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Manish Mahawar Seham M. Rabadi Sukalyani Banik Sally V. Catlett Dennis W. Metzger Meenakshi Malik Chandra Shekhar Bakshi 《PloS one》2013,8(4)
Francisella tularensis is the causative agent of a fatal human disease, tularemia. F. tularensis was used in bioweapon programs in the past and is now classified as a category A select agent owing to its possible use in bioterror attacks. Despite over a century since its discovery, an effective vaccine is yet to be developed. In this study four transposon insertion mutants of F. tularensis live vaccine strain (LVS) in Na/H antiporter (FTL_0304), aromatic amino acid transporter (FTL_0291), outer membrane protein A (OmpA)-like family protein (FTL_0325) and a conserved hypothetical membrane protein gene (FTL_0057) were evaluated for their attenuation and protective efficacy against F. tularensis SchuS4 strain. All four mutants were 100–1000 fold attenuated for virulence in mice than parental F. tularensis. Except for the FTL_0304, single intranasal immunization with the other three mutants provided 100% protection in BALB/c mice against intranasal challenge with virulent F. tularensis SchuS4. Differences in the protective ability of the FTL_0325 and FTL_0304 mutant which failed to provide protection against SchuS4 were investigated further. The results indicated that an early pro-inflammatory response and persistence in host tissues established a protective immunity against F. tularensis SchuS4 in the FTL_0325 immunized mice. No differences were observed in the levels of serum IgG antibodies amongst the two vaccinated groups. Recall response studies demonstrated that splenocytes from the FTL_0325 mutant immunized mice induced significantly higher levels of IFN-γ and IL-17 cytokines than the FTL_0304 immunized counterparts indicating development of an effective memory response. Collectively, this study demonstrates that persistence of the vaccine strain together with its ability to induce an early pro-inflammatory innate immune response and strong memory responses can discriminate between successful and failed vaccinations against tularemia. This study describes a live attenuated vaccine which may prove to be an ideal vaccine candidate for prevention of respiratory tularemia. 相似文献
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Lakhvir Kaur Kanwaldeep Singh Surinder Paul Sukhprit Singh Shashank Singh Subheet Kumar Jain 《AAPS PharmSciTech》2018,19(4):1606-1624
Type of biological membrane used in skin permeation experiment significantly affects skin permeation and deposition potential of tested formulations. In this study, a comparative study has been carried out to evaluate the potential of a synthetic membrane (Strat-M?) with rat, human, and porcine ear skin to carry out skin permeation study of nanoformulations of a high molecular weight drug, amphotericin B. Results demonstrated that the permeation of this high molecular weight drug through Strat-M? showed close similitude to human skin. Value of correlation coefficient (R2) of log diffusion between Strat-M? and human skin was found to be 0.99 which demonstrated the similarities of Strat-M? membrane to the human skin. In similarity factor analysis, the value of f2 was also found to be 85, which further demonstrated the similarities of Strat-M? membrane to human skin. Moreover, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis of synthetic and biological membranes depicted almost similar morphological features (thickness, pore size, surface morphology, and diameter) of synthetic membrane with human skin. The results of the study demonstrated Strat-M? as a better alternative to carry out skin permeation experiment due to the consistent results, reproducibility, easy availability, and minimum variability with human skin. 相似文献
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Helen Louise May-Simera Qin Wan Balendu Shekhar Jha Juliet Hartford Vladimir Khristov Roba Dejene Justin Chang Sarita Patnaik Quanlong Lu Poulomi Banerjee Jason Silver Christine Insinna-Kettenhofen Dishita Patel Mostafa Lotfi May Malicdan Nathan Hotaling Arvydas Maminishkis Rupa Sridharan Kapil Bharti 《Cell reports》2018,22(1):189-205
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A Method for Selection and Characterization of Rhizosphere-Competent Bacteria of Chickpea 总被引:1,自引:0,他引:1
Chandra Shekhar Nautiyal 《Current microbiology》1997,34(1):12-17
A greenhouse assay was developed to evaluate the root-colonizing capability of the native chickpea rhizospheric bacterial
population. In this assay system, screening time was reduced on two counts. First, spontaneous chromosomal rifampicin-resistant
(Rifr) strains were directly inoculated to seeds without any check for the stability of the mutation, and second, no attempts were
made to taxonomically identify all the strains being screened for chickpea rhizosphere competence. Only two chickpea rhizosphere-competent
Rifr strains from the group of six good chickpea rhizosphere colonizers forming 107 to 108 colony-forming units (cfu)/g root were taxonomically identified as Pseudomonas fluorescens NB13R and Pseudomonas spp. NB49R, after screening 49 bacteria. Both the strains showed no difference from their corresponding wild-type strains
P. fluorescens NB13 and Pseudomonas spp. NB49 in terms of chickpea rhizosphere competence. Isogenic or equally rhizospheric competitive second non-isogenic bacterial
isolate, when present in tenfold higher amount, pre-empted the colonization of the soil by the bacterium, which was present
in smaller ratio. These findings indicate that the isogenic or equally rhizospheric competitive second non-isogenic Rifr strains should be compared for their survival and competition with that of the isogenic parent and with each other for specific
ecological niche, before using a mixture of isolates, for stable and consistent biological seed treatment to control soilborn
pathogens or pests or to promote plant growth.
Received: 31 May 1996 / Accepted: 5 July 1996 相似文献
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Suzuki Go Keshavmurthy Shashank Hayashibara Takeshi Wallace Carden C. Shirayama Yoshihisa Chen Chaolun Allen Fukami Hironobu 《Coral reefs (Online)》2016,35(4):1419-1432
Coral Reefs - Zooxanthellate corals are found throughout the tropics, but also extend into subtropical and marginal locations due to the presence of warm ocean currents. The population history of... 相似文献
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