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R Hashim AM Khatib G Enwere JK Park R Reyburn M Ali NY Chang DR Kim B Ley K Thriemer AL Lopez JD Clemens JL Deen S Shin C Schaetti R Hutubessy MT Aguado MP Kieny D Sack S Obaro AJ Shaame SM Ali AA Saleh L von Seidlein MS Jiddawi 《PLoS neglected tropical diseases》2012,6(7):e1743
Introduction
Mass vaccinations are a main strategy in the deployment of oral cholera vaccines. Campaigns avoid giving vaccine to pregnant women because of the absence of safety data of the killed whole-cell oral cholera (rBS-WC) vaccine. Balancing this concern is the known higher risk of cholera and of complications of pregnancy should cholera occur in these women, as well as the lack of expected adverse events from a killed oral bacterial vaccine.Methodology/Principal Findings
From January to February 2009, a mass rBS-WC vaccination campaign of persons over two years of age was conducted in an urban and a rural area (population 51,151) in Zanzibar. Pregnant women were advised not to participate in the campaign. More than nine months after the last dose of the vaccine was administered, we visited all women between 15 and 50 years of age living in the study area. The outcome of pregnancies that were inadvertently exposed to at least one oral cholera vaccine dose and those that were not exposed was evaluated. 13,736 (94%) of the target women in the study site were interviewed. 1,151 (79%) of the 1,453 deliveries in 2009 occurred during the period when foetal exposure to the vaccine could have occurred. 955 (83%) out of these 1,151 mothers had not been vaccinated; the remaining 196 (17%) mothers had received at least one dose of the oral cholera vaccine. There were no statistically significant differences in the odds ratios for birth outcomes among the exposed and unexposed pregnancies.Conclusions/Significance
We found no statistically significant evidence of a harmful effect of gestational exposure to the rBS-WC vaccine. These findings, along with the absence of a rational basis for expecting a risk from this killed oral bacterial vaccine, are reassuring but the study had insufficient power to detect infrequent events.Trial Registration
ClinicalTrials.gov NCT00709410相似文献24.
Kimberley B. Ritter David R. Jordan Scott C. Chapman Ian D. Godwin Emma S. Mace C. Lynne McIntyre 《Molecular breeding : new strategies in plant improvement》2008,22(3):367-384
QTL for stem sugar-related and other agronomic traits were identified in a converted sweet (R9188) × grain (R9403463-2-1)
sorghum population. QTL analyses were conducted using phenotypic data for 11 traits measured in two field experiments and
a genetic map comprising 228 SSR and AFLP markers grouped into 16 linkage groups, of which 11 could be assigned to the 10
sorghum chromosomes (SBI-01 to SBI-10). QTL were identified for all traits and were generally co-located to five locations
(SBI-01, SBI-03, SBI-05, SBI-06 and SBI-10). QTL alleles from R9188 were detected for increased sucrose content and sugar
content on SBI-01, SBI-05 and SBI-06. R9188 also contributed QTL alleles for increased Brix on SBI-05 and SBI-06, and increased
sugar content on SBI-03. QTL alleles from R9403463-2-1 were found for increased sucrose content and sucrose yield on SBI-10,
and increased glucose content on SBI-07. QTL alleles for increased height, later flowering and greater total dry matter yield
were located on SBI-01 of R9403463-2-1, and SBI-06 of R9188. QTL alleles for increased grain yield from both R9403463-2-1
and R9188 were found on SBI-03. As an increase in stem sugars is an important objective in sweet sorghum breeding, the QTL
identified in this study could be further investigated for use in marker-assisted selection of sweet sorghum. 相似文献
25.
A. G. Connolly I. D. Godwin M. Cooper I. H. DeLacy 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(3-4):332-336
In this paper we present a method for the generation of randomly amplified polymorphic DNA (RAPD) markers for sweet potato. These were applied to produce genetic fingerprints of six clonal cultivars and to estimate genetic distances between these cultivars. The level of polymorphism within the species was extremely high. From the 36-decamer random primers used, 170 fragments were amplified, of which 132 (77.6%) were polymorphic. Ten primers resulted in no detected amplification. Of the remaining 26 primers for which amplification was achieved, only one did not reveal polymorphism. Six primers used alone enabled the discrimination of all six genotypes. Pattern analysis, which employed both a classification and ordination method, enabled the grouping of cultivars and the identification of primers which gave greatest discrimination among the cultivars. 相似文献
26.
Chukwujindu M. A. Iwegbue Ufuoma A. Onyonyewoma Francisca I. Bassey Godwin E. Nwajei Bice S. Martincigh 《人类与生态风险评估》2015,21(2):338-357
Concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) were determined in 40 brands of biscuits in the Nigerian market. The analyses were performed by gas chromatography-flame ionisation detection (GC-FID) after Soxhlet extraction of the sample with hexane/dichloromethane and clean-up of the extract. The concentrations of Σ16 PAHs in these biscuit samples were in the range of 35.7–645.3 μg kg?1, 75.9–490.7 μg kg?1, 91.5–537 μg kg?1, 18.4–522.2 μg kg?1, 123.5–393.8 μg kg?1, 167.2–880 μg kg?1, 136.5–316 μg kg?1, and 135.5–241.6 μg kg?1 for shortcake, digestives, cookies, shortbread, wafers, crackers, Pringles, and cabin, respectively. The concentrations of Σ8 carcinogenic PAHs in the samples ranged from not detected (nd)–323.3 μg kg?1, 15.7–138 μg kg?1, 9.7–312.9 μg kg?1, nd–331.7 μg kg?1, nd–220.9 μg kg?1, nd–53.3 μg kg?1, 18.4–56.6 μg kg?1, and 6.6–170.8 μg kg?1 for shortcake, digestives, cookies, shortbread, wafers, crackers, Pringles, and cabin, respectively. The margin of exposure (MOE), based on PAH8 as an indicator for the occurrence and effects of PAHs in food, was less than 10,000, the serious health effects value, in 30% and 8% of the brands for the child and adult scenarios, respectively. 相似文献
27.
Kathrin S. Grassme Acely Garza-Garcia Jean-Paul Delgado James W. Godwin Anoop Kumar Phillip B. Gates Paul C. Driscoll Jeremy P. Brockes 《PloS one》2016,11(4)
Anterior gradient (AG) proteins have a thioredoxin fold and are targeted to the secretory pathway where they may act in the ER, as well as after secretion into the extracellular space. A newt member of the family (nAG) was previously identified as interacting with the GPI-anchored salamander-specific three-finger protein called Prod1. Expression of nAG has been implicated in the nerve dependence of limb regeneration in salamanders, and nAG acted as a growth factor for cultured newt limb blastemal (progenitor) cells, but the mechanism of action was not understood. Here we show that addition of a peptide antibody to Prod1 specifically inhibit the proliferation of blastema cells, suggesting that Prod1 acts as a cell surface receptor for secreted nAG, leading to S phase entry. Mutation of the single cysteine residue in the canonical active site of nAG to alanine or serine leads to protein degradation, but addition of residues at the C terminus stabilises the secreted protein. The mutation of the cysteine residue led to no detectable activity on S phase entry in cultured newt limb blastemal cells. In addition, our phylogenetic analyses have identified a new Caudata AG protein called AG4. A comparison of the AG proteins in a cell culture assay indicates that nAG secretion is significantly higher than AGR2 or AG4, suggesting that this property may vary in different members of the family. 相似文献
28.
Maya L. Groner Luke A. Rogers Andrew W. Bateman Brendan M. Connors L. Neil Frazer Sean C. Godwin Martin Krko?ek Mark A. Lewis Stephanie J. Peacock Erin E. Rees Crawford W. Revie Ulrike E. Schl?gel 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1689)
Effective disease management can benefit from mathematical models that identify drivers of epidemiological change and guide decision-making. This is well illustrated in the host–parasite system of sea lice and salmon, which has been modelled extensively due to the economic costs associated with sea louse infections on salmon farms and the conservation concerns associated with sea louse infections on wild salmon. Consequently, a rich modelling literature devoted to sea louse and salmon epidemiology has been developed. We provide a synthesis of the mathematical and statistical models that have been used to study the epidemiology of sea lice and salmon. These studies span both conceptual and tactical models to quantify the effects of infections on host populations and communities, describe and predict patterns of transmission and dispersal, and guide evidence-based management of wild and farmed salmon. As aquaculture production continues to increase, advances made in modelling sea louse and salmon epidemiology should inform the sustainable management of marine resources. 相似文献
29.
Emmanuel A. Oga Lisa M. Schumaker Biodun Sulyman Alabi Darlington Obaseki Aniefon Umana Ima-Abasi Bassey Godwin Ebughe Olabode Oluwole Teniola Akeredolu Sally N. Adebamowo Patrick Dakum Kevin Cullen Clement A. Adebamowo 《PloS one》2016,11(4)
IntroductionThe burden of HPV-related Head and Neck Cancers (HNC) has been rising in the U.S. and other developed countries but this trend has not been reported in Africa. Objective of study was to evaluate the prevalence of HPV infection in HNC cancer cases seen between 1990 and 2011 at the tertiary health care institutions in Nigeria.MethodsWe retrieved 149 head and neck cancer formalin fixed, paraffin embedded tumor specimens diagnosed between 1990 and 2011 from four teaching hospitals in Nigeria. One hundred and twenty-three blocks (83%) contained appropriate HNC for analysis while DNA extraction was successful in 60% (90/149). PCR amplification was successful in 33% (49/149) and Linear Array genotyping for HPV was successful in 11% (17/149) of these cases. These were in tumors from the larynx (6), cervical lymph nodes (3), nasal cavity (2), parotid (1), palate (1), maxillary sinus (1) and mandible (1). Two cases were non-specific and none were from the oropharynx. Histologically, 41% (7/17) of the successfully genotyped blocks were squamous cell carcinomas (larynx 6, maxillary sinus 1).