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991.
Mélodie-Anne Drouin Richard Fleet Julien Poitras Patrick Archambault Jean-Marc Chauny Jean-Frédéric Lévesque Mathieu Ouimet Gilles Dupuis Alain Tanguay Geneviève Simard-Racine Josée Gauthier Fatoumata Korika Tounkara Marie-Hélène Gilbert France Légaré 《PloS one》2015,10(4)
Introduction
Health services research generates useful knowledge. Promotion of implementation of this knowledge in medical practice is essential. Prior to initiation of a major study on rural emergency departments (EDs), we deployed two knowledge transfer strategies designed to generate interest and engagement from potential knowledge users. The objective of this paper was to review: 1) a combined project launch and media press release strategy, and 2) a pre-study survey designed to survey potential knowledge users’ opinions on the proposed study variables.Materials and Methods
We evaluated the impact of the project launch (presentation at two conferences hosted by key stakeholders) and media press release via a survey of participants/stakeholders and by calculating the number of media interview requests and reports generated. We used a pre-study survey to collect potential key stakeholder’ opinions on the study variables.Results
Twenty-one of Quebec’s 26 rural EDs participated in the pre-study survey (81% participation rate). The press release about the study generated 51 press articles and 20 media request for interviews, and contributed to public awareness of a major rural research initiative. In the pre-study survey, thirteen participants (46%) mentioned prior knowledge of the research project. Results from the pre-study survey revealed that all of the potential study variables were considered to be relevant for inclusion in the research project. Respondents also proposed additional variables of interest, including factors promoting retention of human resources.Conclusions
The present study demonstrated the potential utility of a two-pronged knowledge transfer strategy, including a combined formal launch and press release, and a pre-study survey designed to ensure that the included variables were of interest to participants and stakeholders. 相似文献992.
Anna Przytulska Maciej Bartosiewicz Milla Rautio France Dufresne Warwick F. Vincent 《PloS one》2015,10(5)
Climate change is proceeding rapidly at high northern latitudes and may have a variety of direct and indirect effects on aquatic food webs. One predicted effect is the potential shift in phytoplankton community structure towards increased cyanobacterial abundance. Given that cyanobacteria are known to be a nutritionally poor food source, we hypothesized that such a shift would reduce the efficiency of feeding and growth of northern zooplankton. To test this hypothesis, we first isolated a clone of Daphnia pulex from a permafrost thaw pond in subarctic Québec, and confirmed that it was triploid but otherwise genetically similar to a diploid, reference clone of the same species isolated from a freshwater pond in southern Québec. We used a controlled flow-through system to investigate the direct effect of temperature and indirect effect of subarctic picocyanobacteria (Synechococcus) on threshold food concentrations and growth rate of the high latitude clone. We also compared the direct effect of temperature on both Daphnia clones feeding on eukaryotic picoplankton (Nannochloropsis). The high latitude clone had a significantly lower food threshold for growth than the temperate clone at both 18 and 26°C, implying adaptation to lower food availability even under warmer conditions. Polyunsaturated fatty acids were present in the picoeukaryote but not the cyanobacterium, confirming the large difference in food quality. The food threshold for growth of the high latitude Daphnia was 3.7 (18°C) to 4.2 (26°C) times higher when fed Synechococcus versus Nannochloropsis, and there was also a significant negative effect of increased temperature and cyanobacterial food on zooplankton fatty acid content and composition. The combined effect of temperature and food quality on the performance of the high latitude Daphnia was greater than their effects added separately, further indicating the potentially strong indirect effects of climate warming on aquatic food web processes. 相似文献
993.
Sophie Bertrand Guillaume De Lamine de Bex Christa Wildemauwe Octavie Lunguya Marie France Phoba Benedikt Ley Jan Jacobs Raymond Vanhoof Wesley Mattheus 《PloS one》2015,10(2)
Surveillance of Salmonella enterica subsp. enterica serovar Enteritidis is generally considered to benefit from molecular techniques like multiple-locus variable-number of tandem repeats analysis (MLVA), which allow early detection and confinement of outbreaks. Here, a surveillance study, including phage typing, antimicrobial susceptibility testing and MLVA on 1,535 S. Enteritidis isolates collected between 2007 and 2012, was used to evaluate the added value of MLVA for public health surveillance in Belgium. Phage types PT4, PT8, PT21, PT1, PT6, PT14b, PT28 and PT13 dominate the Belgian S. Enteritidis population. The isolates of S. Enteritidis were most frequently susceptible to all antibiotics tested. 172 different MLVA profiles were detected, of which 9 frequent profiles included 67.2% of the S. Enteritidis population. During a serial passage experiment on selected isolates to investigate the in vitro stability of the 5 MLVA loci, no variations over time were observed indicating that the MLVA profiles were stable. The MLVA profile of isolates originating from different outbreaks in the Democratic Republic of the Congo (DRC) between 2010 and 2011 were distinct from any of the MLVA profiles found in Belgian isolates throughout the six year observational period and demonstrates that MLVA improves public health surveillance of S. Enteritidis. However, MLVA should be complemented with other subtyping methods when investigating outbreaks is caused by the most common MLVA profile. 相似文献
994.
Is drug insurance status an effect modifier in epidemiologic database studies? The case of maternal asthma and major congenital malformations
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995.
Carl H. Coleman Chantal Ardiot Sverine Blesson Yves Bonnin Francois Bompart Pierre Colonna Ames Dhai Julius Ecuru Andrew Edielu Christian Herv Franois Hirsch Bocar Kouyat Marie‐France Mamzer‐Bruneel Dionko Maound Eric Martinent Honor Ntsiba Grard Pel Gilles Quva Marie‐Christine Reinmund Samba Cor Sarr Abdoulaye Sepou Antoine Tarral Djetodjide Tetimian Olaf Valverde Simon Van Nieuwenhove Nathalie Strub‐Wourgaft 《Developing world bioethics》2015,15(3):241-247
Developing countries face numerous barriers to conducting effective and efficient ethics reviews of international collaborative research. In addition to potentially overlooking important scientific and ethical considerations, inadequate or insufficiently trained ethics committees may insist on unwarranted changes to protocols that can impair a study's scientific or ethical validity. Moreover, poorly functioning review systems can impose substantial delays on the commencement of research, which needlessly undermine the development of new interventions for urgent medical needs. In response to these concerns, the Drugs for Neglected Diseases Initiative (DNDi), an independent nonprofit organization founded by a coalition of public sector and international organizations, developed a mechanism to facilitate more effective and efficient host country ethics review for a study of the use of fexinidazole for the treatment of late stage African Trypanosomiasis (HAT). The project involved the implementation of a novel ‘pre‐review’ process of ethical oversight, conducted by an ad hoc committee of ethics committee representatives from African and European countries, in collaboration with internationally recognized scientific experts. This article examines the process and outcomes of this collaborative process. 相似文献
996.
997.
E Pante J Abdelkrim A Viricel D Gey S C France M C Boisselier S Samadi 《Heredity》2015,114(5):450-459
RAD-tag sequencing is a promising method for conducting genome-wide evolutionary studies. However, to date, only a handful of studies empirically tested its applicability above the species level. In this communication, we use RAD tags to contribute to the delimitation of species within a diverse genus of deep-sea octocorals, Chrysogorgia, for which few classical genetic markers have proved informative. Previous studies have hypothesized that single mitochondrial haplotypes can be used to delimit Chrysogorgia species. On the basis of two lanes of Illumina sequencing, we inferred phylogenetic relationships among 12 putative species that were delimited using mitochondrial data, comparing two RAD analysis pipelines (Stacks and PyRAD). The number of homologous RAD loci decreased dramatically with increasing divergence, as >70% of loci are lost when comparing specimens separated by two mutations on the 700-nt long mitochondrial phylogeny. Species delimitation hypotheses based on the mitochondrial mtMutS gene are largely supported, as six out of nine putative species represented by more than one colony were recovered as discrete, well-supported clades. Significant genetic structure (correlating with geography) was detected within one putative species, suggesting that individuals characterized by the same mtMutS haplotype may belong to distinct species. Conversely, three mtMutS haplotypes formed one well-supported clade within which no population structure was detected, also suggesting that intraspecific variation exists at mtMutS in Chrysogorgia. Despite an impressive decrease in the number of homologous loci across clades, RAD data helped us to fine-tune our interpretations of classical mitochondrial markers used in octocoral species delimitation, and discover previously undetected diversity. 相似文献
998.
999.
Susannah M. L. Gagnon Peter J. Meloncelli Ruixiang B. Zheng Omid Haji-Ghassemi Asha R. Johal Svetlana N. Borisova Todd L. Lowary Stephen V. Evans 《The Journal of biological chemistry》2015,290(45):27040-27052
Homologous glycosyltransferases α-(1→3)-N-acetylgalactosaminyltransferase (GTA) and α-(1→3)-galactosyltransferase (GTB) catalyze the final step in ABO(H) blood group A and B antigen synthesis through sugar transfer from activated donor to the H antigen acceptor. These enzymes have a GT-A fold type with characteristic mobile polypeptide loops that cover the active site upon substrate binding and, despite intense investigation, many aspects of substrate specificity and catalysis remain unclear. The structures of GTA, GTB, and their chimeras have been determined to between 1.55 and 1.39 Å resolution in complex with natural donors UDP-Gal, UDP-Glc and, in an attempt to overcome one of the common problems associated with three-dimensional studies, the non-hydrolyzable donor analog UDP-phosphono-galactose (UDP-C-Gal). Whereas the uracil moieties of the donors are observed to maintain a constant location, the sugar moieties lie in four distinct conformations, varying from extended to the “tucked under” conformation associated with catalysis, each stabilized by different hydrogen bonding partners with the enzyme. Further, several structures show clear evidence that the donor sugar is disordered over two of the observed conformations and so provide evidence for stepwise insertion into the active site. Although the natural donors can both assume the tucked under conformation in complex with enzyme, UDP-C-Gal cannot. Whereas UDP-C-Gal was designed to be “isosteric” with natural donor, the small differences in structure imposed by changing the epimeric oxygen atom to carbon appear to render the enzyme incapable of binding the analog in the active conformation and so preclude its use as a substrate mimic in GTA and GTB. 相似文献
1000.
Hu J Gagnon KT Liu J Watts JK Syeda-Nawaz J Bennett CF Swayze EE Randolph J Chattopadhyaya J Corey DR 《Biological chemistry》2011,392(4):315-325
Spinocerebellar ataxia-3 (also known as Machado-Joseph disease) is an incurable neurodegenerative disorder caused by expression of a mutant variant of ataxin-3 (ATX3) protein. Inhibiting expression of ATX3 would provide a therapeutic strategy, but indiscriminant inhibition of both wild-type and mutant ATX3 might lead to undesirable side effects. An ideal silencing agent would block expression of mutant ATX3 while leaving expression of wild-type ATX3 intact. We have previously observed that peptide nucleic acid (PNA) conjugates targeting the expanded CAG repeat within ATX3 mRNA block expression of both alleles. We have now identified additional PNAs capable of inhibiting ATX3 expression that vary in length and in the nature of the conjugated cation chain. We can also achieve potent and selective inhibition using duplex RNAs containing one or more mismatches relative to the CAG repeat. Anti-CAG antisense bridged nucleic acid oligonucleotides that lack a cationic domain are potent inhibitors but are not allele-selective. Allele-selective inhibitors of ATX3 expression provide insights into the mechanism of selectivity and promising lead compounds for further development and in vivo investigation. 相似文献