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951.
Fluit Ad C. Bayjanov Jumamurat R. Aguilar María Díez Cantón Rafael Tunney Michael M. Elborn J. Stuart van Westreenen Mireille Ekkelenkamp Miquel B. 《Antonie van Leeuwenhoek》2021,114(10):1721-1733
Antonie van Leeuwenhoek - To improve understanding of the role of Ralstonia in cystic fibrosis (CF), whole genomes of 18 strains from clinical samples were sequenced using Illumina technology.... 相似文献
952.
Anne Bergougnoux Isabelle Rivals Alessandro Liquori Caroline Raynal Jessica Varilh Milena Magalh?es Marie-José Perez Nicole Bigi Marie Des Georges Rapha?l Chiron Ahmed Saad Squalli-Houssaini Mireille Claustres Albertina De Sario 《Epigenetics》2014,9(7):1007-1017
The genetic mechanisms that regulate CFTR, the gene responsible for cystic fibrosis, have been widely investigated in cultured cells. However, mechanisms responsible for tissue-specific and time-specific expression are not completely elucidated in vivo. Through the survey of public databases, we found that the promoter of CFTR was associated with bivalent chromatin in human embryonic stem (ES) cells. In this work, we analyzed fetal (at different stages of pregnancy) and adult tissues and showed that, in digestive and lung tissues, which expressed CFTR, H3K4me3 was maintained in the promoter. Histone acetylation was high in the promoter and in two intronic enhancers, especially in fetal tissues. In contrast, in blood cells, which did not express CFTR, the bivalent chromatin was resolved (the promoter was labeled by the silencing mark H3K27me3). Cis-regulatory sequences were associated with lowly acetylated histones. We also provide evidence that the tissue-specific expression of CFTR is not regulated by dynamic changes of DNA methylation in the promoter. Overall, this work shows that a balance between activating and repressive histone modifications in the promoter and intronic enhancers results in the fine regulation of CFTR expression during development, thereby ensuring tissue specificity. 相似文献
953.
Micheline El Khoury Hichem Azzouz Alain Chavanieu Nouha Abdelmalak Joël Chopineau Mireille Kallassy Awad 《Archives of microbiology》2014,196(6):435-444
The aim of this study was to characterize new Bacillus thuringiensis strains that have a potent insecticidal activity against Ephestia kuehniella larvae. Strains harboring cry1A genes were tested for their toxicity, and the Lip strain showed a higher insecticidal activity compared to that of the reference strain HD1 (LC50 of Lip and HD1 were 33.27 and 128.61 μg toxin/g semolina, respectively). B. thuringiensis Lip harbors and expresses cry1Aa, cry1Ab, cry1Ac, cry1Ad and cry2A. DNA sequencing revealed several polymorphisms in Lip Cry1Aa and Cry1Ac compared to the corresponding proteins of HD1. The activation process using Ephestia kuehniella midgut juice showed that Lip Cry1A proteins were more stable in the presence of larval proteases. Moreover, LipCry1A proteins exhibited higher insecticidal activity against these larvae. These results indicate that Lip is an interesting strain that could be used as an alternative to the worldwide used strain HD1. 相似文献
954.
Olivier J. Wouters Philip W. Downs Kathryn L. Zoerhoff Kathryn R. Crowley Hannah Frawley Jennifer Einberg Brian K. Chu Molly A. Brady Roland Oscar Mireille Jeudi Anne-Marie Desormeaux Karleen Coly Abdel N. Direny Garib D. Thakur Raj K. Pokharel Shekhar Sharma Dharmpal P. Raman Santigie Sesay Mustapha Sonnie Bernard Kilembe Upendo Mwingira Aya Yajima 《PLoS neglected tropical diseases》2014,8(2)
955.
956.
Wafa Bouleftour Maya Boudiffa Ndeye Marième Wade-Gueye Guéna?lle Bou?t Marco Cardelli Norbert Laroche Arnaud Vanden-Bossche Mireille Thomas Edith Bonnelye Jane E. Aubin Laurence Vico Marie Hélène Lafage-Proust Luc Malaval 《PloS one》2014,9(5)
Adult Ibsp-knockout mice (BSP−/−) display shorter stature, lower bone turnover and higher trabecular bone mass than wild type, the latter resulting from impaired bone resorption. Unexpectedly, BSP knockout also affects reproductive behavior, as female mice do not construct a proper "nest" for their offsprings. Multiple crossing experiments nonetheless indicated that the shorter stature and lower weight of BSP−/− mice, since birth and throughout life, as well as their shorter femur and tibia bones are independent of the genotype of the mothers, and thus reflect genetic inheritance. In BSP−/− newborns, µCT analysis revealed a delay in membranous primary ossification, with wider cranial sutures, as well as thinner femoral cortical bone and lower tissue mineral density, reflected in lower expression of bone formation markers. However, trabecular bone volume and osteoclast parameters of long bones do not differ between genotypes. Three weeks after birth, osteoclast number and surface drop in the mutants, concomitant with trabecular bone accumulation. The growth plates present a thinner hypertrophic zone in newborns with lower whole bone expression of IGF-1 and higher IHH in 6 days old BSP−/− mice. At 3 weeks the proliferating zone is thinner and the hypertrophic zone thicker in BSP−/− than in BSP+/+ mice of either sex, maybe reflecting a combination of lower chondrocyte proliferation and impaired cartilage resorption. Six days old BSP−/− mice display lower osteoblast marker expression but higher MEPE and higher osteopontin(Opn)/Runx2 ratio. Serum Opn is higher in mutants at day 6 and in adults. Thus, lack of BSP alters long bone growth and membranous/cortical primary bone formation and mineralization. Endochondral development is however normal in mutant mice and the accumulation of trabecular bone observed in adults develops progressively in the weeks following birth. Compensatory high Opn may allow normal endochondral development in BSP−/− mice, while impairing primary mineralization. 相似文献
957.
958.
Béatrice Siguier Mireille Haon Virginie Nahoum Marlène Marcellin Odile Burlet-Schiltz Pedro M. Coutinho Bernard Henrissat Lionel Mourey Michael J. O'Donohue Jean-Guy Berrin Samuel Tranier Claire Dumon 《The Journal of biological chemistry》2014,289(8):5261-5273
α-l-Arabinofuranosidases are glycoside hydrolases that specifically hydrolyze non-reducing residues from arabinose-containing polysaccharides. In the case of arabinoxylans, which are the main components of hemicellulose, they are part of microbial xylanolytic systems and are necessary for complete breakdown of arabinoxylans. Glycoside hydrolase family 62 (GH62) is currently a small family of α-l-arabinofuranosidases that contains only bacterial and fungal members. Little is known about the GH62 mechanism of action, because only a few members have been biochemically characterized and no three-dimensional structure is available. Here, we present the first crystal structures of two fungal GH62 α-l-arabinofuranosidases from the basidiomycete Ustilago maydis (UmAbf62A) and ascomycete Podospora anserina (PaAbf62A). Both enzymes are able to efficiently remove the α-l-arabinosyl substituents from arabinoxylan. The overall three-dimensional structure of UmAbf62A and PaAbf62A reveals a five-bladed β-propeller fold that confirms their predicted classification into clan GH-F together with GH43 α-l-arabinofuranosidases. Crystallographic structures of the complexes with arabinose and cellotriose reveal the important role of subsites +1 and +2 for sugar binding. Intriguingly, we observed that PaAbf62A was inhibited by cello-oligosaccharides and displayed binding affinity to cellulose although no activity was observed on a range of cellulosic substrates. Bioinformatic analyses showed that UmAbf62A and PaAbf62A belong to two distinct subfamilies within the GH62 family. The results presented here provide a framework to better investigate the structure-function relationships within the GH62 family. 相似文献
959.
Austin Chen Christopher Bayly Olivier Bezençon Sylvia Richard-Bildstein Daniel Dubé Laurence Dubé Sébastien Gagné Michel Gallant Mireille Gaudreault Erich Grimm Robert Houle Patrick Lacombe Sébastien Laliberté Jean-François Lévesque Suzanna Liu Dwight MacDonald Bruce Mackay David Martin Dan McKay David Powell Sylvie Toulmond 《Bioorganic & medicinal chemistry letters》2010,20(7):2204-2209
The discovery and SAR of a new series of substituted amino propanamide renin inhibitors are herein described. This work has led to the preparation of compounds with in vitro and in vivo profiles suitable for further development. Specifically, challenges pertaining to oral bioavailability, covalent binding and time-dependent CYP 3A4 inhibition were overcome thereby culminating in the identification of compound 50 as an optimized renin inhibitor with good efficacy in the hypertensive double-transgenic rat model. 相似文献
960.
Ga?l Panis Yohann Duverger Elise Courvoisier-Dezord Stéphanie Champ Emmanuel Talla Mireille Ansaldi 《PLoS genetics》2010,6(10)
Temperate phages have the ability to maintain their genome in their host, a process called lysogeny. For most, passive replication of the phage genome relies on integration into the host''s chromosome and becoming a prophage. Prophages remain silent in the absence of stress and replicate passively within their host genome. However, when stressful conditions occur, a prophage excises itself and resumes the viral cycle. Integration and excision of phage genomes are mediated by regulated site-specific recombination catalyzed by tyrosine and serine recombinases. In the KplE1 prophage, site-specific recombination is mediated by the IntS integrase and the TorI recombination directionality factor (RDF). We previously described a sub-family of temperate phages that is characterized by an unusual organization of the recombination module. Consequently, the attL recombination region overlaps with the integrase promoter, and the integrase and RDF genes do not share a common activated promoter upon lytic induction as in the lambda prophage. In this study, we show that the intS gene is tightly regulated by its own product as well as by the TorI RDF protein. In silico analysis revealed that overlap of the attL region with the integrase promoter is widely encountered in prophages present in prokaryotic genomes, suggesting a general occurrence of negatively autoregulated integrase genes. The prediction that these integrase genes are negatively autoregulated was biologically assessed by studying the regulation of several integrase genes from two different Escherichia coli strains. Our results suggest that the majority of tRNA-associated integrase genes in prokaryotic genomes could be autoregulated and that this might be correlated with the recombination efficiency as in KplE1. The consequences of this unprecedented regulation for excisive recombination are discussed. 相似文献