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91.
Jenna Morissette Sula Swart Tyson J. MacCormack Suzanne Currie Andrea J. Morash 《Journal of fish biology》2021,98(6):1585-1589
Typically, laboratory studies on the physiological effects of temperature are conducted using stable acclimation temperatures. Nonetheless, information extrapolated from these studies may not accurately represent wild populations living in thermally variable environments. The aim of this study was to compare the growth rate, metabolism and swimming performance of wild Atlantic salmon exposed to cycling temperatures, 16–21°C, and stable acclimation temperatures, 16, 18.5, 21°C. Growth rate, metabolic rate, swimming performance and anaerobic metabolites did not change among acclimation groups, suggesting that within Atlantic salmon's thermal optimum range, temperature variation has no effect on these physiological properties. 相似文献
92.
93.
Olga Camacho Lydiane Mattio Stefano Draisma Suzanne Fredericq Guillermo Diaz-Pulido 《分类学与生物多样性》2013,11(2):105-130
94.
Suzanne Peyrottes Béatrice Mestre Fabienne Burlina Michael J. Gait 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1443-1448
Abstract We describe a peptide fragment, solid-phase coupling strategy for synthesis of peptide-oligonucleotide conjugates. Model conjugates contained a hydrophobic tetrapeptide, a hydrophobic influenza virus fusion nonapeptide, or a basic octapeptide of the HIV-1 Tat protein coupled to either dT12 or a 16-mer anti-Tat oligodeoxyribonucleotide. Conjugation yields were improved by removal of internucleotide 2-cyanoethyl groups prior to peptide coupling and by use of a C12 spacer between peptide and oligonucleotide. 相似文献
95.
Vincenzo Forgetta Gary Leveque Joana Dias Deborah Grove Robert Lyons Jr. Suzanne Genik Chris Wright Sushmita Singh Nichole Peterson Michael Zianni Jan Kieleczawa Robert Steen Anoja Perera Doug Bintzler Scottie Adams Will Hintz Volker Jacobi Louis Bernier Roger Levesque Ken Dewar 《Journal of biomolecular techniques》2013,24(1):39-49
As part of the DNA Sequencing Research Group of the Association of Biomolecular Resource Facilities, we have tested the reproducibility of the Roche/454 GS-FLX Titanium System at five core facilities. Experience with the Roche/454 system ranged from <10 to >340 sequencing runs performed. All participating sites were supplied with an aliquot of a common DNA preparation and were requested to conduct sequencing at a common loading condition. The evaluation of sequencing yield and accuracy metrics was assessed at a single site. The study was conducted using a laboratory strain of the Dutch elm disease fungus Ophiostoma novo-ulmi strain H327, an ascomycete, vegetatively haploid fungus with an estimated genome size of 30–50 Mb. We show that the Titanium System is reproducible, with some variation detected in loading conditions, sequencing yield, and homopolymer length accuracy. We demonstrate that reads shorter than the theoretical minimum length are of lower overall quality and not simply truncated reads. The O. novo-ulmi H327 genome assembly is 31.8 Mb and is comprised of eight chromosome-length linear scaffolds, a circular mitochondrial conti of 66.4 kb, and a putative 4.2-kb linear plasmid. We estimate that the nuclear genome encodes 8613 protein coding genes, and the mitochondrion encodes 15 genes and 26 tRNAs. 相似文献
96.
97.
Investigating the Impact of Storage Conditions on Microbial Community Composition in Soil Samples 总被引:1,自引:0,他引:1
Benjamin E. R. Rubin Sean M. Gibbons Suzanne Kennedy Jarrad Hampton-Marcell Sarah Owens Jack A. Gilbert 《PloS one》2013,8(7)
Recent advances in DNA sequencing technologies have allowed scientists to probe increasingly complex biological systems, including the diversity of bacteria in the environment. However, despite a multitude of recent studies incorporating these methods, many questions regarding how environmental samples should be collected and stored still persist. Here, we assess the impact of different soil storage conditions on microbial community composition using Illumina-based 16S rRNA V4 amplicon sequencing. Both storage time and temperature affected bacterial community composition and structure. Frozen samples maintained the highest alpha diversity and differed least in beta diversity, suggesting the utility of cold storage for maintaining consistent communities. Samples stored for intermediate times (three and seven days) had both the highest alpha diversity and the largest differences in overall beta diversity, showing the degree of community change after sample collection. These divergences notwithstanding, differences in neither storage time nor storage temperature substantially altered overall communities relative to more than 500 previously examined soil samples. These results systematically support previous studies and stress the importance of methodological consistency for accurate characterization and comparison of soil microbiological assemblages. 相似文献
98.
Brian Becknell John David Spencer Ashley R. Carpenter Xi Chen Aspinder Singh Suzanne Ploeger Jennifer Kline Patrick Ellsworth Birong Li Ehrhardt Proksch Andrew L. Schwaderer David S. Hains Sheryl S. Justice Kirk M. McHugh 《PloS one》2013,8(10)
Beta defensins (BDs) are cationic peptides with antimicrobial activity that defend epithelial surfaces including the skin, gastrointestinal, and respiratory tracts. However, BD expression and function in the urinary tract are incompletely characterized. The purpose of this study was to describe Beta Defensin-1 (BD-1) expression in the lower urinary tract, regulation by cystitis, and antimicrobial activity toward uropathogenic Escherichia coli (UPEC) in vivo. Human DEFB1 and orthologous mouse Defb1 mRNA are detectable in bladder and ureter homogenates, and human BD-1 protein localizes to the urothelium. To determine the relevance of BD-1 to lower urinary tract defense in vivo, we evaluated clearance of UPEC by Defb1 knockout (Defb1
-/-) mice. At 6, 18, and 48 hours following transurethral UPEC inoculation, no significant differences were observed in bacterial burden in bladders or kidneys of Defb1
-/- and wild type C57BL/6 mice. In wild type mice, bladder Defb1 mRNA levels decreased as early as two hours post-infection and reached a nadir by six hours. RT-PCR profiling of BDs identified expression of Defb3 and Defb14 mRNA in murine bladder and ureter, which encode for mBD-3 and mBD-14 protein, respectively. MBD-14 protein expression was observed in bladder urothelium following UPEC infection, and both mBD-3 and mBD-14 displayed dose-dependent bactericidal activity toward UPEC in vitro. Thus, whereas mBD-1 deficiency does not alter bladder UPEC burden in vivo, we have identified mBD-3 and mBD-14 as potential mediators of mucosal immunity in the lower urinary tract. 相似文献
99.
Cyrille Goarant Pascale Bourhy Eric D'Ortenzio Sylvie Dartevelle Carine Mauron Marie-Estelle Soupé-Gilbert Lilian Bruyère-Ostells Ann-Claire Gourinat Mathieu Picardeau Faridabano Nato Suzanne Chanteau 《PLoS neglected tropical diseases》2013,7(6)
Background: Leptospirosis is a growing public health concern in many tropical and subtropical countries. However, its diagnosis is difficult because of non-specific symptoms and concurrent other endemic febrile diseases. In many regions, the laboratory diagnosis is not available due to a lack of preparedness and simple diagnostic assay or difficult access to reference laboratories. Yet, an early antibiotic treatment is decisive to the outcome. The need for Rapid Diagnostic Tests (RDTs) for bedside diagnosis of leptospirosis has been recognized. We developed a vertical flow immunochromatography strip RDT detecting anti-Leptospira human IgM and evaluated it in patients from New Caledonia, France, and French West Indies.
Methodology/Principal Findings: Whole killed Leptospira fainei cells were used as antigen for the test line and purified human IgM as the control line. The mobile phase was made of gold particles conjugated with goat anti-human IgM. Standards for Reporting of Diagnostic Accuracy criteria were used to assess the performance of this RDT. The Microscopic Agglutination Test (MAT) was used as the gold standard with a cut-off titer of ≥400. The sensitivity was 89.8% and the specificity 93.7%. Positive and negative Likelihood Ratios of 14.18 and 0.108 respectively, and a Diagnostic Odds Ratio of 130.737 confirmed its usefulness. This RDT had satisfactory reproducibility, repeatability, thermal tolerance and shelf-life. The comparison with MAT evidenced the earliness of the RDT to detect seroconversion. When compared with other RDT, the Vertical Flow RDT developed displayed good diagnostic performances.
Conclusions/Significance
This RDT might be used as a point of care diagnostic tool in limited resources countries. An evaluation in field conditions and in other epidemiological contexts should be considered to assess its validity over a wider range of serogroups or when facing different endemic pathogens. It might prove useful in endemic contexts or outbreak situations. 相似文献100.
Raymond N. Moynihan Georga P. E. Cooke Jenny A. Doust Lisa Bero Suzanne Hill Paul P. Glasziou 《PLoS medicine》2013,10(8)