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排序方式: 共有266条查询结果,搜索用时 31 毫秒
31.
32.
CD43, a molecule defective in Wiskott-Aldrich syndrome, binds ICAM-1. 总被引:12,自引:0,他引:12
THE protein CD43 (also known as sialophorin, leukosialin, large sialoglycoprotein or gp115) is expressed on the surface of T lymphocytes, monocytes, neutrophils, platelets and some B lymphocytes. Expression of CD43 is deficient and/or defective in the X-chromosome-linked immunodeficiency disorder Wiscott-Aldrich syndrome, suggesting that CD43 might have a role in T-cell activation. We have shown that expression of human CD43 in an HLA-DR-specific murine T-cell hybridoma enhances the antigen-specific response to stimulation by the human lymphoblastoid cell line Daudi, and that Daudi cells bind specifically to purified immobilized CD43. These data indicate that the specific interaction of CD43 with a ligand on the surface of Daudi cells might contribute to T-cell activation. Here we report evidence that intercellular adhesion molecule-1 (ICAM-1, or CD54), is a ligand for CD43. 相似文献
33.
B. H. Park 《Cellular and molecular life sciences : CMLS》1980,36(4):473-474
Summary A new method is described in which human neutrophils were made to migrate upward and against gravity. Thus, the possible effect of gravity on cell migration and consequent detachment of cell after migration have been eliminated.Supported in part by N.I.H. grants: No.HL19628-03, No. DE04898, No. CA24215 and No.RR05493). 相似文献
34.
Cellular responses to mild heat stress 总被引:12,自引:0,他引:12
Since its discovery in 1962 by Ritossa, the heat shock response has been extensively studied by a number of investigators to understand the molecular mechanism underlying the cellular response to heat stress. The most well characterized heat shock response is induction of the heat shock proteins that function as molecular chaperones and exert cell cycle regulatory and anti-apoptotic activities. While most investigators have focused their studies on the toxic effects of heat stress in organisms such as severe heat stress-induced cell cycle arrest and apoptosis, the cellular response to fever-ranged mild heat stress has been rather underestimated. However, the cellular response to mild heat stress is likely to be more important in a physiological sense than that to severe heat stress because the body temperature of homeothermic animals increases by only 1–2°C during febrile diseases. Here we provide information that mild heat stress does have some beneficial role in organisms via positively regulating cell proliferation and differentiation, and immune response in mammalian cells.Received 14 May 2004; received after revision 2 August 2004; accepted 16 August 2004 相似文献
35.
Tuning clathrate hydrates for hydrogen storage 总被引:1,自引:0,他引:1
Lee H Lee JW Kim DY Park J Seo YT Zeng H Moudrakovski IL Ratcliffe CI Ripmeester JA 《Nature》2005,434(7034):743-746
The storage of large quantities of hydrogen at safe pressures is a key factor in establishing a hydrogen-based economy. Previous strategies--where hydrogen has been bound chemically, adsorbed in materials with permanent void space or stored in hybrid materials that combine these elements--have problems arising from either technical considerations or materials cost. A recently reported clathrate hydrate of hydrogen exhibiting two different-sized cages does seem to meet the necessary storage requirements; however, the extreme pressures (approximately 2 kbar) required to produce the material make it impractical. The synthesis pressure can be decreased by filling the larger cavity with tetrahydrofuran (THF) to stabilize the material, but the potential storage capacity of the material is compromised with this approach. Here we report that hydrogen storage capacities in THF-containing binary-clathrate hydrates can be increased to approximately 4 wt% at modest pressures by tuning their composition to allow the hydrogen guests to enter both the larger and the smaller cages, while retaining low-pressure stability. The tuning mechanism is quite general and convenient, using water-soluble hydrate promoters and various small gaseous guests. 相似文献
36.
Cell division during regeneration in Hydra 总被引:1,自引:0,他引:1
37.
W. Wang C. Sprague M. Yokoyama H. S. Park 《Cellular and molecular life sciences : CMLS》1973,29(7):871-872
Zusammenfassung Es wird eine Radial-Immun.-Diffusionsmethode verwendet, um durch Vergleich der IgM-Antikörper im Nabelschnurblut zu bestimmen, ob im den homologen mütterlichen Proben eine asymptotische Infektion stattgefunden hat. Es ergab sich, dass das benutzte Verfahren nicht zur Klärung der gestellten Frage geeignet ist.
This study was supported by a Kapiolani Maternity Hospital Research Grant and the Mrs. Lois A. Mayer Family Fund.
Acknowledgment. The authors indebted to Mrs.L. Hann, MT (ASCP) for her technical assistance and Mr.V. T. Oi for his critical review of this paper. 相似文献
This study was supported by a Kapiolani Maternity Hospital Research Grant and the Mrs. Lois A. Mayer Family Fund.
Acknowledgment. The authors indebted to Mrs.L. Hann, MT (ASCP) for her technical assistance and Mr.V. T. Oi for his critical review of this paper. 相似文献
38.
The volcanic layer may be only 200 m thick at 45 degrees N and oxidation of titanomagnetite may be responsible for the decrease in amplitude of the magnetic anomalies away from the ridge axis. 相似文献
39.
40.
Hydrogen is a promising energy carrier that can potentially facilitate a transition from
fossil fuels to sustainable energy sources without producing harmful by-products. Prior to realizing
a hydrogen economy, however, viable hydrogen storage materials must be developed. Physical
adsorption in porous solids provides an opportunity for hydrogen storage under low-stringency
conditions. Physically adsorbed hydrogen molecules are weakly bound to a surface and, hence, are
easily released. Among the various surface candidates, porous carbons appear to provide efficient
hydrogen storage, with the advantages that porous carbon is relatively low-cost to produce and is
easily prepared. In this review, we summarize the preparation methods, pore characteristics, and
hydrogen storage capacities of representative nanoporous carbons, including activated carbons,
zeolite-templated carbon, and carbide-derived carbon. We focus particularly on a series of
nanoporous carbons developed recently: metal–organic framework-derived carbons, which exhibit
promising properties for use in hydrogen storage applications. 相似文献