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21.
Figures in scientific publications are critically important because they often show the data supporting key findings. Our systematic review of research articles published in top physiology journals (n = 703) suggests that, as scientists, we urgently need to change our practices for presenting continuous data in small sample size studies. Papers rarely included scatterplots, box plots, and histograms that allow readers to critically evaluate continuous data. Most papers presented continuous data in bar and line graphs. This is problematic, as many different data distributions can lead to the same bar or line graph. The full data may suggest different conclusions from the summary statistics. We recommend training investigators in data presentation, encouraging a more complete presentation of data, and changing journal editorial policies. Investigators can quickly make univariate scatterplots for small sample size studies using our Excel templates. 相似文献
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The aim of this study was to evaluate hydrophobicity of fungal strains of Candida sp. isolated from clinical materials of patients with fungal infections. Two hundred and eighty one strains of C. albicans and 29 strains belonging to the other species of Candida were tested in salt aggregation test (SAT). Strong hydrophobicity (autoaggregation in the test) was found in 29.4% of tested strains. The majority of them was isolated from vagina. In 20 randomly selected strains hydrophobicity was measured not only by salt aggregation test but also by hydrophobic interaction chromatography (MIC). The ability to attach to buccal epithelial cells in vitro was compared between 50 strongly hydrophobic strains and 30 with low hydrophobicity. The former strains attached significantly stronger (p less than 0.001). 相似文献
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Electrochemical real-time monitoring of ligand binding to an engineered opioid receptor specific for morphine is reported. In the particular systems studied, 90% of the binding was found to be completed after only 85-120 s. Thus, the binding kinetics has proven to be more rapid than previously believed. The observed association rate constant for the morphine binding reaction was calculated to be 215 M(-1)s(-1). A theoretical analysis of the experimental binding data suggested that the binding sites of the engineered opioid receptor could best be described by a model having two populations of binding sites: K(D)=40 microM (13 micromol/g) and K(D)=205 microM (29 micromol/g). Furthermore, a theoretical model was developed in order to explain the observed binding of the engineered opioid receptor. This model suggested that the binding sites on the polymer surface are up to 5.1A deep and they allow 100% of the ligand (morphine) to anchor itself into the site. The predicted theoretical maximum binding capacity for the reported receptor is calculated to be approximately 2 mmol/g polymer (based on an increase of cavity density). 相似文献
26.
Singh N Pandey SK Anand N Dwivedi R Singh S Sinha SK Chaturvedi V Jaiswal N Srivastava AK Shah P Siddiqui MI Tripathi RP 《Bioorganic & medicinal chemistry letters》2011,21(15):4404-4408
An economical and efficient one step synthesis of a series of 8-(arylidene)-4-(aryl)-5,6,7,8-tetrahydro-quinazolin-2-ylamines and 9-(arylidene)-4-(aryl)-6,7,8,9-tetrahydro-5H-cycloheptapyrimidin-2-ylamines by the reaction of bis-benzylidene cycloalkanones and guanidine hydrochloride in presence of NaH has been developed. All the synthesized compounds were evaluated against Mycobacterium tuberculosis H37Rv strain and the α-glucosidase and glycogen phosphorylase enzymes. Few of the compounds have shown interesting in vitro activity with MIC up to 3.12 μg/mL against M. tuberculosis and very good inhibition of α-glucosidase and glycogen phosphorylase enzymes. The most potent non toxic compound 40 exhibited about 58% ex vivo activity at MIC of 3.12 μg/mL. The present study opens a new gate to synthesize antitubercular agents for diabetic TB patients. In silico docking studies indicate that mycobacterial dihydrofolate reductase is the possible target of these compounds. 相似文献
27.
Jernej Jakse Natasa Stajner Zlata Luthar Jean-Marc Jeltsch Branka Javornik 《Molecular breeding : new strategies in plant improvement》2011,28(2):227-239
Data mining of gene sequences available from various projects dealing with the development of expressed sequence tags (ESTs)
can contribute to the discovery of new microsatellite markers. Our aim was to develop new microsatellite markers in hop isolated
from an enriched cDNA library and from coding GenBank sequences and to test their suitability in hop diversity studies and
for construction of a linkage map. In a set of 614 coding GenBank sequences, 72 containing microsatellites were found (11.7%);
the most frequent were trinucleotide repeats (54.0%) followed by dinucleotide repeats (34.5%). Additionally, 11 sequences
containing microsatellites were isolated from an enriched cDNA library. A total of 34 primer pairs were designed, 29 based
on GenBank sequences and five on sequences from the cDNA enriched library. Twenty-seven (79.4%) coding microsatellites were
successfully amplified and used in diversity and linkage mapping studies. Eleven primer pairs amplified 12 coding microsatellite
loci suitable for mapping and were placed on female and male linkage maps. We were able to extend previous simple sequence
repeat (SSR) female, male and integral maps by 38.8, 25.8 and 40.0 cM, respectively. In the diversity study, 36 diverse hop
genotypes were analyzed. Twenty-four coding microsatellites were polymorphic, 17 showing co-dominant behavior and 7 primer
pairs amplifying three or more bands in some hop genotypes. Altogether, 143 microsatellite DNA fragments were amplified and
they revealed a clear separation of hop genotypes according to geographical region, use or breeding history. In addition,
a discussion and comparison of results with other plant coding/EST SSR studies is presented. Our results showed that these
microsatellite markers can enhance hop diversity and linkage mapping studies and are a comparable marker system to non-coding
SSRs. 相似文献
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Skoko N Vujovic J Savic M Papic N Vasiljevic B Ljubijankic G 《Journal of microbiological methods》2005,61(1):137-140
The screening of microbial natural products continues to represent an important route to the discovery of novel chemicals for development of new therapeutic agents. The aim of this work was to develop an efficient method for the detection of immunosuppressive compounds produced by soil actinomycetes. Mutant strain of Saccharomyces cerevisiae, named FAV20, sensitive to FK506 was constructed by disrupting VMA22 gene using the selectable marker kanMX4 which allowed detection of integration events. Actinomycetes were isolated from different soil samples and in a newly developed test with S. cerevisiae FAV20, six strains have been identified that produce bioactive compounds with the same mechanism of action as FK506. S. cerevisiae FAV20 can be easily used as a test strain in drug screening programs based on inhibition of the calcineurin phosphatase dependent signaling pathway in the cell. 相似文献
30.
Haloarchaeal diversity in the crystallizers of Adriatic Secovlje salterns was investigated using gene fragments encoding 16S rRNA and bacteriorhodopsin as molecular markers. Screening of 180 clones from five gene libraries constructed for each gene targeted revealed 15 different 16S rRNA and 10 different bacteriorhodopsin phylotypes, indicating higher haloarchaeal diversity than previously reported in such hypersaline environments. Furthermore, results of rarefaction analysis indicated that analysis of an increasing number of clones would have revealed additional diversity. Finally, most sequences from the crystallizers grouped within the Halorubrum branch, whereas square-shaped 'Haloquadratum' relatives, repeatedly reported to dominate crystallizer communities, were rare. Presence of such special and diverse haloarchaeal community could be attributed to the Secovlje salterns rare continuous short-cycling salt production mechanism. 相似文献