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851.
852.
Bie Jia Zheng Keren Gao Xiang Liu Boyang Ma Jun Hayat Muhammad Abid Xiao Jianhua Wang Hongbin 《EcoHealth》2021,18(1):3-12
EcoHealth - Chytridiomycosis, a leading cause for the global decline in the number of amphibians, is caused by the fungal pathogen Batrachochytrium dendrobatidis. In this study, global distribution... 相似文献
853.
Species of the epiphytic fungus Pseudozyma are not pathogenic to plants and can be used as biocontrol agents against plant pathogens. Deciphering how they induce plant defense might contribute to their use for plant protection and expand our understanding of molecular plant–pathogen interactions. Here we show that Pseudozyma aphidis isolate L12, which is known to induce jasmonic acid- and salicylic acid-independent systemic resistance, can also activate local and systemic resistance in an ethylene-independent manner. We also show that P. aphidis localizes exclusively to the surface of the plant leaf and does not penetrate the mesophyll cells of treated leaves. We thus propose that P. aphidis acts via several mechanisms, and is an excellent candidate biocontrol agent. 相似文献
854.
Sigrid A. Lehnert Kate J. Wilson Keren Byrne Stephen S. Moore 《Marine biotechnology (New York, N.Y.)》1999,1(5):465-476
Expressed sequence tag data were generated from complementary DNA libraries created from cephalothorax, eyestalk, and pleopod
tissue of the black tiger shrimp (Penaeus monodon). Significant database matches were found for 48 of 83 nuclear genes sequenced from the cephalothorax library, 22 of 55 nuclear
genes from the eyestalk library, and 6 of 13 nuclear genes from the pleopod library. The putative identities of these genes
reflected the expected tissue specificity. For example, genes for digestive enzymes were identified from the cephalothorax
library and genes involved in the visual and neuroendocrine system from the eyestalk library. A few sequences matched anonymous
EST or genomic sequences, and others contained mini-satellite or microsatellite repeat sequences. The remainder, 31 from the
cephalothorax library, 25 from the eyestalk library, and 5 from the pleopod library, were sequences of high nucleotide complexity
with no matches in any database searched and thus may represent novel genes.
Received February 12, 1999; accepted April 13, 1999 相似文献
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Rat endometrial explants were cultured in a three-dimensional collagen/endothelial cell matrix to measure angiogenic activity, as represented by migration of vascular endothelial cells towards the explants. Minimal endothelial cell migratory activity was observed with endometrial explants taken during the four-day oestrous cycle and days 3 and 4 of pregnancy. In contrast, a surge of endothelial cell migration occurred in response to endometrial explants taken from day-5-pregnant rats. Activity was found in explants taken approximately 5 h prior to implantation, but returned to minimal levels by day 6 of pregnancy. Endothelial cell migration remained minimal in response to both implantation and intersite tissue explants taken from days 6 and 7 of pregnancy. Endometrium from ovariectomised rats produced no endothelial cell migratory activity as measured by this technique. However, near preimplantation levels of endothelial cell migratory activity could be induced in ovariectomised rat endometrium by administering progesterone for 72 hours. Oestrogen given in conjunction with progesterone had no additional effect. These results demonstrate the presence of an endometrial signal that controls endothelial cell migration, and demonstrate this activity can be induced by progesterone without the addition of oestrogen. 相似文献
859.
Genotypic and phenotypic differentiation of Flavobacterium indologenes Yabuuchi et al 1983 from Flavobacterium gleum Holmes et al 1984 总被引:1,自引:0,他引:1
The type and eight strains of Flavobacterium indologenes were clearly differentiated from the type and two reference strains of Flavobacterium gleum by deoxyribonucleic acid-deoxyribonucleic acid homology data and phenotypic characteristics. Phenotypic characteristics useful to differentiate the two species are presented. 相似文献
860.
X.-L. Zhang Y. Komada Yan-Wen Zhou Tong-Xin Chen Haruko Sakai Eiichi Azuma Masaru Ido Minoru Sakurai 《Cancer immunology, immunotherapy : CII》1997,44(1):41-47
Peripheral blood lymphocytes obtained from children with acute lymphoblastic leukemia (ALL) at onset were studied for the
expression of interleukin-2 (IL-2) receptor α-chain (CD25) by two-color flow-cytometric analysis. Stimulated with anti-CD3
monoclonal antibody (mAb) alone, CD25 expression was significantly suppressed in CD4+ T cells from 27 of 48 (56.3%) cases and in CD8+ T cells from 29 of 48 (60.4%) cases. When stimulated with anti-CD3 mAb plus phorbol 12-myristate 13-acetate (PMA), CD25 expression
was clearly restored in certain cases of ALL. When PMA plus ionomycin were used for stimulation of T cells, CD25 was inducible
in a majority of cases. Interestingly CD25 expression upon anti-CD3 mAb stimulation was recovered after complete remission
had been achieved. These observations suggest the presence in ALL children at onset of an in vitro defect in the signal transduction
pathway of the T-cell-receptor/CD3 complex, resulting in inefficient CD25 expression. However, immune-staining analysis indicated
that protein kinase C was normally translocated from the cytosol fraction to the cell membrane fraction. The mobilization
of cytoplasmic free calcium is also normal.
Received: 27 March 1996 / Accepted: 23 December 1996 相似文献