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31.
32.
Vincent Kayina Samuel Kyobe Fred A. Katabazi Edgar Kigozi Moses Okee Beatrice Odongkara Harriet M. Babikako Christopher C. Whalen Moses L. Joloba Philippa M. Musoke Ezekiel Mupere 《PloS one》2015,10(4)
Background
We determined prevalence of pertussis infection and its associated host and environmental factors to generate information that would guide strategies for disease control.Methods
In a cross-sectional study, 449 children aged 3 months to 12 years with persistent cough lasting ≥14 days were enrolled and evaluated for pertussis using DNA polymerase chain reaction (PCR) and ELISA serology tests.Results
Pertussis prevalence was 67 (15% (95% Confidence Interval (CI): 12–18)) and 81 (20% (95% CI: 16–24)) by PCR and ELISA, respectively among 449 participating children. The prevalence was highest in children with >59 months of age despite high vaccination coverage of 94% in this age group. Study demographic and clinical characteristics were similar between pertussis and non-pertussis cases. Of the 449 children, 133 (30%) had a coughing household member and 316 (70%) did not. Among 133 children that had a coughing household member, sex of child, sharing bed with a coughing household member and having a coughing individual in the neighborhood were factors associated with pertussis. Children that had shared a bed with a coughing household individual had seven-fold likelihood of having pertussis compared to children that did not (odds ratio (OR) 7.16 (95% CI: 1.24–41.44)). Among the 316 children that did not have a coughing household member, age <23 months, having or contact with a coughing individual in neighborhood, a residence with one room, and having a caretaker with >40 years of age were the factors associated with pertussis. Age <23months was three times more likely to be associated with pertussis compared to age 24–59 months (OR 2.97 (95% CI: 1.07–8.28)).Conclusion
Findings suggest high prevalence of pertussis among children with persistent cough at a health facility and it was marked in children >59 months of age, suggesting the possibility of waning immunity. The factors associated with pertussis varied by presence or absence of a coughing household member. 相似文献33.
Sabah O. Odman-Ghazi Abraham Abraha Erica Taylor Isom Margaret M. Whalen 《Cell biology and toxicology》2010,26(5):469-479
Previous studies have shown that dibutyltin (DBT) interferes with the function of human natural killer (NK) cells, diminishing
their capacity to destroy tumor cells, in vitro. DBT is a widespread environmental contaminant and has been found in human
blood. As NK cells are our primary immune defense against tumor cells, it is important to understand the mechanism by which
DBT interferes with their function. The current study examines the effects of DBT exposures on key enzymes in the signaling
pathway that regulates NK responsiveness to tumor cells. These include several protein tyrosine kinases (PTKs), mitogen-activated
protein kinases (MAPKs), and mitogen-activated protein kinase kinases (MAP2Ks). The results showed that in vitro exposures
of NK cells to DBT had no effect on PTKs. However, exposures to DBT for as little as 10 min were able to increase the phosphorylation
(activation) of the MAPKs. The DBT-induced activations of these MAPKs appear to be due to DBT-induced activations of the immediate
upstream activators of the MAPKs, MAP2Ks. The results suggest that DBT-interference with the MAPK signaling pathway is a consequence
of DBT exposures, which could account for DBT-induced decreases in NK function. 相似文献
34.
Andréia S Lessa Bruno D Paredes Juliana V Dias Adriana B Carvalho Luiz Fernando Quintanilha Christina M Takiya Bernardo R Tura Guilherme FM Rezende Antonio C Campos de Carvalho Célia MC Resende Regina CS Goldenberg 《BMC veterinary research》2010,6(1):1-10
Background
Atypical scrapie was first identified in Norwegian sheep in 1998 and has subsequently been identified in many countries. Retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease. However, atypical scrapie isolates have been shown to be infectious experimentally, through intracerebral inoculation in transgenic mice and sheep. The first successful challenge of a sheep with 'field' atypical scrapie from an homologous donor sheep was reported in 2007.Results
This study demonstrates that atypical scrapie has distinct clinical, pathological and biochemical characteristics which are maintained on transmission and sub-passage, and which are distinct from other strains of transmissible spongiform encephalopathies in the same host genotype.Conclusions
Atypical scrapie is consistently transmissible within AHQ homozygous sheep, and the disease phenotype is preserved on sub-passage. 相似文献35.
Measuring nitrogen (N) transformations from organic fertilizers can help in selecting applications rates that provide sufficient soluble N to promote tree growth in short-rotation plantations. The objective of this study was to determine how organic fertilizers (papermill biosolids, liquid pig slurry) affected microbially-mediated N transformations in soils. Soil samples were collected from a hybrid poplar plantation before fertilization, 1 month after fertilizer application and at the end of the growing season. Net N mineralization and nitrification were evaluated during a 28 d laboratory incubation, while gross N transformations were assessed using a 15N isotope dilution technique. Pig slurry application increased soil ammonium (NH4-N) and nitrate (NO3-N) concentrations within 1 month, while papermill biosolids increased soil NH4-N and NO3-N concentrations at the end of the growing season. Gross N consumption rates were greater than gross N production rates. The NH4-N and NO3-N consumption rates were positively correlated with labile carbon and microbial biomass. The gross nitrification rate was 18 to 67% of the gross mineralization rate but 30% or less of the gross NH4-N consumption rate, indicating that NH4 consumption was overestimated by the isotope dilution technique. We conclude that N cycling in this hybrid poplar plantation was characterized by rapid consumption of plant-available N following N mineralization and nitrification. 相似文献
36.
van Beers JJ Raijmakers R Alexander LE Stammen-Vogelzangs J Lokate AM Heck AJ Schasfoort RB Pruijn GJ 《Arthritis research & therapy》2010,12(6):R219
Introduction
Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology. 相似文献37.
38.
Stein CM Zalwango S Chiunda AB Millard C Leontiev DV Horvath AL Cartier KC Chervenak K Boom WH Elston RC Mugerwa RD Whalen CC Iyengar SK 《Human genetics》2007,121(6):663-673
Tuberculosis (TB) is a growing public health threat globally and several studies suggest a role of host genetic susceptibility
in increased TB risk. As part of a household contact study in Kampala, Uganda, we have taken a unique approach to the study
of genetic susceptibility to TB by developing an intermediate phenotype model for TB susceptibility, analyzing levels of tumor
necrosis factor-α (TNFα) in response to culture filtrate as the phenotype. In the present study, we analyzed candidate genes
related to TNFα regulation and found that interleukin (IL)-10, interferon-gamma receptor 1 (IFNGR1), and TNFα receptor 1 (TNFR1) genes were linked and associated to both TB and TNFα. We also show that these associations are with progression to active
disease and not susceptibility to latent infection. This is the first report of an association between TB and TNFR1 in a human population and our findings for IL-10 and IFNGR1 replicate previous findings. By observing pleiotropic effects on both phenotypes, we show construct validity of our intermediate
phenotype model, which enables the characterization of the role of these genetic polymorphisms on TB pathogenesis. This study
further illustrates the utility of such a model for disentangling complex traits.
C. C. Whalen and S. K. Iyengar contributed equally as senior authors of this work. 相似文献
39.
Sidders B Withers M Kendall SL Bacon J Waddell SJ Hinds J Golby P Movahedzadeh F Cox RA Frita R Ten Bokum AM Wernisch L Stoker NG 《Genome biology》2007,8(12):R265-13
We describe an analysis, applicable to any spotted microarray dataset produced using genomic DNA as a reference, that quantifies prokaryotic levels of mRNA on a genome-wide scale. Applying this to Mycobacterium tuberculosis, we validate the technique, show a correlation between level of expression and biological importance, define the complement of invariant genes and analyze absolute levels of expression by functional class to develop ways of understanding an organism's biology without comparison to another growth condition. 相似文献
40.
José MC Ribeiro Bruno Arcà Fabrizio Lombardo Eric Calvo My Van Phan Prafulla K Chandra Stephen K Wikel 《BMC genomics》2007,8(1):1-27