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This paper puts forward a framework for probabilistic and holistic cost-effectiveness analysis to provide support in selecting the least-cost set of measures to reach a multidimensional environmental objective. Following the principles of ecosystem-based management, the framework includes a flexible methodology for deriving and populating criteria for effectiveness and costs and analyzing complex ecological-economic trade-offs under uncertainty. The framework is applied in the development of the Finnish Programme of Measures (PoM) for reaching the targets of the EU Marine Strategy Framework Directive (MSFD). The numerical results demonstrate that substantial cost savings can be realized from careful consideration of the costs and multiple effects of management measures. If adopted, the proposed PoM would yield improvements in the state of the Baltic Sea, but the overall objective of the MSFD would not be reached by the target year of 2020; for various environmental and administrative reasons, it would take longer for most measures to take full effect.  相似文献   
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The binding characteristics of [3H]-imipramine in slide mounted tissue sections of rat forebrain have been studied to ascertain the optimal binding conditions for labeling the sites prior to autoradiographic localization. The conditions for the experiments and the kinetics of the imipramine binding correspond reasonably well with those used in membrane preparations to initially define the imipramine binding site. Subsequent labeling of sections, using these parameters, allowed the autoradiographic localization of high concentrations of imipramine binding sites in such areas as the cerebral cortex, striatum, and several limbic and visual system structures. In addition, there was a marked overlap between regions demonstrating imipramine binding and areas known to be innervated by serotonergic neurons. This study outlines the potential sites of action of imipramine in the brain and defines areas for future investigations which attempt to localize brain regions involved in the etiology of depression and areas involved in the side effects of antidepressant drug therapy.  相似文献   
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Autocrine activation of the epidermal growth factor (EGF) receptor on keratinocytes has been recognized as an important growth regulatory mechanism involved in epithelial homeostasis, and, possibly, hyperproliferative diseases. Insulin-like growth factor (IGF)-1 and insulin have been shown to be paracrine keratinocyte mitogens that bind to the type I IGF receptor which is expressed on actively proliferating keratinocytes in situ. In this report, we demonstrate that IGF-1/insulin induced production of keratinocyte-derived autocrine growth factors that bind to the EGF receptor. Increased steady-state mRNA levels for transforming growth factor alpha (TGF-α) and for amphiregulin (AR) were observed upon incubation of keratinocytes with mitogenic concentrations of IGF-1. IGF-1 also induced production and secretion of TGF-α and AR proteins as detected by immunoassays. An EGF receptor antagonistic monoclonal antibody abolished the mitogenic effect of IGF-1 on cultured keratinocytes. These results suggest that stimulation of keratinocyte growth by IGF-1 requires activation of an EGF receptor-mediated autocrine loop. © 1995 Wiley-Liss, Inc.  相似文献   
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During the growth cycle of normal fibroblasts and of fibroblasts deficient in glucose-6-phosphate dehydrogenase activity, the concentration of 5-phosphoribosyl-1-pyrophosphate and of Pi, as well as the activity of 5-phosphoribosyl-1-pyrophosphate synthetase, decreased to stable values in confluent cultures. A high degree of correlation (0.89 and 0.91 for two normal and 0.69 for one glucose-6-phosphate dehydrogenase-deficient cell strain, respectively) was shown between intracellular Pi and 5-phosphoribosyl-1-pyrophosphate concentrations under varying culture and incubation conditions. 5-phosphoribosyl-1-pyrophosphate concentrations were elevated in normal fibroblasts incubated with methylene blue only if intracellular Pi levels were high. Neither methylene blue nor 6-aminonicotinamide, singly, affected intracellular Pi concentrations. However, when normal cells were pretreated with 6-aminonicotinamide and then with methylene blue, intracellular Pi decreased, 5-phosphoribosyl-1-pyrophosphate was depleted, and its rate of generation decreased. Under similar conditions, glucose-6-phosphate dehydrogenase-deficient fibroblasts maintained unaltered Pi levels, and 5-phosphoribosyl-1-pyrophosphate concentration and generation were slightly increased. The decrease in intracellular Pi in normal cells after the combined treatment was commensurate with an accumulation of 6-phosphogluconate, which did not take place in mutant cells. The changes in 5-phosphoribosyl-1-pyrophosphate synthesis, whether due to the stage of growth or various experimental manipulations, were always concordant with changes in intracellular Pi level. The regulatory role of Pi is consistent with the known enzymic properties of 5-phosphoribosyl-1-pyrophosphate synthetase.  相似文献   
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Abstract The outer membrane (OM) structure of Nitrosospira sp. X101 was studied by different electron microscopic techniques and SDS-PAGE. A crystalline outer membrane protein was visible in freeze-etched cells, occasionally seen also in the thin sectioned cells, but was difficult to see in a negatively-stained preparation. The lattice probably consists of large globular protein subunits with a hexagonal arrangement. The molecular weights of the major proteins in the cell envelope are 35 kDa, 40 kDa and 42 kDa.  相似文献   
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Aim We investigated the phylogeography, geographical variation in leaf morphology, freezing tolerance and climatic niches of two widespread evergreen sister oak species (Quercus) in the series Virentes. Location South‐eastern USA, Mexico and Central America. Methods Nuclear microsatellites and non‐recombining nuclear and chloroplast DNA sequences were obtained from trees throughout the range of two sister lineages of live oaks, represented by Quercus virginiana in the temperate zone and Q. oleoides in the tropics. Divergence times were estimated for the two major geographical and genetic breaks. Differentiation in leaf morphology, analysed from field specimens, was compared with the molecular data. Freezing sensitivities of Q. virginiana and Q. oleoides populations were assessed in common garden experiments. Results The geographical break between Q. virginiana and Q. oleoides was associated with strong genetic differentiation of possible early Pleistocene origin and with differentiation in freezing sensitivity, climatic envelopes and leaf morphology. A second important geographical and genetic break within Q. oleoides between Costa Rica and the rest of Central America showed a mid‐Pleistocene divergence time and no differentiation in leaf morphology. Population genetic differentiation was greater but genetic diversity was lower within the temperate Q. virginiana than within the tropical Q. oleoides, and genetic breaks largely corresponded to breaks in leaf morphology. Main conclusions Two major breaks, one between Mexico and the USA at the boundary of the two species, and a more recent one within Q. oleoides between Honduras and Costa Rica, implicate climatic changes as potential causes. The latter break may be associated with the formation of the Cordillera de Guanacaste, which was followed by seasonal changes in precipitation. In the former case, an ‘out of the tropics’ scenario is hypothesized, in which the acquisition of freezing tolerance in Q. virginiana permitted colonization of and expansion in the temperate zone, while differences in climatic tolerances between the species limited secondary contact. More pronounced Pleistocene changes in climate and sea level in the south‐eastern USA relative to coastal Mexico and Central America may explain the greater population differentiation within temperate Q. virginiana and greater genetic diversity in tropical Q. oleoides. These patterns are predicted to hold for other taxa that span temperate and tropical zones of North and Central America.  相似文献   
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A simple and reliable method for analyzing the concentrations of clozapine and its biologically active metabolite, norclozapine, in human serum or plasma has been developed. This method is based on reversed-phase high-performance liquid chromatography (HPLC) with automated solid-phase extraction (SPE). For HPLC analysis, samples and standards are prepared with an ASPEC automatic sample preparator using 100 mg Bond-Elut C18 SPE columns. The HPLC assay is an isocratic method with a mobile phase of acetonitrile-methanol-10 mM dipotassium hydrogenphosphate, pH 3.7 (30:2:100, v/v/v) at a flow-rate of 1.5 ml/min with a C18 reversed-phase column. Detection is performed with a diode array detector set at 220 nm and with peak purity analyses at 210–365 nm. The absolute recovery varied from 85 and 95%. The intra-assay coefficients of variation (C.V.s) were from 4.2 and 8.0% and the inter-assay C.V.s were from 1.1. to 9.3% at therapeutic drug concentrations. The detection limit is 15 nmol/l. The method has been developed for use in a clinical laboratory for therapeutic drug monitoring.  相似文献   
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