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841.
842.
Amar Abhishek Nasreen Ghazi Ansari Satya Narayan Shankhwar Amita Jain Vishwajeet Singh 《Bioinformation》2014,10(12):716-720
The induced toxicity of three pesticides (alpha-Hexachlorocyclohexane: α-HCH; Parathion methyl:PM; Carbofuran: CN) in single
and four possible combination on human keratinocyte cell line have been investigated. There was no significant change in toxicity
(cyto and genotoxicity) on cell line exposed by individual pesticides except α-HCH. But, a synergistic effect was observed when we
tested mixture of pesticides. The intracellular ROS and cytotoxicity assay revealed maximum reduction in cell viability (60%) was
found in tri mixture of pesticides. All the possible combination of these pesticides demonstrated genotoxic activity in terms of olive
tail moment and % tail DNA on cell line at low concentration. The order of toxicity was ranked as α-HCH+PM+CN>α-
HCH+CN>PM+CN>α-HCH+PM. Our results call for more research to be undertaken in order to understand the mechanisms
behind the synergy observed and quantify the extent of its environmental impacts. 相似文献
843.
844.
Gregor P Jose Subhankar Santra Swadhin K Mandal Tapas K Sengupta 《Journal of nanobiotechnology》2011,9(1):9
The DNA degradation potential and anti-cancer activities of copper nanoparticles of 4-5 nm size are reported. A dose dependent
degradation of isolated DNA molecules by copper nanoparticles through generation of singlet oxygen was observed. Singlet oxygen
scavengers such as sodium azide and Tris [hydroxyl methyl] amino methane were able to prevent the DNA degradation action of
copper nanoparticles confirming the involvement of activated oxygen species in the degradation process. Additionally, it was
observed that the copper nanoparticles are able to exert cytotoxic effect towards U937 and Hela cells of human histiocytic
lymphoma and human cervical cancer origins, respectively by inducing apoptosis. The growth characteristics of U937 and Hela
cells were studied applying various concentrations of the copper nanoparticles. 相似文献
845.
Although pathogenic bacteria penetrate colonic cells causing infection, the role of its surface molecules serving as key Toll-like receptor (TLR) ligands and triggering response remains unexplored. We show that TLR2-ligand porin up-regulated TLR4 on HT-29 cells, which the TLR4-ligand LPS could not. TLR1 that co-express with TLR2 got stimulated with TLR4. Besides the two TLRs, MD-2 was expressed revealing that the TLR4 co-receptor is not exclusive for LPS signaling. SARM-1 that mostly down-regulates TLR-signaling, demonstrated central role in signaling by engaging IRF-3 and NF-κB for cell activity. Porin induced type 1 chemokines particularly MCP-3, while porin-stimulated HT-29 culture supernatant displayed PBMC migration, collectively suggesting that the chemokines influence colon and immune cell cross-talk. In TLR2 down-regulated HT-29 cells, we found TLR1 and TLR4 as substitute TLRs to identify porin and orchestrate signaling. Thus, TLR replacement for PAMP recognition demonstrates specificity of ligand·TLR association can compromise and is a necessary alternative for successful execution of immune responses. 相似文献
846.
847.
Satya K. Kota 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(12):1280-1283
X inactivation is the process that brings about the dosage equivalence of X‐linked genes in females to that of males. This complex process initiated at a very early stage of female embryonic development is orchestrated by long non‐coding RNAs transcribed in both sense and antisense orientation. Recent studies present contradicting evidence for the role of small RNAs and RNase III enzyme Dicer in the X inactivation process. In this review, I discuss these results in the overall perspective of X inactivation and gene silencing. 相似文献
848.
849.
Despite the growing awareness of the ecological importance of epibiont-host associations, detailed inventories for planktonic hosts are rare. Here, we provide an updated checklist of the peritrich and suctorian epibiont ciliates (Ciliophora) on the cladocerans (Crustacea: Cladocera). Thirty-nine species of peritrich ciliates (of which 34 are assigned to species) and three species of suctorian ciliates are found to be epibionts on the Cladocera. Fifty-eight cladoceran taxa are known to be hosts of the ciliate epibionts, 33 of these hosts (57%) are planktonic. Seven taxa were determined to the level of genus. Complete species designations were geographically biased (38 of 51 species) towards European sites, suggesting poor taxonomic knowledge beyond Europe. Also, the recently discovered continental endemism of cladoceran hosts could indicate that associated ciliates are more diverse than previously appreciated. 相似文献
850.
Previous studies have shown that the breast cancer suppressor BRCA1 stimulates antioxidant gene expression and protects cells against oxidative stress. To further examine this important function, we tested whether BRCA1 could modulate intracellular levels of reactive oxygen species (ROS). Wild-type BRCA1 (but not a cancer-associated mutant) significantly reduced ROS levels, determined by DCF fluorescence assays by flow cytometry and confocal microscopy. The BRCA1 and REF1 pathways for reduction of ROS levels appear to exhibit cross-talk. BRCA1 also reduced the levels of protein nitration and H2O2-induced oxidative damage to DNA. Thus, BRCA1 may protect cellular macromolecules by reducing intracellular ROS levels. 相似文献