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21.
以紫外光谱、荧光光谱、粘度法和凝胶电泳方法研究了全反式维甲酸合钇(Ⅲ)配合物与DNA的作用。结果表明,该配合物能在生理条件下比配体和金属离子更有效地切割质粒DNA,体系离子强度和pH值的变化对配合物的切割活性有较大影响,自由基捕捉剂的加入不影响配合物的切割活性。该配合物对DNA的切割可能通过水解机理进行。该配合物可使DNA的粘度增加,使EB-DNA体系的荧光强度和DNA溶液的紫外吸收强度降低。据此推断,该配合物主要以嵌入方式与DNA作用。 相似文献
22.
In weakly acidic buffer medium, the interaction of amikacin with calf thymus DNA, yeast RNA and denatured DNA has been investigated by using resonance Rayleigh scattering (RRS) technique. The result shows that calf thymus DNA is capable of enhancing the RRS intensity of the amikacin, while yeast RNA and denatured DNA have very little enhancement effect. Based on the characteristics, a sensitive assay for detecting double-stranded DNA in the presence of denatured DNA and yeast RNA has been developed. The enhancement of the RRS signal is directly proportional to the concentration of double-stranded DNA in the range 0.02-12.0 μg ml−1 for calf thymus DNA and its detection limit (3σ) is 2.5 ng ml−1. The method shows a wide linear range and high sensitivity, and almost no interference can be observed from RNA, denatured DNA, amino acid and most of the metal ions. The trace amounts of nucleic acid in synthetic samples and practical samples are determined with satisfactory results. Therefore, the proposed method is promising for as an effect means for recognition in vivo and determination in situ of double-stranded DNA. 相似文献
23.
抗癌药物的电化学研究(Ⅱ)道诺霉素在DNA修饰石墨粉末微电极上的电化学行为及分析应用 总被引:8,自引:0,他引:8
研究了道诺霉素 ( DNM)在石墨粉末微电极和 DNA修饰石墨粉末微电极上的电化学行为 ,并分析了产生差别的原因。在此基础上 ,提出了测定微量 DNM的方法 ,DNM浓度在 1 .0× 1 0 - 7~ 1 .0× 1 0 - 5mol/L之间其微分脉冲伏安 ( DPV)峰电流与浓度有良好的线性关系 ,检出限为 5 .0× 1 0 - 8mol/L。采用标准加入法测定了模拟样品中的 DNM,回收率在 94%~ 1 0 8%之间 ,结果令人满意 相似文献
24.
Two kinds of thio-heterocyclic fused naphthalene carboxamides, 3a-b, 4a-b, were designed, synthesized and quantitatively evaluated as efficient antitumor and DNA photocleaving agents. Compound 3a or 3b, having the thiophene ring, intercalated into DNA more strongly than compound 4a or 4b, having the thioxanthene ring. Compound 4a or 4b, photocleaved DNA more efficiently than 3a or 3b via superoxide anion. Compound 4a was the strongest inhibitor for P388 (murine leukemia cell), while 3a was the most cytotoxic one against A549 (human lung cancer cell). Each new compound showed stronger DNA photocleaving activity than corresponding naphthalimide. 相似文献
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Summary Intercalators are molecules capable of sliding between DNA base pairs without breaking up the hydrogen bonds between the DNA bases. On the basis of molecular mechanics calculations structural, models of B-DNA tetranucleotide intercalation complexes of some cytostatic active 9-aminoacridines and of a [d, e]-anellated isoquinoline derivative are presented. The drug complexes are stabilized by energetically favouredvan der Waals interactions and by selective hydrogen bonds between the side chains of the drugs and the DNA bases. Semiempirical quantum chemistry calculations revealed that the chromophoric system of the intercalators is able to form ,-charge-transfer interactions with the purine bases of the base paired deoxytetranucleotides. The theoretical findings are of interest for a more specific drug design of cytostatically active agents.
Molecular Modeling von Interkalationskomplexen antitumoraktiver 9-Aminoacridine sowie eines [d, e]-anellierten Isochinolinderivates mit basengepaarten Desoxytetranukleotiden
Zusammenfassung Interkalatoren sind Moleküle, die in der Lage sind, sich zwischen DNA-Basenpaare einzulagern, ohne die Wasserstoffbrücken zwischen den DNA-Basen aufzubrechen. Auf der Basis von molekülmechanischen Rechnungen werden Tetranukleotid-Interkalationskomplexe von verschiedenen zytostatisch aktiven 9-Aminoacridinen und von einem [d, e]-anellierten Isochinolinderivat präsentiert. Die Komplexe werden durch energetisch günstigevan der Waals-Interaktionen sowie durch selektive Wasserstoffbrückenbindungen zwischen den Seitenketten der Wirkstoffe und den DNA-Basen stabilisiert. Semiempirische quantenchemische Rechnungen ergaben, daß der Chromophor der Interkalatoren in der Lage ist, ,-charge-transfer Wechselwirkungen mit den Purinbasen der basengepaarten Desoxytetranukleotide auszubilden. Die theoretischen Ergebnisse sind für ein spezifischeres Wirkstoffdesign zytostatisch aktiver Verbindungen von Interesse.相似文献
28.
Liquid chromatography plays a central role in process-scale manufacturing of therapeutic plasmid DNA (pDNA) for gene therapy and DNA vaccination. Apart from its use as a preparative purification step, it is also very useful as an analytical tool to monitor and control pDNA quality during processing and in final formulations. This paper gives an overview of the use of pDNA chromatography. The specificity of pDNA purification and the consequent limitations to the performance of chromatography are described. Strategies currently used to overcome those limitations, as well as other possible solutions are presented. Applications of the different types of chromatography to the purification of therapeutic pDNA are reviewed, and the main advantages and disadvantages behind each technique highlighted. 相似文献
29.
微流控芯片技术在生命科学研究中的应用 总被引:4,自引:0,他引:4
微流控芯片最初起源于分析化学领域,是一种采用精细加工技术,在数平方厘米的基片,制作出微通道网络结构及其它功能单元,以实现集微量样品制备、进样、反应、分离及检测于一体的快速、高效、低耗的微型分析实验装置.随着微电子及微机械制作技术的不断进步,近年来微流控芯片技术发展迅猛,并开始在化学、生命科学及医学器件等领域发挥重要作用.本文首先简单介绍了微流控芯片制作材料和工艺,然后主要阐述了其在蛋白质分离、免疫分析、DNA分析和测序、细胞培养及检测等方面的应用进展. 相似文献
30.
The sequence-specific recognitions between DNA and proteins are playing important roles in many biological functions. The double-stranded DNA microarrays (dsDNA microarrays) can be used to study the sequence-specific recognitions between DNAs and proteins in highly parallel way. In this paper, two different elongation processes in forming dsDNA from the immobilized oligonucleotides have been compared in order to optimize the fabrication of dsDNA microarrays: (1) elongation from the hairpins formed by the self-hybridized oligonucleatides spotted on a glass; (2) elongation from the complementary primers hybridized on the spotted oligonucleatides. The results suggested that the dsDNA probes density produced by the hybridized-primer extension was about four times lower than those by the self-hybridized hairpins. Meanwhile, in order to reduce the cost of dsDNA microarrays, we have replaced the Klenow DNA polymerase with Taq DNA polymerase, and optimized the reaction conditions of on-chip elongation. Our experiements showed that the elongation temperature of 50 °C and the Mg2+ concentration of 2.5 mM are the optimized conditions in elongation with Taq DNA polymerase. A dsDNA microarray has been successfully constructed with the above method to detect NF-kB protein. 相似文献