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101.
D B Watson G F Burns I R Mackay 《Journal of immunology (Baltimore, Md. : 1950)》1983,130(5):2442-2447
Epstein Barr virus was used to transform the B lymphocytes infiltrating metastatic tumor tissue from seven patients with melanoma. In this way it was possible to establish continuously growing B lymphoblastoid cell lines (LCL) derived from the tumor-infiltrating B lymphocytes from each of the seven patients. Antibody production of up to 50 micrograms/ml could be achieved by such cultures, and the lymphoblastoid cells could be cloned readily by limit dilution on a feeder layer of irradiated fetal fibroblasts. Preliminary analysis of the antibodies produced by lymphoblastoid cell lines established from tumors from two of the patients indicated that most were of IgM type and bound to a panel of melanoma cell target cells, as well as to some nonmelanoma tumor cell lines. Cloned LCL were produced from the tumor-infiltrating B cells from one of the patients, and of 100 such clones tested, 9% secreted antibody that bound to autologous tumor cells, and one of these clones produced antibody that appeared to be melanoma specific. 相似文献
102.
S R Watson T B Miller T J Redington W E Bullock 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(2):984-990
Previous studies have shown that mice infected i.v. with 6 X 10(5) yeast phase Histoplasma capsulatum (Hc) develop suppressed immune responses during weeks 1 to 4 of infection but that by weeks 8 to 12 of infection these responses return to normal. In this study total and differential cell counts showed that as early as the third day of infection there was a marked reduction in the number of lymphocytes recovered from the peripheral blood, bone marrow, and thymus of infected animals. Concomitantly, there was an increase in the number of splenic lymphocytes. By day 28 both the total and differential cell counts were similar in both infected and normal animals. Flow microfluorometric (FMF) studies comparing the Thy-1.2, Lyt-1, Lyt-2, and surface immunoglobulin (slg) phenotypes of lymphocytes from normal and infected mice were performed. Between days 5 and 7 the thymocytes from infected mice displayed a higher relative fluorescence intensity (RFI) of the Thy-1.2 marker than normal thymocytes, whereas at day 10, the RFI was less than that of normal thymic lymphocytes. Between days 7 and 10 of infection the RFI of the Lyt-2 marker was less on thymocytes from Hc-infected mice; however, there was no change in the Lyt-1 marker. Examination of these lymphocyte markers in blood, spleen, and mesenteric lymph nodes showed that there were decreases in the RFI of both the Thy-1.2 and Lyt-2 between days 5 and 10 of infection. No changes were observed in the Lyt-1 or slg markers. By day 28 there were no differences between the normal and infected mice with respect to any surface marker in any of the organs studied. In other experiments, the effect of adrenalectomy before infection on these surface markers was studied. Absolute numbers of Thy-1.2+, Lyt-1+, and Lyt-2+ cells were significantly increased in the spleen and significantly decreased in the thymus and peripheral blood of infected mice relative to normal controls. These studies suggest that there is a migration of cells from the thymus, blood, and bone marrow to the spleens of mice with disseminated Hc infection. 相似文献
103.
104.
The action of nitrous acid on C-teichoic acid (C-substance) from the walls of Diplococcus pneumoniae 总被引:1,自引:1,他引:0 下载免费PDF全文
1. C-teichoic acid (C-substance) from the walls of Diplococcus pneumoniae contained free amino groups accessible to attack by nitrous acid. Treatment with nitrous acid, followed by reduction with borohydride and hydrolysis with acid, gave ribitol, glucitol and their respective phosphates. 2. Hydrolysis of the polymer with alkali followed by treatment of products with nitrous acid yielded glucose. 3. When alkali hydrolysis was followed by treatment with a phosphomonoesterase, nitrous acid degradation of C-substance yielded glucose and a disaccharide identified as 2-O-(N-acetylgalactosaminyl)-d-ribitol. 4. A partial structure for C-teichoic acid was deduced in which the order of the constituent residues and the position of phosphodiester linkages were established. 相似文献
105.
Ribonuclease H activity present in purified DNA polymerase from avian myeloblastosis virus 总被引:7,自引:0,他引:7
K.F. Watson K. Mölling H. Bauer 《Biochemical and biophysical research communications》1973,51(1):232-240
The presence of ribonuclease H activity in the purified complex of DNA polymerase from avian myeloblastosis virus is described. Evidence includes co-chromatography of the two activities during all purification steps; the presence of ribonuclease H activity in the purified two-polypeptide complex of DNA polymerase; ion requirements for optimal activity of purified ribonuclease H are identical to those for the purified DNA polymerase; and monospecific antiserum against purified DNA polymerase neutralizes the ribonuclease H activity. 相似文献
106.
Fatty acids in the lipids of 19 marine and terrestrial nitrifying bacteria have been analyzed. Ammonia-oxidizing bacteria have a very simple acid composition; palmitic and palmitoleic acid account for 96 to 100% of the total acids. The fatty acids of nitrite-oxidizing bacteria cover a wider range, from C(14) to C(19), but from two to four acids still account for more than 80% of the total acids. Branched iso- and anteiso-acids are present in traces only in 2 of the 19 bacteria. The chemical and morphological similarity between blue-green algae and these bacteria is discussed. 相似文献
107.
Comparative Intermediary Metabolism of Vegetative Cells and Microcysts of Myxococcus xanthus 总被引:12,自引:8,他引:4
Crude extracts of both vegetative cells and glycerol-induced microcysts of Myxococcus xanthus contained the following enzyme activities: phosphofructokinase, phosphoglucoisomerase, fructose-1,6-diphosphatase, fructosediphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphopyruvate carboxylase, citrate synthase, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, phosphoglucomutase, and uridine diphosphate glucose pyrophosphorylase. With the exception of isocitrate dehydrogenase, which was present at a fivefold higher concentration in microcysts, all activities in extracts from both types of cells were essentially equal. Hexokinase and pyruvate kinase could not be detected in extracts from either type of cell. Microcysts metabolized acetate at a lower rate than did vegetative cells. Most of this decrease was reflected in a substantial decrease in ability of microcysts to oxidize acetate to CO(2). In addition, microcysts and vegetative cells showed a different distribution of (14)C-label from incorporated acetate. 相似文献
108.
Respiratory Components of Aspergillus niger Mitochondria 总被引:1,自引:1,他引:0
The respiratory components of tightly coupled mitochondria from the filamentous fungus Aspergillus niger were studied. Cytochromes a + a(3), b, and c + c(1) were identified by difference spectra. The cytochrome spectra were qualitatively similar to yeast and rat liver mitochondria. The mitochondria contained, per gram of protein, an average of 2.9 and 7.0 mumoles of ubiquinone and nicotinamide adenine dinucleotide, respectively. 相似文献
109.
110.
THREE SIBLING SPECIES OF ALECTORIS PARTRIDGE 总被引:3,自引:0,他引:3