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31.
Correlation of in vitro properties of Rhodococcus (Corynebacterium) equi with virulence for mice 总被引:11,自引:0,他引:11
S Takai T Michizoe K Matsumura M Nagai H Sato S Tsubaki 《Microbiology and immunology》1985,29(12):1175-1184
To study the virulence of Rhodococcus (Corynebacterium) equi, seven ATCC strains of different serotypes were tested for their LD50 in mice, clearance of the organism from the lungs and spleen following intravenous or intratracheal inoculation, and in vitro interaction with murine peritoneal macrophages. Strains ATCC 33704 and 33705 were virulent for mice and multiplied in the lungs and spleen, resulting in death of the animal in 5 days. The other five strains were avirulent for mice. The number of bacteria in the lungs and spleen of mice given these five strains decreased immediately. Pulmonary clearance of strains ATCC 33703, 33706, and 33707 was significantly more rapid than that of the virulent strains ATCC 33704 and 33705 12 hr after inoculation. Complete clearance of the avirulent strain ATCC 33707 occurred by day 14, while that of virulent ATCC 33704 and 33705 strains occurred by day 30. The virulent strains ATCC 33704 and 33705 were resistant not only to phagocytosis but also to intracellular killing by macrophages. Strains ATCC 33702 and 33706 were rapidly killed by macrophages although they were rather resistant to phagocytosis. Strain ATCC 33703 was easily phagocytized though resistant to killing by macrophages. The most avirulent strains, ATCC 33707 and 6939, were easily phagocytized and rapidly killed by macrophages. These results indicate that virulence appeared to be related to the ability of the organisms to resist clearance from the lungs and spleen and to resist phagocytosis and intracellular killing by macrophages. 相似文献
32.
N Kajikawa K Kaibuchi T Matsubara U Kikkawa Y Takai Y Nishizuka K Itoh C Tomioka 《Biochemical and biophysical research communications》1983,116(2):743-750
In platelets, activation of protein kinase C and mobilization of Ca2+ were selectively induced by the addition of 1-oleoyl-2-acetyl-glycerol and a low concentration of A23187, respectively (Kaibuchi, K., Takai, Y., Sawamura, M., Hoshijima, M., Fujikura, T. and Nishizuka, Y. (1983) J. Biol. Chem. 258, 6701-6704). Using this procedure evidence was obtained suggesting that the protein phosphorylation and Ca2+ mobilization were both essential and synergistically effective to cause release of lysosomal acid hydrolases such as N-acetylglucosaminidase. A similar observation was made for the lysosomal enzyme release from rat neutrophils. 相似文献
33.
Fresh-water planarias and a marine planaria are relatively dissimilar in the 5S rRNA sequences. 总被引:3,自引:3,他引:0
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![点击此处可从《Nucleic acids research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The nucleotide sequences from fresh-water Dugesia japonica and marine Planocera reticulata have been determined. The similarity between these two species is only 69%. The Planocera sequence reveals nearly 80% similarity (72-81%) to the sequences of multicellular animals, while the Dugesia sequences are considerably different from them (66-73%). 相似文献
34.
The reversibility of the adenylate cyclase reaction 总被引:1,自引:0,他引:1
K Takai Y Kurashina C Suzuki H Okamoto A Ueki 《The Journal of biological chemistry》1971,246(18):5843-5845
35.
Rapid isolation of nucleoli from detergent purified nuclei of various tumor and tissue culture cells 总被引:1,自引:0,他引:1
A rapid isolation procedure of nucleoli from detergent purified nuclei of some tumor and tissue culture cells is described. The procedure makes use of a non-ionic detergent, Nonidet P40 and sodium deoxycholate to purify nuclei followed by the addition of Ca2+ or Mg2+ to strengthen the nucleoli against sonication. Enzymatically active (with respect to nucleolar RNA polymerase) nucleoli containing undegraded nucleolar RNAs may be isolated from a mouse hepatoma MH134, Ehrlich ascites tumor, HeLa cells, L cells and C3H2K cells with this procedure. 相似文献
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39.
Production of Proteinase on Noncarbohydrate Carbon Sources by Pseudomonas aeruginosa 总被引:2,自引:0,他引:2
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![点击此处可从《Applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Kazuyuki Morihara 《Applied microbiology》1965,13(5):793-797
Proteinase production by Pseudomonas aeruginosa was studied in medium containing noncarbohydrate materials, especially various hydrocarbons, as the sole carbon source. On heavy oil, kerosene, n-paraffinic hydrocarbon of C12, C14, or C16, and propylene glycol, the bacteria grew well and high protinase production was observed. However, production on paraffinic hydrocarbon differed remarkably with strains of varied origins. The elastase-positive strain, IFO 3455, showed abundant growth and high proteinase production on medium containing a paraffin of C12, C14, or C16, whereas the elastase-negative strain, IFO 3080, showed little growth on the same medium. Neither elastase-positive nor elastase-negative strains, however, utilized n-paraffins of C5 to C10, or various aromatic hydrocarbons such as benzene, naphthalene, phenanthrene, and anthracene. The proteinases produced on the noncarbohydrate medium were identical with those produced in glucose medium. 相似文献
40.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds 总被引:7,自引:0,他引:7
Masayuki Yamamoto Shin-ichiro Takai Tetsuro Miki Kazuyoshi Motomura Makoto Okazaki Isamu Nishisho Hideo Tateishi Akira Miyauchi Tasuku Honjo A. J. Pakstis Takesada Mori 《Human genetics》1989,81(3):287-288
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds. 相似文献