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91.
Wevers D Metzger S Babweteera F Bieberbach M Boesch C Cameron K Couacy-Hymann E Cranfield M Gray M Harris LA Head J Jeffery K Knauf S Lankester F Leendertz SA Lonsdorf E Mugisha L Nitsche A Reed P Robbins M Travis DA Zommers Z Leendertz FH Ehlers B 《Journal of virology》2011,85(20):10774-10784
Adenoviruses (AdVs) broadly infect vertebrate hosts, including a variety of nonhuman primates (NHPs). In the present study, we identified AdVs in NHPs living in their natural habitats, and through the combination of phylogenetic analyses and information on the habitats and epidemiological settings, we detected possible horizontal transmission events between NHPs and humans. Wild NHPs were analyzed with a pan-primate AdV-specific PCR using a degenerate nested primer set that targets the highly conserved adenovirus DNA polymerase gene. A plethora of novel AdV sequences were identified, representing at least 45 distinct AdVs. From the AdV-positive individuals, 29 nearly complete hexon genes were amplified and, based on phylogenetic analysis, tentatively allocated to all known human AdV species (Human adenovirus A to Human adenovirus G [HAdV-A to -G]) as well as to the only simian AdV species (Simian adenovirus A [SAdV-A]). Interestingly, five of the AdVs detected in great apes grouped into the HAdV-A, HAdV-D, HAdV-F, or SAdV-A clade. Furthermore, we report the first detection of AdVs in New World monkeys, clustering at the base of the primate AdV evolutionary tree. Most notably, six chimpanzee AdVs of species HAdV-A to HAdV-F revealed a remarkably close relationship to human AdVs, possibly indicating recent interspecies transmission events. 相似文献
92.
Alba Casellas Cristina Mallol Ariana Salavert Veronica Jimenez Miquel Garcia Judith Agudo Mercè Obach Virginia Haurigot Laia Vilà Maria Molas Ricardo Lage Meritxell Morró Estefania Casana Jesús Ruberte Fatima Bosch 《The Journal of biological chemistry》2015,290(27):16772-16785
The human insulin-like growth factor 2 (IGF2) and insulin genes are located within the same genomic region. Although human genomic studies have demonstrated associations between diabetes and the insulin/IGF2 locus or the IGF2 mRNA-binding protein 2 (IGF2BP2), the role of IGF2 in diabetes pathogenesis is not fully understood. We previously described that transgenic mice overexpressing IGF2 specifically in β-cells (Tg-IGF2) develop a pre-diabetic state. Here, we characterized the effects of IGF2 on β-cell functionality. Overexpression of IGF2 led to β-cell dedifferentiation and endoplasmic reticulum stress causing islet dysfunction in vivo. Both adenovirus-mediated overexpression of IGF2 and treatment of adult wild-type islets with recombinant IGF2 in vitro further confirmed the direct implication of IGF2 on β-cell dysfunction. Treatment of Tg-IGF2 mice with subdiabetogenic doses of streptozotocin or crossing these mice with a transgenic model of islet lymphocytic infiltration promoted the development of overt diabetes, suggesting that IGF2 makes islets more susceptible to β-cell damage and immune attack. These results indicate that increased local levels of IGF2 in pancreatic islets may predispose to the onset of diabetes. This study unravels an unprecedented role of IGF2 on β-cells function. 相似文献
93.
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95.
Integrated analysis of established and novel microbial and chemical methods for microbial source tracking 总被引:1,自引:0,他引:1
Blanch AR Belanche-Muñoz L Bonjoch X Ebdon J Gantzer C Lucena F Ottoson J Kourtis C Iversen A Kühn I Mocé L Muniesa M Schwartzbrod J Skraber S Papageorgiou GT Taylor H Wallis J Jofre J 《Applied and environmental microbiology》2006,72(9):5915-5926
Several microbes and chemicals have been considered as potential tracers to identify fecal sources in the environment. However, to date, no one approach has been shown to accurately identify the origins of fecal pollution in aquatic environments. In this multilaboratory study, different microbial and chemical indicators were analyzed in order to distinguish human fecal sources from nonhuman fecal sources using wastewaters and slurries from diverse geographical areas within Europe. Twenty-six parameters, which were later combined to form derived variables for statistical analyses, were obtained by performing methods that were achievable in all the participant laboratories: enumeration of fecal coliform bacteria, enterococci, clostridia, somatic coliphages, F-specific RNA phages, bacteriophages infecting Bacteroides fragilis RYC2056 and Bacteroides thetaiotaomicron GA17, and total and sorbitol-fermenting bifidobacteria; genotyping of F-specific RNA phages; biochemical phenotyping of fecal coliform bacteria and enterococci using miniaturized tests; specific detection of Bifidobacterium adolescentis and Bifidobacterium dentium; and measurement of four fecal sterols. A number of potentially useful source indicators were detected (bacteriophages infecting B. thetaiotaomicron, certain genotypes of F-specific bacteriophages, sorbitol-fermenting bifidobacteria, 24-ethylcoprostanol, and epycoprostanol), although no one source identifier alone provided 100% correct classification of the fecal source. Subsequently, 38 variables (both single and derived) were defined from the measured microbial and chemical parameters in order to find the best subset of variables to develop predictive models using the lowest possible number of measured parameters. To this end, several statistical or machine learning methods were evaluated and provided two successful predictive models based on just two variables, giving 100% correct classification: the ratio of the densities of somatic coliphages and phages infecting Bacteroides thetaiotaomicron to the density of somatic coliphages and the ratio of the densities of fecal coliform bacteria and phages infecting Bacteroides thetaiotaomicron to the density of fecal coliform bacteria. Other models with high rates of correct classification were developed, but in these cases, higher numbers of variables were required. 相似文献
96.
Molecular model of the outward facing state of the human multidrug resistance protein 4 (MRP4/ABCC4)
ATP-binding cassette (ABC) transporter multidrug resistance protein 4 (MRP4, ABCC4) is involved in multidrug resistance (MDR), which is an increasing challenge to the treatment of cancer and infections. We have constructed a molecular model of ABCC4 based on the outward facing Sav1866 crystal structure using molecular modeling techniques. Amino acids reported by ICMPocketFinder to take part in substrate translocation were among others Glu103 (TMH1), Ser328 (TMH5), Gly359 (TMH6), Arg362 (TMH6), Val726 (TMH7), and Leu987 (TMH12), and their corresponding amino acids in ABCB1 (P-glycoprotein) have been reported to be involved in drug binding according to site-directed mutagenesis studies. The ABCC4 model may be used as a working tool for experimental studies on ABCC4 and design of more specific membrane transport modulating agents (MTMA). 相似文献
97.
Mavel S Vercouillie J Garreau L Raguza T Ravna AW Chalon S Guilloteau D Emond P 《Bioorganic & medicinal chemistry》2008,16(19):9050-9055
In order to predict affinity of new diphenylsulfides for the serotonin transporter (SERT), a molecular modeling model was used to compare potential binding affinity of new compounds with known potent ligands. The aim of this study is to identify a suitable PET radioligand for imaging the SERT, new derivatives, and their precursors for a C-11 or F-18 radiolabeling, were synthesized. Two fluorinated derivatives displayed good in vitro affinity for the SERT (K(i)=14.3+/-1 and 10.1+/-2.7 nM) and good selectivity toward the other monoamine transporters as predicted by the docking study. 相似文献
98.
Casellas J Varona L Muñoz G Ramírez O Barragán C Tomás A Martínez-Giner M Ovilo C Sánchez A Noguera JL Rodríguez MC 《Animal : an international journal of animal bioscience》2008,2(2):177-183
The aim of this study was to investigate chromosomal regions affecting gestation length in sows. An experimental F2 cross between Iberian and Meishan pig breeds was used for this purpose and we genotyped 119 markers covering the 18 porcine autosomal chromosomes. Within this context, we have developed a new empirical Bayes factor (BF) approach to compare between nested models, with and without the quantitative trait loci (QTL) effect, and after including the location of the QTL as an unknown parameter in the model. This empirical BF can be easily calculated from the output of a Markov chain Monte Carlo sampling by averaging conditional densities at the null QTL effects. Linkage analyses were performed in each chromosome using an animal model to account for infinitesimal genetic effects. Initially, three QTL were detected at chromosomes 6, 8 and 11 although, after correcting for multiple testing, only the additive QTL located in cM 110 of chromosome 8 remained. For this QTL, the allelic effect of substitution of the Iberian allele increased gestation length in 0.521 days, with a highest posterior density region at 95% ranged between 0.121 and 0.972 days. Although future studies are necessary to confirm if detected QTL is relevant and segregating in commercial pig populations, a hot-spot on the genetic regulation of gestation length in pigs seems to be located in chromosome 8. 相似文献
99.
Gabriella Aina Gianluca Nasini Orso Vajna de Pava 《Journal of Molecular Catalysis .B, Enzymatic》2001,11(4-6):367-371
The synthesis of racemic 5,6,7,8-tetrahydro-8-methyl-1,3-dimethoxynaphthalen-6-one 1 was performed and the bioreduction to the corresponding β-tetralols was studied with respect to the stereochemical course and optical purity of the products; in particular the 6S,8S enantiomer corresponding to the dimethyl derivative of the natural compound feroxidin was isolated. The biomass of: Aspergillus niger, Cladosporium cladosporioides, Candida lypolitica, Bacillus megatherium, Rhodotorula minuta, R. flava, R. rubra, Beauveria bassiana and Baker's yeast were used as biocatalysts. Relative and absolute configurations of the obtained β-tetralols were established by comparison with those of the natural feroxidin. 相似文献
100.