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排序方式: 共有10000条查询结果,搜索用时 971 毫秒
931.
J. K. Lipinski 《CMAJ》1983,129(7):766-768
932.
N Flomenberg K Welte R Mertelsmann N Kernan N Ciobanu S Venuta S Feldman G Kruger D Kirkpatrick B Dupont R O'Reilly 《Journal of immunology (Baltimore, Md. : 1950)》1983,130(6):2644-2650
Five children with primary deficiencies of T cell function were studied to assess the effects of highly purified exogenous Interleukin 2 (IL 2) on their in vitro T cell responses. The lymphocytes from one child with Nezelof's T cell deficiency demonstrated absence of endogenous IL 2 production and improved proliferative responses to mitogen or alloantigen in the presence of exogenous IL 2. Moreover, during in vitro mixed lymphocyte culture in the presence of exogenous IL 2, his lymphocytes were able to develop into cytotoxic effector cells. A second child with Nezelof's syndrome demonstrated a different type of defect. The lymphocytes from this child had less impairment of endogenous IL 2 production. Although IL 2 increased the proliferation of his cells in response to PHA, similar augmentation was not seen after stimulation with OKT3 or alloantigen. In cell-mediated cytotoxicity assays, after mixed lymphocyte culture, natural killer-like activity was strongly boosted in the cultures that contained IL 2, but T cell-mediated cytotoxicity was not. The lymphocytes from three patients with severe combined immunodeficiency did not show improved proliferative responses in the presence of IL 2. Thus, only one of the five patients demonstrated the combination of defective endogenous IL 2 production, but preservation of the ability to respond appropriately to exogenous IL 2. This child may therefore have suffered from a T cell defect pathophysiologically similar to that seen in nude or aged mice. 相似文献
933.
MARGARET K. THAYER 《Systematic Entomology》1987,12(3):389-404
Abstract. The virtually unknown monotypic genus Neophonus Fauvel has been collected in several localities in south-central Chile; it was previously known only from the type locality in Argentina. Field observations of the adults on forest foliage and study of their gut contents suggest that they are mycophagous and eat primarily foliicolous fungi, a habit previously unknown in Staphylinidae. Their mouthparts and tarsi show morphological specializations apparently correlated with these habits. Larvae remain unknown. The phylogenetic relationships of the genus within the omaliine-group of Staphylinidae sensu lato are discussed. 相似文献
934.
Phagocytosis of microspheres in V79 Chinese hamster lung cells was investigated by flow cytometry. Fluorescent microspheres (1.8 micron diameter) were used as the ingesta. Change in the number of V79 cells containing fluorescent microspheres was measured as an index of phagocytic activity. With time there was a sigmoidal increase in cells containing microspheres. The phagocytosis of microspheres is partially explained by two parameters introduced to describe the sigmoidal curves. 相似文献
935.
J J Candelier P Couillin P Eydoux A Boué 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,302(8):303-308
The production of monoclonal antibodies against human embryonic renal cells allowed to display on the adult human kidney some antigens typical of certain structures or tissues: the proximal convoluted tubule for EG 9-11 and EG 19-6 monoclonal antibodies, the glomerular basement membrane for EG 14-1, the urothelium for EE 24-6, the connective tissue for EK 8-1 and EK 17-1 and probably the capsular and tubular basement membranes for EK 8-1. Simultaneously, we could follow the spatial and temporal repartition of the antigens during the renal development. One of them (EI 16-1) seemed to disappear in the adult and might correspond to a foetal type-antigen. 相似文献
936.
937.
938.
Lepcha is the oldest and the first tribe reported from Sikkim, India; majority of its population inhabiting in Dzongu valley, an officially demarcated reserve for Lepcha community, bordering Khangchendzonga Biosphere Reserve, in north district. Lepchas of Dzongu are known for their retention of rich cultural heritage. In view of the on-going cultural and economic changes brought in by the process of globalization, the immediate need was felt to document in details the under-explored ethnomedicinal practices of Lepchas of Dzongu valley. This paper reports 118 species, belonging to 71 families and 108 genera, under ethnomedicinal utility by the Lepchas for curing approximately 66 ailments, which could be grouped under 14 broad categories. Zingiberaceae appeared as the most used family (8 species and 5 genera). As per use pattern, maximum of 30.50% species are to cure stomach related disorders/ailments, followed by 19.49% for curing cut, wounds, inflammation, sprains and joint pains. Administration of medicine orally is recorded in 75% cases. Root and rhizome harvesting targeted 30 species. The changing scenario over time both at socio-cultural front and passing traditional knowledge interests from older to younger generation and rich ethnomicinal wealth of the oldest tribe of Sikkim are discussed in the light of conservation strategies and techniques to adopt. 相似文献
939.
940.
Frank H. Gleason Steve K. Schmidt Agostina V. Marano 《Extremophiles : life under extreme conditions》2010,14(5):417-425
Zoosporic true fungi are thought to be ubiquitous in many ecosystems, especially in cool, moist soils and freshwater habitats
which are rich in organic matter. However, some of the habitats where these fungi are found may periodically experience extreme
conditions, such as soils in extremely dry, hot and cold climates, acidic and alkaline soils, polluted rivers, anaerobic soil
and water, saline soil and water, periglacial soils, oligotrophic soils, tree canopies and hydrothermal vents. It is clear
that many ecotypes of zoosporic true fungi have indeed adapted to extreme or stressful environmental conditions. This conclusion
is supported by studies in both the field and in the laboratory. Therefore, in our opinion, at least some true zoosporic fungi
can be considered to be extremophiles. 相似文献