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141.
Gemma Aragonès Kalavathi Dasuri Opeoluwa Olukorede Sarah G. Francisco Carol Renneburg Caroline Kumsta Malene Hansen Shun Kageyama Masaaki Komatsu Sheldon Rowan Jonathan Volkin Michael Workman Wenxin Yang Paula Daza Diego Ruano Helena Dominguez‐Martín José Antonio Rodríguez‐Navarro Xue‐Liang Du Michael A. Brownlee Eloy Bejarano Allen Taylor 《Aging cell》2020,19(11)
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143.
Olivo Miotto Makoto Sekihara Shin-Ichiro Tachibana Masato Yamauchi Richard D. Pearson Roberto Amato Sonia Gonalves Somya Mehra Rintis Noviyanti Jutta Marfurt Sarah Auburn Ric N. Price Ivo Mueller Mie Ikeda Toshiyuki Mori Makoto Hirai Livingstone Tavul Manuel W. Hetzel Moses Laman Alyssa E. Barry Pascal Ringwald Jun Ohashi Francis Hombhanje Dominic P. Kwiatkowski Toshihiro Mita 《PLoS pathogens》2020,16(12)
The rapid and aggressive spread of artemisinin-resistant Plasmodium falciparum carrying the C580Y mutation in the kelch13 gene is a growing threat to malaria elimination in Southeast Asia, but there is no evidence of their spread to other regions. We conducted cross-sectional surveys in 2016 and 2017 at two clinics in Wewak, Papua New Guinea (PNG) where we identified three infections caused by C580Y mutants among 239 genotyped clinical samples. One of these mutants exhibited the highest survival rate (6.8%) among all parasites surveyed in ring-stage survival assays (RSA) for artemisinin. Analyses of kelch13 flanking regions, and comparisons of deep sequencing data from 389 clinical samples from PNG, Indonesian Papua and Western Cambodia, suggested an independent origin of the Wewak C580Y mutation, showing that the mutants possess several distinctive genetic features. Identity by descent (IBD) showed that multiple portions of the mutants’ genomes share a common origin with parasites found in Indonesian Papua, comprising several mutations within genes previously associated with drug resistance, such as mdr1, ferredoxin, atg18 and pnp. These findings suggest that a P. falciparum lineage circulating on the island of New Guinea has gradually acquired a complex ensemble of variants, including kelch13 C580Y, which have affected the parasites’ drug sensitivity. This worrying development reinforces the need for increased surveillance of the evolving parasite populations on the island, to contain the spread of resistance. 相似文献
144.
Sarah Cusser Christie Bahlai Scott M. Swinton G. Philip Robertson Nick M. Haddad 《Global Change Biology》2020,26(6):3715-3725
Agricultural management recommendations based on short‐term studies can produce findings inconsistent with long‐term reality. Here, we test the long‐term environmental sustainability and profitability of continuous no‐till agriculture on yield, soil water availability, and N2O fluxes. Using a moving window approach, we investigate the development and stability of several attributes of continuous no‐till as compared to conventional till agriculture over a 29‐year period at a site in the upper Midwest, US. Over a decade is needed to detect the consistent effects of no‐till. Both crop yield and soil water availability required 15 years or longer to generate patterns consistent with 29‐year trends. Only marginal trends for N2O fluxes appeared in this period. Relative profitability analysis suggests that after initial implementation, 86% of periods between 10 and 29 years recuperated the initial expense of no‐till implementation, with the probability of higher relative profit increasing with longevity. Importantly, statistically significant but misleading short‐term trends appeared in more than 20% of the periods examined. Results underscore the importance of decadal and longer studies for revealing consistent dynamics and emergent outcomes of no‐till agriculture, shown to be beneficial in the long term. 相似文献
145.
Comparing diversity levels in environmental samples: DNA sequence capture and metabarcoding approaches using 18S and COI genes 总被引:1,自引:0,他引:1
Hendrik Giebner Kathrin Langen Sarah J. Bourlat Sandra Kukowka Christoph Mayer Jonas J. Astrin Bernhard Misof Vera G. Fonseca 《Molecular ecology resources》2020,20(5):1333-1345
Environmental DNA studies targeting multiple taxa using metabarcoding provide remarkable insights into levels of species diversity in any habitat. The main drawbacks are the presence of primer bias and difficulty in identifying rare species. We tested a DNA sequence‐capture method in parallel with the metabarcoding approach to reveal possible advantages of one method over the other. Both approaches were performed using the same eDNA samples and the same 18S and COI regions, followed by high throughput sequencing. Metabarcoded eDNA libraries were PCR amplified with one primer pair from 18S and COI genes. DNA sequence‐capture libraries were enriched with 3,639 baits targeting the same gene regions. We tested amplicon sequence variants (ASVs) and operational taxonomic units (OTUs) in silico approaches for both markers and methods, using for this purpose the metabarcoding data set. ASVs methods uncovered more species for the COI gene, whereas the opposite occurred for the 18S gene, suggesting that clustering reads into OTUs could bias diversity richness especially using 18S with relaxed thresholds. Additionally, metabarcoding and DNA sequence‐capture recovered 80%–90% of the control sample species. DNA sequence‐capture was 8x more expensive, nonetheless it identified 1.5x more species for COI and 13x more genera for 18S than metabarcoding. Both approaches offer reliable results, sharing ca. 40% species and 72% families and retrieve more taxa when nuclear and mitochondrial markers are combined. eDNA metabarcoding is quite well established and low‐cost, whereas DNA‐sequence capture for biodiversity assessment is still in its infancy, is more time‐consuming but provides more taxonomic assignments. 相似文献
146.
147.
Emma Colucci-Guyon Aline Rifflet Sarah Saint-Auret Anaëlle da Costa Laurent Boucontet Thomas Laval Christophe Prehaud Nicolas Blanchard Jean-Pierre Levraud Ivo G. Boneca Caroline Demangel Laure Guenin-Mac 《PLoS neglected tropical diseases》2020,14(12)
Mycobacterium ulcerans, the causative agent of Buruli ulcer (BU) disease, is unique amongst human pathogens in its capacity to produce a lipid toxin called mycolactone. While previous studies have demonstrated that bacterially-released mycolactone diffuses beyond infection foci, the spatiotemporal distribution of mycolactone remained largely unknown. Here, we used the zebrafish model to provide the first global kinetic analysis of mycolactone’s diffusion in vivo, and multicellular co-culture systems to address the critical question of the toxin’s access to the brain.Zebrafish larvae were injected with a fluorescent-derivative of mycolactone to visualize the in vivo diffusion of the toxin from the peripheral circulation. A rapid, body-wide distribution of mycolactone was observed, with selective accumulation in tissues near the injection site and brain, together with an important excretion through the gastro-intestinal tract. Our conclusion that mycolactone reached the central nervous system was reinforced by an in cellulo model of human blood brain barrier and a mouse model of M. ulcerans-infection.Here we show that mycolactone has a broad but heterogenous profile of distribution in vivo. Our investigations in vitro and in vivo support the view that a fraction of bacterially-produced mycolactone gains access to the central nervous system. The relative persistence of mycolactone in the bloodstream suggests that assays of circulating mycolactone are relevant for BU disease monitoring and treatment optimization. 相似文献
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149.
Amino Acids - Unfortunately in the online published article, the name of compound “L-salicylidenealanine” was published with incorrect spelling in the section “Synthesis of... 相似文献
150.