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1.
N. Cappetti A. Naddeo G. F. Solitro 《Computer methods in biomechanics and biomedical engineering》2016,19(12):1278-1285
The aim of this work is to show a quick and simple procedure able to identify the geometrical parameters of the intervertebral disc that strongly affect the behavior of the FEM model. First, we allocated a selection criterion for the minimum number of geometrical parameters that describe, with a good degree of approximation, a healthy human vertebra. Next, we carried out a sensitivity analysis using the ‘Taguchi orthogonal array’ to arrive at a quick identification of the parameters that strongly affect the behavior of the Fem model. 相似文献
2.
α-Glucosidase is a catabolic enzyme that regulates the body’s plasma glucose levels by providing energy sources to maintain healthy functioning. 2-Amino-thiadiazole (1–13) and 2-amino-thiadiazole based Schiff bases (14–22) were synthesized, characterized by 1H NMR and HREI-MS and screened for α-glucosidase inhibitory activity. All twenty-two (22) analogs exhibit varied degree of α-glucosidase inhibitory potential with IC50 values ranging between 2.30 ± 0.1 to 38.30 ± 0.7 μM, when compare with standard drug acarbose having IC50 value of 39.60 ± 0.70 μM. Among the series eight derivatives 1, 2, 6, 7, 14, 17, 19 and 20 showed outstanding α-glucosidase inhibitory potential with IC50 values of 3.30 ± 0.1, 5.80 ± 0.2, 2.30 ± 0.1, 2.70 ± 0.1, 2.30 ± 0.1, 5.50 ± 0.1, 4.70 ± 0.2, and 5.50 ± 0.2 μM respectively, which is many fold better than the standard drug acarbose. The remaining analogs showed good to excellent α-glucosidase inhibition. Structure activity relationship has been established for all compounds. The binding interactions of these compounds were confirmed through molecular docking. 相似文献
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5.
《Bioorganic & medicinal chemistry》2014,22(1):141-147
A series of new sulfonamides was prepared starting from 2-oxo-N′-(4-sulfamoylphenyl)-propanehydrazonoyl chloride, a sulfanilamide derivative, which was reacted with aroylhydrazides, amines, or thiols. A library of derivatives incorporating aroylhydrazone, [1,2,4]triazolo[3,4-b][1,3,4]thiadiazinyl- or 2-(cyanophenyl-methylene)-1,3,4-thiadiazol-3(2H)-yl moieties was thus synthesized. The new compounds were investigated as inhibitors of four α-carbonic anhydrases (CAs, EC 4.2.1.1), the human (h) isoforms hCA I and II, and the bacterial ones recently isolated from the extremophilic bacteria Sulfurihydrogenibium yellostonense (SspCA) and Sulfurihydrogenibium azorense (SazCA). Low nanomolar activity was observed against hCA II (KIs of 0.56–17.1 nM) whereas hCA I was less inhibited by these compounds (KIs of 86.4 nM–32.8 μM). The bacterial CAs were also effectively inhibited by these derivatives (KIs in the range of 0.77–234 nM against SazCA, and of 6.2–89.1 against SspCA, respectively), with several low nanomolar/subnanomolar inhibitors detected against both of them. As SspCA and SazCA are among the most thermostable and catalytically active CAs, it is of interest to find modulators of their activity for potential biotechnologic applications. 相似文献
6.
《Bioorganic & medicinal chemistry》2014,22(22):6324-6332
The blood coagulation cascade represents an attractive target for antithrombotic drug development, and recent studies have attempted to identify oral anticoagulants with inhibitory activity for enzymes in this cascade, with particular attention focused on thrombin and factor Xa (fXa) as typical targets. We previously described the discovery of the orally active fXa inhibitor darexaban (1) and reported a unique profile that compound 1 rapidly transformed into glucuronide YM-222714 (2) after oral administration. Here, we propose a novel strategy towards the discovery of an orally active anticoagulant that is based on the bioconversion of a non-amidine inhibitor into the corresponding conjugate to boost ex vivo anticoagulant activity via an increase in hydrophilicity. Computational molecular modeling was utilized to select a template scaffold and design a substitution point to install a potential functional group for conjugation. This strategy led to the identification of the phenol-derived fXa inhibitor ASP8102 (14), which demonstrated highly potent anticoagulant activity after biotransformation into the corresponding glucuronide (16) via oral dosing. 相似文献
7.
Dominic Moran 《Biodiversity and Conservation》1994,3(8):663-684
The financial returns to Kenyan tourism demonstrate the importance of the country's tourist potential to its economic development. Protected areas and their inhabitants are the principal focus of the tourist industry, the nations's main foreign exchange earner, and a source of wonder and value for a global population of non-users. It might be expected that such assets would be accorded some degree of security with sufficient funding to safeguard current and potential economic benefits. Yet park use is haphazard, and there is frequently little coincidence between those that benefit and those that pay for the continued existence of such areas. Growing economic and demographic pressures which threaten to swamp protected areas only emphasize the implicit subsidy currently paid by Kenyans to support conservation for the benefit of the world at large. In this climate the case for conservation depends on the measurement and capture of economic benefits. Using a contingent valuation survey of expressed preference this study estimates the consumer surplus attached to current non-consumptive use of protected areas by foreign visitors at some $450 million per annum. This sum alone is more than double the best available estimate of opportunity cost and appears to justify current resource use. The estimate is additional to current financial returns from tourism and makes no allowance for other direct and indirect benefits and potential returns from consumptive uses. Measured consumer surplus contains some margin of willingness to pay that could be captured through the current fee structure. Moreover, park fees represent the most accessible market mechanism to finance revenue sharing and additional park investment before potential recourse to emerging global market institutions. 相似文献
8.
Hiroyuki Akita 《Biocatalysis and Biotransformation》1996,13(3):141-156
Water-insoluble compounds can be substrates for enzymatic reactions when lipases are immobilized properly and suitable organic solvents are used. In this review, three type of lipase immobilization method and their application to the asymmetric syntheses of complex molecules are described. Lipases immobilized with Celite or synthetic prepolymers such as urethane prepolymer and photo-crosslinkable resin prepolymer have been applied for the kinetic resolution of many kinds of water-insoluble substrate.
Phospholipid-lipase aggregates with ether linkages are novel and have been found to function effectively as immobilized lipases in asymmetric hydrolysis or esterification reactions in water-saturated organic solvent. The phospholipid-lipase aggregates are considered to have a stacked bilayer based on X-ray diffraction analysis structure of the lipid in the crystalline phase. 相似文献
Phospholipid-lipase aggregates with ether linkages are novel and have been found to function effectively as immobilized lipases in asymmetric hydrolysis or esterification reactions in water-saturated organic solvent. The phospholipid-lipase aggregates are considered to have a stacked bilayer based on X-ray diffraction analysis structure of the lipid in the crystalline phase. 相似文献
9.
Abstract. A major objection to the convenient sampling of Chenopodiacean bladders by brushing in aqueous solutions is the suspected leakage of ions from the leaf blade. To overcome this problem, a new method of sampling bladder hair is described, which also achieves rapid and quantitative separation and, at the same time, yields bladder samples of undoubtedly high purity. Leakage is stopped by the aid of liquid nitrogen. Comparison of this method to removal of bladders by brushing in aquenous solutions effectively confirm the validity of the customary method beyond dispute. 相似文献
10.
Reza Modarres 《Biometrical journal. Biometrische Zeitschrift》1993,35(7):785-790
The likelihood ratio test for testing equality of vgE;2 correlated variables is developed. In general, evaluation of the test statistic involves the iterative optimization of a likelihood function with 1 + v(v – 1)/2 parameters. The explicit form of the test statistic is derived in the bivariate case, and an iterative algorithm for determining the maximum likelihood estimates is suggested. A limited Monte Carlo study determines the behavior of the proposed procedure under the null hypothesis and variety of parameter values. 相似文献