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101.
Elizabeth L. Turner Siham Sikander Omer Bangash Ahmed Zaidi Lisa Bates John Gallis Nima Ganga Karen O’Donnell Atif Rahman Joanna Maselko 《Trials》2016,17(1)
BackgroundThe negative effects of perinatal depression on the mother and child start early and persist throughout the lifecourse (Lancet 369(9556):145–57, 2007; Am J Psychiatry 159(1):43-7, 2002; Arch Dis Child 77(2):99–101, 1997; J Pak Med Assoc 60(4):329; J Psychosoma Res 49(3):207–16, 2000; Clin Child Fam Psychol Rev 14(1):1–27, 2011). Given that 10–35 % of children worldwide are exposed to perinatal depression in their first year of life (Int Rev Psychiatry 8(1):37–54, 1996), mitigating this intergenerational risk is a global public health priority (Perspect Public Health 129(5):221–7, 2009; Trop Med Int Health 13(4):579–83, 2008; Br Med Bull 101(1):57–79, 2012). However, it is not clear whether intervention with depressed women can have long-term benefits for the mother and/or her child. We describe a study of the effectiveness of a peer-delivered depression intervention delivered through 36 postnatal months, the Thinking Healthy Program Peer-delivered PLUS (THPP+) for women and their children in rural Pakistan.Methods/designThe THPP+ study aims are: (1) to evaluate the effects of an extended 36-month perinatal depression intervention on maternal and index child outcomes using a cluster randomized controlled trial (c-RCT) and (2) to determine whether outcomes among index children of perinatally depressed women in the intervention arm converge with those of index children born to perinatally nondepressed women. The trial is designed to recruit 560 pregnant women who screened positive for perinatal depression (PHQ-9 score ≥10) from 40 village clusters, of which 20 receive the THPP+ intervention. An additional reference group consists of 560 perinatally nondepressed women from the same 40 clusters as the THPP+ trial. The women in the nondepressed group are not targeted to receive the THPP+ intervention; but, by recruiting pregnant women from both intervention and control clusters, we are able to evaluate any carryover effects of the THPP+ intervention on the women and their children. Perinatally depressed women in the THPP+ intervention arm receive bimonthly group-based sessions. Primary outcomes are 3-year maternal depression and 3-year child development indicators. Analyses are intention-to-treat and account for the clustered design.DiscussionThis trial, together with the reference group, has the potential to further our understanding of the early developmental lifecourse of children of both perinatally depressed and perinatally nondepressed women in rural Pakistan and to determine whether intervening with women’s depression in the perinatal period can mitigate the negative effects of maternal depression on 36-month child development.
Trial registration
THPP-P ClinicalTrials.gov Identifier: (registered on 9 April 2014).THPP+ ClinicalTrials.gov Identifier: NCT02111915 (registered on 21 January 2016).Sponsor: Human Development Research Foundation (HDRF). NCT02658994Electronic supplementary material
The online version of this article (doi:10.1186/s13063-016-1530-y) contains supplementary material, which is available to authorized users. 相似文献102.
Signaling through integrin LFA-1 leads to filamentous actin polymerization and remodeling,resulting in enhanced T cell adhesion 总被引:7,自引:0,他引:7
Porter JC Bracke M Smith A Davies D Hogg N 《Journal of immunology (Baltimore, Md. : 1950)》2002,168(12):6330-6335
The integrins can activate signaling pathways, but the final downstream outcome of these pathways is often unclear. This study analyzes the consequences of signaling events initiated by the interaction of the leukocyte integrin LFA-1 with its ligand, dimeric ICAM-1. We show that the active form of LFA-1 regulates its own function on primary human T cells by directing the remodeling of the F-actin cytoskeleton to strengthen T cell adhesion to ICAM-1. Confocal microscopy revealed that both F-actin bundling and overall levels of F-actin are increased in the ICAM-1-adhering T cells. This increase in F-actin levels and change in F-actin distribution was quantitated for large numbers of T cells using the technique of laser scanning cytometry and was found to be significant. The study went on to show that clustering of conformationally altered LFA-1 is essential for the changes in F-actin, and a model is proposed in which clustered, high-avidity T cell LFA-1, interacting with multivalent ICAM-1, causes LFA-1 signaling, which results in F-actin polymerization and higher-order F-actin bundling. The findings demonstrate that LFA-1 acts not only as an adhesion receptor but also as a signaling receptor by actively initiating the F-actin reorganization that is essential for many T cell-dependent processes. 相似文献
103.
104.
The formation of proper structural disulfide bonds is one of the key steps during the folding of many secretory proteins and occurs both in prokaryotes and eukaryotes. In Gram negative bacterium Escherichia coli this process is catalyzed by a set of periplasmic oxidoreductases, termed Dsb. These proteins function in two separate pathways: (1) oxidizing (DsbA/DsbB system), responsible for introducing S-S bonds, and (2) reducing (DsbC/DsbD system, DsbG, CcmG and CcmH) which acts to isomerase wrongly formed disulfide bonds and participates in maturation of cytochrome c. The first system acts in connection with the inner membrane electron transfer system, using quinone molecules as electron acceptors, whereas reducing pathway relies on constant supply of electrons provided by the cytoplasmic thioredoxin system. Majority of Dsb proteins belongs to the thioredoxin superfamily and they contain the conserved Cys-X-X-Cys motif in their active site. The redox properties of Dsb proteins with the particular focus on structure-function dependence are in this review discussed. 相似文献
105.
Zylicz-Stachula A Zołnierkiewicz O Jeżewska-Frąckowiak J Skowron PM 《BioTechniques》2011,50(6):397-406
The type IIS/IIC restriction endonuclease TspGWI recognizes the sequence 5'-ACGGA-3', cleaving DNA 11/9 nucleotides downstream. Here we show that sinefungin, a cofactor analog of S-adenosyl methionine, induces a unique type of relaxation in DNA recognition specificity. In the presence of sinefungin, TspGWI recognizes and cleaves at least 12 degenerate variants of the original recognition sequence that vary by single base pair changes from the original 5-bp restriction site with only a single degeneracy per variant appearing to be allowed. In addition, sinefungin was found to have a stimulatory effect on cleavage at these nondegenerate TspGWI recognition sites, irrespective of their number or the DNA topology. Interestingly, no fixed "core" could be identified among the new recognition sequences. Theoretically, TspGWI cleaves DNA every 1024 bp, while sinefungin-induced activity cleaves every 78.8 bp, corresponding to a putative 3-bp long recognition site. Thus, the combination of sinefungin and TspGWI represents a novel frequent cutter, next only to CviJI/CviJI*, that should prove useful in DNA cloning methodologies. 相似文献
106.
Mayer KF Martis M Hedley PE Simková H Liu H Morris JA Steuernagel B Taudien S Roessner S Gundlach H Kubaláková M Suchánková P Murat F Felder M Nussbaumer T Graner A Salse J Endo T Sakai H Tanaka T Itoh T Sato K Platzer M Matsumoto T Scholz U Dolezel J Waugh R Stein N 《The Plant cell》2011,23(4):1249-1263
We used a novel approach that incorporated chromosome sorting, next-generation sequencing, array hybridization, and systematic exploitation of conserved synteny with model grasses to assign ~86% of the estimated ~32,000 barley (Hordeum vulgare) genes to individual chromosome arms. Using a series of bioinformatically constructed genome zippers that integrate gene indices of rice (Oryza sativa), sorghum (Sorghum bicolor), and Brachypodium distachyon in a conserved synteny model, we were able to assemble 21,766 barley genes in a putative linear order. We show that the barley (H) genome displays a mosaic of structural similarity to hexaploid bread wheat (Triticum aestivum) A, B, and D subgenomes and that orthologous genes in different grasses exhibit signatures of positive selection in different lineages. We present an ordered, information-rich scaffold of the barley genome that provides a valuable and robust framework for the development of novel strategies in cereal breeding. 相似文献
107.
Frances M. Cowan Sibongile Mtetwa Calum Davey Elizabeth Fearon Jeffrey Dirawo Ramona Wong-Gruenwald Theresa Ndikudze Samson Chidiya Clemens Benedikt Joanna Busza James R. Hargreaves 《PloS one》2013,8(10)
Objective(S)
To determine the HIV prevalence and extent of engagement with HIV prevention and care among a representative sample of Zimbabwean sex workers working in Victoria Falls, Hwange and Mutare.Design
Respondent driven sampling (RDS) surveys conducted at each site.Methods
Sex workers were recruited using respondent driven sampling with each respondent limited to recruiting 2 peers. Participants completed an interviewer-administered questionnaire and provided a finger prick blood sample for HIV antibody testing. Statistical analysis took account of sampling method.Results
870 women were recruited from the three sites. HIV prevalence was between 50 and 70%. Around half of those confirmed HIV positive were aware of their HIV status and of those 50-70% reported being enrolled in HIV care programmes. Overall only 25-35% of those with laboratory-confirmed HIV were accessing antiretroviral therapy. Among those reporting they were HIV negative, 21-28% reported having an HIV test in the last 6 months. Of those tested HIV negative, most (65-82%) were unaware of their status. Around two-thirds of sex workers reported consistent condom use with their clients. As in other settings, sex workers reported high rates of gender based violence and police harassment.Conclusions
This survey suggests that prevalence of HIV is high among sex workers in Zimbabwe and that their engagement with prevention, treatment and care is sub-optimal. Intensifying prevention and care interventions for sex workers has the potential to markedly reduce HIV and social risks for sex workers, their clients and the general population in Zimbabwe and elsewhere in the region. 相似文献108.
Joanna L Dixon Stephanie Sargeant Philip D Nightingale J Colin Murrell 《The ISME journal》2013,7(3):568-580
Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling waters of up to 0.117±0.002 d−1 (∼10 nmol l−1 d−1). On average, coastal upwelling waters were 11 times greater than open ocean northern temperate (NT) waters, eight times greater than gyre waters and four times greater than equatorial upwelling (EU) waters; suggesting that all upwelling waters upon reaching the surface (⩽20 m), contain a microbial population that uses a relatively high amount of carbon (0.3–10 nmol l−1 d−1), derived from methanol, to support their growth. In open ocean Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04–0.68 nmol l−1 d−1. Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre waters. Several methylotrophic bacterial species were identified from open ocean Atlantic waters using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling waters between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air–sea exchange scientists. 相似文献
109.
Joanna R. Vondrasek 《Journal of avian biology》2006,37(1):52-57
Social factors, such as the duration of territorial occupancy or of time paired with a mate can affect the rate at which individual birds sing. This study examined the influence of duration of pair‐bond and territory occupancy as well as date on the rate of singing by male and female northern cardinals Cardinalis cardinalis. When differences in breeding status were controlled, female cardinals sang at higher rates earlier in the season. Females in newly formed pairs sang at significantly higher rates than those in pairs that had previously bred together. In contrast, male cardinals did not show significant variation in the rate of singing throughout the season. The song rates of males in newly formed and established pairs did not differ significantly. Song rates for males and females in mated pairs were not significantly correlated. This study suggests that social factors have a strong effect on the rate at which female cardinals sing. It is possible that increased intra‐sexual aggression by females when they are establishing a new territory with a new mate leads to this higher level of song output. Once females have established a territory and acquired a mate, dear‐enemy effects might diminish the need for acoustic territorial defence. Differences in the constraints of nesting or the attraction of extra‐pair mates might explain the sexual differences in male and female singing behaviour. 相似文献
110.
Simon N. Haydar Chiara Ghiron Laura Bettinetti Hendrick Bothmann Thomas A. Comery John Dunlop Salvatore La Rosa Iolanda Micco Martina Pollastrini Joanna Quinn Renza Roncarati Carla Scali Michela Valacchi Maurizio Varrone Riccardo Zanaletti 《Bioorganic & medicinal chemistry》2009,17(14):5247-5258
Alpha 7 nicotinic acetylcholine receptor (α7 nAChR) agonists are promising therapeutic candidates for the treatment of cognitive impairment associated with a variety of disorders including Alzheimer’s disease and schizophrenia. Alpha 7 nAChRs are expressed in brain regions associated with cognitive function, regulate cholinergic neurotransmission and have been shown to be down regulated in both schizophrenia and Alzheimer’s disease. Herein we report a novel, potent small molecule agonist of the alpha 7 nAChR, SEN12333/WAY-317538. This compound is a selective agonist of the α7 nAChR with excellent in vitro and in vivo profiles, excellent brain penetration and oral bioavailability, and demonstrates in vivo efficacy in multiple behavioural cognition models. The SAR and biological evaluation of this series of compounds are discussed. 相似文献