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261.
Cheryl Cohen Jocelyn Moyes Stefano Tempia Michelle Groome Sibongile Walaza Marthi Pretorius Halima Dawood Meera Chhagan Summaya Haffejee Ebrahim Variava Kathleen Kahn Anne von Gottberg Nicole Wolter Adam L. Cohen Babatyi Malope-Kgokong Marietjie Venter Shabir A. Madhi 《PloS one》2015,10(3)
Introduction
Data on the burden and risk groups for influenza-associated mortality from Africa are limited. We aimed to estimate the incidence and risk-factors for in-hospital influenza-associated severe acute respiratory illness (SARI) deaths.Methods
Hospitalised patients with SARI were enrolled prospectively in four provinces of South Africa from 2009–2013. Using polymerase chain reaction, respiratory samples were tested for ten respiratory viruses and blood for pneumococcal DNA. The incidence of influenza-associated SARI deaths was estimated at one urban hospital with a defined catchment population.Results
We enrolled 1376 patients with influenza-associated SARI and 3% (41 of 1358 with available outcome data) died. In patients with available HIV-status, the case-fatality proportion (CFP) was higher in HIV-infected (5%, 22/419) than HIV-uninfected individuals (2%, 13/620; p = 0.006). CFPs varied by age group, and generally increased with increasing age amongst individuals >5 years (p<0.001). On multivariable analysis, factors associated with death were age-group 45–64 years (odds ratio (OR) 4.0, 95% confidence interval (CI) 1.01–16.3) and ≥65 years (OR 6.5, 95%CI 1.2–34.3) compared to 1–4 year age-group who had the lowest CFP, HIV-infection (OR 2.9, 95%CI 1.1–7.8), underlying medical conditions other than HIV (OR 2.9, 95%CI 1.2–7.3) and pneumococcal co-infection (OR 4.1, 95%CI 1.5–11.2). The estimated incidence of influenza-associated SARI deaths per 100,000 population was highest in children <1 year (20.1, 95%CI 12.1–31.3) and adults aged 45–64 years (10.4, 95%CI 8.4–12.9). Adjusting for age, the rate of death was 20-fold (95%CI 15.0–27.8) higher in HIV-infected individuals than HIV-uninfected individuals.Conclusion
Influenza causes substantial mortality in urban South Africa, particularly in infants aged <1 year and HIV-infected individuals. More widespread access to antiretroviral treatment and influenza vaccination may reduce this burden. 相似文献262.
Cheryl Cohen Sibongile Walaza Jocelyn Moyes Michelle Groome Stefano Tempia Marthi Pretorius Orienka Hellferscee Halima Dawood Summaya Haffejee Ebrahim Variava Kathleen Kahn Akhona Tshangela Anne von Gottberg Nicole Wolter Adam L. Cohen Babatyi Kgokong Marietjie Venter Shabir A. Madhi 《PloS one》2015,10(2)
ObjectiveThere are few published studies describing severe acute respiratory illness (SARI) epidemiology amongst older children and adults from high HIV-prevalence settings. We aimed to describe SARI epidemiology amongst individuals aged ≥5 years in South Africa.MethodsWe conducted prospective surveillance for individuals with SARI from 2009–2012. Using polymerase chain reaction, respiratory samples were tested for ten viruses, and blood for pneumococcal DNA. Cumulative annual SARI incidence was estimated at one site with population denominators.FindingsWe enrolled 7193 individuals, 9% (621/7067) tested positive for influenza and 9% (600/6519) for pneumococcus. HIV-prevalence was 74% (4663/6334). Among HIV-infected individuals with available data, 41% of 2629 were receiving antiretroviral therapy (ART). The annual SARI hospitalisation incidence ranged from 325-617/100,000 population. HIV-infected individuals experienced a 13–19 times greater SARI incidence than HIV-uninfected individuals (p<0.001). On multivariable analysis, compared to HIV-uninfected individuals, HIV-infected individuals were more likely to be receiving tuberculosis treatment (odds ratio (OR):1.7; 95%CI:1.1–2.7), have pneumococcal infection (OR 2.4; 95%CI:1.7–3.3) be hospitalised for >7 days rather than <2 days (OR1.7; 95%CI:1.2–2.2) and had a higher case-fatality ratio (8% vs 5%;OR1.7; 95%CI:1.2–2.3), but were less likely to be infected with influenza (OR 0.6; 95%CI:0.5–0.8). On multivariable analysis, independent risk indicators associated with death included HIV infection (OR 1.8;95%CI:1.3–2.4), increasing age-group, receiving mechanical ventilation (OR 6.5; 95%CI:1.3–32.0) and supplemental-oxygen therapy (OR 2.6; 95%CI:2.1–3.2).ConclusionThe burden of hospitalized SARI amongst individuals aged ≥5 years is high in South Africa. HIV-infected individuals are the most important risk group for SARI hospitalization and mortality in this setting. 相似文献
263.
Coal-derived sodium humate was found to stimulate primary root growth of seedlings of cantaloupe (Cucumis melo L.) at 1000 mg L–1, lettuce (Lactuca sativa L.) and onion (Allium cepa L.) at 500 and 1000 mg L–1, as well as hypocotyl growth of cantaloupe at 1000 mg L–1. Growth enhancement was not due to release of nutrient elements by the product, and, in the case of lettuce and onion, was not due to increased availability or uptake of mineral elements. Growth stimulation of cantaloupe, however, was dependent on the provision of nutrient solution. Growth stimulation of onion roots under axenic conditions indicated an effect of the humate per se rather than a response mediated via microbial breakdown products. 相似文献
264.
Cloning, sequence analysis and chromosome localization of a Drosophila muscarinic acetylcholine receptor 总被引:2,自引:0,他引:2
T Onai M G FitzGerald S Arakawa J D Gocayne D A Urquhart L M Hall C M Fraser W R McCombie J C Venter 《FEBS letters》1989,255(2):219-225
Two cDNA clones (3.7 kb and 4.8 kb) encoding a Drosophila muscarinic acetylcholine receptor were isolated from a Drosophila head cDNA library and characterized by automated DNA sequence analysis. The Drosophila muscarinic receptor contains 788 amino acids with a calculated Mr of 84,807 and displays greater than 60% homology with mammalian muscarinic receptors. The muscarinic receptor maps to the tip of the right arm of the second chromosome of the Drosophila genome. 相似文献
265.
E. Venter A.-M. Botha 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(6):965-970
Through random amplified polymorphic DNA (RAPD) analysis we identified a putative marker linked to the Dn5 resistance gene. This marker was converted to a more reliable sequence-characterised-amplified regions (SCAR) marker. The
initial SCAR marker amplified the correct amplification product but failed to discern between the susceptible and resistant
individuals. Hence, it was utilised to sequence the internal fragment. All nested primers designed from the internal sequences
were also unable to produce any polymorphism between the susceptible and resistant cultivars. Restriction digests were then
performed on these fragments, and the restriction enzyme EcoRI was able to discern between the susceptible and resistant F2 individuals of the Dn5 population. This granted one marker amplified with the internal SCAR primer set OPF141083 the ability to differentiate between parental individuals carrying the Dn5 genes. This marker was tested in a segregating F2 population carrying the Dn5 resistance gene and proved able to differentiate between the segregating individuals. This marker may prove useful in marker
assisted selection (MAS), although performing restriction digests may hamper the throughput of a high number of samples.
Received: 4 August 1999 / Accepted: 27 August 1999 相似文献
266.
A sulfhydryl group of the canine cardiac beta-adrenergic receptor observed in the absence of hormone
Canine cardiac beta-adrenergic receptors contain a free sulfhydryl group in the adrenergic ligand binding site. [125 I]-Iodohydroxybenzylpindolol [( 125 I]-IHYP) binding to cardiac beta-receptors was inhibited 80% by treatment with 1 mM p-chloromercuribenzoic acid (pCMB). Occupation of the beta-receptors by an antagonist prior to treatment with pCMB prevented this effect suggesting that a sulfhydryl group is present in or near the ligand binding site of the cardiac beta-receptor. In the presence of agonists, the sensitivity of cardiac beta-receptors to pCMB was increased. Incubation of isoproterenol-occupied cardiac beta-receptors, resulted in a 57% inhibition of [125 I]-IHYP binding measured after extensive washing to remove bound agonist. The ability of isoproterenol to increase the reactivity of cardiac beta-adrenergic receptors supports the hypothesis that agonists produce a conformational change upon binding. 相似文献
267.
268.
We have characterized the structure of purified beta-adrenergic receptors by a combination of photoaffinity labeling, high performance liquid chromatography (HPLC)-tryptic mapping, CNBr fragmentation, target size analysis, and electron microscopy of purified receptor molecules. Guinea pig lung beta-adrenergic receptors purified by affinity chromatography, ion exchange chromatography, and HPLC size exclusion chromatography or photoaffinity labeled with [125]-iodocyanopindolol diazirine displayed mobilities on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) that corresponded to Mr = 68,000. Purified, radioiodinated guinea pig lung beta-receptors were subjected to complete trypsin digestion and subsequent reverse-phase HPLC analysis, which revealed nine peptides. Active site labeling and tryptic digestion of partially purified hamster lung beta-receptors produced one peptide, whereas CNBr digestion of the same material produced two labeled fragments, yielding information about the location of the active site within the primary sequence. Purified guinea pig lung receptors were examined with transmission electron microscopy. Electron micrographs revealed slightly asymmetric, rod-shaped structures with an average length of 13 nm and width of 3.4 nm. Many receptors were arranged as apparent dimeric structures. These findings confirm data obtained from target size analysis of guinea pig lung beta-receptors in situ which suggest that receptors may exist as oligomeric arrays in the native membrane. Taken together, these data provide information about putative functional domains of the beta-adrenergic receptor and its quaternary structure. 相似文献
269.
Use of the complete genome sequence information of Haemophilus influenzae strain Rd to investigate lipopolysaccharide biosynthesis 总被引:4,自引:3,他引:1
Derek W. Hood Mary E. Deadman Tina Allen Hussein Masoud Adele Martin Jean Robert Brisson Robert Fleischmann J. Craig Venter James C. Richards & E. Richard Moxon 《Molecular microbiology》1996,22(5):951-965
The availability of the complete 1.83-megabase-pair sequence of the Haemophilus influenzae strain Rd genome has facilitated significant progress in investigating the biology of H. influenzae lipopolysaccharide (LPS), a major virulence determinant of this human pathogen. By searching the H. influenzae genomic database, with sequences of known LPS biosynthetic genes from other organisms, we identified and then cloned 25 candidate LPS genes. Construction of mutant strains and characterization of the LPS by reactivity with monoclonal antibodies, PAGE fractionation patterns and electrospray mass spectrometry comparative analysis have confirmed a potential role in LPS biosynthesis for the majority of these candidate genes. Virulence studies in the infant rat have allowed us to estimate the minimal LPS structure required for intravascular dissemination. This study is one of the first to demonstrate the rapidity, economy and completeness with which novel biological information can be accessed once the complete genome sequence of an organism is available. 相似文献
270.
Localization of penicillin-binding proteins to the splitting system of Staphylococcus aureus septa by using a mercury-penicillin V derivative. 总被引:1,自引:0,他引:1 下载免费PDF全文
T R Paul A Venter L C Blaszczak T R Parr Jr H Labischinski T J Beveridge 《Journal of bacteriology》1995,177(13):3631-3640
Precise localization of penicillin-binding protein (PBP)-antibiotic complexes in a methicillin-sensitive Staphylococcus aureus strain (BB255), its isogenic heterogeneous methicillin-resistant transductant (BB270), and a homogeneous methicillin-resistant strain (Col) was investigated by high-resolution electron microscopy. A mercury-penicillin V (Hg-pen V) derivative was used as a heavy metal-labeled, electron-dense probe for accurately localizing PBPs in situ in single bacterial cells during growth. The most striking feature of thin sections was the presence of an abnormally large (17 to 24 nm in width) splitting system within the thick cross walls or septa of Hg-pen V-treated bacteria of all strains. Untreated control cells possessed a thin, condensed splitting system, 7 to 9 nm in width. A thick splitting system was also distinguishable in unstained thin sections, thereby confirming that the electron contrast of this structure was not attributed to binding of bulky heavy metal stains usually used for electron microscopy. Biochemical analyses demonstrated that Hg-pen V bound to isolated plasma membranes as well as sodium dodecyl sulfate-treated cell walls and that two or more PBPs in each strain bound to this antibiotic. In contrast, the splitting system in penicillin V-treated bacteria was rarely visible after 30 min in the presence of antibiotic. These findings suggest that while most PBPs were associated with the plasma membrane, a proportion of PBPs were located within the fabric of the cell wall, in particular, in the splitting system. Inhibition of one or more high-M(r) PBPs by beta-lactam antibiotics modified the splitting system and cross-wall structure, therefore supporting a role for these PBPs in the synthesis and architectural design of these structures in S. aureus. 相似文献