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991.
Sargassum is a cosmopolitan brown algal genus spanning the three ocean basins of the Atlantic, Pacific and Indian Oceans, inhabiting temperate, subtropical and tropical habitats. Sargassum has been postulated to have originated in the Oligocene epoch approximately 30 mya according to a broad phylogenetic analysis of brown macroalgae, but its diversification to become one of the most widespread and speciose macroalgal genera remains unclear. Here, we present a Bayesian molecular clock study, which analyzed data from the order Fucales of the brown algal crown radiation (BACR) group to reconstruct a time-calibrated phylogeny of the Sargassum clade. Our phylogeny included a total of 120 taxa with 99 Sargassum species sampled for three molecular markers – ITS-2, cox3 and rbcLS – calibrated with an unambiguous Sargassaceae fossil from between the lower and middle Miocene. The analysis revealed a much later origin of Sargassum than expected at about 6.7 mya, with the genus diversifying since approximately 4.3 mya. Current geographic distributions of Sargassum species were then analyzed in conjunction with the time-calibrated phylogeny using the dispersal-extinction-cladogenesis (DEC) model to estimate ancestral ranges of clades in the genus. Results strongly support origination of Sargassum in the Central Indo-Pacific (CIP) region with subsequent independent dispersal events into other marine realms. The longer history of diversification in the ancestral CIP range could explain the much greater diversity there relative to other marine areas today. Analyses of these dynamic processes, when fine-tuned to a higher spatial resolution, enable the identification of evolutionary hotspots and provide insights into long-term dispersal patterns. 相似文献
992.
本文报导五加科一新属,人参本属Chengiopanax Shang et J.Y.Huang,新组合2种,即华人参木Ch.fargesii(Franch.)Shang et J.Y.Hung及人参木Ch.sciadophylloides(Franch.et Sav.)Shang et J.Y.Huang。 相似文献
993.
Li J Zhao GZ Huang HY Qin S Zhu WY Zhao LX Xu LH Zhang S Li WJ Strobel G 《Antonie van Leeuwenhoek》2012,101(3):515-527
Endophytic actinobacteria isolated from Artemisia annua were characterized and evaluated for their bioactivities. A total of 228 isolates representing at least 19 different genera
of actinobacteria were obtained and several of them seemed to be novel taxa. An evaluation of antimicrobial activity showed
that more isolates possessed activity towards plant pathogens than activity against other pathogenic bacteria or yeasts. High
frequencies of PCR amplification were obtained for type I polyketide synthases (PKS-I, 21.1%), type II polyketide synthases
(PKS-II, 45.2%) and nonribosomal peptide synthetases (NRPS, 32.5%). The results of herbicidal activity screening indicated
that 19 out of 117 samples of fermentation broths completely inhibited the germination of Echinochloa crusgalli. This study indicated that endophytic actinobacteria associated with A. annua are abundant and have potentially beneficial and diverse bioactivities which should be pursued for their biotechnical promise. 相似文献
994.
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996.
Li Q Huang XJ He W Ding J Jia JT Fu G Wang HX Guo LJ 《Cellular and molecular neurobiology》2009,29(2):169-180
We previously reported that inhibition of Rho-kinase (ROCK) by hydroxyl fasudil improves cognitive deficit and neuronal damage
in rats with chronic cerebral ischemia (Huang et al., Cell Mol Neurobiol 28:757–768, 2008). In this study, fasudil mesylate
(FM) was investigated for its neuroprotective potential in rats with ischemia following middle cerebral artery occlusion (MCAO)
and reperfusion. The effect of fasudil mesylate was also studied in rat brain cortical and hippocampal slices treated with
oxygen-glucose deprivation (OGD) injury. Gross anatomy showed that cerebral infarct size, measured with 2,3,5-triphenyltetrazolium
chloride (TTC) staining, was significantly smaller in the FM-treated than in the non-FM-treated ischemic rats. In the brain
regions vulnerable to ischemia of ischemic rats, fasudil mesylate was also found to significantly restore the enzyme protein
expression level of endothelial nitric oxide synthase (eNOS), which was decreased in ischemia. However, it remarkably reduced
the protein synthesis of inducible nitric oxide synthase (iNOS) that was induced by ischemia and reperfusion. In rat brain
slices treated with OGD injury, fasudil mesylate increased the neuronal cell viability by 40% for cortex and by 61% for hippocampus,
respectively. Finally, in the presence of OGD and fasudil mesylate, superoxide dismutase (SOD) activity was increased by 50%
for cortex and by 58% for hippocampus, compared to OGD only group. In conclusion, our in vivo study showed that fasudil mesylate
not only decreased neurological deficit but also reduced cerebral infarct size, possibly and at least partially by augmenting
eNOS protein expression and inhibiting iNOS protein expression after ischemia-reperfusion.
Xian-Ju Huang contributed equally to this article. 相似文献
997.
Y C Huang B N Wu J L Yeh S J Chen J C Liang Y C Lo I J Chen 《Bioorganic & medicinal chemistry》2001,9(7):1739-1746
A series of vanilloid-type beta-adrenoceptor blockers derived from antioxidant traditional Chinese herbal medicines were synthesized and tested for their antioxidant and adrenoceptor antagonistic activities. They all possessed significant beta-adrenoceptor blocking activities under in vitro experiments and radioligand binding assays. In addition, some compounds were further examined in in vivo tests and produced antagonist effects matching that of propranolol and labetalol by measurements of antagonism toward (-)isoproterenol-induced tachycardia and (-)phenylephrine-induced pressor responses in anesthetized rats. Furthermore, all of the compounds had antioxidant effects inherited from their original structures. In conclusion, compound 11 had the most potent beta-adrenoceptors blocking activity, 12 and 13 possessed high cardioselectivity, whereas 14, 15 and 16 possessed additional alpha-adrenoceptor blocking activity and 15 is the most effective antioxidant of all. The antioxidant activity may be due to their alpha and beta unsaturated side chain at position 1 and ortho-substituted methoxy moiety on 4-phenoxyethylamine. 相似文献
998.
Xu D Huang W Li Y Wang H Huang H Cui X 《The Plant journal : for cell and molecular biology》2012,69(5):792-808
The mitotic cell cycle in higher eukaryotes is of pivotal importance for organ growth and development. Here, we report that Elongator, an evolutionarily conserved histone acetyltransferase complex, acts as an important regulator of mitotic cell cycle to promote leaf patterning in Arabidopsis. Mutations in genes encoding Elongator subunits resulted in aberrant cell cycle progression, and the altered cell division affects leaf polarity formation. The defective cell cycle progression is caused by aberrant DNA replication and increased DNA damage, which activate the DNA replication checkpoint to arrest the cell cycle. Elongator interacts with proliferating cell nuclear antigen (PCNA) and is required for efficient histone 3 (H3) and H4 acetylation coupled with DNA replication. Levels of chromatin-bound H3K56Ac and H4K5Ac known to associate with replicons during DNA replication were reduced in the mutants of both Elongator and chromatin assembly factor 1 (CAF-1), another protein complex that physically interacts with PCNA for DNA replication-coupled chromatin assembly. Disruptions of CAF-1 also led to severe leaf polarity defects, which indicated that Elongator and CAF-1 act, at least partially, in the same pathway to promote cell cycle progression. Collectively, our results demonstrate that Elongator is an important regulator of mitotic cell cycle, and the Elongator pathway plays critical roles in promoting leaf polarity formation. 相似文献
999.
Kuen-Feng Chen Kuan-Chuan Pao Jung-Chen Su Yi-Chieh Chou Chun-Yu Liu Hui-Ju Chen Jui-Wen Huang InKi Kim Chung-Wai Shiau 《Bioorganic & medicinal chemistry》2012,20(20):6144-6153
Cancerous inhibitor of PP2A (CIP2A) is a novel human oncoprotein that inhibits PP2A, contributing to tumor aggressiveness in various cancers. Several studies have shown that downregulation of CIP2A by small molecules reduces PP2A-dependent phosphorylation of Akt and induces cell death. Here, a series of mono- and di-substituted quinazoline and pyrimidine derivatives based on the skeleton of erlotinib (an EGFR inhibitor) were synthesized and their bioactivities against hepatocellular carcinoma were evaluated. The di-substituted quinazoline and pyrimidine derivatives were more potent inhibitors of cancer-cell proliferation than the mono-substituted derivatives. In particular, compound 1 with chloride at position 2 of quinazoline was as potent as erlotinib in inducing cell death but no inhibition for EGFR activity. Further assays confirmed a correlation between cell death, and CIP2A and Akt inhibition by these derivatives. Among all the derivatives, compounds 19 and 22 showed the most potent antiproliferative activities and the strongest inhibition of CIP2A and p-Akt expression. 相似文献
1000.