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71.

Background  

The potential effect of age-related factors on health-related quality of life (HRQOL) of patients with epilepsy has rarely been analyzed in the literature.  相似文献   
72.
The possible contribution of tumor necrosis factor-α (TNF-α) to the development of obesity-associated insulin resistance in humans is still controversial. Our study investigated the effect of TNF-α neutralization on insulin resistance in healthy, obese and insulin resistant men. We performed a prospective, randomized, double-blind placebo-controlled trial in nine young, healthy obese male subjects with metabolic syndrome and insulin resistance. Volunteers received three infusions (wks 0, 2 and 6) of infliximab or placebo. Insulin resistance was measured at baseline and after 70 d by homeostatic model assessment (HOMA) index as well as by minimal model analysis of an intravenous glucose tolerance test. Endothelial function was accessed before and after intervention by flow mediated dilation. Infliximab improved the inflammatory status as indicated by reduced high sensitivity C-reactive protein (hsCRP) and fibrinogen levels (2.77 ± 0.6 to 1.8 ± 0.5 μg/L, and 3.42 ± 0.18 to 3.18 ± 0.28 g/L; (day 0 and day 70, P = 0.020 and 0.037 respectively), but did not improve insulin resistance (HOMA index and intravenous glucose-tolerance test [ivGGT]) or endothelial function. Despite improvements in inflammatory status, chronic TNF-α neutralization does not improve insulin resistance or endothelial function in seemingly healthy, but obese, insulin-resistant volunteers. This study severely questions the proposal that TNF-α is a causative link between adiposity and insulin resistance.  相似文献   
73.
In the last decade efforts have been carried out by the scientific community aimed at building integrated frameworks to support the decision-making process when sustainability issues are addressed. This paper proposes a further advancement in integrated assessment procedures by setting up an operational multi-scale and transparent framework, which comprises the assessment of European regions in terms of sustainability, and the identification of the impact that policy options might have on the sustainability of these regions. The framework is designed for use in ex ante sustainability impact assessment of policy scenarios on multifunctionality of land use and integrates economic, environmental and social issues across a variety of sectors (agriculture, forestry, transport, tourism and energy). The proposed method provides a conceptual framework applicable at different scales (European, regional), and takes into account the great variability of European regions. The described methodology is based on linear additive models to weight and aggregate selected indicators to a set of land use functions identified to describe the goods and services provided by the different land uses that summarise the most relevant economic, environmental and social issues of a region. The framework is designed to allow the evaluation of impacts at an international scale (e.g. the European Union), or on selected regions.The aggregation framework can be used to evaluate the impact that policy options have on the sustainability of multifunctional land use systems with competing demands. A conceptual envelope, called the “trade-off evaluation space”, delineates all possible developments in the functions of the land. The sustainability limits identify the subset of ‘acceptable’ policy options within the trade-off evaluation space, so that the distance of each land use function from sustainability limits can be estimated and trade-offs between the different functions of the multifunctional land use system can be identified. The proposed methodology is adaptable to different contexts: if the assumption is taken that all land use functions are equally weighted the framework can be used to analyse policy cases and take decisions on policy options at the European or regional level. However, at the local-scale the framework can also be applied through a participatory approach and the distribution of weights can be rediscussed with local stakeholders. In both cases the proposed system can be used as a tool for discussion among all interested parties.  相似文献   
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Linear and cyclic cyclolinopeptide A (CLA) analogues containing alpha-hydroxymethylleucine (HmL) in positions 1, 4, and 1&4, and alpha-hydroxymethylvaline (HmV) in position 5, were synthesized by the solid-phase peptide strategy and cyclized with the 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide/1-hydroxy-7-azabenzotriazole (EDC/HOAt) reagent. The peptides were examined for their immunosuppressive activity in the lymphocyte proliferation assays (LPA). Only HmL-containing peptides demonstrated at about 25% lower immunosuppressive activity, but they are four times more soluble in water solutions than the native CLA. It seems from the LPA results that peptide [(HmL4)CLA] is the most promising for further studies. This peptide was characterized in solution, at room temperature in CDCl3, and the conformation compared with that observed for CLA in the solid state.  相似文献   
77.
Olmo E 《Genetica》2005,125(2-3):185-203
The chromosome changing rate (i.e. the number of chromosome rearrangements per million years) was studied in 1329 reptile species in order to evaluate the karyological evolutionary trend and the existence of possible correlations between chromosome mutations and some aspects of the evolution of this class. The results obtained highlight the existence of a general direct correlation between chromosome changing rate and number of living species, although different trends can be observed in the different orders and suborders. In turtles, the separation of pleurodires from cryptodires was accompanied by a considerable karyological diversification. Among pleurodires, the evolution of the Chelidae and Pelomedusidae was also characterised by chromosome variation, while in cryptodires a marked karyological homogeneity is observed between and within infraorders. Similarly there is no correlation between changing rate and species number in crocodiles, where the evolution of the families and genera has entailed few chromosome mutations. Chromosome variability was greater in lizards and snakes. In the formers variations in chromosome changing rate accompanied the separation of the infraorders and the evolution of most of the families and of some genera. The origin of snakes has also been accompanied by a marked karyological diversification, while the subsequent evolution of the infraorders and families has entailed a high level of chromosome variability only in colubroids. The karyological evolution in reptiles generally entailed a progressive reduction in chromosome changing rate, albeit with differences in the diverse orders and suborders. This trend seems to be consistent with the “canalization model” as originally proposed by Bickham and Baker in [Bickham, J.W. & R J. Baker, 1979. Bull. Carnegie Mus. Nat. Hist. 13: 70–84.]  However, several inconsistencies have been found excluding that in this class the ultimate goal of chromosome variations was the achievement of a so-called ``optimum karyotype' as suggested by the above-mentioned theory. Other mechanisms could underpin chromosome variability in Reptiles. Among them a genomic composition more or less favourable to promoting chromosome rearrangements and factors favouring the fixation of a mutant karyotype in condition of homozygosis. Turtles and crocodiles would have a genome characterised by large chromosomes and a low level of chromosome compartmentalisation limiting the recombination and the frequency of rearrangements. A low rate of chromosome variability modifying little if at all the gene linkage groups would have favoured a conservative evolutionary strategy. In the course of evolution, lizards and snakes could have achieved a genome characterised by smaller chromosomes and a higher level of compartmentalisation. This would have raised the frequency of recombination and consequently an evolutionary strategy promoting a higher degree of variability and a greater level of speciation.  相似文献   
78.
Statins have been shown to interact with several monocyte/macrophage functions. We tested the effect of pravastatin on transforming growth factor-beta1 (TGF-beta1) production and its possible involvement in scavenger receptors class A (SRA) expression in human THP-1 cells. TGF-beta1s biological activity in THP-1 cell conditioned medium, evaluated by luciferase activity of transfected cell with a TGF-beta responsive promoter, was increased in a dose-dependent manner after incubation with pravastatin (1-20 microM). Pravastatin (1-20 microM) induced a dose-dependent increase in TGF-beta1 mRNA expression and protein production in THP-1 cells. PMA-induced SRA gene and protein expression was suppressed by pravastatin with a mean 3-fold decrease at 10 microM. This last effect was reversed by a mouse monoclonal anti-TGF-beta1 neutralizing antibody. PD98059, a specific inhibitor of MAP kinase cascade, completely reversed pravastatin-induced SRA down-regulation. p44 and p42 isoforms showed a dose-dependent phosphorylation after treatment with pravastatin (1-20 microM) which was inhibited by a mouse monoclonal anti-TGF-beta1 antibody. Our results demonstrate that pravastatin significantly up-regulates TGF-beta1 expression which may be in involved in down-regulation of SRA expression in THP-1 cell cultures. A new pathway for pravastatin effects in atherogenesis can be suggested.  相似文献   
79.
Peroxisome proliferator activated receptors (PPARs) are a class of nuclear receptors involved in lipid and glucidic metabolism, immune regulation, and cell differentiation. Many of their biological activities have been studied by using selective synthetic activators (mainly fibrates and thiazolidinediones) which have been already employed in therapeutic protocols. Both kinds of drugs, however, showed pharmacotoxicological profiles, which cannot be ascribed by any means to receptor activation. To better understand these non-receptorial or extrareceptorial aspects, the effect of different PPAR-ligands on the metabolic status of human HL-60 cell line has been investigated. At this regard, NMR analysis of cell culture supernatants was accomplished in order to monitor modifications at the level of cell metabolism. Cell growth and chemiluminescence assays were employed to verify cell differentiation. Results showed that all the considered PPAR-ligands, although with different potencies and independently from their PPAR binding specificity, induced a significant derangement of the mitochondrial respiratory chain consisting in a strong inhibition of NADH-cytochrome c reductase activity. This derangement has been shown to be strictly correlated to the adaptive metabolic modifications, as evidenced by the increased formation of lactate and acetate, due to the stimulation of anaerobic glycolysis and fatty acid beta-oxidation. It is worthy noting that the mitochondrial dysfunction appeared also linked to the capacity of any given PPAR-ligand to induce cell differentiation. These data could afford an explanation of biochemical and toxicological aspects related to the therapeutic use of synthetic PPAR-ligands and suggest a revision of PPAR pathophysiologic mechanisms.  相似文献   
80.
The ParaHox gene cluster contains three homeobox genes, Gsx, Xlox and Cdx and has been demonstrated to be an evolutionary sister of the Hox gene cluster. Among deuterostomes the three genes are found in the majority of taxa, whereas among protostomes they have so far been isolated only in the phylum Sipuncula.We report the partial sequences of all three ParaHox genes in the polyplacophoran Nuttallochiton mirandus, the first species of the phylum Mollusca where all ParaHox genes have been isolated. This finding has phylogenetic implications for the phylum Mollusca and for its relationships with the other lophotrochozoan taxa.  相似文献   
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