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981.
982.
Yetong Ouyang Dongling Li Han Wang Zhigang Wan Qinghua Luo Yuqin Zhong Min Yin Zhengfang Qing Zhengyu Li Bing Bao Zhiying Chen Xiaoping Yin Ling‐Qiang Zhu 《Aging cell》2019,18(6)
Intracerebral haemorrhage (ICH) is a severe neurological disorder caused by bleeding within the brain tissue. Inflammation has been implicated in ICH pathogenesis and is a potential therapeutic target for ICH. Haemin, an activator of haem oxygenase‐1 (HO‐1), rapidly increases HO‐1 protein expression and activity and has been shown to distinctly affect anti‐inflammatory functions after central nervous system (CNS) injury. However, less is known about the mechanisms that underlie the anti‐inflammatory effects of haemin in aged rats post‐ICH. Here, we performed microarray analysis to identify miRNAs that respond strongly to HO‐1 regulation in ICH rats and found that miR‐21‐5p induced the most significant change. Using Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and Gene Ontology (GO) analysis, we focused on dual‐specificity phosphatase 8 (DUSP8) from the predicted miR‐21‐5p targets. Luciferase reporter assays confirmed that miR‐21‐5p bound directly to DUSP8. MiR‐21‐5p upregulation in vitro downregulated DUSP8 expression. Importantly, intracerebroventricularly injecting antagomir for miR‐21‐5p (A‐miR‐21‐5p), which was used to inhibit miR‐21‐5p in aged ICH rats, significantly reduced the neurological defects, repaired cognitive impairment, alleviated blood–brain barrier (BBB) permeability, inhibited neuronal apoptosis posthaemorrhage and accelerated haematoma absorption. In addition, serum miR‐21‐5p levels were notably elevated in patients relative to healthy individuals and were correlated with National Institutes of Health Stroke Scale (NIHSS) scores and clinical outcomes. In summary, A‐miR‐21‐5p increased HO‐1 expression in cerebral haematomas, thus eliciting the DUSP8‐modulated perifocal neuroprotective effect of haemin. MiR‐21‐5p with haemin therapy may be a potential therapy post‐ICH. 相似文献
983.
Xiu Xiao Xiangqian Zhang Siyuan Wang Han Ouyang Pengfei Chen Liguo Song Haichao Yuan Yulong Ji Peihong Wang Zhou Li Minyi Xu Zhong Lin Wang 《Liver Transplantation》2019,9(40)
Vibration in mechanical equipment can serve as a sustainable energy source to power sensors and devices if it can be effectively collected. In this work, a honeycomb structure inspired triboelectric nanogenerator (HSI‐TENG) consisting of two copper electrode layers with sponge bases and one honeycomb frame filled with polytetrafluoroethylene (PTFE) balls is proposed to harvest vibration energy. The application of a compact honeycomb structure increases the maximum power density of HSI‐TENG by 43.2% compared to the square grid structure and provides superior advantages in large‐scale manufacturing. More importantly, the nonspring‐assisted HSI‐TENG can generate electricity once the PTFE balls obtain sufficient kinetic energy to separate from the bottom electrode layer regardless of the vibration frequency and direction. This is fundamentally different from the spring‐assisted harvesters that can only work around their natural frequencies. The vibration model and working criteria of the HSI‐TENG are established. Furthermore, the HSI‐TENG is successfully used to serve as a self‐powered sensor to monitor engine conditions by analyzing the electrical output of the HSI‐TENG installed on a diesel engine. Therefore, the nonspring‐assisted HSI‐TENG provides a novel strategy for highly effective vibration energy harvesting and self‐powered machinery monitoring. 相似文献
984.
985.
Tai-Long Pan Shu-Yuan Hsu Pei-Wen Wang Ya-Ting Cheng Yu-Chen Chang Sudipta Saha Jiwei Hu Pin Ouyang 《Cell cycle (Georgetown, Tex.)》2015,14(8):1174-1187
Investigation of the mechanisms leading to aneuploidy and polyploidy is critical to cancer research. Previous studies have provided strong evidence of the importance of tetraploidization as an early step in tumorigenesis. In cancer cells, tetraploid cells may contribute to abnormal mitotic progression, which may be associated with cytokinesis failure. Tetraploidy leads to genomic instability due to centrosome and chromosome over-replication. Until now, the mechanism by which cells maintain tetraploid status has been unknown. Here, we identified a novel D box-containing protein, FLJ25439, which displays a dynamic expression profile during mitosis/cytokinesis with the midbody as the most prominent associated structure. To understand the function of FLJ25439, we established stable cell lines overexpressing FLJ25439. FLJ25439-overexpression cells grew slower and displayed a tetraploid DNA content in comparison with diploid parental cells. They also showed aberrant mitosis and dysregulated expression of p53, pRb and p21, suggesting a defect in cell cycle progression. To explore the molecular mechanisms responsible for FLJ25439-induced tetraploidization, we conducted a comparative analysis of the global protein expression patterns of wild type and overexpressors using proteomics and bioinformatics approaches. Protein category profiling indicated that FLJ25439 is involved in pathways related to anti-apoptosis, protein folding, the cell cycle, and cytoskeleton regulation. Specifically, genotoxic-stress- and ER stress-related chaperone proteins greatly contributed to the FLJ25439 overexpression phenotypes. The results of this study pave the way to our further understanding of the role of this novel cytokinesis-related protein in protecting cells from environmental stress and tetraploid formation. 相似文献
986.
Owing to unsuitable green space construction, abundant allergenic pollen plants are centralized in urban areas, producing allergenic pollen. A mass of airborne allergenic pollen could cause pollinosis to badly influence people's robustness. To provide scientific basis for reasonable green space construction, the research advances of allergenic plants were reviewed. Firstly, species composition, phenological characteristics and influential factors (which include unsuitable green land construction, urban heat island effect, traffic pollution, etc.) were summarized. Secondly, the strategies controlling allergenic pollen plants were proposed. Thirdly, some problems on allergenic plants worthy of more research, including allergenic mechanism and methodology, were also put forward. 相似文献
987.
Generation and antitumor effects of an engineered and energized fusion protein VL-LDP-AE composed of single-domain antibody and lidamycin
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Type IV collagenase plays a pivotal role in invasion, metastasis and angiogenesis of tumor. Single domain antibodies are attractive
as tumor-targeting vehicle because of their much smaller size compared with antibody molecules produced by conventional methods.
Lidamycin (LDM) is a potent enediyne-containing antitumor antibiotic. In this study an engineered and energized fusion protein
VL-LDP-AE composed of lidamycin and VL domain of mAb 3G11 directed against type IV collagenase was prepared using a novel
two-step method. First a VL-LDP fusion protein was constructed by DNA recombination. Secondly VL-LDP-AE was obtained by molecular
reconstitution. In MTT assay, VL-LDP-AE showed potent cytotoxicity to HT-1080 cells and KB cells with IC
50 values of 8.55×10−12 and 1.70×10−11 mol/L, respectively. VL-LDP-AE showed antiangiogenic activity in chick chrorioallantoic membrane (CAM) assay and tube formation
assay. In in vivo experiments, VL-LDP-AE was proved to be more effective than free LDM against the growth of subcutaneously transplanted hepatoma
22 in mice. Drugs were given intravenously on day 3 and 10 after tumor transplantation. Compared in terms of maximal tolerated
doses, VL-LDP-AE at 0.25 mg/kg suppressed the tumor growth by 89.5%, LDM at 0.05 mg/kg by 69.9%, and mitomycin at 1 mg/kg
by 35%. Having a molecular weight of 25.2 kDa, VL-LDP-AE was much smaller than other reported antibody-based drugs. The results
suggested that VL-LDP-AE would be a promising candidate for tumor targeting therapy. And the 2-step approach could serve as
a new technology platform for making a series of highly potent engineered antibody-based drugs for a variety of cancers. 相似文献
988.
Mendes PM Christman KL Parthasarathy P Schopf E Ouyang J Yang Y Preece JA Maynard HD Chen Y Stoddart JF 《Bioconjugate chemistry》2007,18(6):1919-1923
The rational design of surfaces for immobilization of proteins is essential to a variety of biological and medical applications ranging from molecular diagnostics to advanced platforms for fundamental studies of molecular and cell biology. We have developed an advanced electrochemically based approach for site-selective and reaction-controlled immobilization of proteins on surfaces. When a molecular monolayer of 4-nitrothiophenol on gold electrode surfaces is reduced electrochemically in a selective fashion at its nitro groups, to afford amino groups by potentiometric scans, the amine can be employed to orchestrate the immobilization of proteins to the surface. This protein immobilization strategy could allow one to fabricate intricate protein structures on surfaces for addressing fundamental and applied problems in biology and medicine. 相似文献
989.
990.
Huo X Liu Y Wang X Ouyang P Niu Z Shi Y Qiu B 《Protein expression and purification》2007,54(2):234-239
Bovine follicle-stimulating hormone (bFSH) is a pituitary gonadotropin composed of two non-covalently associated polypeptide subunits, which must be glycosylated, folded, and assembled as a heterodimer to be biologically active. Low-level expression of the recombinant bFSH is the factor that limits its usefulness as a superovulation treatment for cows. To increase the production of recombinant bFSH, human protein disulfide isomerase (hPDI) was expressed simultaneously in engineered Pichia strains. The secretion characteristics of bFSH with or without hPDI were examined. The co-expression of bFSH and hPDI is increased to 1.56 mg/l of heterodimer in the culture medium, which is 6-fold higher when compared with the control strain carrying the bFSH gene only. These results may be generally applicable to increase the expression of other glycoprotein hormones in yeast. 相似文献