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31.
Starch-binding domains in the post-genome era 总被引:1,自引:1,他引:0
Starch belongs to the most abundant biopolymers on Earth. As a source of energy, starch is degraded by a large number of various
amylolytic enzymes. However, only about 10% of them are capable of binding and degrading raw starch. These enzymes usually
possess a distinct sequence-structural module, the so-called starchbinding domain (SBD). In general, all carbohydrate-binding
modules (CBMs) have been classified into the CBM families. In this sequence-based classification the individual types of SBDs
have been placed into seven CBM families: CBM20, CBM21, CBM25, CBM26, CBM34, CBM41 and CBM45. The family CBM20, known also
as a classical C-terminal SBD of microbial amylases, is the most thoroughly studied. The three-dimensional structures have
already been determined by X-ray crystallography or nuclear magnetic resonance for SBDs from five CBM families (20, 25, 26,
34 and 41), and the structure of the CBM21 has been modelled. Despite differences among the amino acid sequences, the fold
of a distorted β-barrel seems to be conserved together with a similar way of substrate binding (mainly stacking interactions
between aromatic residues and glucose rings). SBDs have recently been discovered in many non-amylolytic proteins. These may,
for example, have regulatory functions in starch metabolism in plants or glycogen metabolism in mammals. SBDs have also found
practical uses.
Received 25 May 2006; received after revision 26 June 2006; accepted 3 August 2006 相似文献
32.
33.
RNA polymerase is poised for activation across the genome 总被引:2,自引:0,他引:2
Muse GW Gilchrist DA Nechaev S Shah R Parker JS Grissom SF Zeitlinger J Adelman K 《Nature genetics》2007,39(12):1507-1511
34.
35.
Natural variation for sulfate content in Arabidopsis thaliana is highly controlled by APR2 总被引:2,自引:0,他引:2
Loudet O Saliba-Colombani V Camilleri C Calenge F Gaudon V Koprivova A North KA Kopriva S Daniel-Vedele F 《Nature genetics》2007,39(7):896-900
Most agronomic traits of importance, whether physiological (such as nutrient use efficiency) or developmental (such as flowering time), are controlled simultaneously by multiple genes and their interactions with the environment. Here, we show that variation in sulfate content between wild Arabidopsis thaliana accessions Bay-0 and Shahdara is controlled by a major quantitative trait locus that results in a strong interaction with nitrogen availability in the soil. Combining genetic and biochemical results and using a candidate gene approach, we have cloned the underlying gene, showing how a single-amino acid substitution in a key enzyme of the assimilatory sulfate reduction pathway, adenosine 5'-phosphosulfate reductase, is responsible for a decrease in enzyme activity, leading to sulfate accumulation in the plant. This work illustrates the potential of natural variation as a source of new alleles of known genes, which can aid in the study of gene function and metabolic pathway regulation. Our new insights on sulfate assimilation may have an impact on sulfur fertilizer use and stress defense improvement. 相似文献
36.
Gout AM;ADPKD Gene Variant Consortium Ravine D Harris PC Rossetti S Peters D Breuning M Henske EP Koizumi A Inoue S Shimizu Y Thongnoppakhun W Yenchitsomanus PT Deltas C Sandford R Torra R Turco AE Jeffery S Fontes M Somlo S Furu LM Smulders YM Mercier B Ferec C Burtey S Pei Y Kalaydjieva L Bogdanova N McCluskey M Geon LJ Wouters CH Reiterova J Stekrová J San Millan JL Aguiari G Del Senno L 《Nature genetics》2007,39(4):427-428
37.
Dreschers S Dumitru CA Adams C Gulbins E 《Cellular and molecular life sciences : CMLS》2007,64(2):181-191
Rhinoviruses, which cause common cold, belong to the Picornaviridae family, small non-enveloped viruses (diameter 15-30 nm) containing a single-stranded RNA genome (about 7 kb). Over 100 different rhinoviral serotypes have been identified thus far, establishing rhinoviruses as the most diverse group of Picornaviridae. Based on receptor binding properties, rhinoviruses are divided into two classes: the major group binding to intracellular adhesion molecule-1 and the minor group binding to the very low density lipoprotein receptors. Interactions between virus and the receptor molecules cause a conformational change in the capsid, which is a prerequisite for viral uptake. Rhinoviruses trigger a chemokine response upon infection that may lead to exacerbation of the symptoms of common cold, i.e. asthma and inflammation. The following review aims to summarize the knowledge about rhinoviral infections and discusses therapeutical approaches against this almost perfectly adapted pathogen. 相似文献
38.
39.
S. K. MISHRA Shouyang WANG K. K. LAI 《系统科学与复杂性》2007,20(3):344-349
In this paper, we introduce a new class of generalized convex function, namely, a-pseudounivex function, by combining the concepts of pseudo-univex and α-invex functions. Further, we establish some relationships between vector variational-like inequality problems and vector optimization problems under the assumptions of α-pseudo-univex functions. Results obtained in this paper present a refinement and improvement of previously known results. 相似文献
40.