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191.
Hwang D Seo S Kim Y Kim C Shim S Jee S Lee S Jang M Kim M Yim S Lee SK Kang B Jang I Cho J 《Journal of biosciences》2007,32(4):723-735
To investigate whether selenium (Sel) treatment would impact on the onset of diabetes, we examined serum biochemical components
including glucose and insulin, endoplasmic reticulum (ER) stress and insulin signalling proteins, hepatic C/EBP-homologous
protein (CHOP) expression and DNA fragmentation in diabetic and non-diabetic conditions of non-obese diabetic (NOD) mice.
We conclude that (i) Sel treatment induced insulin-like effects in lowering serum glucose level in Sel-treated NOD mice, (ii)
Sel-treated mice had significantly decreased serum biochemical components associated with liver damage and lipid metabolism,
(iii) Sel treatment led to the activation of the ER stress signal through the phosphorylation of JNK and eIF2 protein and
insulin signal mechanisms through the phosphorylation of Akt and PI3 kinase, and (iv) Sel-treated mice were significantly
relieved apoptosis of liver tissues indicated by DNA fragmentation assay in the diabetic NOD group. These results suggest
that Sel compounds not only serve as insulin-like molecules for the downregulation of glucose level and the incidence of liver
damage, but may also have the potential for the development of new drugs for the relief of diabetes by activating the ER stress
and insulin signalling pathways. 相似文献
192.
Lee S Nahm M Lee M Kwon M Kim E Zadeh AD Cao H Kim HJ Lee ZH Oh SB Yim J Kolodziej PA Lee S 《Development (Cambridge, England)》2007,134(9):1767-1777
Axon extension and guidance require a coordinated assembly of F-actin and microtubules as well as regulated translation. The molecular basis of how the translation of mRNAs encoding guidance proteins could be closely tied to the pace of cytoskeletal assembly is poorly understood. Previous studies have shown that the F-actin-microtubule crosslinker Short stop (Shot) is required for motor and sensory axon extension in the Drosophila embryo. Here, we provide biochemical and genetic evidence that Shot functions with a novel translation inhibitor, Krasavietz (Kra, Exba), to steer longitudinally directed CNS axons away from the midline. Kra binds directly to the C-terminus of Shot, and this interaction is required for the activity of Shot to support midline axon repulsion. shot and kra mutations lead to weak robo-like phenotypes, and synergistically affect midline avoidance of CNS axons. We also show that shot and kra dominantly enhance the frequency of midline crossovers in embryos heterozygous for slit or robo, and that in kra mutant embryos, some Robo-positive axons ectopically cross the midline that normally expresses the repellent Slit. Finally, we demonstrate that Kra also interacts with the translation initiation factor eIF2beta and inhibits translation in vitro. Together, these data suggest that Kra-mediated translational regulation plays important roles in midline axon repulsion and that Shot functions as a direct physical link between translational regulation and cytoskeleton reorganization. 相似文献
193.
R. Anandham Kwan Ho Choi P. Indira Gandhi Woo Jong Yim Soo Jae Park Kyoung A Kim M. Madhaiyan Tong Min Sa 《World journal of microbiology & biotechnology》2007,23(8):1121-1129
Five phosphate-solubilizing bacteria (PSB) used in this study were isolated based on their ability to solubilize tricalcium
phosphate (TCP) in Pikovskaya’s medium. Among the tested bacterial strains Burkholderia sp. strain CBPB-HIM showed the highest solubilization (363 μg of soluble P ml−1) activity at 48 h of incubation. Further, this strain has been selected to assess its shelf life in nutrient-amended and
-unamended clay, rice bran and rock phosphate (RP) pellet-based granular formulation. The results showed that the maximum
viability of bacterium was observed in clay and rice bran (1:1) + 10% RP pellets than clay-RP pellets, irrespective of tested
storage temperatures. Further, clay and rice bran (1:1) + 10% RP pellets amended with 1% glucose supported the higher number
of cells compared to glycerol-amended and nutrient-unamended pellets. In this carrier solubilization of Morocco rock phosphate
(MRP) by Burkholderia sp. strain CBPB-HIM was also investigated. The maximum of water and bicarbonate extractable P (206 and 245 μg P g−1 of pellet respectively) was recorded in clay and rice bran (1:1) + 10% RP pellets amended with 1% glucose and glycerol respectively
on day 5 of incubation. Therefore, this study proved the possibility of developing granular inoculant technology combining
clay, rice bran and RP as substrates with phosphate-solubilizing Burkholderia. 相似文献
194.
Koo KD Kim MJ Kim S Kim KH Hong SY Hur GC Yim HJ Kim GT Han HO Kwon OH Kwon TS Koh JS Lee CS 《Bioorganic & medicinal chemistry letters》2007,17(15):4167-4172
Synthesis of a novel series of DPPIV inhibitors with 1,2,4- and 1,3,4-oxadiazolyl ketone derivatives and its structure-activity relationships are discussed. Compound 18h showed good inhibitory activity against DPPIV and favorable pharmacokinetic properties. In vivo pharmacodynamic efficacy and co-crystal structure of compound 18h with DPPIV is also described. 相似文献
195.
Divergence of genes encoding non-specific lipid transfer proteins in the poaceae family 总被引:1,自引:0,他引:1
The genes encoding non-specific lipid transfer proteins (nsLTPs), members of a small multigene family, show a complex pattern of expressional regulation, suggesting that some diversification may have resulted from changes in their expression after duplication. In this study, the evolution of nsLTP genes within the Poaceae family was characterized via a survey of the pseudogenes and unigenes encoding the nsLTP in rice pseudomolecules and the NCBI unigene database. nsLTP-rich regions were detected in the distal portions of rice chromosomes 11 and 12; these may have resulted from the most recent large segmental duplication in the rice genome. Two independent tandem duplications were shown to occur within the nsLTP-rich regions of rice. The genomic distribution of the nsLTP genes in the rice genome differs from that in wheat. This may be attributed to gene migration, chromosomal rearrangement, and/or differential gene loss. The genomic distribution pattern of nsLTP genes in the Poaceae family points to the existence of some differences among cereal nsLTP genes, all of which diverged from an ancient gene. The unigenes encoding nsLTPs in each cereal species are clustered into five groups. The somewhat different distribution of nsLTP-encoding EST clones between the groups across cereal species imply that independent duplication(s) followed by subfunctionalization (and/or neofunctionalization) of the nsLTP gene family in each species occurred during speciation. 相似文献
196.
Osawa Y Yim PD Xu D Panettieri RA Emala CW 《American journal of physiology. Lung cellular and molecular physiology》2007,292(6):L1414-L1421
Tumor necrosis factor (TNF)-alpha is a potent inflammatory cytokine implicated in the exacerbation of asthma. Chronic exposure to TNF-alpha has been reported to induce G protein-coupled receptor desensitization, but adenylyl cyclase sensitization, in airway smooth muscle cells by an unknown mechanism. Cyclic AMP, which is synthesized by adenylyl cyclases in response to G protein-coupled receptor signals, is an important second messenger involved in the regulation of the airway muscle proliferation, migration, and tone. In other cell types, TNF-alpha receptors transactivate the EGF receptor, which activates raf-1 kinase. Further studies in transfected cells show that raf-1 kinase can phosphorylate and activate some isoforms of adenylyl cyclase. Cultured human airway smooth muscle cells were treated with TNF-alpha in the presence or absence of inhibitors of prostaglandin signaling, protein kinases, or G(i) proteins. TNF-alpha caused a significant dose- (1-10 ng/ml) and time-dependent (24 and 48 h) increase in forskolin-stimulated adenylyl cyclase activity, which was abrogated by pretreatment with GW5074 (a raf-1 kinase inhibitor), was partially inhibited by an EGF receptor inhibitor, but was unaffected by pertussis toxin. TNF-alpha also increased phosphorylation of Ser(338) on raf-1 kinase, indicative of activation. IL-1beta and EGF sensitization of adenylyl cyclase activity was also sensitive to raf-1 kinase inhibition by GW5074. Taken together, these studies link two signaling pathways not previously characterized in human airway smooth muscle cells: TNF-alpha transactivation of the EGF receptor, with subsequent raf-1 kinase-mediated activation of adenylyl cyclase. 相似文献
197.
198.
199.
Kyung June Yim In-Tae Cha Hae-Won Lee Hye Seon Song Kil-Nam Kim Sung-Jae Lee Young-Do Nam Dong-Wook Hyun Jin-Woo Bae Sung-Keun Rhee Myung-Ji Seo Jong-Soon Choi Hak-Jong Choi Seong Woon Roh Daekyung Kim 《Antonie van Leeuwenhoek》2014,105(3):603-612
A novel, red-pigmented, pleomorphic and short rod-shaped haloarchaeon, designated B8T, was isolated from a salt-fermented seafood. Strain B8T was found to be able to grow at 20–45 °C, in the presence of 15–30 % (w/v) NaCl and at pH 7.0–9.0. The optimum requirements were found to be a temperature range of 35–40 °C, pH 8.0 and the presence of 25 % NaCl. The cells of strain B8T were observed to be Gram-staining negative and lysed in distilled water. Anaerobic growth did not occur in the presence of nitrate, l-arginine, dimethyl sulfoxide or trimethylamine N-oxide. The catalase and oxidase activities were found to be positive and nitrate was reduced in aerobic conditions. Tween 20, 40 and 80 were found to be hydrolyzed, whereas casein, gelatin and starch were not hydrolyzed. Indole or H2S was not formed and urease activity was not detected. A phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain B8T is most closely related to members of the genus Halorubrum in the family Halobacteriaceae. Strain B8T was found to have three 16S rRNA genes, rrnA, rrnB and rrnC; similarities between the 16S rRNA gene sequences are 99.0–99.8 %. Strain B8T shared 99.0 % 16S rRNA gene sequence similarity with Halorubrum (Hrr.) lipolyticum JCM 13559T and Hrr. saccharovorum DSM 1137T, 98.8 % with Hrr. kocurii JCM 14978T, 98.3 % with Hrr. lacusprofundi DSM 5036T, 98.0 % with Hrr. arcis JCM 13916T, 97.7 % with Hrr. aidingense JCM 13560T and 97.0 % with Hrr. aquaticum JCM 14031T, as well as 93.7–96.5 % with other type strains in the genus Halorubrum. The RNA polymerase subunit B′ gene sequence similarity of strain B8T with Hrr. kocurii JCM 14978T is 97.2 % and lower with other members of the genus Halorubrum. DNA–DNA hybridization experiments showed that strain B8T shared equal or lower than 50 % relatedness with reference species in the genus Halorubrum. The genomic DNA G+C content of strain B8T was determined to be 64.6 mol%. The major isoprenoid quinone of strain B8T was identified as menaquinone-8 and the major polar lipids as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, sulfated mannosyl glucosyl diether and an unidentified phospholipid. Based on this polyphasic taxonomic study, strain B8T is considered to represent a new species in the genus Halorubrum, for which the name Hrr. halophilum sp. nov. is proposed. The type strain is B8T (=JCM 18963T = CECT 8278T). 相似文献
200.
Gene conversions and crossovers are related products of the repair of double-stranded DNA breaks by homologous recombination. Most previous studies of mitotic gene conversion events have been restricted to measuring conversion tracts that are <5 kb. Using a genetic assay in which the lengths of very long gene conversion tracts can be measured, we detected two types of conversions: those with a median size of ∼6 kb and those with a median size of >50 kb. The unusually long tracts are initiated at a naturally occurring recombination hotspot formed by two inverted Ty elements. We suggest that these long gene conversion events may be generated by a mechanism (break-induced replication or repair of a double-stranded DNA gap) different from the short conversion tracts that likely reflect heteroduplex formation followed by DNA mismatch repair. Both the short and long mitotic conversion tracts are considerably longer than those observed in meiosis. Since mitotic crossovers in a diploid can result in a heterozygous recessive deleterious mutation becoming homozygous, it has been suggested that the repair of DNA breaks by mitotic recombination involves gene conversion events that are unassociated with crossing over. In contrast to this prediction, we found that ∼40% of the conversion tracts are associated with crossovers. Spontaneous mitotic crossover events in yeast are frequent enough to be an important factor in genome evolution. 相似文献