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821.
Kubinyi E Vas J Hejjas K Ronai Z Brúder I Turcsán B Sasvari-Szekely M Miklósi A 《PloS one》2012,7(1):e30271
We investigated the association between repeat polymorphism in intron 4 of the tyrosine hydroxylase (TH) gene and two personality traits, activity-impulsivity and inattention, in German Shepherd Dogs. The behaviour of 104 dogs was characterized by two instruments: (1) the previously validated Dog-Attention Deficit Hyperactivity Disorder Rating Scale (Dog-ADHD RS) filled in by the dog owners and (2) the newly developed Activity-impulsivity Behavioural Scale (AIBS) containing four subtests, scored by the experimenters. Internal consistency, inter-observer reliability, test-retest reliability and convergent validity were demonstrated for AIBS.Dogs possessing at least one short allele were proved to be more active-impulsive by both instruments, compared to dogs carrying two copies of the long allele (activity-impulsivity scale of Dog-ADHD RS: p = 0.007; AIBS: p = 0.023). The results have some potential to support human studies; however, further research should reveal the molecular function of the TH gene variants, and look for the effect in more breeds. 相似文献
822.
Machado MV Ferreira DM Castro RE Silvestre AR Evangelista T Coutinho J Carepa F Costa A Rodrigues CM Cortez-Pinto H 《PloS one》2012,7(2):e31738
Introduction
Nonalcoholic fatty liver disease (NAFLD) can be seen as a manifestation of overnutrition. The muscle is a central player in the adaptation to energy overload, and there is an association between fatty-muscle and -liver. We aimed to correlate muscle morphology, mitochondrial function and insulin signaling with NAFLD severity in morbid obese patients.Methods
Liver and deltoid muscle biopsies were collected during bariatric surgery in NAFLD patients. NAFLD Activity Score and Younossi''s classification for nonalcoholic steatohepatitis (NASH) were applied to liver histology. Muscle evaluation included morphology studies, respiratory chain complex I to IV enzyme assays, and analysis of the insulin signaling cascade. A healthy lean control group was included for muscle morphology and mitochondrial function analyses.Results
Fifty one NAFLD patients were included of whom 43% had NASH. Intramyocellular lipids (IMCL) were associated with the presence of NASH (OR 12.5, p<0.001), progressive hepatic inflammation (p = 0.029) and fibrosis severity (p = 0.010). There was a trend to an association between IMCL and decreased Akt phosphorylation (p = 0.059), despite no association with insulin resistance. In turn, hepatic steatosis (p = 0.015) and inflammation (p = 0.013) were associated with decreased Akt phosphoryation. Citrate synthase activity was lower in obese patients (p = 0.047) whereas complex I (p = 0.040) and III (p = 0.036) activities were higher, compared with controls. Finally, in obese patients, complex I activity increased with progressive steatosis (p = 0.049) and with a trend with fibrosis severity (p = 0.056).Conclusions
In morbid obese patients, presence of IMCL associates with NASH and advanced fibrosis. Muscle mitochondrial dysfunction does not appear to be a major driving force contributing to muscle fat accumulation, insulin resistance or liver disease. Importantly, insulin resistance in muscle might occur at a late point in the insulin signaling cascade and be associated with IMCL and NAFLD severity. 相似文献823.
Rolo J Miragaia M Turlej-Rogacka A Empel J Bouchami O Faria NA Tavares A Hryniewicz W Fluit AC de Lencastre H;CONCORD Working Group 《PloS one》2012,7(4):e34768
Background
Several studies have addressed the epidemiology of community-associated Staphylococcus aureus (CA-SA) in Europe; nonetheless, a comprehensive perspective remains unclear. In this study, we aimed to describe the population structure of CA-SA and to shed light on the origin of methicillin-resistant S. aureus (MRSA) in this continent.Methods and Findings
A total of 568 colonization and infection isolates, comprising both MRSA and methicillin-susceptible S. aureus (MSSA), were recovered in 16 European countries, from community and community-onset infections. The genetic background of isolates was characterized by molecular typing techniques (spa typing, pulsed-field gel electrophoresis and multilocus sequence typing) and the presence of PVL and ACME was tested by PCR. MRSA were further characterized by SCCmec typing. We found that 59% of all isolates were associated with community-associated clones. Most MRSA were related with USA300 (ST8-IVa and variants) (40%), followed by the European clone (ST80-IVc and derivatives) (28%) and the Taiwan clone (ST59-IVa and related clonal types) (15%). A total of 83% of MRSA carried Panton-Valentine leukocidin (PVL) and 14% carried the arginine catabolic mobile element (ACME). Surprisingly, we found a high genetic diversity among MRSA clonal types (ST-SCCmec), Simpson’s index of diversity = 0.852 (0.788–0.916). Specifically, about half of the isolates carried novel associations between genetic background and SCCmec. Analysis by BURP showed that some CA-MSSA and CA-MRSA isolates were highly related, suggesting a probable local acquisition/loss of SCCmec.Conclusions
Our results imply that CA-MRSA origin, epidemiology and population structure in Europe is very dissimilar from that of USA. 相似文献824.
Guido M. Voets Tamara N. Platteel Ad C. Fluit Jelle Scharringa Claudia M. Schapendonk James Cohen Stuart Marc J. M. Bonten Maurine A. L. Hall National ESBL Surveillance Working Group 《PloS one》2012,7(12)
There is a global increase in infections caused by Enterobacteriaceae with plasmid-borne β-lactamases that confer resistance to third-generation cephalosporins. The epidemiology of these bacteria is not well understood, and was, therefore, investigated in a selection of 636 clinical Enterobacteriaceae with a minimal inhibitory concentration >1 mg/L for ceftazidime/ceftriaxone from a national survey (75% E. coli, 11% E. cloacae, 11% K. pneumoniae, 2% K. oxytoca, 2% P. mirabilis). Isolates were investigated for extended-spectrum β-lactamases (ESBLs) and ampC genes using microarray, PCR, gene sequencing and molecular straintyping (Diversilab and multi-locus sequence typing (MLST)). ESBL genes were demonstrated in 512 isolates (81%); of which 446 (87%) belonged to the CTX-M family. Among 314 randomly selected and sequenced isolates, bla
CTX-M-15 was most prevalent (n = 124, 39%), followed by bla
CTX-M-1 (n = 47, 15%), bla
CTX-M-14 (n = 15, 5%), bla
SHV-12 (n = 24, 8%) and bla
TEM-52 (n = 13, 4%). Among 181 isolates with MIC ≥16 mg/L for cefoxitin plasmid encoded AmpCs were detected in 32 and 27 were of the CMY-2 group. Among 102 E. coli isolates with MIC ≥16 mg/L for cefoxitin ampC promoter mutations were identified in 29 (28%). Based on Diversilab genotyping of 608 isolates (similarity cut-off >98%) discriminatory indices of bacteria with ESBL and/or ampC genes were 0.994, 0.985 and 0.994 for E. coli, K. pneumoniae and E. cloacae, respectively. Based on similarity cut-off >95% two large clusters of E. coli were apparent (of 43 and 30 isolates) and 21 of 21 that were typed by belonged to ST131 of which 13 contained bla
CTX-M-15. Our findings demonstrate that bla
CTX-M-15 is the most prevalent ESBL and we report a larger than previously reported prevalence of ampC genes among Enterobacteriaceae responsible for resistance to third-generation cephalosporins. 相似文献
825.
While extracting dynamics parameters from backbone (15)N relaxation measurements in proteins has become routine over the past two decades, it is increasingly recognized that accurate quantitative analysis can remain limited by the potential presence of systematic errors associated with the measurement of (15)N R(1) and R(2) or R(1ρ) relaxation rates as well as heteronuclear (15)N-{(1)H} NOE values. We show that systematic errors in such measurements can be far larger than the statistical error derived from either the observed signal-to-noise ratio, or from the reproducibility of the measurement. Unless special precautions are taken, the problem of systematic errors is shown to be particularly acute in perdeuterated systems, and even more so when TROSY instead of HSQC elements are used to read out the (15)N magnetization through the NMR-sensitive (1)H nucleus. A discussion of the most common sources of systematic errors is presented, as well as TROSY-based pulse schemes that appear free of systematic errors to the level of <1 %. Application to the small perdeuterated protein GB3, which yields exceptionally high S/N and therefore is an ideal test molecule for detection of systematic errors, yields relaxation rates that show considerably less residue by residue variation than previous measurements. Measured R(2)'/R(1)' ratios fit an axially symmetric diffusion tensor with a Pearson's correlation coefficient of 0.97, comparable to fits obtained for backbone amide RDCs to the Saupe matrix. 相似文献
826.
Gachomo EW Jimenez-Lopez JC Kayodé AP Baba-Moussa L Kotchoni SO 《Molecular biology reports》2012,39(4):4461-4469
Plant defensins represent a major innate immune protein superfamily with strong inhibitory effects on infectious diseases
of humans, antifungal/antibacterial activities, proteinase and insect amylase inhibitory activities. They are generally defined
by their conserved cysteine scaffold with α-helix and triple strand anti parallel β-sheet connected to the scaffold. With
the genome of more plant species being fully sequenced, significant information about newly sequenced defensin proteins has
been revealed. In this paper, we identify members of defensin protein families across plant species and use protein-modeling-based
structural reconstitution to reveal specific three dimensional hidden features of plant defensins mediating defense responses
and other interesting biological activities in plants. Our data revealed that plant defensins are structurally similar to
their insect counterparts despite the low amino acid sequence similarity between these two organisms. The molecular and structural
relationship among plant defensins and defensins from other species is discussed. 相似文献
827.
Fernanda Campanharo Favoreto Carlos Roberto Carvalho Andreia Barcelos Passos Lima Adésio Ferreira Wellington Ronildo Clarindo 《Plant Systematics and Evolution》2012,298(6):1185-1193
Flow cytometry (FCM) has been used to estimate the nuclear DNA content of Bromeliaceae species, which constitutes relevant information for studies of taxonomy, evolution, genetic diversity, and reproductive biology in bromeliads. Nevertheless, C values have only been estimated for 58 out of the 3,140 existing Bromeliaceae species. Aiming to contribute to the genome database of Bromeliaceae, the current study was carried out to measure the nuclear DNA content and base composition of Bromelioideae and Tillandsioideae species occurring in the Atlantic Rainforest. The most adequate FCM procedure provided histograms exhibiting G0/G1 peaks with coefficients of variation below 5%, so that these histograms were used to measure the mean 2C and AT% values for all collected Bromelioideae and Tillandsioideae species. These values were statistically compared, and dendrograms were plotted. A second comparison was performed among all mean 2C values reported for Pitcairnioideae, Tillandsioideae, and Bromelioideae species. In accordance with previous statistical comparisons, two groups were formed: cluster 1, composed by Tillandsia loliacea, Tillandsia usneoides, and Tillandsia cyanea, and cluster 2, gathering other 69 species. Based on these results, we concluded that FCM was a rapid, accurate, and reliable technique to assess genome size and base composition. Furthermore, the FCM data reported here will contribute to the Monocot and Bromeliaceae database, which still displays several ongoing gaps, especially for endemic species. 相似文献
828.
829.
Fluit Ad C. Bayjanov Jumamurat R. Aguilar María Díez Cantón Rafael Tunney Michael M. Elborn J. Stuart van Westreenen Mireille Ekkelenkamp Miquel B. 《Antonie van Leeuwenhoek》2021,114(10):1721-1733
Antonie van Leeuwenhoek - To improve understanding of the role of Ralstonia in cystic fibrosis (CF), whole genomes of 18 strains from clinical samples were sequenced using Illumina technology.... 相似文献