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961.
A full length cDNA encoding the growth hormone receptor (GHR) of Chinese sturgeon was cloned in order to investigate the mechanism of growth hormone in regulating the growth of Chinese sturgeon. The open reading frame of the cloned Chinese sturgeon growth hormone receptor (csGHR) cDNA encodes a trans-membrane protein of 611 amino acids containing all the characteristic motifs of GHR. By sequence alignment, substitutions of amino acid residues highly conserved in other species were identified. Using the CHO cell culture system, the function of csGHR and the biological significance of the amino acid substitution in csGHR were examined. The promoter of serine protease inhibitor 2.1 (Spi2.1) was trans-activated upon stimulation of seabream GH (sbGH) in the csGHR-expressing CHO cells. Furthermore, CHO cells stably expressing csGHR were stimulated to proliferate by sbGH. In agreement with our previous report, Chinese sturgeon growth hormone-binding protein (csGHBP) was detected in the culture medium of CHO cells stably expressing csGHR. Mutation of Asp residue in the ligand binding motif in csGHR to Glu significantly enhanced csGHR’s biological function, whereas mutation of Asp residue to Ala decreased its biological function. The results demonstrated that the cloned csGHR was of full biological function and the csGHBP could be generated through proteolysis of csGHR. These findings might provide new insights into thoroughly understanding the regulatory mechanism of Chinese sturgeon growth. 相似文献
962.
Yonghong Liao Junhua Deng Anding Zhang Mingguang Zhou Yong Hu Huanchun Chen Meilin Jin 《BMC microbiology》2009,9(1):172-8
Background
Actinobacillus pleuropneumoniae is the causative agent of porcine contagious pleuropneumonia, a highly contagious respiratory infection in pigs, and all the 15 serotypes are able to cause disease. Current vaccines including subunit vaccines could not provide satisfactory protection against A. pleuropneumoniae. In this study, the immunoproteomic approach was applied to the analysis of extracellular and outer membrane proteins of A. pleuropneumoniae JL03 serotype 3 for the identification of novel immunogenic proteins for A. pleuropneumoniae. 相似文献963.
964.
Zhen-Xia Sha Shi-Chao Xing Chang-Wei Shao Yong-Sheng Tian Xiao-Lin Liao Song-Lin Chen 《Conservation Genetics》2009,10(6):1799-1801
Ladyfish (Elops saurus Linnaeus) is an economically important marine fish species. 76 microsatellite loci were isolated from an enriched genomic library
of Elops saurus. Twelve of these markers were polymorphic in a test population with alleles per locus ranging from three to nine. The number
of observed, expected heterozygosity and polymorphism information content (PIC) per locus in 20 individuals ranged from 0.2000
to 1.0000, 0.1897–0.8846, 0.1769–0.8476, respectively. One markers significantly deviated from Hardy-Weinberg equilibrium
after Bonferroni correction analysis and there was no significant linkage disequilibrium found between pairs of markers. As
a result, 12 microsatellite markers probably should provide sufficient level of genetic diversity to investigate the fine-scale
population structure, stock management and enhancement, genetic linkage map construction and molecular marker-assisted breeding
in Elops saurus Linnaeus. 相似文献
965.
Gui-Dong Miao Chang-Wei Shao Xiao-Lin Liao Hong-Yu Ma Yong-Sheng Tian Song-Lin Chen 《Conservation Genetics》2009,10(3):701-703
Barfin flounder (Verasper moseri) is a rare fish species in the world. Here, we reported 10 polymorphic microsatellite loci isolated from a dinucleotide-enriched
genomic library of barfin flounder (Verasper moseri). The number of alleles, observed, and expected heterozygosity per locus in a test population ranged from 2 to 6, from 0.3333
to 1.0000, and from 0.4866 to 0.7774, respectively. One locus significantly deviated from Hardy–Weinberg equilibrium after
Bonferroni correction and no significant linkage disequilibrium was found between pairs of loci. Cross-species amplification
of these microsatellite loci in additional five fish species was performed. These polymorphic microsatellite loci would be
useful for investigating genetic population structure and construction of genetic linkage map in Verasper moseri.
Gui-Dong Miao and Chang-Wei Shao Contributed equally to this work. 相似文献
966.
Tianjun Xu Changwei Shao Xiaolin Liao Xiangshan Ji Songlin Chen 《Conservation Genetics》2009,10(3):527-529
From a (GT)13-enriched genomic library of Oplegnathus fasciatus, 14 polymorphic microsatellite were isolated and characterized in a test population with alleles ranging from two to nine,
the observed and expected heterozygosities from 0.0000 to 1.0000, and from 0.1726 to 0.8507, respectively. Five loci deviated
from the Hardy–Weinberg equilibrium, and linkage disequilibrium between two loci was significant. Two loci were also polymorphic
in Pagrosomus major assessed for cross-species amplification. These polymorphic microsatellites will be useful for genetic diversity analysis
and molecule-assisted breeding for O. fasciatus.
Changwei Shao contributed equally. 相似文献
967.
Hao Ding Changwei Shao Xiaolin Liao Genbo Xu Xiangshan Ji Songlin Chen 《Conservation Genetics》2009,10(3):611-614
In the present study, 10 polymorphic microsatellite DNA loci from Atlantic halibut (Hippoglossus hippoglossus) were isolated and characterized. The number of alleles for these loci ranged from 2 to 4 in tested 24 individuals. Observed
and expected heterozygosities per locus varied from 0.21 to 0.70 and from 0.31 to 0.65, respectively. Most of these 10 microsatellite
loci were successfully amplified and showed polymorphic in five related species. These loci will be useful for the assessment
of genetic diversity and population structure of Atlantic halibut.
H. Ding and C. Shao contributed equally to this work. 相似文献
968.
969.
970.
A nanobiocomposite film consisted of polypyrrole (PPy), functionalized multiwalled carbon nanotubes (cMWNTs), and glucose oxidase (GOx) were electrochemically synthesized by electrooxidation of 0.1M pyrrole in aqueous solution containing appropriate amounts of cMWNTs and GOx. Potentiostatic growth profiles indicate that the anionic cMWNTs is incorporated within the growing PPy-cMWNTs nanocomposite for maintaining its electrical neutrality. The morphology of the PPy-cMWNTs nanocomposite was characterized by scanning electron microscopy (SEM). The PPy-cMWNTs nanocomposite was deposited homogeneously onto glassy carbon electrode. The amperometric responses vary proportionately to the concentration of hydrogen peroxide at the PPy-cMWNTs nanocomposite modified electrode at an operating potential of 0.7V versus Ag/AgCl (3M). The results indicate that the electroanalytical PPy-cMWNTs-GOx nanobiocomposite film was highly sensitive and suitable for glucose biosensor based on GOx function. The GOx concentration within the PPy-cMWNTs-GOx nanobiocomposite and the film thickness are crucial for the performance of the glucose biosensor. The amperometric responses of the optimized PPy-cMWNTs-GOx glucose biosensor (1.5 mgmL(-1) GOx, 141 mCcm(-2) total charge) displayed a sensitivity of 95 nAmM(-1), a linear range up to 4mM, and a response time of about 8s. 相似文献