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961.
Isabel C. Gouveia Jos M. Fiadeiro Joo A. Queiroz 《Biochemical Engineering Journal》2008,41(2):157-165
This study was undertaken to find the optimum conditions of a new enzymatic process to remove plant residues from wool. Commercial enzymatic preparations of Celluclast 1.5 L and Pectinex Ultra SP-L were selected in order to hydrolyze the polysaccharides in primary plant cell walls and middle lamella, resulting into more fragile residues easier to be removed. Since it was intended to define the optimal conditions for enzyme application, a four-factor central composite design was selected to study the effects of pH, temperature, enzyme concentration and wetting agent concentration, on the two selected responses, i.e., soluble reducing sugars (RS) and alkali solubility (AS) of wool to detect plant degradation and to evaluate wool quality, respectively. Results demonstrated that enzyme concentration was the most significant effect in plant residues degradation. A total enzyme concentration loading of 20 mL of both diluted enzymatic preparations in equal parts per 1 L of incubation solution (42.970 U/L of Celluclast preparation and PG 29.3 nkat/L + PME 2.537 nkat/L of Pectinex preparation), yielded an equivalent amount of 240.127 mg of glucose per 1.0 g of plant residue, at the optimal conditions: 40.56 °C, pH 4.0 and 1 mL Plurafac/L. SEM analysis has indicated an identical and important degradation of the plant residues, when compared to the conventional carbonization process, and wool quality has been preserved. 相似文献
962.
Bruno Studer Torben Asp Ursula Frei Stephan Hentrup Helena Meally Aurélie Guillard Susanne Barth Hilde Muylle Isabel Roldán-Ruiz Philippe Barre Carole Koning-Boucoiran Gerda Uenk-Stunnenberg Oene Dolstra Leif Skøt Kirsten P. Skøt Lesley B. Turner Mervyn O. Humphreys Roland Kölliker Niels Roulund Klaus K. Nielsen Thomas Lübberstedt 《Molecular breeding : new strategies in plant improvement》2008,21(4):533-548
An expressed sequence tag (EST) library of the key grassland species perennial ryegrass (Lolium perenne L.) has been exploited as a resource for microsatellite marker development. Out of 955 simple sequence repeat (SSR) containing
ESTs, 744 were used for primer design. Primer amplification was tested in eight genotypes of L. perenne and L. multiflorum representing (grand-) parents of four mapping populations and resulted in 464 successfully amplified EST-SSRs. Three hundred
and six primer pairs successfully amplified products in the mapping population VrnA derived from two of the eight genotypes
included in the original screening and revealed SSR polymorphisms for 143 ESTs. Here, we report on 464 EST-derived SSR primer
sequences of perennial ryegrass established in laboratory assays, providing a dedicated tool for marker assisted breeding
and comparative mapping within and among forage and turf grasses.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
963.
Steven E. Ullrich Janet A. Clancy Isabel A. del Blanco Hyejin Lee Vadim A. Jitkov Feng Han Andris Kleinhofs Kunihiko Matsui 《Molecular breeding : new strategies in plant improvement》2008,21(2):249-259
Preharvest sprouting (PHS) can be a problem in barley (Hordeum vulgare L.) especially malting barley, since rapid, uniform, and complete germination are critical. Information has been gained by
studying the genetics of dormancy (measured as germination percentage, GP). The objective of this study was to determine if
the quantitative trait loci (QTLs) discovered in previous research on dormancy are related to PHS. PHS was measured as sprout
score (SSc) based on visual sprouting in mist chamber-treated spikes and as alpha-amylase activity (AA) in kernels taken from
mist chamber-treated spikes that showed little or no visible sprouting. GP was also measured. All traits were measured at
0 and 14 days after physiological maturity. Evaluation of the spring six-row cross, Steptoe (dormant)/Morex (non-dormant)
doubled haploid mapping population grown in greenhouse and field environments revealed QTL regions for SSc, AA, and GP on
five, four, and six of the seven barley chromosomes, respectively. In total, seven and eight regions on five and six chromosomes
had effects ranging from 4 to 31% and 3 to 39% on PHS and dormancy, respectively. One chromosome 3H and three chromosome 5H
QTLs had the greatest effects. All PHS QTLs coincide with known dormancy QTLs, but some QTLs appear to be more important for
PHS than for dormancy. Key QTLs identified should benefit breeding of barley for a suitable balance between PHS and dormancy. 相似文献
964.
António Onofre Soares Isabel Borges Paulo A. V. Borges Geneviève Labrie Éric Lucas 《BioControl》2008,53(1):127-145
In recent years Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) has become a very popular insect among biological control practitioners and scientists, not only for its potential to be an efficient biological control agent but also because it is considered invasive. Individuals of this species were deliberately introduced into several countries for biological control of different arthropods pests. However the predator itself became an invasive species, affecting the dynamics and composition of several guilds through direct or indirect interactions with established species, including intraguild predation. In this paper we discuss the reasons why the species has a high invasiveness and what are the limits to invasion by this species. It is not clear if the invasiveness of the beetle is linked to its biological, ecological and behavioural abilities, or to other factors such as invasibility and interactions between the invaders, the noninvaders, and the habitat, which may in part explain the reasons of its success and help us to answer the question “what will stop the invader?” We also discuss the reason for the absence of the predator in the Azores islands. Despite the intentional introduction of H. axyridis in the Azores and the high number of individuals released, there are no records of this species in the wild, despite recent extensive sampling effort. In this paper we discuss the reasons for the apparent failure or the delay in establishment of the predator. One factor which may hamper the establishment of H. axyridis in some of the Azores islands is the absence of winter environmental conditions, mainly the temperature which is seldom lower than 12°C, essential for the induction of diapause. The lack of success in the establishment could be also related to functional diversity saturation, that is species saturation and competitive exclusion of H. axyridis by other previously established species may be operating. 相似文献
965.
Phylogenetic analysis of the archaeal community in an alkaline-saline soil of the former lake Texcoco (Mexico) 总被引:1,自引:0,他引:1
Valenzuela-Encinas C Neria-González I Alcántara-Hernández RJ Enríquez-Aragón JA Estrada-Alvarado I Hernández-Rodríguez C Dendooven L Marsch R 《Extremophiles : life under extreme conditions》2008,12(2):247-254
The soil of the former lake Texcoco is an extreme environment localized in the valley of Mexico City, Mexico. It is highly
saline and alkaline, where Na+, Cl−, HCO3− and CO32− are the predominant ions, with a pH ranging from 9.8 to 11.7 and electrolytic conductivities in saturation extracts from
22 to 150 dS m−1. Metagenomic DNA from the archaeal community was extracted directly from soil and used as template to amplify 16S ribosomal
gene by PCR. PCR products were used to construct gene libraries. The ribosomal library showed that the archaeal diversity
included Natronococcus sp., Natronolimnobius sp., Natronobacterium sp., Natrinema sp., Natronomonas sp., Halovivax sp., “Halalkalicoccus jeotgali” and novel clades within the family of Halobacteriaceae. Four clones could not be classified. It was found that the archaeal
diversity in an alkaline-saline soil of the former lake Texcoco, Mexico, was low, but showed yet uncharacterized and unclassified
species.
César Valenzuela-Encinas and Isabel Neria-González contributed equally to this publication. 相似文献
966.
Meiotic progression requires the translational activation of stored maternal mRNAs, such as those encoding cyclin B1 or mos. The translation of these mRNAs is regulated by the cytoplasmic polyadenylation element (CPE) present in their 3'UTRs, which recruits the CPE-binding protein CPEB. This RNA-binding protein not only dictates the timing and extent of translational activation by cytoplasmic polyadenylation but also participates, together with the translational repressor Maskin, in the transport and localization, in a quiescent state, of its targets to subcellular locations where their translation will take place. During the early development of Xenopus laevis, CPEB localizes at the animal pole of oocytes and later on at embryonic spindles and centrosomes. Disruption of embryonic CPEB-mediated translational regulation results in abnormalities in the mitotic apparatus and inhibits embryonic mitosis. Here we show that spindle-localized translational activation of CPE-regulated mRNAs, encoding for proteins with a known function in spindle assembly and chromosome segregation, is essential for completion of the first meiotic division and for chromosome segregation in Xenopus oocytes. 相似文献
967.
Santos Alonso Neskuts Izagirre Isabel Smith-Zubiaga Jesús Gardeazabal José Luís Díaz-Ramón José Luís Díaz-Pérez Diana Zelenika María Dolores Boyano Nico Smit Concepción de la Rúa 《BMC evolutionary biology》2008,8(1):74
Background
The observed correlation between ultraviolet light incidence and skin color, together with the geographical apportionment of skin reflectance among human populations, suggests an adaptive value for the pigmentation of the human skin. We have used Affymetrix U133a v2.0 gene expression microarrays to investigate the expression profiles of a total of 9 melanocyte cell lines (5 from lightly pigmented donors and 4 from darkly pigmented donors) plus their respective unirradiated controls. In order to reveal signatures of selection in loci with a bearing on skin pigmentation in humans, we have resequenced between 4 to 5 kb of the proximal regulatory regions of three of the most differently expressed genes, in the expectation that variation at regulatory regions might account for intraespecific morphological diversity, as suggested elsewhere. 相似文献968.
Jose V Llorens Jonathan B Clark Isabel Martínez-Garay Sirena Soriano Rosa de Frutos María J Martínez-Sebastián 《BMC evolutionary biology》2008,8(1):302
Background
Sequences homologous to the gypsy retroelement from Drosophila melanogaster are widely distributed among drosophilids. The structure of gypsy includes an open reading frame resembling the retroviral gene env, which is responsible for the infectious properties of retroviruses. 相似文献969.
Michela Baccini Eva-Maria Bachmaier Annibale Biggeri Mark V. Boekschoten Freek G. Bouwman Lorraine Brennan Robert Caesar Saverio Cinti Susan L. Coort Katie Crosley Hannelore Daniel Christian A. Drevon Susan Duthie Lars Eijssen Ruan M. Elliott Marjan van Erk Chris Evelo Mike Gibney Carolin Heim Graham W. Horgan Ian T. Johnson Thomas Kelder Robert Kleemann Teake Kooistra Martijn P. van Iersel Edwin C. Mariman Claus Mayer Gerard McLoughlin Michael Müller Francis Mulholland Ben van Ommen Abigael C. Polley Estelle Pujos-Guillot Isabel Rubio-Aliaga Helen M. Roche Baukje de Roos Manuela Sailer Giulia Tonini Lynda M. Williams Nicole de Wit 《Genes & nutrition》2008,3(3-4):147-151
970.
Antonysamy SS Aubol B Blaney J Browner MF Giannetti AM Harris SF Hébert N Hendle J Hopkins S Jefferson E Kissinger C Leveque V Marciano D McGee E Nájera I Nolan B Tomimoto M Torres E Wright T 《Bioorganic & medicinal chemistry letters》2008,18(9):2990-2995
Non-nucleoside inhibitors of HCV NS5b RNA polymerase were discovered by a fragment-based lead discovery approach, beginning with crystallographic fragment screening. The NS5b binding affinity and biochemical activity of fragment hits and inhibitors was determined by surface plasmon resonance (Biacore) and an enzyme inhibition assay, respectively. Crystallographic fragment screening hits with 1–10 mM binding affinity (KD) were iteratively optimized to give leads with 200 nM biochemical activity and low μM cellular activity in a Replicon assay. 相似文献