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131.
Cuong DV Warda M Kim N Park WS Ko JH Kim E Han J 《American journal of physiology. Heart and circulatory physiology》2007,293(3):H1457-H1465
In this study, dynamic changes in nitric oxide (NO) and mitochondrial superoxide (O(2)(*-)) were examined during anoxic preconditioning (AP) in rat heart model. AP and anoxia-reoxygenation (A/R) were performed on isolated hearts and single cardiomyocytes. The cellular insult in the form of infarct size and DNA damage were localized and correlated with NO synthases (endothelial and inducible) expression levels. The results showed that endocardium was the most affected region in AP groups, whereas the larger area of infarct was confined to mid- and epicardium in the A/R group. Interestingly, a high-level expression of immunofluorescent NO synthases was restricted to viable areas in the AP. In contrast to the gradual increase in O(2)(*-) level that occurred in the AP group, a sudden massive increase in its level was demonstrated at the onset of reoxygenation in the A/R group. The observed increase in NO production during reoxygenation in the AP group was attenuated by inducible NO synthase inhibitor. The study revealed, on a real-time basis, the role played by preconditioning for modulating NO and O(2)(*-) levels on behalf of cell survival. The results afford a better understanding of cardiac-adapting mechanism during AP and the role of inducible NO synthase in this important phenomenon. 相似文献
132.
The design and synthesis of new fluoroquinolone antibacterial agents having substituted piperidine rings at the C-7 position are described. Most of the new compounds demonstrated high in vitro antibacterial activity. Several of them exhibited significant activities against gram-positive organisms, which were more potent than those of gemifloxacin, Linezolid, and vancomycin. 相似文献
133.
Iron is essential for the normal functioning of cells but since it is also capable of generating toxic reactive oxygen species,
the metabolism of iron is tightly regulated. The present article advances the view that astrocytes are largely responsible
for distributing iron in the brain. Capillary endothelial cells are separated from the neuropil by the endfeet of astrocytes,
so astrocytes are ideally positioned to regulate the transport of iron to other brain cells and to protect them if iron breaches
the blood-brain barrier. Astrocytes do not appear to have a high metabolic requirement for iron yet they possess transporters
for transferrin, haemin and non-transferrin-bound iron. They store iron efficiently in ferritin and can export iron by a mechanism
that involves ferroportin and ceruloplasmin. Since astrocytes are a common site of abnormal iron accumulation in ageing and
neurodegenerative disorders, they may represent a new therapeutic target for the treatment of iron-mediated oxidative stress. 相似文献
134.
Background
Mucolipidosis Type IV is currently characterized as a lysosomal storage disorder with defects that include corneal clouding, achlorhydria and psychomotor retardation. MCOLN1, the gene responsible for this disease, encodes the protein mucolipin-1 that belongs to the "Transient Receptor Potential" family of proteins and has been shown to function as a non-selective cation channel whose activity is modulated by pH. Two cell biological defects that have been described in MLIV fibroblasts are a hyperacidification of lysosomes and a delay in the exit of lipids from lysosomes. 相似文献135.
136.
Whole genome analysis of Vietnamese G2P[4] rotavirus strains possessing the NSP2 gene sharing an ancestral sequence with Chinese sheep and goat rotavirus strains 下载免费PDF全文
Loan Phuong Do Toyoko Nakagomi Punita Gauchan Miho Kaneko Chantal Agbemabiese Anh Duc Dang Osamu Nakagomi 《Microbiology and immunology》2015,59(10):605-613
Because imminent introduction into Vietnam of a vaccine against Rotavirus A is anticipated, baseline information on the whole genome of representative strains is needed to understand changes in circulating strains that may occur after vaccine introduction. In this study, the whole genomes of two G2P[4] strains detected in Nha Trang, Vietnam in 2008 were sequenced, this being the last period during which virtually no rotavirus vaccine was used in this country. The two strains were found to be > 99.9% identical in sequence and had a typical DS‐1 like G2‐P[4]‐I2‐R2‐C2‐M2‐A2‐N2‐T2‐E2‐H2 genotype constellation. Analysis of the Vietnamese strains with > 184 G2P[4] strains retrieved from GenBank/EMBL/DDBJ DNA databases placed the Vietnamese strains in one of the lineages commonly found among contemporary strains, with the exception of the NSP2 and NSP4 genes. The NSP2 genes were found to belong to a previously undescribed lineage that diverged from Chinese sheep and goat rotavirus strains, including a Chinese rotavirus vaccine strain LLR with 95% nucleotide identity; the time of their most recent common ancestor was 1975. The NSP4 genes were found to belong, together with Thai and USA strains, to an emergent lineage (VIII), adding further diversity to ever diversifying NSP4 lineages. Thus, there is a need to enhance surveillance of locally‐circulating strains from both children and animals at the whole genome level to address the effect of rotavirus vaccines on changing strain distribution. 相似文献
137.
Kangmin He Xiaohua Yan Nan Li Song Dang Li Xu Bing Zhao Zijian Li Zhizhen Lv Xiaohong Fang Youyi Zhang Ye-Guang Chen 《Cell research》2015,25(6):738-752
Endocytosis and intracellular sorting of transforming growth factor-β (TGF-β) receptors play an important regulatory role in TGF-β signaling. Two major endocytic pathways, clathrin- and caveolae-mediated endocytosis, have been reported to independently mediate the internalization of TGF-β receptors. In this study, we demonstrate that the clathrin- and caveolae-mediated endocytic pathways can converge during TGF-β receptor endocytic trafficking. By tracking the intracellular dynamics of fluorescently-labeled TGF-β type I receptor (TβRI), we found that after mediating TβRI internalization, certain clathrin-coated vesicles and caveolar vesicles are fused underneath the plasma membrane, forming a novel type of caveolin-1 and clathrin double-positive vesicles. Under the regulation of Rab5, the fused vesicles are targeted to early endosomes and thus deliver the internalized TβRI to the caveolin-1 and EEA1 double-positive early endosomes (caveolin-1-positive early endosomes). We further showed that the caveolin-1-positive early endosomes are positive for Smad3/SARA, Rab11 and Smad7/Smurf2, and may act as a multifunctional device for TGF-β signaling and TGF-β receptor recycling and degradation. Therefore, these findings uncover a novel scenario of endocytosis, the direct fusion of clathrin-coated and caveolae vesicles during TGF-β receptor endocytic trafficking, which leads to the formation of the multifunctional sorting device, caveolin-1-positive early endosomes, for TGF-β receptors. 相似文献
138.
Amanda C. Crisostomo Loan Dang Jyothi L. Digambaranath Andrea C. Klaver David A. Loeffler Jeremiah J. Payne Lynnae M. Smith Adam L. Yokom John M. Finke 《Analytical biochemistry》2015
Surface plasmon resonance was used to investigate the kinetics, affinity, and specificity of binding between anti-Aβ (beta-amyloid) IgG antibodies and oligomeric Aβ. Two factors were needed to accurately characterize the IgG binding kinetics. First, a bivalent model was necessary to properly fit the kinetic association and dissociation sensograms. Second, a high concentration of IgG was necessary to overcome a significant mass transport limitation that existed regardless of oligomer density on the sensor surface. Using high IgG concentrations and bivalent fits, consistent kinetic parameters were found at varying sensor surface ligand densities. A comparison of binding specificity, affinity, and kinetic flux between monoclonal and natural human anti-Aβ IgG antibodies revealed the following findings. First, monoclonal antibodies 6E10 and 4G8 single-site binding affinity is similar between Aβ oligomers and monomers. Second, natural human anti-Aβ IgG binding readily binds Aβ oligomers but does not bind monomers. Third, natural human anti-Aβ IgG binds Aβ oligomers with a higher affinity and kinetic flux than 6E10 and 4G8. Both the current analytical methodology and antibody binding profiles are important for advances in antibody drug development and kinetic biomarker applications for Alzheimer’s disease. 相似文献
139.
Molluscs, comprising one of the most successful phyla, lack clear evidence of adaptive immunity and yet thrive in the oceans, which are rich in viruses. There are thought to be nearly 120,000 species of Mollusca, most living in marine habitats. Despite the extraordinary abundance of viruses in oceans, molluscs often have very long life spans (10 to 100 years). Thus, their innate immunity must be highly effective at countering viral infections. Antiviral compounds are a crucial component of molluscan defenses against viruses and have diverse mechanisms of action against a wide variety of viruses, including many that are human pathogens. Antiviral compounds found in abalone, oyster, mussels, and other cultured molluscs are available in large supply, providing good opportunities for future research and development. However, most members of the phylum Mollusca have not been examined for the presence of antiviral compounds. The enormous diversity and adaptations of molluscs imply a potential source of novel antiviral compounds for future drug discovery. 相似文献
140.
Yu Zhang Rong-quan He Yi-wu Dang Xiu-ling Zhang Xiao Wang Su-ning Huang Wen-ting Huang Meng-tong Jiang Xiao-ning Gan You Xie Ping Li Dian-zhong Luo Gang Chen Ting-qing Gan 《Cancer cell international》2015,16(1):89