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Neuroprotective Effect of Chitosan Oligosaccharide on Hypoxic-Ischemic Brain Damage in Neonatal Rats
Wei Wu Wei Wei Min Lu Xiaoyun Zhu Ning Liu Yang Niu Tao Sun Yuxiang Li Jianqiang Yu 《Neurochemical research》2017,42(11):3186-3198
Neonatal hypoxic-ischemic brain damage (HIBD) is one of the leading causes of neonatal mortality and permanent neurological disability worldwide and the effective treatment strategies are not yet available. It has been demonstrated that Chitosan oligosaccharide (COS) exerts protective effect in vitro ischemic brain injury. However, no information is available on possible effects of COS on neonatal HIBD. To investigate the hypothesis of the potential neuroprotective effect of COS on the brain injury due to HIBD, 7-day-old Sprague–Dawley rats were treated with left carotid artery ligation followed by exposure to 8% oxygen (balanced with nitrogen) for 2.5 h at 37?°C. After COS treatment, the cerebral damage was measured by behavior tasks, 2,3,5-triphenyltetrazolium chloride(TTC), Hematoxyline-Eosin(HE), Nissl and Fluoro-Jade B(FJB)staining. In addition, the oxidative stress were assayed with ipsilateral hemisphere homogenates. Immunofluorescence staining were used to examine the activation of the astrocyte and microglia. Expression of inflammatory-related proteins were analyzed by western-blot analysis. In this study we found that administration of COS ameliorated early neurological reflex behavior, significantly reduce brain infarct volume and attenuated neuronal cell injury and degeneration. Furthermore, COS markedly decreased the level of MDA, lactic acid and increased SOD, GSH-Px and T-AOC. COS attenuated hypoxic-ischemic induced up-regulation of expressions of interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), meanwhile it dramatically increased the interleukin-10 (IL-10). These results suggest that COS exerts neuroprotection on hypoxic-ischemic brain damage in neonatal rats, it implies COS might be a potential therapeutic for the treatment of HIBD. 相似文献
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Splenic gene expression profiling in White Leghorn layer inoculated with the Salmonella enterica serovar Enteritidis 下载免费PDF全文
Salmonella enterica serovar Enteritidis (SE) is a foodborne pathogen that can threaten human health through contaminated poultry products. Live poultry, chicken eggs and meat are primary sources of human salmonellosis. To understand the genetic resistance of egg‐type chickens in response to SE inoculation, global gene expression in the spleen of 20‐week‐old White Leghorn was measured using the Agilent 4 × 44 K chicken microarray at 7 and 14 days following SE inoculation (dpi). Results showed that there were 1363 genes significantly differentially expressed between inoculated and non‐inoculated groups at 7 dpi (I7/N7), of which 682 were up‐regulated and 681 were down‐regulated genes. By contrast, 688 differentially expressed genes were observed at 14 dpi (I14/N14), of which 371 were up‐regulated genes and 317 were down‐regulated genes. There were 33 and 28 immune‐related genes significantly differentially expressed in the comparisons of I7/N7 and I14/N14 respectively. Functional annotation revealed that several Gene Ontology (GO) terms related to immunity were significantly enriched between the inoculated and non‐inoculated groups at 14 dpi but not at 7 dpi, despite a similar number of immune‐related genes identified between I7/N7 and I14/N14. The immune response to SE inoculation changes with different time points following SE inoculation. The complicated interaction between the immune system and metabolism contributes to the immune responses to SE inoculation of egg‐type chickens at 14 dpi at the onset of lay. GC, TNFSF8, CD86, CD274, BLB1 and BLB2 play important roles in response to SE inoculation. The results from this study will deepen the current understanding of the genetic response of the egg‐type chicken to SE inoculation at the onset of egg laying. 相似文献
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Three saponins from Oxytropis species. 总被引:2,自引:0,他引:2
Three flavonoids and three saponins have been isolated from Oxytropis species. Their structures were determined as isorhamnetin-3-O-beta-D-glucoside, rhamnetin-3-O-beta-D-galactoside, apigenin, 3-O-[alpha-L-rhamnopyranosyl (1----2)-beta-D-glucopyranosyl(1----4)-beta-D-glucuronopyranosyl]+ ++soyasapogenol B, 3-O-[beta-D-glucopyranosyl(1----2)-beta-D-glucuronopyranosyl] azukisapogenol and a new saponin 3-O-[beta-D-glucopyranosyl(1----2)-beta-D-glucopyranosyl]-25-O-alpha-L- rhamnopyranosyl-(20S,24S)-3 beta,16 beta, 20,24,25-pentahydroxy-9,19-cycloanostane. 相似文献
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W. D. Roof H. Q. Fang K. D. Young Jianling Sun & Ry Young 《Molecular microbiology》1997,25(6):1031-1046
slyD encodes a 196 amino acid polypeptide that is a member of the FKBP family of cis–trans peptidyl–prolyl isomerases (PPIases). slyD mutations affect plaque formation by the phage φX174 by blocking the action of the phage lysis protein E. Here we describe the selection of a set of spontaneous slyD mutations conferring resistance to the expression of gene E from a plasmid. These mutations occur disproportionately in residues of SlyD that, based on the structure of the prototype mammalian FKBP12, make ligand contacts with immunosuppressing drug molecules or are conserved in other FKBP proteins. A wide variation in the plating efficiency of φX174 on these E R strains is observed, relative to the parental, indicating that these alleles differ widely in residual SlyD activity. Moreover, it is found that slyD mutations cause significant growth rate defects in Escherichia coli B and C backgrounds. Finally, overexpression of slyD causes filamentation of the host. Thus, among the FKBP genes found in organisms across the evolutionary spectrum, slyD is unique in having three distinct drug-independent phenotypes. 相似文献
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Unconventional Sequence Requirement for Viral Late Gene Core Promoters of Murine Gammaherpesvirus 68
Elaine Wong-Ho Ting-Ting Wu Zoe H. Davis Bingqing Zhang Jian Huang Hao Gong Hongyu Deng Fenyong Liu Britt Glaunsinger Ren Sun 《Journal of virology》2014,88(6):3411-3422
Infection with the human gammaherpesviruses, Epstein-Barr virus (EBV) and Kaposi''s sarcoma-associated herpesvirus (KSHV), is associated with several cancers. During lytic replication of herpesviruses, viral genes are expressed in an ordered cascade. However, the mechanism by which late gene expression is regulated has not been well characterized in gammaherpesviruses. In this study, we have investigated the cis element that mediates late gene expression during de novo lytic infection with murine gammaherpesvirus 68 (MHV-68). A reporter system was established and used to assess the activity of viral late gene promoters upon infection with MHV-68. It was found that the viral origin of lytic replication, orilyt, must be on the reporter plasmid to support activation of the late gene promoter. Furthermore, the DNA sequence required for the activation of late gene promoters was mapped to a core element containing a distinct TATT box and its neighboring sequences. The critical nucleotides of the TATT box region were determined by systematic mutagenesis in the reporter system, and the significance of these nucleotides was confirmed in the context of the viral genome. In addition, EBV and KSHV late gene core promoters could be activated by MHV-68 lytic replication, indicating that the mechanisms controlling late gene expression are conserved among gammaherpesviruses. Therefore, our results on MHV-68 establish a solid foundation for mechanistic studies of late gene regulation. 相似文献
9.
Zhemin Li Genhai Zhao Hui Liu Yugang Guo Hefang Wu Xiaowen Sun Xihua Wu Zhiming Zheng 《Journal of industrial microbiology & biotechnology》2017,44(7):973-985
Prenylated quinones, especially menaquinones, have significant physiological activities, but are arduous to synthesize efficiently. Due to the relaxed aromatic substrate specificity and prenylation regiospecificity at the ortho- site of the phenolic hydroxyl group, the aromatic prenyltransferase NovQ from Streptomyces may be useful in menaquinone synthesis from menadione. In this study, NovQ was overexpressed in Pichia pastoris. After fermentation optimization, NovQ production increased by 1617%. Then the different effects of metal ions, detergents and pH on the activity of purified NovQ were investigated to optimize the prenylation reaction. Finally, purified NovQ and cells containing NovQ were used for menadione prenylation in vitro and in vivo, respectively. Menaquinone-1 (MK-1) was detected as the only product in vitro with γ,γ-dimethylallyl pyrophosphate and menadione hydroquinol substrates. MK-3 at a concentration of 90.53 mg/L was detected as the major product of whole cell catalysis with 3-methyl-2-buten-1-ol and menadione hydroquinol substrates. This study realized whole cell catalysis converting menadione to menaquinones. 相似文献
10.
Weigang Cui Songtao Wang Zhongping Wang Zhiyong Wang Chunli Sun Yinghua Zhang 《Neurochemical research》2017,42(11):3052-3060
Amyloid plaques and neurofibrillary tangles are pathologic hallmarks of Alzheimer’s disease (AD). Endoplasmic reticulum (ER) stress has been implicated in the loss of neurons in AD. The phosphatase and tensin homolog deleted on chromosome ten (PTEN) plays an important role in regulating neuronal survival processes. However, the direct effects of the PTEN on ER stress and apoptosis in AD have not been elucidated. In this study, we demonstrate that the expression of PTEN and ER stress related proteins, GRP78 and CHOP, increased in APP/PS1 transgenic AD mice compared with WT mice. A PTEN inhibitor, dipotassium bisperoxo-(5-hydroxypyridine-2-carboxyl)-oxovanadate (bpv) could decrease apoptosis, induce AKT phosphorylation and inhibit the ER stress response proteins in hippocampus in APP/PS1 transgenic AD model mice. Furthermore, treatment with the specific PI3K inhibitor, LY294002, significantly blocked the anti-apoptotic effects of bpv in AD mice. The expression in GRP78, CHOP and apoptosis levels by bpv was reversed after PI3K inhibitor treatment. Taken together, our results indicate that the neuroprotective role of bpv involves the suppression of ER stress via the activation of the PI3K/AKT signalling pathways in APP/PS1 transgenic AD model mice. 相似文献