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991.
Ohsawa K Sanagi T Nakamura Y Suzuki E Inoue K Kohsaka S 《Journal of neurochemistry》2012,121(2):217-227
The extension of microglial processes toward injured sites in the brain is triggered by the stimulation of the purinergic receptor P2Y(12) by extracellular ATP. We recently showed that P2Y(12) stimulation by ATP induces microglial process extension in collagen gels. In the present study, we found that a P2Y(12) agonist, 2-methylthio-ADP (2MeSADP), failed to induce the process extension of microglia in collagen gels and that co-stimulation with adenosine, a phosphohydrolytic derivative of ATP, and 2MeSADP restored the chemotactic process extension. An adenosine A3 receptor (A3R)-selective agonist restored the chemotactic process extension, but other receptor subtype agonists did not. The removal of adenosine by adenosine deaminase and the blocking of A3R by an A3R-selective antagonist inhibited ADP-induced process extension. The A3R antagonist inhibited ADP-induced microglial migration, and an A3R agonist promoted 2MeSADP-stimulated migration. ADP and the A3R agonist activated Jun N-terminal kinase in microglia, and a Jun N-terminal kinase inhibitor inhibited the ADP-induced process extension. An RT-PCR analysis showed that A1R and A3R were expressed by microglia sorted from adult rat brains and that the A2AR expression level was very low. These results suggested that A3R signaling may be involved in the ADP-induced process extension and migration of microglia. 相似文献
992.
Miyazaki T Takenaka T Inoue T Sato M Miyajima Y Nodera M Hanyu M Ohno Y Shibazaki S Suzuki H 《Biological trace element research》2012,145(3):375-381
Zinc deficiency leads to decreased cellular immune responses. The overproduction of nitrogen species derived from inducible
nitric oxide synthase (iNOS), its enzyme, and interleukine-1 beta (IL-1β), and inflammatory cytokine have been implicated
in immune responses. The goal of this study was to investigate the effects of lipopolysaccharide (LPS)-induced changes in
NO metabolites, iNOS, and IL-1β protein expression in the lungs of zinc-deficient rats. Male Sprague–Dawley rats (body weight,
100 g) were divided into two groups and were fed either a zinc-deficient diet (ZnD) or a zinc-containing diet (Cont). After
4 weeks on these diets, rats received a 10-mg/kg dose of LPS injected via the tail vein and were then maintained for an additional
72 h. To determine total NO concentrations in the blood, serum zinc concentration, iNOS protein expression, IL-1β, and iNOS
immunohistochemistry, blood and lung samples were obtained at pre-LPS injection, 5, 24, and 72 h after injection. Total NO
levels were significantly increased at 5, at 24, and at 72 h after LPS injection compared with pre-LPS injection level in
ZnD group; significant changes in total NO levels was elevated at 5 h from at pre-LPS level but not significant changes from
basal level at 24 and 72 h in the control group. Based on western blot analyses and immunohistochemistry, clear bands indicating
iNOS and IL-1β protein expression and iNOS antibody-stained inflammatory cells were detected at 5 and 24 h in the ZnD group
and 5 h in the Cont group, not observed at 24 and 72 h in the control group. These results suggest that zinc deficiency induces
overexpression of iNOS and IL-1β proteins from inflammatory cells around the alveolar blood vessels, resulting in overproduction
of total NO and persisted inflammatory response in the zinc-deficient rat lung. Taken together, overexpression of LPS-induced
iNOS, overproduction of iNOS-derived NO, and overexpression of IL-1β may induce nitrosative and oxidative stresses in the
lung, and these stresses may be involved low immunity of zinc deficiency states. 相似文献
993.
Sekine F Horiguchi K Kashino Y Shimizu Y Yu LJ Kobayashi M Wang ZY 《Photosynthesis research》2012,111(1-2):9-18
In this study, gene sequences coding for the light-harvesting (LH) 2 polypeptides from a thermophilic purple sulfur bacterium Thermochromatium tepidum are reported and characterization of the LH2 complex is described. Three sets of pucBA genes have been identified, and the gene products have been analyzed by electrophoresis and reversed-phase chromatography. The result shows that all of the genes are expressed but the distribution of the expression is not uniform. The gene products undergo post-translational modification, where two of the β-polypeptides appear to be N-terminally methylated. Absorption spectrum of the purified LH2 complex exhibits Q y transitions at 800 and 854?nm in dodecyl β-maltopyranoside solution, and the circular dichroism spectrum shows a “molischianum”-like characteristic. No spectral change was observed for the LH2 when the bacterium was cultured under different conditions of light intensity. In lauryl dimethylamine N-oxide (LDAO) solution, significant changes in the absorption spectrum were observed. The B850 peak decreased and blue-shifted with increasing the LDAO concentration, whereas the B800 intensity increased without change in the peak position. The spectral changes can be partially or almost completely reversed by addition of metal ions, and the divalent cations seem to be more effective. The results indicate that ionic interactions may exist between LH2, detergent molecules and metal ions. Possible mechanisms involved in the detergent- and cation-induced spectral changes are discussed. 相似文献
994.
Hara KY Kim S Yoshida H Kiriyama K Kondo T Okai N Ogino C Fukuda H Kondo A 《Applied microbiology and biotechnology》2012,93(4):1495-1502
Glutathione is a valuable tri-peptide that is widely used in the pharmaceutical, food, and cosmetic industries. Glutathione
is produced industrially by fermentation using Saccharomyces cerevisiae, and supplementation of fermentation with several amino acids can increase intracellular GSH content. More recently, however,
focus has been given to protein as a resource for biofuel and fine chemical production. We demonstrate that expression of
a protease on the cell surface of S. cerevisiae enables the direct use of keratin and soy protein as a source of amino acids and that these substrates enhanced intracellular
GSH content. Furthermore, fermentation using soy protein also enhanced cell concentration. GSH fermentation from keratin and
to a greater extent from soy protein using protease-displaying yeast yielded greater GSH productivity compared to GSH fermentation
with amino acid supplementation. This protease-displaying yeast is potentially applicable to a variety of processes for the
bio-production of value-added chemicals from proteinaceous biomass resources. 相似文献
995.
Masuyama H Nobumoto E Inoue S Hiramatsu Y 《American journal of physiology. Endocrinology and metabolism》2012,302(6):E687-E693
Adiponectin was reported recently to have roles in the pathophysiology of preeclampsia. Moreover, elevation of adiponectin and brain natriuretic peptide (BNP) has been observed in preeclampsia. We examined the possible links between adiponectin and BNP in the pathophysiology of preeclampsia. We performed a cross-sectional study in 56 preeclampsia patients and 56 controls matched for gestational age and body mass index. The BNP, leptin, and adiponectin levels were measured by ELISA, and their mRNA expressions were evaluated in omental adipose tissue by real-time PCR. The effects of BNP on adiponectin and leptin mRNA expression and secretion were investigated in primary cultures of adipocytes from obese and normal-weight women. The BNP, adiponectin, and leptin levels were significantly higher in preeclampsia patients compared with controls. The adiponectin level was increased significantly in normal-weight preeclampsia patients compared with overweight preeclampsia patients. Adiponectin mRNA expression was increased significantly in adipose tissues of preeclampsia patients compared with controls and was also increased significantly in normal-weight preeclampsia patients compared with overweight preeclampsia patients, whereas leptin was not. BNP and adiponectin showed significant positive correlations in both normal-weight and overweight preeclampsia patients. BNP had a significantly weaker effect on adiponectin in overweight compared with normal-weight preeclampsia patients. Moreover, BNP had a weaker effect on adiponectin production in adipocytes from overweight women compared with adipocytes from normal-weight women using primary culture of human adipocytes. These data suggested that BNP may play a role in hyperadiponectinemia of preeclampsia patients. The weaker effect of BNP on adiponectin production may participate in the pathophysiology of overweight preeclampsia patients. 相似文献
996.
Yamada Y Muraki A Oie M Kanegawa N Oda A Sawashi Y Kaneko K Yoshikawa M Goto T Takahashi N Kawada T Ohinata K 《American journal of physiology. Endocrinology and metabolism》2012,302(4):E433-E440
Soymorphin-5 (YPFVV) derived from soybean β-conglycinin β-subunit is a μ-opioid agonist peptide having anxiolytic-like activity. Here, we show that soymorphin-5 improves glucose and lipid metabolism after long-term oral administration to KKAy mice, a type 2 diabetes model animal. Soymorphin-5 inhibited hyperglycemia without an increase in plasma insulin levels in KKAy mice. Soymorphin-5 also decreased plasma and liver triglyceride (TG) levels and liver weight, suggesting that soymorphin-5 improved lipid metabolism. Soymorphin-5 increased plasma adiponectin concentration and liver mRNA expression of AdipoR2, a subtype of adiponectin receptor that is involved in stimulating the peroxisome proliferator-activated receptor (PPAR)α pathway and fatty acid β-oxidation. The expressions of the mRNA of PPARα and its target genes acyl-CoA oxidase, carnitine palmitoyltransferase 1 A, and uncoupling protein-2, in the liver were also increased after oral administration of soymorphin-5. Furthermore, des-Tyr-soymorphin-5 (PFVV) without μ-opioid and anxiolytic-like activities did not decrease blood glucose levels in KKAy mice. These results suggest that μ-opioid peptide soymorphin-5 improves glucose and lipid metabolism via activation of the adiponectin and PPARα system and subsequent increases of β-oxidation and energy expenditure in KKAy mice. 相似文献
997.
998.
Shahrizad Yusof Ahmad Ismail Tomoko Koito Masato Kinoshita Koji Inoue 《Environmental Biology of Fishes》2012,93(1):43-49
Among ricefishes of the genus Oryzias, the Javanese medaka (O. javanicus) and the Indian medaka (O. dancena) are highly adaptable to seawater. Although wide distribution of the two species in the brackish waters of South and South-East
Asia has been reported, their habitat preference remains unknown. We surveyed 12 sites in five estuarial areas of the west
coast of Peninsular Malaysia from Kuala Gula to Tanjung Piai. Both species were found in all five areas, suggesting their
distribution throughout the west coast of Peninsular Malaysia. This is the southernmost-recorded appearance of O. dancena, to the best of our knowledge. However, the habitats of the two species were essentially separated: of the 12 surveyed sites,
the species were found in co-existence at only two sites, and one or the other species was found alone at the remaining 10
sites. We compared temperature, salinity, pH, and dissolved oxygen (DO) at the sampling sites and found that the habitat of
O. javanicus is with higher salinity and DO. The salinity and DO at the sites of co-existence are near the lowest values found at the
O. javanicus-only sites, and the highest values at the O. dancena-only sites. These results suggest that O. javanicus and O. dancena habitats are essentially separated; the former prefers hyperosmotic conditions while the latter prefers hypoosmotic conditions,
and the latter may be more tolerant of hypoxia. The two sites of co-existence are points of contact between the species’ separate
distribution areas. 相似文献
999.
To examine the potential linkage between sex-biased growth and dispersal in demersal fish, we studied the movement distance and growth of tag-recaptured sablefish (Anoplopoma fimbria). Tagging was conducted by teams from Japan and the United States. From 1980 to 1984, 58,918 sablefish were captured by Japanese vessels and tagged with anchor tags, and between 1980 and 2007, 3319 sablefish were recaptured in the Bering Sea and northeastern Pacific. Of these 3319 fish, we analyzed data on 659 individuals for which we have reliable data on recapture location, sex and fork length at the time of release and recapture, and elapsed time longer than 10?days. Annual growth increments (mean±S.D.) were 2.5?±?6.5?cm (males) and 3.5?±?8.6?cm (females), and the movement distances (assumed to be straight) were 712?±?800?km (males) and 877?±?920?km (females). Females grew larger and moved longer distances than males. We calculated the growth increment deviation that accounted for the effects of elapsed time, curvilinear growth, and initial fork length at release using a von Bertalanffy growth model. The growth increment deviation increased significantly with the distance moved over elapsed time. In addition, the relationship between distance moved over elapsed time and the growth deviation differed significantly between sexes; females grew faster than males at a given movement distance. We suggest that female-biased dispersal is a factor generating female-biased growth in sablefish. 相似文献
1000.
Tsukamoto K Arimitsu H Ochi S Nakamura K Tanaka Y Nuemket N Taniguchi K Kozaki S Tsuji T 《Microbiology and immunology》2012,56(10):664-672
Botulinum neurotoxins (BoNTs) inhibit neurotransmitter release at peripheral nerve terminals. They are serologically classified from A to G, C/D and D/C mosaic neurotoxins forming further subtypes of serotypes C and D. Cultured primary neurons, as well as neuronal cell lines such as PC12 and Neuro-2a, are often utilized in cell-based experiments on the toxic action of botulinum toxins. However, there are very few reports of the use of neural cell lines for studying BoNTs/C and D. In addition, the differentiated P19 neuronal cell line, which possesses cholinergic properties, has yet to be tested for its susceptibility to BoNTs. Here, the responsiveness of differentiated P19 cells to BoNT/C and BoNT/DC is reported. Both BoNT/C and BoNT/DC were shown to effectively bind to, and be internalized by, neurons derived from P19 cells. Subsequently, the intracellular substrates for BoNT/C and BoNT/DC were cleaved by treatment of the cells with the toxins in a ganglioside-dependent manner. Moreover, P19 neurons exhibited high sensitivity to BoNT/C and BoNT/DC, to the same extent as cultured primary neurons. These findings suggest that differentiated P19 cells possess full sensitivity to BoNT/C and BoNT/DC, thus making them a novel susceptible cell line for research into BoNTs. 相似文献