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851.
852.
In India's capital New Delhi, four Family Courts were set up between 2009 and 2012, and 12 mediation institutions known as Crime Against Women Cells (CAW cells) were established during the same period. The Indian state has also endorsed gender‐equalising family legislation, mutual‐consent divorce and introduced new language of and for mediation. Together with India's projection of a rising global economy, these recent legal changes have engendered perceptions of a dramatic upturn in formal divorce and of women as liberal legal subjects. In the anthropology of Asia, marital practices have crucially informed our comprehension of modernisation, family formations and moral panics. This article explores the impact of new forms of legal availability on marriage, family and kinship among the metropolitan middle classes. It ethnographically engages with important structural shifts reflected in the intimate lives of Hindu couples, but also foregrounds a cautious narrative of newly imagined jural relations.  相似文献   
853.
This paper examines a model of a flowing water habitat with a hydraulic storage zone in which no flow occurs. In this habitat, one or two microbial populations grow while consuming a single nutrient resource. Conditions for persistence of one population and coexistence of two competing populations are derived from eigenvalue problems, the theory of bifurcation and the theory of monotone dynamical systems. A single population persists if it can invade the trivial steady state of an empty habitat. Under some conditions, persistence occurs in the presence of a hydraulic storage zone when it would not in an otherwise equivalent flowing habitat without such a zone. Coexistence of two competing species occurs if each can invade the semi-trivial steady state established by the other species. Numerical work shows that both coexistence and enhanced persistence due to a storage zone occur for biologically reasonable parameters.  相似文献   
854.
Multi-subunit acetyl-CoA carboxylases   总被引:10,自引:0,他引:10  
Acetyl-CoA carboxylase (ACC) catalyses the first committed step of fatty acid synthesis, the carboxylation of acetyl-CoA to malonyl-CoA. Two physically distinct types of enzymes are found in nature. Bacterial and most plant chloroplasts contain a multi-subunit ACC (MS-ACC) enzyme that is readily dissociated into its component proteins. Mammals, fungi, and plant cytosols contain the second type of ACC, a single large multifunctional polypeptide. This review will focus on the structures, regulation, and enzymatic mechanisms of the bacterial and plant MS-ACCs.  相似文献   
855.
856.
Oxidative stress is one of the major causes of degenerative conditions occurring at cellular level with serious health implications. This study was aimed at investigating the antioxidative potentials of probiotic lactobacilli of Indian gut origin and their ability to augment antioxidant defense enzyme systems in the host cells under oxidative stress conditions. A total of 39 Lactobacillus cultures were assessed for their resistance against reactive oxygen species. Most of the cultures were moderately to strongly resistant towards 0.4 mM H(2)O(2). The Lactobacillus isolate CH4 was the most H(2)O(2) resistant culture with only 0.06 log cycle reduction. Majority of the cultures demonstrated high resistance towards hydroxyl ions and Lp21 was the most resistant with log count reduction of 0.20 fold only. Almost all the cultures were also quite resistant to superoxide anions. Lp21 also showed the highest superoxide dismutase content (0.8971 U). Amongst the 39 cultures, Lactobacillus spp. S3 showed the highest total antioxidative activity of 77.85 ± 0.13 % followed by Lp55 (56.1 ± 1.2 %) in terms of per cent inhibition of linolenic acid oxidation. Lp9 up-regulated the expression of superoxide dismutase 2 gene in HT-29 cells both at 0.1 mM (1.997 folds) and 1.0 mM H(2)O(2) (2.058 folds) concentrations. In case of glutathione peroxidase-1, Lp9, Lp91 and Lp55 showed significant (P < 0.001) up-regulation in the gene expression to the level of 5.451, 8.706 and 10.083 folds, respectively when HT-29 was challenged with 0.1 mM H(2)O(2). The expression of catalase gene was also significantly up-regulated by all the cultures at 0.1 mM H(2)O(2) conditions. It can be concluded that the antioxidative efficacy of the putative probiotic lactobacilli varied considerably between species and strains and the potential strains can be explored as prospective antioxidants to manage oxidative stress induced diseases.  相似文献   
857.
Cytochrome P450 (P450) 2D6 was first identified as the polymorphic human debrisoquine hydroxylase and subsequently shown to catalyze the oxidation of a variety of drugs containing a basic nitrogen. Residue Asp301 has been characterized as being involved in electrostatic interactions with substrates on the basis of homology modeling and site-directed mutagenesis experiments [Ellis, S. W., Hayhurst, G. P., Smith, G., Lightfoot, T., Wong, M. M. S., Simula, A. P., Ackland, M. J., Sternberg, M. J. E., Lennard, M. S., Tucker, G. T., and Wolf, C. R. (1995) J. Biol. Chem. 270, 29055-29058]. However, pharmacophore models based on the role of Asp301 in substrate binding are compromised by reports of catalytic activity toward substrates devoid of a basic nitrogen, which have generally been ignored. We characterized a high-affinity ligand for P450 2D6, also devoid of a basic nitrogen atom, spirosulfonamide [4-[3-(4-fluorophenyl)-2-oxo-1-oxaspiro[4.4]non-3-en-4-yl]benzenesulfonamide], with K(s) 1.6 microM. Spirosulfonamide is a substrate for P450 2D6 (k(cat) 6.5 min(-)(1) for the formation of a syn spiromethylene carbinol, K(m) 7 microM). Mutation of Asp301 to neutral residues (Asn, Ser, Gly) did not substantially affect the binding of spirosulfonamide (K(s) 2.5-3.5 microM). However, the hydroxylation of spirosulfonamide was attenuated in these mutants to the same extent (90%) as for the classic nitrogenous substrate bufuralol, and the effect of the D301N substitution was manifested on k(cat) but not K(m). Analogues of spirosulfonamide were also evaluated as ligands and substrates. Analogues in which the sulfonamide moiety was modified to an amide, thioamide, methyl sulfone, or hydrogen were ligands with K(s) values of 1.7-32 microM. All were substrates, and the methyl sulfone analogue was oxidized to the syn spiromethylene carbinol analogue of the major spirosulfonamide product. The D301N mutation produced varying changes in the oxidation patterns of the spirosulfonamide analogues. The peptidometic ritonavir and the steroids progesterone and testosterone had been reported to be substrates for P450 2D6, but the affinities (K(s)) were unknown; these were estimated to be 1.2, 1.5, and 15 microM, respectively (cf. 6 microM for the classic substrate bufuralol). The results are consistent with a role of Asp301 other than electrostatic interaction with a positively charged ligand. H-Bonding or electrostatic interactions probably enhance binding of some substrates, but our results show that it is not required for all substrates and explain why predictive models fail to recognize the proclivity for many substrates, especially those containing no basic nitrogen.  相似文献   
858.
859.
Two effective strains of green gram rhizobia S24 (slow growing and Hup+) and M11 (fast growing and Hup-) were tested for leghemoglobin production in nodules and effectivity on six species of cow pea miscellany hosts. Both strains nodulate green gram [Vigna radiata (L.) (Wilczek)], black gram [Vigna mungo (L.) (Hepper)], cow pea [Vigna unguiqulata (L.)], moth bean [Vigna aconitifolia (Jacq.) (Marechel)], Cluster bean [Cyamopsis tetragonoloba (L.) (Taub.)] and pigeon pea [Cajanus cajan (L.)]. In all these hosts, nodules formed by strain M11 contained 1.5 to 2 times more leghemoglobin than the nodules formed by strain S24. Gel electrophoresis of nodule contents of different host species showed a high concentration of a fast-moving ferricoxy leghemoglobin in the nodules of plants inoculated with strain M11 as compared to that of strain S24. Strain M11, however, was relatively less effective than strain S24 on black gram, cow pea and moth bean and was at par with the later on green gram, cluster bean and pigeon pea. Hydrogen recycling ability of the strain S24 was observed in nodules of all the host species. The effective functioning of strain S24 at low levels of leghemoglobin suggests an involvement of recycling hydrogenase in maintaining an appropriate oxidation-reduction potential in nodules.Abbreviations Lb Leghemoglobin - Cvr cultivar  相似文献   
860.
We used automated sperm morphology analysis to investigate rat sperm morphometry and morphology in Sprague-Dawley and Wistar rats in three research centers to develop normal baseline values for sperm morphometry and to quantify the percentage of morphologically normal sperm in healthy rats. The participating centers were IRSN in Paris, France (Sprague-Dawley rats), University of the Western Cape, South Africa (Wistar rats) and Stellenbosch University (Wistar rats), South Africa. All three centers used identical sperm isolation techniques from the cauda epididymis, the same staining protocols, identical computer-aided sperm morphometry analysis (CASMA) software and microscopes with similar optics. With CASMA, fully automated analysis of the different parts of stained sperm, e.g., head, acrosome, mid-piece, can be performed, many sperm morphometric features can be measured accurately and eventually normal sperm morphology can be defined. We found that it is possible to distinguish sperm morphometric characteristics of Sprague-Dawley and Wistar rats. We also developed cut-off values for evaluating the percentage normal sperm in these two rat strains using the automatic analysis mode. Normal sperm morphology varied between 67 and 74% by contrast with previous findings of > 90%.  相似文献   
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