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491.
Genetic equilibria in host-pathogen systems 总被引:1,自引:0,他引:1
K J Leonard 《Phytopathology》1969,59(12):1858-1863
492.
493.
Effects of Serum Deprivation and Cycloheximide on Cell Cycle of Low and High Passage Porcine Fetal Fibroblasts 总被引:1,自引:0,他引:1
MD Goissis HVA Caetano MG Marques FRO de Barros WB Feitosa MP Milazzotto M Binelli MEOA Assumpção JA Visintin 《Reproduction in domestic animals》2007,42(6):660-663
Arrest of cells in G0/G1 cell cycle phase is desired for nuclear transfer procedures. Serum starvation and cell cycle inhibitors are different ways to induce synchronization of the cell cycle. This study investigated the effects of serum starvation and cycloheximide (CHX) on the cell cycle of low (5th) and high (15th) passages fetal porcine fibroblasts. Cell cycle phases were determined using fluorescent activated cell sorting. Fifth passage fibroblast cultures had higher (p < 0.05) proportion of cells in G0/G1 only after 72 h of serum starvation (77.60 ± 0.65) when compared with non‐starved cells (71.44 ± 1.88). Serum starvation for all periods tested induced an increase (p < 0.05) on proportion of cells in G0/G1 on the 15th passage. No significant differences were observed on the 5th passage cultures exposed to CHX, although, on the 15th passage an increase on proportion of cells was observed after all periods of exposure (p < 0.05). These data indicates that high passage cells in vitro are more susceptible to serum starvation and CHX G0/G1 synchronization. 相似文献
494.
A known host-guest assembly, organized only by means of relatively weak dispersive forces, exhibits hitherto unappreciated thermal stability. The hexagonal close-packed arrangement of calix[4]arene contains lattice voids that can occlude small, highly volatile molecules. This host-guest system can be exploited to retain a range of freons, as well as methane, not only well above their normal boiling points, but also at relatively high temperatures and low pressures. The usually overlooked van der Waals interactions in organic crystals can indeed be used in a highly stable supramolecular system for gas storage. 相似文献
495.
Apopo Auleria A. Kariithi Henry M. Ateya Leonard O. Binepal Yatinder S. Sirya Jane H. Dulu Thomas D. Welch Catharine N. Hernandez Sonia M. Afonso Claudio L. 《Tropical animal health and production》2020,52(2):699-710
Tropical Animal Health and Production - Newcastle disease (ND) is a major constraint to Kenya’s poultry production, which is comprised of approximately 80% indigenous chickens (ICs; caged and... 相似文献
496.
JR Sheats H Antoniadis M Hueschen W Leonard J Miller R Moon D Roitman A Stocking 《Science (New York, N.Y.)》1996,273(5277):884-888
Electroluminescence from organic materials has the potential to enable low-cost, full-color flat-panel displays, as well as other emissive products. Some materials have now demonstrated adequate efficiencies (1 to 15 lumens/watt) and lifetimes (>5000 hours) for practical use; however, the factors that govern lifetime remain poorly understood. This article provides a brief review of device principles and applications requirements and focuses on the understanding of reliability issues. 相似文献
497.
Long-term cultures of HTLV-III--infected T cells: a model of cytopathology of T-cell depletion in AIDS 总被引:91,自引:0,他引:91
D Zagury J Bernard R Leonard R Cheynier M Feldman P S Sarin R C Gallo 《Science (New York, N.Y.)》1986,231(4740):850-853
Long-term cultures were established of HTLV-III-infected T4 cells from patients with the acquired immune deficiency syndrome (AIDS) and of T4 cells from normal donors after infection of the cells in vitro. By initially reducing the number of cells per milliliter of culture medium it was possible to grow the infected cells for 50 to 60 days. As with uninfected T cells, immunologic activation of the HTLV-III-infected cells with phytohemagglutinin led to patterns of gene expression typical of T-cell differentiation, such as production of interleukin-2 and expression of interleukin-2 receptors, but in the infected cells immunologic activation also led to expression of HTLV-III, which was followed by cell death. The results revealed a cytopathogenic mechanism that may account for T4 cell depletion in AIDS patients and suggest how repeated antigenic stimulation by infectious agents, such as malaria in Africa, or by allogeneic blood or semen, may be important determinants of the latency period in AIDS. 相似文献
498.
Trans-activator gene of HTLV-II induces IL-2 receptor and IL-2 cellular gene expression 总被引:20,自引:0,他引:20
W C Greene W J Leonard Y Wano P B Svetlik N J Peffer J G Sodroski C A Rosen W C Goh W A Haseltine 《Science (New York, N.Y.)》1986,232(4752):877-880
The human T-lymphotropic viruses types I and II (HTLV-I and -II) have been etiologically linked with certain T-cell leukemias and lymphomas that characteristically display membrane receptors for interleukin-2. The relation of these viruses to this growth factor receptor has remained unexplained. It is demonstrated here that introduction of the trans-activator (tat) gene of HTLV-II into the Jurkat T-lymphoid cell line results in the induction of both interleukin-2 receptor and interleukin-2 gene expression. The coexpression of these cellular genes may play a role in the altering T-cell growth following retroviral infection. 相似文献
499.
Simon Marcel Pierre Knuth Dennis Böhm Leonard Wiltschka Katrin Schatz Marlene Düring Rolf-Alexander 《Journal of Soils and Sediments》2022,22(2):496-508
Journal of Soils and Sediments - Organochlorine pesticides (OCPs) like lindane and DDT have been used extensively after World War II until the 1990s. Still, residues of these pesticides can be... 相似文献
500.