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941.
Paul Ramos Michael Lynch Min Hu John P. Y. Arnould Richard Norman Ian Beveridge 《Systematic parasitology》2013,85(1):65-78
This study presents morphological and molecular data on hookworms from the Australian fur seal Arctocephalus pusillus doriferus (Schreber) currently identified in Australian waters as Uncinaria hamiltoni Baylis, 1933. Additional specimens from the Australian sea lion Neophoca cinerea (Péron) and the New Zealand fur seal Arctocephalus forsteri (Lesson) from Australia, and the Southern elephant seal Mirounga leonina (Linnaeus) from Antarctica, were included. Using the internal transcribed spacer (ITS), hookworms from A. p. doriferus, N. cinerea and A. forsteri were found to be genetically similar but distinct from Uncinaria spp. found in M. leonina from Antarctica, as well as from Zalophus californianus (Lesson) and Callorhinus ursinus (Linnaeus) from California. Few morphological differences were detected between these taxa. 相似文献
942.
André Moreni Lopes Valéria de Carvalho Santos-Ebinuma Leticia Celia de Lencastre Novaes João Vitor Dutra Molino Leandro Ramos Souza Barbosa Adalberto Pessoa Jr Carlota de Oliveira Rangel-Yagui 《Applied microbiology and biotechnology》2013,97(14):6201-6209
Lipopolysaccharide endotoxins (LPS) are the most common pyrogenic substances in recombinant peptides and proteins purified from Gram-negative bacteria, such as Escherichia coli. In this respect, aqueous two-phase micellar systems (ATPMS) have already proven to be a good strategy to purify recombinant proteins of pharmaceutical interest and remove high LPS concentrations. In this paper, we review our recent experimental work in protein partitioning in Triton X-114 ATPMS altogether with some new results and show that LPS–protein aggregation can influence both protein and LPS partitioning. Green fluorescent protein (GFPuv) was employed as a model protein. The ATPMS technology proved to be effective for high loads of LPS removal into the micelle-rich phase (%REMLPS?>?98 %) while GFPuv partitioned preferentially to the micelle-poor phase (K GFPuv?<?1.00) due to the excluded-volume interactions. However, theoretically predicted protein partition coefficient values were compared with experimentally obtained ones, and good agreement was found only in the absence of LPS. Dynamic light scattering measurements showed that protein–LPS interactions were taking place and influenced the partitioning process. We believe that this phenomenon should be considered in LPS removal employing any kind of aqueous two-phase system. Nonetheless, ATPMS can still be considered as an efficient strategy for high loads of LPS removal, but being aware that the excluded-volume partitioning theory available might overestimate partition coefficient values due to the presence of protein–LPS aggregation. 相似文献
943.
944.
Cota J Alvarez TM Citadini AP Santos CR de Oliveira Neto M Oliveira RR Pastore GM Ruller R Prade RA Murakami MT Squina FM 《Biochemical and biophysical research communications》2011,(4):590-594
1,3-β-Glucan depolymerizing enzymes have considerable biotechnological applications including biofuel production, feedstock-chemicals and pharmaceuticals. Here we describe a comprehensive functional characterization and low-resolution structure of a hyperthermophilic laminarinase from Thermotoga petrophila (TpLam). We determine TpLam enzymatic mode of operation, which specifically cleaves internal β-1,3-glucosidic bonds. The enzyme most frequently attacks the bond between the 3rd and 4th residue from the non-reducing end, producing glucose, laminaribiose and laminaritriose as major products. Far-UV circular dichroism demonstrates that TpLam is formed mainly by beta structural elements, and the secondary structure is maintained after incubation at 90 °C. The structure resolved by small angle X-ray scattering, reveals a multi-domain structural architecture of a V-shape envelope with a catalytic domain flanked by two carbohydrate-binding modules. 相似文献
945.
Dyeing Plants and Knowledge Transfer in the Yungas Communities of Northwest Argentina. In the Yungas region of the Salta province, Argentina, interest in the use of plant dyes has revived due to new market demands
and the growth of rural tourism. In this study we compare the use of dyeing plants recorded between 1994 and 2000 with those
used in 2007 and 2008. We also address factors currently involved in the acquisition and transmission of knowledge. We worked
with 39 randomly chosen participants (of which 11 were artisans) in the first stage, and 32 artisans in the second stage.
Information was gathered during semi–structured interviews and structured questionnaires. Eleven and 57 dye plant species,
and 10 and 2 mordants, were registered in the first and second stage, respectively. The use of soft plant parts has increased,
relative to the employment of roots and barks. Pastels predominate among the colors obtained. Mothers are the main transmitters
of this knowledge; however, new mechanisms of knowledge acquisition and transfer are gaining importance. These results provide
an alternative for the diversification and quality of existing crafts. 相似文献
946.
Cristina Castillejo Veronika Waurich Henning Wagner Rubn Ramos Nicols Oiza Pilar Muoz Juan C. Trivio Julie Caruana Zhongchi Liu Nicols Cobo Michael A. Hardigan Steven J. Knapp Jos G. Vallarino Sonia Osorio Carmen Martín-Pizarro David Pos Tuomas Toivainen Timo Hytnen Youngjae Oh Christopher R. Barbey Vance M. Whitaker Seonghee Lee Klaus Olbricht Jos F. Snchez-Sevilla Iraida Amaya 《The Plant cell》2020,32(12):3723
947.
Jssica Rodrigues da Silva Ana Karolina Leite Pais Greecy Mirian Rodrigues Albuquerque Adriano Mrcio Freire Silva Wilson Jos Silva Junior Valdir de Queiroz Balbino Maria Esther Noronha Fonseca Marco Aurlio Siqueira da Gama Elineide Barbosa de Souza Rosa de Lima Ramos Mariano 《Genetics and molecular biology》2020,43(4)
Ralstonia solanacearum is the causal agent of Moko disease in bananas, which in the state of Sergipe in northeastern Brazil causes “Sergipe facies”. This disease induces atypical symptoms similar to those of Bugtok disease in the Philippines. This study was conducted to sequence, assemble, and annotate the genomes of the Sergipe facies-causing isolates SFC and IBSBF2570 (sequevar IIA-53) and compare their genomes with two representative isolates causing Bugtok disease. The genomes were sequenced and assembled, resulting in lengths of 5.58 Mb (SFC) and 5.46 Mb (IBSBF2570) in 185 and 174 contigs, respectively. The isolates of Sergipe facies and Bugtok disease showed similarities in their gene contents. We identified 5,668 information clusters, 3,752 of which were shared by all genomes (core genes). Moreover, 3,585 single-copy genes were identified. Isolates causing Bugtok disease exclusively shared 266 more information clusters than the isolates causing Sergipe facies. These results suggest that Sergipe facies and Bugtok disease isolates show high genomic similarity. However, the similarity is even greater between the Bugtok disease isolates. This may be because of their longer period of interaction compared to Sergipe facies isolates. 相似文献
948.
949.
Rommel Thiago Jucá Ramos Adriana Ribeiro Carneiro Siomar de Castro Soares Anderson Rodrigues dos Santos Sintia Almeida Luis Guimar?es Flávia Figueira Eudes Barbosa Andreas Tauch Vasco Azevedo Artur Silva 《Microbial biotechnology》2013,6(2):150-156
New sequencing platforms have enabled rapid decoding of complete prokaryotic genomes at relatively low cost. The Ion Torrent platform is an example of these technologies, characterized by lower coverage, generating challenges for the genome assembly. One particular problem is the lack of genomes that enable reference-based assembly, such as the one used in the present study, Corynebacterium pseudotuberculosis biovar equi, which causes high economic losses in the US equine industry. The quality treatment strategy incorporated into the assembly pipeline enabled a 16-fold greater use of the sequencing data obtained compared with traditional quality filter approaches. Data preprocessing prior to the de novo assembly enabled the use of known methodologies in the next-generation sequencing data assembly. Moreover, manual curation was proved to be essential for ensuring a quality assembly, which was validated by comparative genomics with other species of the genus Corynebacterium. The present study presents a modus operandi that enables a greater and better use of data obtained from semiconductor sequencing for obtaining the complete genome from a prokaryotic microorganism, C. pseudotuberculosis, which is not a traditional biological model such as Escherichia coli. 相似文献
950.
Juan Téllez-Sosa Mario Henry Rodríguez Rosa E. Gómez-Barreto Humberto Valdovinos-Torres Ana Cecilia Hidalgo Pablo Cruz-Hervert René Santos Luna Erik Carrillo-Valenzo Celso Ramos Lourdes García-García Jesús Martínez-Barnetche 《PloS one》2013,8(7)