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101.
JL Martal NM Chêne LP Huynh RM L'Haridon PB Reinaud MW Guillomot MA Charlier SY Charpigny 《Canadian Metallurgical Quarterly》1998,80(8-9):755-777
IFN-tau (IFN-tau) constitutes a new class of type I IFN which is not virus-inducible, unlike IFN-alpha and IFN-beta, but is constitutively produced by the trophectoderm of the ruminant conceptus during a very short period in early pregnancy. It plays a pivotal role in the mechanisms of maternal recognition of pregnancy in ruminants and it displays high antiviral and antiproliferative activities across species with a prominent lack of cytotoxicity at high concentrations in vitro in cell culture and possibly in vivo. It exhibits high antiretroviral activity against HIV and exhibits immunosuppressive activity in a multiple sclerosis model and reduces embryo and fetal mortality by stimulation of IL-10 production. In this review all the biochemical and para-hormonal properties of this novel IFN-tau are described in detail: structural characteristics of proteins and genes, trophoblast expression, regulation of its expression, structure of its gene promoter, its absence in human species and in non-ruminant animals, the evolution of the IFN-tau genes, its structure-function relationships with its three-dimensional structure, structural localization of biological activities, its lack of cytotoxicity and its receptor. Surprisingly, for an IFN, IFN-tau is also a pregnancy-embryonic signal with paracrine antiluteolytic activity. In order to maintain luteal progesterone secretion, IFN-tau inhibits PGF-2alpha pulsatile secretion and oxytocin uterine receptivity in early pregnancy. It is believed to suppress pulsatile release of endometrial PGF-2alpha by preventing oxytocin and estrogen receptor expression. Additionally, it directly regulates prostaglandin metabolism and possibly the PGE:PGF-2alpha ratio. 相似文献
102.
NM Verhoeven RJ Wanders BT Poll-The JM Saudubray C Jakobs 《Canadian Metallurgical Quarterly》1998,21(7):697-728
The branched-chain fatty acid phytanic acid is a constituent of the diet, present in diary products, meat and fish. Degradation of this fatty acid in the human body is preceded by activation to phytanoyl-CoA and starts with one cycle of alpha-oxidation. Intermediates in this pathway are 2-hydroxy-phytanoyl-CoA and pristanal; the product is pristanic acid. After activation, pristanic acid is degraded by peroxisomal beta-oxidation. Several disorders have been described in which phytanic acid accumulates, in some cases in combination with pristanic acid. In classical Refsum disease, the enzyme that converts phytanoyl-CoA into 2-hydroxyphytanoyl-CoA--phytanoyl-CoA hydroxylase--is deficient, resulting in highly elevated levels of phytanic acid in blood and tissues. Also in rhizomelic chondrodysplasia punctata, phytanic acid accumulates, owing to a deficiency in the peroxisomal import of proteins with a peroxisomal targeting sequence type 2. In patients affected with generalized peroxisomal disorders, degradation of both phytanic acid and pristanic acid is impaired owing to absence of functional peroxisomes. In bifunctional protein deficiency, the disturbed oxidation of pristanic acid results in elevated levels of this fatty acid and a secondary elevation of phytanic acid. In addition, several variant peroxisomal disorders with unknown aetiology have been described in which phytanic acid and/or pristanic acid accumulate. This review describes the discovery of phytanic acid and pristanic acid and the initial attempts to elucidate the origins and fates of these fatty acids. The current knowledge on the alpha-oxidation and beta-oxidation of these branched-chain fatty acids is summarized. The disorders in which phytanic acid and/or pristanic acid accumulate are described and some remarks are made on the pathogenic mechanisms of elevated levels of phytanic acid and pristanic acid. 相似文献
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NM Agarkov 《Canadian Metallurgical Quarterly》1995,(2):30-32
Communal traumatism represents a heterogeneous phenomenon in whose structure latent, outpatient, hospital, invalidating, and lethal communal traumatism should be distinguished. The said types of traumatism differ by the incidence, share, mean age of the victims, predominating type of injuries, share of multiple injuries, time of application for primary health care, share of ambulance calls, percent share of invalidity, type and duration of invalidity, and outcome of injury. The severity of communal traumatism gradually increases from the first to the last named type and depends on the type of injury and development of complications. 相似文献
105.
This paper describes changes in demographic characteristics and drug use patterns of persons who died while enrolled in a New York City methadone-maintenance program during the years preceding and subsequent to the AIDS epidemic. Persons dying from AIDS were more likely to be younger, Hispanic, and male than those dying from other causes. Drug use increased during the 12-year study period, and the spread of the HIV infection among drug users may be reflected in an increased use of injectable drugs. 相似文献
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107.
S Marmiroli A Bavelloni I Faenza A Sirri A Ognibene V Cenni J Tsukada Y Koyama M Ruzzene A Ferri PE Auron A Toker NM Maraldi 《Canadian Metallurgical Quarterly》1998,438(1-2):49-54
We have developed an on-line archive of neuronal geometry to encourage the use of realistic dendritic structures in morphometry and for neuronal modeling, located at web address www.neuro.soton.ac.uk. Initially we have included full three-dimensional representations of 87 neurons from the hippocampus, obtained following intracellular staining with biocytin and reconstruction using Neurolucida. The archive system includes a structure editor for correcting any departures from valid branching geometry and which allows simple errors in the digitisation to be corrected. The editor employs a platform-independent file format which enforces the constraints that there should be no isolated branches and no closed loops. It also incorporates software for interconversion between the archive format and those used by various neuronal reconstruction and modelling packages. The raw data from digitisation software can be included in the archive as well as edited reconstructions and any further information available. Cross-referenced tables and indexes are updated automatically and are sorted according to a number of fields including the cell type, contributor, submission date and published reference. Both the archive and the structure editor should facilitate the quantitative use of full three-dimensional reconstructions of neurons from the hippocampus and other brain regions. 相似文献
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