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991.
Sonia Aroui Souhir Brahim Abderraouf Kenani 《Biochemical and biophysical research communications》2010,391(1):419-226
One of the major obstacles which are opposed to the success of anticancer treatment is the cell resistance that generally develops after administration of commonly used drugs. In this study, we try to overcome the tumour cell resistance of doxorubicin (Dox) by developing a cell-penetrating peptide (CPP)-anticancer drug conjugate in aim to enhance its intracellular delivery and that its therapeutic effects. For this purpose, two cell-penetrating peptides, penetratin (pene) and tat, derived from the HIV-1 TAT protein, were chemically conjugated to Dox. The cytotoxicity, intracellular distribution and uptake were accessed in CHO cells (Chinese Hamster Ovarian carcinoma cells), HUVEC (Human Umbilical Vein Endothelial Cells), differentiated NG108.15 neuronal cell and breast cancer cells MCF7drug-sensitive or MDA-MB 231 drug-resistant cell lines. The conjugates showed different cell killing activity and intracellular distribution pattern by comparison to Dox as assessed respectively by MTT-based colorimetric cellular cytotoxicity assay, confocal fluorescence microscopy and FACS analysis. After treatment with 3 μM with Dox-CPPs for 2 h, pene increase the Dox cytotoxicity by 7.19-fold in CHO cells, by 11.53-fold in HUVEC cells and by 4.87-fold in MDA-MB 231 cells. However, cytotoxicity was decreased in NG108.15 cells and MCF7. Our CPPs-Dox conjugate proves the validity of CPPs for the cytoplasmic delivery of therapeutically useful molecules and also a valuable strategy to overcome drug resistance. 相似文献
992.
Tie Zheng Hou Jonathan P. Sherlock Sonia M. Parnell Derek W. Gilroy 《FEBS letters》2010,584(18):3955-3961
Macrophages are important tissue resident cells that regulate the dynamics of inflammation. However, they are strikingly heterogeneous. During studies looking at podoplanin (gp38) expression on stromal cells in the murine spleen and peritoneal cavity we unexpectedly discovered that podoplanin was expressed on a subset of F4/80+ macrophages; a subset which we have termed fibroblastic macrophages (FM). These cells function as phagocytes in vitro as measured by bead mediated phagocytosis assays. FM also exist at high frequency in the peritoneal cavity and in zymosan induced peritonitis in vivo. These FM represent a unique subgroup of F4/80+ macrophages and their presence in the inflamed peritoneum suggests that they play a role in zymosan induced peritonitis. 相似文献
993.
994.
Hydraulic lift through transpiration suppression in shrubs from two arid ecosystems: patterns and control mechanisms 总被引:2,自引:0,他引:2
Iván Prieto Karina Martínez-Tillería Luis Martínez-Manchego Sonia Montecinos Francisco I. Pugnaire Francisco A. Squeo 《Oecologia》2010,163(4):855-865
Hydraulic lift (HL) is the passive movement of water through the roots from deep wet to dry shallow soil layers when stomata
are closed. HL has been shown in different ecosystems and species, and it depends on plant physiology and soil properties.
In this study we explored HL patterns in several arid land shrubs, and developed a simple model to simulate the temporal evolution
and magnitude of HL during a soil drying cycle under relatively stable climatic conditions. This model was then used to evaluate
the influence of soil texture on the quantity of water lifted by shrubs in different soil types. We conducted transpiration
suppression experiments during spring 2005 in Chile and spring 2008 in Spain on five shrub species that performed HL, Flourensia thurifera, Senna cumingii and Pleocarphus revolutus (Chile), Retama sphaerocarpa and Artemisia barrelieri (Spain). Shrubs were covered with a black, opaque plastic fabric for a period of 48–72 h, and soil water potential was recorded
at different depths under the shrubs. While the shrubs remained covered, water potential continuously increased in shallow
soil layers until the cover was removed. The model output indicated that the amount of water lifted by shrubs is heavily dependent
on soil texture, as shrubs growing in loamy soils redistributed up to 3.6 times more water than shrubs growing on sandy soils.
This could be an important consideration for species growing in soils with different textures, as their ability to perform
HL would be context dependent. 相似文献
995.
996.
Christa Maes Steven Goossens Sonia Bartunkova Benjamin Drogat Lieve Coenegrachts Ingrid Stockmans Karen Moermans Omar Nyabi Katharina Haigh Michael Naessens Lieven Haenebalcke Jan P Tuckermann Marc Tjwa Peter Carmeliet Vice Mandic Jean-Pierre David Axel Behrens Andras Nagy Geert Carmeliet Jody J Haigh 《The EMBO journal》2010,29(2):424-441
997.
Massimo Gianotti Corrado Corti Sonia Delle Fratte Romano Di Fabio Colin P. Leslie Francesca Pavone Laura Piccoli Luigi Stasi Mark J. Wigglesworth 《Bioorganic & medicinal chemistry letters》2010,20(17):5069-5073
A novel imidazobenzazepine template (5a) with potent dual H1/5-HT2A antagonist activity was identified. Application of a zwitterionic approach to this poorly selective and poorly developable starting point successfully delivered a class of high quality leads, 3-[4-(3-R1-2-R-5H-imidazo[1,2-b][2]benzazepin-11-yl)-1-piperazinyl]-2,2-dimethylpropanoic acids (e.g., 9, 19, 20, and 21), characterized by potent and balanced H1/5-HT2A receptor antagonist activities and good developability profiles. 相似文献
998.
Elise Isabel Kevin P. Bateman Nathalie Chauret Wanda Cromlish Sylvie Desmarais Le T. Duong Jean-Pierre Falgueyret Jacques Yves Gauthier Sonia Lamontagne Cheuk K. Lau Serge Léger Tammy LeRiche Jean-François Lévesque Chun Sing Li Frédéric Massé Daniel J. McKay Christophe Mellon Deborah A. Nicoll-Griffith Renata M. Oballa M. David Percival W. Cameron Black 《Bioorganic & medicinal chemistry letters》2010,20(3):887-892
MK-0674 is a potent and selective cathepsin K inhibitor from the same structural class as odanacatib with a comparable inhibitory potency profile against Cat K. It is orally bioavailable and exhibits long half-life in pre-clinical species. In vivo studies using deuterated MK-0674 show stereoselective epimerization of the alcohol stereocenter via an oxidation/reduction cycle. From in vitro incubations, two metabolites could be identified: the hydroxyleucine and the glucuronide conjugate which were confirmed using authentic synthetic standards. 相似文献
999.
Sonia Gómez-Galera Eduard Rojas Duraialagaraja Sudhakar Changfu Zhu Ana M. Pelacho Teresa Capell Paul Christou 《Transgenic research》2010,19(2):165-180
Staple food crops, in particular cereal grains, are poor sources of key mineral nutrients. As a result, the world’s poorest
people, generally those subsisting on a monotonous cereal diet, are also those most vulnerable to mineral deficiency diseases.
Various strategies have been proposed to deal with micronutrient deficiencies including the provision of mineral supplements,
the fortification of processed food, the biofortification of crop plants at source with mineral-rich fertilizers and the implementation
of breeding programs and genetic engineering approaches to generate mineral-rich varieties of staple crops. This review provides
a critical comparison of the strategies that have been developed to address deficiencies in five key mineral nutrients—iodine,
iron, zinc, calcium and selenium—and discusses the most recent advances in genetic engineering to increase mineral levels
and bioavailability in our most important staple food crops. 相似文献
1000.