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91.
Hsin-Shih Wang Hsien-Ming Wu Bi-Hwa Cheng Chih-Feng Yen Pi-Yueh Chang Angel Chao Yun-Shien Lee Hsien-Da Huang Tzu-Hao Wang 《PloS one》2012,7(11)
Endometriosis is determined by genetic factors, and the prevalence of genetic polymorphisms varies greatly depending on the ethnic group studied. The objective of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) of 9 genes involved in estrogen biosynthesis and metabolism and the risks of endometriosis. Three hundred patients with endometriosis and 337 non-endometriotic controls were recruited. Thirty four non-synonymous SNPs, which change amino acid residues, were analyzed using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). The functions of SNP-resulted amino acid changes were analyzed using multiple web-accessible databases and phosphorylation predicting algorithms. Among the 34 NCBI-listed SNPs, 22 did not exhibit polymorphism in this study of more than 600 Taiwanese Chinese women. However, homozygous and heterozygous mutants of 4 SNPs - rs6165 (genotype GG+GA, 307Ala/Ala+307Ala/Thr) of FSHR, rs 6166 (genotype GG+GA, 680Ser/Asn+680Ser/Ser) of FSHR, rs2066479 (genotype AA+AG, 289Ser/Ser+289Ser/Gly) of HSD17B3 and rs700519 (genotype TT+TC, 264Cys/Cys+264Cys/Arg) of CYP19, alone or in combination, were significantly associated with decreased risks of endometriosis. Bioinformatics results identified 307Thr of FSHR to be a site for O-linked glycosylation, 680Ser of FSHR a phosphorylated site by protein kinase B, and 289Ser of HSD17B3 a phosphorylated site by protein kinase B or ribosomal protein S6 kinase 1. Results of this study suggest that non-synonymous polymorphisms of FSHR, HSD17B3 and CYP19 genes may modulate the risk of endometriosis in Taiwanese Chinese women. Identification of the endometrosis-preferential non-synonymous SNPs and the conformational changes in those proteins may pave the way for the development of more disease-specific drugs. 相似文献
92.
C. S. Lin M. C. Tseng P. I. Hong W. C. Chang 《In vitro cellular & developmental biology. Plant》2006,42(4):331-335
Summary Inflorescence proliferation is a plant tissue culture technique that, can be used to obtain in vitro inflorescences year-round without the intervening development of vegetative organs. In this study, we used albino mutant
inflorescences of Dendrocalamus latiflorus as the original explant material to investigate, the effect of plant growth regulators on long-term inflorescence proliferation.
The albino inflorescences proliferated on solidified Murashige and Skoog (MS) basal medium supplemented with thidiazuron (TDZ),
and the optimal concentration for successful long-term inflorescence proliferation was 0.45 μM TDZ. A combination of α-naphthaleneacetic acid (NAA) with 0.45 μM TDZ inhibited the inflorescence proliferation. Inflorescences cultured on a TDZ-free medium supplemented with 26.82 μM NAA rooted in 21 d, vegetative shoots formed by 42 d and, in one case, flowering occurred after 63 d. The auxins 2,4-dichlorophenoxyacetic
acid (2,4-D, 4.52 μM) and pieloram (4.14 μM) induced shoot formation. The protocol described can be used to produce large numbers of mutant inflorescences within a relatively
short period of time. 相似文献
93.
l-Glutamic acid actively loaded into resealed brain synaptic membrane vesicles was rapidly released into the incubation medium following the introduction of KCl and CaCl2, or nigericin, or veratridine into the external medium. The KCl-induced release was enhanced by the presence of low (0.1 mM), extravesicular [Ca2+]. Neither the KCl-induced nor the veratridine-stimulated l-glutamate efflux were carrier-mediated processes. Finally, the KCl-stimulated l-glutamate efflux was dependent on the ratio of intra- to extravesicular [K+]. The observations described in this study were indicative of depolarization-induced l-glutamate release from isolated synaptic plasma membrane vesicles. 相似文献
94.
The effect of T-independent (TIA) and T-dependent (IDA) antigens on the surface Ig of 24-hr cultured rabbit spleen cells was investigated by two techniques: the proportion of cells bearing surface Ig was determined by direct rosette formation with anti-light chain allotype-coated erythrocytes; the total amount of surface Ig was estimated by labeling the cells with anti-allotype 125I-labeled Fab fragments. The addition of TIA resulted in the maintenance of the proportion of Ig-bearing cells almost to the initial level, an effect which could not be obtained with any of the TDA tested. The same type of effect was observed when the total amount of surface Ig was measured, i.e., there was a slight reduction (about 24%) in the amount of surface Ig in cultures to which TIAs were added and an almost sixfold reduction (about 70%) in cultures to which TDA, Con A, or no antigen was added. Some but not all of the TIA were able to induce [3H]TdR incorporation in 3-day spleen-cell cultures. We concluded that the common feature of TIA is the ability to stimulate the turnover of B-cell surface Ig, a feature that can be used for an easy screening of TIA. 相似文献
95.
Ryan Wilcox Bryan E Welm Jeffrey T Chang Evan Johnson Avrum Spira Stefanie S Jeffrey Andrea H Bild 《Molecular systems biology》2011,7(1)
Identifying the best drug for each cancer patient requires an efficient individualized strategy. We present MATCH (M erging genomic and pharmacologic A nalyses for T herapy CH oice), an approach using public genomic resources and drug testing of fresh tumor samples to link drugs to patients. Valproic acid (VPA) is highlighted as a proof‐of‐principle. In order to predict specific tumor types with high probability of drug sensitivity, we create drug response signatures using publically available gene expression data and assess sensitivity in a data set of >40 cancer types. Next, we evaluate drug sensitivity in matched tumor and normal tissue and exclude cancer types that are no more sensitive than normal tissue. From these analyses, breast tumors are predicted to be sensitive to VPA. A meta‐analysis across breast cancer data sets shows that aggressive subtypes are most likely to be sensitive to VPA, but all subtypes have sensitive tumors. MATCH predictions correlate significantly with growth inhibition in cancer cell lines and three‐dimensional cultures of fresh tumor samples. MATCH accurately predicts reduction in tumor growth rate following VPA treatment in patient tumor xenografts. MATCH uses genomic analysis with in vitro testing of patient tumors to select optimal drug regimens before clinical trial initiation. 相似文献
96.
97.
In this study, a two-level full factorial design was used to identify the effects of the interactions between compositions in an N-isopropylacrylamide (NIPAM) gel dosimeter involving the following variables: (A) gelatin, (B) NIPAM, (C) the crosslinker N, N′-methylene-bis-acrylamide (Bis), and (D) the antioxidant tetrakis (hydroxymethyl) phosphonium chloride (THPC). The dose range was from 0 Gy to 5 Gy. Optical computed tomography was used to scan the polymer gel dosimeter. Each component was set to two levels for all four variables, including (A) 4% and 6%, (B) 4% and 6%, (C) 2% and 4%, as well as (D) 5 and 15 mM. Response surface methodology and a central composite design were adopted for the quantitative investigation of the respective interaction effects on the dose response curve of the gel. The results showed that the contributions of the interaction effects, i.e., AB (6.22%), AC (8.38%), AD (7.74%), BC (9.44%), ABC (18.24%), BCD (12.66%), and ABCD (13.4%), were greater than those of the four main effects, accounting for over 76.08% of the total variability. These results also indicated that the NIPAM gel recipe with the highest sensitivity was at 40%C (mass fraction of Bis). 相似文献
98.
Corinna Richter Ron L. Dy Rebecca E. McKenzie Bridget N.J. Watson Corinda Taylor James T. Chang Matthew B. McNeil Raymond H.J. Staals Peter C. Fineran 《Nucleic acids research》2014,42(13):8516-8526
Clustered regularly interspaced short palindromic repeats (CRISPR), in combination with CRISPR associated (cas) genes, constitute CRISPR-Cas bacterial adaptive immune systems. To generate immunity, these systems acquire short sequences of nucleic acids from foreign invaders and incorporate these into their CRISPR arrays as spacers. This adaptation process is the least characterized step in CRISPR-Cas immunity. Here, we used Pectobacterium atrosepticum to investigate adaptation in Type I-F CRISPR-Cas systems. Pre-existing spacers that matched plasmids stimulated hyperactive primed acquisition and resulted in the incorporation of up to nine new spacers across all three native CRISPR arrays. Endogenous expression of the cas genes was sufficient, yet required, for priming. The new spacers inhibited conjugation and transformation, and interference was enhanced with increasing numbers of new spacers. We analyzed ∼350 new spacers acquired in priming events and identified a 5′-protospacer-GG-3′ protospacer adjacent motif. In contrast to priming in Type I-E systems, new spacers matched either plasmid strand and a biased distribution, including clustering near the primed protospacer, suggested a bi-directional translocation model for the Cas1:Cas2–3 adaptation machinery. Taken together these results indicate priming adaptation occurs in different CRISPR-Cas systems, that it can be highly active in wild-type strains and that the underlying mechanisms vary. 相似文献
99.
Chien Teh Chen Cheng Chang Li Ching Huei Kao 《Journal of Plant Growth Regulation》1991,10(1-4):201-205
Leaf senescence of a chlorophylldeficient rice mutant (LT-8) was investigated. At 10 days after planting, the chlorophyll level in the third leaves of rice seedlings of the mutant was about one half that of normal leaves (Norin no. 8), whereas no difference in the protein level could be detected in the two genotypes. The protein level in leaves decreased with increasing age, and no significant difference could be detected during senescence in the two genotypes. Chlorophyll level in the normal leaves also decreased with increasing age. However, the chlorophyll level in the mutant leaves began to decrease only after more than 60% of the initial protein had been degraded. The pattern of ethylene production in the normal leaves was, in general, similar to that in the mutant leaves. Ethylene production first decreased with age, increased to a maximum at day 18, and decreased thereafter. Both spermidine and spermine levels in the leaves of the two genotypes decreased with increasing age. The pattern of the putrescine level in the normal leaves behaved somewhat similar to that in the mutant leaves. However, during the course of senescence, the putrescine level in the mutant leaves was always higher than that in the normal leaves. The possible relationship between endogenous polyamine levels and ethylene production is discussed. 相似文献
100.