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Kadiiska MB Gladen BC Baird DD Germolec D Graham LB Parker CE Nyska A Wachsman JT Ames BN Basu S Brot N Fitzgerald GA Floyd RA George M Heinecke JW Hatch GE Hensley K Lawson JA Marnett LJ Morrow JD Murray DM Plastaras J Roberts LJ Rokach J Shigenaga MK Sohal RS Sun J Tice RR Van Thiel DH Wellner D Walter PB Tomer KB Mason RP Barrett JC 《Free radical biology & medicine》2005,38(6):698-710
Oxidation products of lipids, proteins, and DNA in the blood, plasma, and urine of rats were measured as part of a comprehensive, multilaboratory validation study searching for noninvasive biomarkers of oxidative stress. This article is the second report of the nationwide Biomarkers of Oxidative Stress Study using acute CCl4 poisoning as a rodent model for oxidative stress. The time-dependent (2, 7, and 16 h) and dose-dependent (120 and 1200 mg/kg i.p.) effects of CCl4 on concentrations of lipid hydroperoxides, TBARS, malondialdehyde (MDA), isoprostanes, protein carbonyls, methionine sulfoxidation, tyrosine products, 8-hydroxy-2'-deoxyguanosine (8-OHdG), leukocyte DNA-MDA adducts, and DNA-strand breaks were investigated to determine whether the oxidative effects of CCl4 would result in increased generation of these oxidation products. Plasma concentrations of MDA and isoprostanes (both measured by GC-MS) and urinary concentrations of isoprostanes (measured with an immunoassay or LC/MS/MS) were increased in both low-dose and high-dose CCl4-treated rats at more than one time point. The other urinary markers (MDA and 8-OHdG) showed significant elevations with treatment under three of the four conditions tested. It is concluded that measurements of MDA and isoprostanes in plasma and urine as well as 8-OHdG in urine are potential candidates for general biomarkers of oxidative stress. All other products were not changed by CCl4 or showed fewer significant effects. 相似文献
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Assembly of the HIV-1 virus involves, in part, strong interactions between the capsid (CA) domains of the Gag polyprotein. During maturation, the core of HIV-1 virions undergoes profound morphological changes due primarily to proteolysis of the CA domain from other Gag domains which may allow for more efficient disassembly of the viral core in the early stages of infection. The host protein cyclophilin A (CypA), a cis-trans prolyl isomerase, in some way seems to assist in this assembly/disassembly process. Using an unproteolyzed construct of CA, we show that binding of CypA induces a large-scale conformational change in CA that is independent of its cis-trans prolyl isomerase activity. This change appears to be mediated by Cys-198 of CA since mutation to Ala renders CypA unable to induce this change and alters the kinetics and stability of protein cores that may ultimately result in inefficient disassembly of viral cores. Alternately, mutation of the second CA Cys (C218A) allows for CypA-induced conformational changes but alters the kinetics and morphology of the protein cores that may ultimately result in inefficient assembly of viral cores. These studies show the importance of the CA Cys residues in mediating the contacts needed for viral assembly and disassembly. 相似文献
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Judith?E?StengerEmail author Hong?Xu Carol?Haynes Elizabeth?R?Hauser Margaret?Pericak-Vance Pascal?J?Goldschmidt-Clermont Jeffery?M?Vance 《BMC bioinformatics》2005,6(1):95
Background
To facilitate efficient selection and the prioritization of candidate complex disease susceptibility genes for association analysis, increasingly comprehensive annotation tools are essential to integrate, visualize and analyze vast quantities of disparate data generated by genomic screens, public human genome sequence annotation and ancillary biological databases. We have developed a plug-in package for Ensembl called "Statistical Viewer" that facilitates the analysis of genomic features and annotation in the regions of interest defined by linkage analysis. 相似文献999.
Carol?E?DonaldEmail author Fizza?Qureshi Malcolm?J?Burns Marcia?J?Holden Joseph?R?BlasicJr Alison?J?Woolford 《BMC biotechnology》2005,5(1):15
Background
The wide variety of real-time amplification platforms currently available has determined that standardisation of DNA measurements is a fundamental aspect involved in the comparability of results. 相似文献1000.
Mason CA Kirby RS Sever LE Langlois PH 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(10):690-692
Researchers and other public health professionals continue to debate the use of prevalence versus incidence as the preferred term to represent the frequency of birth defects. This paper addresses this question by noting that incidence--the number of new cases of a disorder in a given at-risk population during a specified time period--cannot be reliably estimated with existing data. Consequently, it is not appropriate to use the term "incidence" in reporting the frequency of birth defects, and the term prevalence is recommended. The basis for this recommendation, and issues involved in calculating both measures, are discussed. 相似文献