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71.
Enhanced resistance to citrus canker in transgenic mandarin expressing Xa21 from rice 总被引:1,自引:0,他引:1
Ahmad A. Omar Mayara M. Murata Hesham A. El-Shamy James H. Graham Jude W. Grosser 《Transgenic research》2018,27(2):179-191
Genetic engineering approaches offer an alternative method to the conventional breeding of Citrus sp. ‘W. Murcott’ mandarin (a hybrid of ‘Murcott’ and an unknown pollen parent) is one of the most commercially important cultivars grown in many regions around the world. Transformation of ‘W. Murcott’ mandarin was achieved by direct DNA uptake using a protoplast transformation system. DNA construct (pAO3), encoding Green Fluorescent Protein (GFP) and the cDNA of Xa21, a Xanthomonas resistance gene from rice, was used to transform protoplasts of ‘W. Murcott’ mandarin. Following citrus protoplast culture and regeneration, transformed micro calli were microscopically designated via GFP expression, physically isolated from non-transformed tissue, and cultured on somatic embryogenesis induction medium. More than 150 transgenic embryos were recovered and from them, ten transgenic lines were regenerated and cultured on rooting medium for shoot elongation. Transgenic shoots were micrografted and established in the greenhouse with 3–5 replicates per line. The insertion of Xa21 and GFP was confirmed by PCR and southern blot analysis. GFP expression was verified by fluorescence microscopy and western blot analysis revealed expression of Xa21 although it was variable among transgenic lines, as shown by RT-qPCR. Transgenic plants challenged with the citrus canker pathogen by syringe inoculation showed a reduction in lesion number and bacterial populations within lesions compared to non-transgenic control plants. Transgenic ‘W. Murcott’ mandarin lines with improved canker resistance via protoplast transformation from embryogenic callus with the Xa21 gene from rice are being evaluated under field conditions to validate the level of resistance. 相似文献
72.
Zainuddin Zainal Zahari Tarmizi Reza Chee Yap Keng Sarkawi Nur Nabila Ahmad Hafandi Salleh Annas Tahir Nur Diyana Mohamad Baiee Falah Che-Amat Azlan Fitri Wan-Nor 《Primates; journal of primatology》2022,63(4):377-386
Primates - Bornean orangutan is a critically endangered non-human primate; however, the threat of extinction is not merely from poaching and habitat loss. Orangutan survival is also threatened by... 相似文献
73.
Pourmoghadasiyan Bahareh Tavakkoli Fatemeh Beram Farzaneh Mahmoudi Badmasti Farzad Mirzaie Amir Kazempour Reza Rahimi Shahrzad Larijani Setare Farokhi Hejabi Faranak Sedaghatnia Kamand 《Molecular biology reports》2022,49(5):3597-3608
Molecular Biology Reports - In this study, the optimized niosomal formulation containing paclitaxel using non-ionic surfactants and cholesterol was designed and its cytotoxic effects against... 相似文献
74.
Masoud Mirmohammad sadeghi Amir Reza Modarresnia Farhad Shafiei 《Geomicrobiology journal》2013,30(5):453-465
The effects of experimental parameters including soil type, curing duration, inoculum size, and biomass and nutrients concentration on soil strengthening due to calcite precipitation by Sporosarcina pasteurii PTCC 1645 were investigated. The laboratory-scale mixing experiments on remolded samples were designed by the Taguchi method. Soil type proved to be the most incorporating factor, followed by curing time and nutrient concentration. The main effect and the interactions of the parameters were presented and the optimal conditions were obtained. This suggests the importance of local conditions including soil type on any future large-scale, in situ application. 相似文献
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76.
Henoch S. Hong Fareed Ahmad Johanna M. Eberhard Nupur Bhatnagar Benjamin A. Bollmann Phillip Keudel Matthias Ballmaier Margot Zielinska-Skowronek Reinhold E. Schmidt Dirk Meyer-Olson 《PloS one》2012,7(9)
NK cells are pivotal sentinels of the innate immune system and distinct subpopulations in peripheral blood have been described. A number of studies addressed HIV-induced alterations of NK cell phenotype and functionality mainly focusing on CD56dimCD16+ and CD56−CD16+ NK cells. However, the impact of HIV-infection on CD56bright NK cells is less well understood. Here we report a rise of CD56bright NK cells in HIV-infected individuals, which lack CCR7-expression and strongly correlate with HIV viral load. CCR7−CD56bright NK cells were characterized by increased cytolytic potential, higher activation states and a more differentiated phenotype. These cells thus acquired a number of features of CD56dimCD16+ NK cells. Furthermore, CD56bright NK cells from HIV patients exhibited higher degranulation levels compared to uninfected individuals. Thus, chronic HIV-infection is associated with a phenotypic and functional shift of CD56bright NK cells, which provides a novel aspect of HIV-associated pathogenesis within the NK cell compartment. 相似文献
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79.
Mohd Ishtikhar Tajjali Ilm Chandel Aamir Ahmad Mohd Sajid Ali Hamad A. Al-lohadan Ayman M. Atta Rizwan Hasan Khan 《PloS one》2015,10(9)
Quaternary amine of diethylaminoethyl rosin ester (QRMAE), chemically synthesized biocompatible rosin based cationic surfactant, has various biological applications including its use as a food product additive. In this study, we examined the amorphous aggregation behavior of mammalian serum albumins at pH 7.5, i.e., two units above their isoelectric points (pI ~5.5), and the roles played by positive charge and hydrophobicity of exogenously added rosin surfactant QRMAE. The study was carried out on five mammalian serum albumins, using various spectroscopic methods, dye binding assay, circular dichroism and electron microscopy. The thermodynamics of the binding of mammalian serum albumins to cationic rosin modified surfactant were established using isothermal titration calorimetry (ITC). It was observed that a suitable molar ratio of protein to QRMAE surfactant enthusiastically induces amorphous aggregate formation at a pH above two units of pI. Rosin surfactant QRMAE-albumins interactions revealed a unique interplay between the initial electrostatic and the subsequent hydrophobic interactions that play an important role towards the formation of hydrophobic interactions-driven amorphous aggregate. Amorphous aggregation of proteins is associated with varying diseases, from the formation of protein wine haze to the expansion of the eye lenses in cataract, during the expression and purification of recombinant proteins. This study can be used for the design of novel biomolecules or drugs with the ability to neutralize factor(s) responsible for the aggregate formation, in addition to various other industrial applications. 相似文献
80.
Martina Bakele Melanie Joos Sofia Burdi Nicolas Allgaier Simone P?schel Birgit Fehrenbacher Martin Schaller Veronica Marcos Jasmin Kümmerle-Deschner Nikolaus Rieber Niels Borregaard Amir Yazdi Andreas Hector Dominik Hartl 《The Journal of biological chemistry》2014,289(8):5320-5329
Neutrophils represent the major fraction of circulating immune cells and are rapidly recruited to sites of infection and inflammation. The inflammasome is a multiprotein complex that regulates the generation of IL-1 family proteins. The precise subcellular localization and functionality of the inflammasome in human neutrophils are poorly defined. Here we demonstrate that highly purified human neutrophils express key components of the NOD-like receptor family, pyrin domain containing 3 (NLRP3), and absent in melanoma 2 (AIM2) inflammasomes, particularly apoptosis-associated speck-like protein containing a CARD (ASC), AIM2, and caspase-1. Subcellular fractionation and microscopic analyses further showed that inflammasome components were localized in the cytoplasm and also noncanonically in secretory vesicle and tertiary granule compartments. Whereas IL-1β and IL-18 were expressed at the mRNA level and released as protein, highly purified neutrophils neither expressed nor released IL-1α at baseline or upon stimulation. Upon inflammasome activation, highly purified neutrophils released substantially lower levels of IL-1β protein compared with partially purified neutrophils. Serine proteases and caspases were differentially involved in IL-1β release, depending on the stimulus. Spontaneous activation of the NLRP3 inflammasome in neutrophils in vivo affected IL-1β, but not IL-18 release. In summary, these studies show that human neutrophils express key components of the inflammasome machinery in distinct intracellular compartments and release IL-1β and IL-18, but not IL-1α or IL-33 protein. Targeting the neutrophil inflammasome may represent a future therapeutic strategy to modulate neutrophilic inflammatory diseases, such as cystic fibrosis, rheumatoid arthritis, or sepsis. 相似文献