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471.
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473.
A. Dobozy M. Csató Anna Sz. Kenderessy J. Hunyadi L. Kemény N. Simon 《Cellular and molecular life sciences : CMLS》1982,38(4):505-506
Summary An increase in the production of macrophage migration inhibitory factor, chemotactic factor for neutrophils, and skin reactive factor, was observed in lymphocyte cultures if the cells were allowed to age in culture for 24 h. The increased lymphokine production was reduced by adding concanavalin A-stimulated and mitomycin C-treated suppressor cells. It is suggested that the lymphokine production could be regulated by suppressive mononuclear cells.This work was supported by the Scientific Research Council, Ministry of Health, Hungary (Code No. 421 0304011/S). 相似文献
474.
Summary In rats, benzodiazepines seem to induce some amnesia as reported in man. This effect is apparent during the learning of both noxious events and extinction only if the rats are under the drug influence during the conditioning session. 相似文献
475.
An increase in the production of macrophage migration inhibitory factor, chemotactic factor for neutrophils, and skin reactive factor, was observed in lymphocyte cultures if the cells were allowed to age in culture for 24 h. The increased lymphokine production was reduced by adding concanavalin A-stimulated and mitomycin C-treated suppressor cells. It is suggested that the lymphokine production could be regulated by suppressive mononuclear cells. 相似文献
476.
The structural gene coding for myelin-associated proteolipid protein is mutated in jimpy mice 总被引:5,自引:0,他引:5
A Dautigny M G Mattei D Morello P M Alliel D Pham-Dinh L Amar D Arnaud D Simon J F Mattei J L Guenet 《Nature》1986,321(6073):867-869
Mutations affecting developmental processes may allow some insight into the complexity of the biological processes involved. In mice, two mutants that affect myelin formation in the central nervous system, jimpy and shiverer, have proved to be useful models for the study of this process. The predominant proteins in myelin are the major myelin proteolipid (PLP) and the myelin basic proteins (MBP), which together account for 80-90% of total myelin proteins. It has recently been shown that the shiverer mutation is located in the MBP structural gene, but the site of the jimpy mutation, which is X-chromosome-linked and may be similar to the sex-linked dismyelinization human disease, Pelizaeus-Merzbacher disease, remains unclear. Here we provide evidence, based on a combined genetic and biochemical approach, that the sex-linked recessive mutation jimpy is located in the structural gene coding for PLP. 相似文献
477.
Molecular classification of cutaneous malignant melanoma by gene expression profiling 总被引:91,自引:0,他引:91
478.
Humanized xenobiotic response in mice expressing nuclear receptor SXR 总被引:35,自引:0,他引:35
Xie W Barwick JL Downes M Blumberg B Simon CM Nelson MC Neuschwander-Tetri BA Brunt EM Guzelian PS Evans RM 《Nature》2000,406(6794):435-439
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Hadean diamonds in zircon from Jack Hills, Western Australia 总被引:3,自引:0,他引:3
Detrital zircons more than 4 billion years old from the Jack Hills metasedimentary belt, Yilgarn craton, Western Australia, are the oldest identified fragments of the Earth's crust and are unique in preserving information on the earliest evolution of the Earth. Inclusions of quartz, K-feldspar and monazite in the zircons, in combination with an enrichment of light rare-earth elements and an estimated low zircon crystallization temperature, have previously been used as evidence for early recycling of continental crust, leading to the production of granitic melts in the Hadean era. Here we present the discovery of microdiamond inclusions in Jack Hills zircons with an age range from 3,058 +/- 7 to 4,252 +/- 7 million years. These include the oldest known diamonds found in terrestrial rocks, and introduce a new dimension to the debate on the origin of these zircons and the evolution of the early Earth. The spread of ages indicates that either conditions required for diamond formation were repeated several times during early Earth history or that there was significant recycling of ancient diamond. Mineralogical features of the Jack Hills diamonds-such as their occurrence in zircon, their association with graphite and their Raman spectroscopic characteristics-resemble those of diamonds formed during ultrahigh-pressure metamorphism and, unless conditions on the early Earth were unique, imply a relatively thick continental lithosphere and crust-mantle interaction at least 4,250 million years ago. 相似文献