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201.
Spontaneous malignant lymphoma in an African green monkey naturally infected with simian T-lymphotropic virus (STLV) 总被引:4,自引:0,他引:4
I Sakakibara Y Sugimoto A Sasagawa S Honjo H Tsujimoto H Nakamura M Hayami 《Journal of medical primatology》1986,15(5):311-318
An African green monkey naturally infected with simian T-lymphotropic virus (STLV) developed spontaneous malignant lymphoma of diffuse pleomorphic type. The clinical, hematological and histopathological characteristics were very similar to those of human adult T-cell leukemia. 相似文献
202.
H Misawa T Hoshi F Kitame M Homma K Nakamura 《Applied and environmental microbiology》1986,51(2):429-431
A methanogenic bacterium with the morphological and physiological properties of the genus Methanobrevibacter was isolated from the feces of a Japanese man who excreted methane in his breath. Indirect immunofluorescence staining revealed that the isolate had an antigenicity unrelated to that of any known members of the genus Methanobrevibacter. 相似文献
203.
The activities of casein kinases 1 and 2 in cytosol fractions prepared from 12 different rat tissues were compared. Casein kinase activities were detected in all tissues examined. Total casein kinase activities of lung, spleen, testis, and thymus were much higher than those of skeletal muscle, cardiac muscle, and adrenal gland. When activities of casein kinases 1 and 2 partially purified from lung, spleen, testis, and thymus prepared from 5 rats were compared, both total and specific activities of these kinases in testis were higher than those in the other tissues. These results indicate that testis is the most suitable tissue in rats for large-scale purification of casein kinase 1 as well as casein kinase 2. 相似文献
204.
F Kitame K Nakamura A Saito Y Suzuki H Sinohara M Homma 《Biochemistry international》1986,12(5):649-652
Rat alpha-1- and alpha-2-macroglobulins as well as rat murinoglobulins I and II were shown to inhibit hemagglutination by influenza C virus. In marked contrast, neither alpha-macroglobulins nor murinoglobulins from mouse or guinea pig plasma had the inhibitory activity. These results suggest that the hemagglutination-inhibiting activity of rat alpha-macroglobulins or murinoglobulins is not related to their protease-binding capacity. 相似文献
205.
T Yoshimura T Miyoshi M Imaki T Tamura M Fujii K Matsumoto T Toumiya Y Hori T Nakamura M Tanada 《Acta biologica Hungarica》1986,37(3-4):235-241
Changes in the activity of serum gamma-glutamyl transpeptidase (gamma-GTP) and the percentage of the gamma-GTP fraction in healthy young men given a high carbohydrate diet (480-636 g/day, 80% of the total energy) for 21 days were examined. Serum total gamma-GTP activity showed no significant change in four healthy young volunteers who received high carbohydrate diet for 21 days. However, the percentage of the gamma-GTP (1) fraction increased significantly (P less than 0.01) from the basal level of 55.6 +/- 4.0% to 67.6 +/- 0.9% on day 10, and then decreased to 58.4 +/- 1.4% on day 21. When the experimental diet was replaced by usual diet, the percentage of the gamma-GTP (1) fraction returned to the same level as before the experiment. It is concluded from the results that the nutrient intake affects the percentage of gamma-GTP (1), but not the total serum gamma-GTP activity. 相似文献
206.
Altered translation initiation factor 2 in the cold-sensitive ssyG mutant affects protein export in Escherichia coli. 总被引:10,自引:0,他引:10 下载免费PDF全文
The Escherichia coli gene secY (pr1A) codes for an integral membrane protein that plays an essential role in protein export. We previously isolated cold-sensitive mutations (ssy) as extragenic suppressors of temperature-sensitive secY24 mutation. Now we show that the ssyG class of mutations are within infB coding for the translation initiation factor IF2. The mutants produce altered forms of IF2 with a cold-sensitive in vitro activity to form a translation initiation complex. The mutation suppresses not only secY24 but also other secretion-defective mutations such as secA51 and rp10215. The beta-galactosidase enzyme activity of the MalE-LacZ 72-47 hybrid protein is strikingly reduced in the ssyG mutant at the permissive high temperature, while the hybrid protein itself is normally synthesized. This effect, which was observed only for the hybrid protein with a functional signal sequence, may result from some alteration in the cellular localization of the protein. These results suggest that IF2 or the translation initiation step can modulate protein export reactions. The isolation of cold-sensitive ssyG mutations in infB provides genetic evidence that IF2 is indeed essential for normal growth of E. coli cells. 相似文献
207.
Sadaaki Iwanaga Takashi Morita Toshiyuki Miyata Takanori Nakamura Jun Aketagawa 《Journal of Protein Chemistry》1986,5(4):255-268
A hemocyte lysate from horseshoe crab produced a gel, when exposed to Gram-negative bacterial endotoxins. This gelation reaction of the lysate, so-called Limulus test, has been widely employed as a simple and very sensitive assay method for endotoxins. Recent biochemical studies on the principle of Limulus test indicate that the hemocytes contain several serine protease zymogens, which constitute a coagulation cascade triggered by endotoxins, and that there is a (1 3)--d-glucan-mediated coagulation pathway which also results in the formation of gel. Up to now, six protein components, designated coagulogen, proclotting enzyme, factor B, factor C, factor G and anti-LPS factor, all of which are closely associated with the endotoxin-mediated coagulation pathway, have been purified and biochemically characterized. Among these components, the complete amino acid sequences of coagulogens isolated from one American and three Asian species of horseshoe crabs have been established. Moreover, the reconstitution experiment using the isolated clotting factors, C, B, proclotting enzyme and coagulogen in the presence of endotoxin, leads to the formation of coagulin get. Based on these results, we propose here a mechanism for the Limulus coagulation cascade. 相似文献
208.
Eiji Ichishima Satoshi Hanzawa Masahiko Watanabe Michio Takeuchi 《Current microbiology》1986,13(4):231-235
Five forms of serine proteinase (EC 3.4.21.14) have been purified fromAspergillus sojae. This paper reports heterogeneity of electrophoretic mobilities, isoelectric points, and kinetic parameters of multiple forms of serine proteinase fromAspergillus sojae, including agerelated changes in thek
cat
/K
m
of electrophoretic species. 相似文献
209.
210.
Ca2+-stimulated inactivation of liver glycogen synthase was observed when a partially purified liver phosphorylase kinase fraction containing glycogen synthase was incubated with ATP-Mg2+. The Ca2+-stimulated portion of this inactivation was partially counteracted by trifluoperazine and slightly stimulated by exogenously added calmodulin. These results suggest that Ca2+-calmodulin may be involved as one of the factors causing this glycogen synthase inactivation. Although the exact mechanism mediated by Ca2+ has not been clearly determined, the possibility of the participation of some Ca2+-dependent protein kinase is discussed. 相似文献