyte serum (ALS) and complement were used in doses killing 50% of lymphocytes (staining with a 1% solution of trypan blue). In rosette-forming and blast-cell transformation reactions the counts of rosette forming and transformed cells were 60 and 24% respectively, as compared to those in controls. After adding 0.1 ml of 10 mM solution of potassium hydroxyethylene-diphosphonate belonging to a group of synthetic diphosphonates, the protective effect was observed shown by that the counts of rosette-forming and transformed lymphocytes did not differ from the control ones, wherein the reactions were produced with intact cells.  相似文献   
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