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21.
Schwarzenbacher R Jaroszewski L von Delft F Abdubek P Ambing E Biorac T Brinen LS Canaves JM Cambell J Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Eshagi S Floyd R Godzik A Grittini C Grzechnik SK Hampton E Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Ouyang J Page R Quijano K Robb A Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Xu Q Hodgson KO Wooley J Wilson IA 《Proteins》2004,55(3):759-763
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Astola A Calduch-Giner JA Ortiz M Pérez-Sánchez J Valdivia MM 《Marine biotechnology (New York, N.Y.)》2004,6(5):411-418
Somatolactin (SL) is a pituitary hormone belonging to the growth hormone–prolactin family and is produced in the intermediate lobe of teleosts. The SL gene was isolated from a sea bream genomic library and found to be composed of 5 exons distributed within a 9-kb length of DNA. Sequence analysis of the proximal promoter region showed the presence of a classical TATA box located 59 bp upstream from the initial start ATG codon, 5 consensus sequences corresponding to the Pit-1 binding element, and a putative CREB site. In CHO cells cotransfected with the DNA from 2 plasmids, one encoding sea bream Pit-1 under Rous sarcoma virus long terminal repeat regulation and one encoding the SL promoter driving the expression of luciferase, Pit-1 was found to enhance the expression of luciferase. Only one Pit-1 binding site was necessary for enhancement. Analysis by immunoblots of in vitro culture of pituitaries of Sparus aurata showed that several agents, including estradiol, verapamil, and phorbol myristate acetate, had different inhibitory effects on SL and growth hormone released to the culture medium. 相似文献
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Rosell A Valencia E Parés X Fita I Farrés J Ochoa WF 《Journal of molecular biology》2003,330(1):75-85
The amphibian enzyme ADH8, previously named class IV-like, is the only known vertebrate alcohol dehydrogenase (ADH) with specificity towards NADP(H). The three-dimensional structures of ADH8 and of the binary complex ADH8-NADP(+) have been now determined and refined to resolutions of 2.2A and 1.8A, respectively. The coenzyme and substrate specificity of ADH8, that has 50-65% sequence identity with vertebrate NAD(H)-dependent ADHs, suggest a role in aldehyde reduction probably as a retinal reductase. The large volume of the substrate-binding pocket can explain both the high catalytic efficiency of ADH8 with retinoids and the high K(m) value for ethanol. Preference of NADP(H) appears to be achieved by the presence in ADH8 of the triad Gly223-Thr224-His225 and the recruitment of conserved Lys228, which define a binding pocket for the terminal phosphate group of the cofactor. NADP(H) binds to ADH8 in an extended conformation that superimposes well with the NAD(H) molecules found in NAD(H)-dependent ADH complexes. No additional reshaping of the dinucleotide-binding site is observed which explains why NAD(H) can also be used as a cofactor by ADH8. The structural features support the classification of ADH8 as an independent ADH class. 相似文献
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Can a Place of Origin of the Main Cystic Fibrosis Mutations Be Identified? 总被引:3,自引:0,他引:3 下载免费PDF全文
Eva Mateu Francesc Calafell Maria Dolors Ramos Teresa Casals Jaume Bertranpetit 《American journal of human genetics》2002,70(1):257-264
The genetic background of the mutations that most often cause cystic fibrosis (CF) is different from that of non-CF chromosomes in populations of European origin. It is not known whether these haplotype backgrounds could be found at high frequencies in populations in which CF is, at present, not common; such populations would be candidates for the place of origin of CF mutations. An analysis of haplotypes of CF transmembrane conductance regulator, together with their variation in specific CF chromosomes, in a worldwide survey of normal chromosomes shows (1) a very low frequency or absence of the most common CF haplotypes in all populations analyzed and (2) a strong genetic variability and divergence, among various populations, of the chromosomes that carry disease-causing mutations. The depth of the gene genealogy associated with disease-causing mutations may be greater than that of the evolutionary process that gave rise to present-day human populations. The concept of "population of origin" lacks either spatial or temporal meaning for mutations that are likely to have been present in Europeans before the ethnogenesis of present populations; subsequent population processes may have erased the traces of their geographic origin. 相似文献
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Calduch-Giner JA Mingarro M Vega-Rubín de Celis S Boujard D Pérez-Sánchez J 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2003,136(1):1-13
The full-length growth hormone receptor (GHR) of gilthead sea bream (Sparus aurata) was cloned and sequenced by RT-PCR and rapid amplification of 5'and 3'ends. The open reading frame codes for a mature 609 amino acid protein with a hydrophobic transmembrane region and all the characteristic motifs of GHRs. Sequence analysis revealed a 96 and 76% of amino acid identity with black sea bream (Acanthopagrus schlegeli) and turbot (Scophthalmus maximus) GHRs, respectively, but this amino acid identity decreases up to 52% for goldfish (Carassius auratus) GHR. By means of real-time PCR assays, concurrent changes in the hepatic expression of GHRs and insulin-like growth factor-I (IGF-I) was evidenced. Moreover, their regulation occurred in conjunction with the summer spurt of growth rates and circulating levels of GH and IGF-I. Search of alternative splicing was carried out exhaustively for gilthead sea bream GHR, but Northern blot and 3' RACE failed to demonstrate the occurrence of short alternative messengers. Besides, RT-PCR screening did not reveal deletions or insertions that could lead to alternative reading frames. In agreement with this, cross-linking assays only evidenced two protein bands that match well with the size of glycosylated and non-glycosylated forms of the full-length GHR. If so, it appears that alternative splicing at the 3'end does not occur in gilthead sea bream, although different messengers for truncated or longer GHR variants already exist in turbot and black sea bream, respectively. The physiological relevance of this finding remains unclear, but perhaps it points out large inter-species differences in the heterogeneity of the GHR population. 相似文献
27.
Brinen LS Canaves JM Dai X Deacon AM Elsliger MA Eshaghi S Floyd R Godzik A Grittini C Grzechnik SK Guda C Jaroszewski L Karlak C Klock HE Koesema E Kovarik JS Kreusch A Kuhn P Lesley SA McMullan D McPhillips TM Miller MA Miller MD Morse A Moy K Ouyang J Robb A Rodrigues K Selby TL Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J Wang X West B Wolf G Taylor SS Hodgson KO Wooley J Wilson IA 《Proteins》2003,50(2):371-374
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