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81.
Thomas R. Alley 《Primates; journal of primatology》1980,21(3):416-429
The infants of many primate species possess distinctively coloured or patterned coats and flesh. Evolutionary theory, primate
ecology, and observational evidence all indicate that these distinctive characteristics may elicit attention, protection,
tolerance, and other forms of caregiving from older conspecifics. Such caretaking responses to infantile characteristics are
analogous to those found in other mammals and do not seem to require learning. 相似文献
82.
83.
Thomas Scheper 《Journal of industrial microbiology & biotechnology》1992,9(3-4):163-172
Summary A short review about the biosensor research activities for bioprocess monitoring in the F.R.G. after its reunification is given. The principles of biosensor applications are presented. In situ sensors and sensors based on the principles of flow injection analysis are studied. Some applications of a four-channel enzyme thermistor, bio-field effect transistors, and immunoanalysis systems for real process monitoring are presented. 相似文献
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Thomas Zeuthen 《The Journal of membrane biology》2010,234(2):57-73
Transport through lipids and aquaporins is osmotic and entirely driven by the difference in osmotic pressure. Water transport
in cotransporters and uniporters is different: Water can be cotransported, energized by coupling to the substrate flux by
a mechanism closely associated with protein. In the K+/Cl− and the Na+/K+/2Cl− cotransporters, water is entirely cotransported, while water transport in glucose uniporters and Na+-coupled transporters of nutrients and neurotransmitters takes place by both osmosis and cotransport. The molecular mechanism
behind cotransport of water is not clear. It is associated with the substrate movements in aqueous pathways within the protein;
a conventional unstirred layer mechanism can be ruled out, due to high rates of diffusion in the cytoplasm. The physiological
roles of the various modes of water transport are reviewed in relation to epithelial transport. Epithelial water transport
is energized by the movements of ions, but how the coupling takes place is uncertain. All epithelia can transport water uphill
against an osmotic gradient, which is hard to explain by simple osmosis. Furthermore, genetic removal of aquaporins has not
given support to osmosis as the exclusive mode of transport. Water cotransport can explain the coupling between ion and water
transport, a major fraction of transepithelial water transport and uphill water transport. Aquaporins enhance water transport
by utilizing osmotic gradients and cause the osmolarity of the transportate to approach isotonicity. 相似文献
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Silvana Molossi Mariano Elices Thomas Arrhenius Marlene Rabinovitch 《Journal of cellular physiology》1995,164(3):620-633
We previously reported infiltration of immune-inflammatory cells in coronary arteries from cardiac allografts, associated with increased endothelial and smooth muscle cell fibronectin synthesis regulated by interleukin (IL)-1b?. We now investigate, using a porcine endothelial-smooth muscle cell co-culture system, whether IL-1b?-stimulated fibronectin production is functionally important in lymphocyte transendothelial migration. Lymphocytes were harvested from porcine peripheral blood and, in the unactivated state or following activation with phorbol myristic acetate (PMA) and IL-2, were characterized by fluorescence-activated cell sorter (FACS) analysis and added to a confluent endothelial monolayer on the upper chamber of a transwell system. Endothelial cells, as well as smooth muscle cells (in the bottom of the chamber), were stimulated with IL-1b?. Then transendothelial lymphocyte migration was determined in the presence of CS1 and RGD (fibronectin) peptides, blocking α4b?1 and α5b?1 integrin receptors on lymphocyte surfaces, respectively. A 55-70% inhibition of lymphocyte migration was observed when compared to control peptides. The combination of CS1 and RGD peptides did not significantly enhance the inhibitory effect of either peptide alone. A similar decrease in lymphocyte transendothelial migration toward smooth muscle cells was documented using a monoclonal antibody to cellular fibronectin. Furthermore, using smooth muscle cell conditioned medium; we reproduced the enhanced transendothelial lymphocyte migration as well as the inhibition with blocking peptides or fibronectin antibodies. Our data suggest that cytokine-mediated fibronectin synthesis in vascular cells recruits inflammatory cells through interactions of specific peptides with cell surface α4b?1 α5b?1 integrins. © 1995 Wiley-Liss, Inc. 相似文献
90.