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排序方式: 共有506条查询结果,搜索用时 15 毫秒
1.
采用表面光滑玻璃珠作为载体材料,用1:40的腹泻性大肠杆菌诊断血清进行包被。可制成免疫珠。这种免疫珠能与腹泻性大肠杆菌发生特异性结合。经乳糖蛋白胨培养液培养,然后根据其产酸产气进行判断。能在18h内完成腹泻性大肠杆菌的检测。其灵敏度为样液中含有腹泻性大肠杆菌数必须大于10CFu/mL.该法简单、快速、易操作、灵敏度高。 相似文献
2.
Yu. Dryagin N. Scalyga T. Geist 《International Journal of Infrared and Millimeter Waves》1996,17(7):1199-1204
The construction of a notch-filter for 140 GHz with very low passband insertion loss is described. It is based on a single-mode rectangular waveguide and cylindrical cavities matched to it. The typical transmission characteristic is also presented. 相似文献
3.
文章提出了工程项目施工的投资状态函数、进度状态函数、质量状态函数和环境状态函数,并以状态函数为基础,建立了项目施工状态诊断模型。文章给出各层次中的状态函数,理出了施工状态量化诊断的思路,对各层次中状态诊断函数的描述作了探索。 相似文献
4.
5.
一个多元校正的稳健诊断新方法 总被引:1,自引:0,他引:1
提出一种新的稳健诊断方法,与最小二乘估计结合进行混合物光谱中非线性点的诊断。文中探讨了该方法的性能,用计算机数字模拟及实际多组分光谱体系夺其进行检验,展示了此诊断方法在分析化学计量学中实际应用的可行性。 相似文献
6.
神经网络多参数诊断法 总被引:3,自引:0,他引:3
讨论了机械故障诊断中采用多参数诊断法的必要性,阐述了神经网络理论用于多参数诊断的理论依据,归纳了神经网络多参数诊断法的实施步骤,并以滚动轴承故障诊断为例,对该方法进行了实验验证,证明了该方法的实用性。 相似文献
7.
In the study, a series of C_(30)-C_(32) lanostane homologs have been identified from Eogene source rocks and crude oils of Biyang depression in Henan Province, China. Based upon the geochemical investigations and simulating experiments, the idea that the generation of lanostane may mainly be related to the specific original organic inputs and low maturity has been proposed. 相似文献
8.
Basinska T 《Macromolecular bioscience》2005,5(12):1145-1168
Functional hydrophilic microspheres (latex particles) have found various applications in life sciences and in medicine - particularly in latex diagnostic tests. This paper presents a comprehensive review of studies on latex particles with a hydrophilic interfacial layer composed of various hydrophilic polymers with reactive groups at the ends of macromolecules or at each monomeric unit along the chain. Typical examples of these hydrophilic polymers are poly(2-hydroxyethyl methyl methacrylate), poly(acrylic acid), poly(N,N-dimethylacrylamide), polysaccharides, poly(ethylene oxide) and polyglycidol. Hydrophilic microspheres with different morphologies (uniform or core-shell, see Figure) have been synthesized by emulsion and dispersion polymerizations. The chemical structure of polymers which constitute the interfacial layer of microspheres has been investigated using a variety of instrumental techniques (such as XPS, SSIMS and NMR) and analytical methods based on specific chemical reactions suitable for the determination of particular functional groups. Microspheres are exposed to contact with proteins in the majority of medical applications. This paper presents examples of studies on the attachment of these biomacromolecules to microspheres. The relation between the structure of the interfacial layer of microspheres and the ability of these particles for the covalent binding of proteins is discussed. Several examples of diagnostic tests, in which hydrophilic microspheres with adsorbed or covalently immobilized proteins were used as reagents, are presented. The paper also contains a short review of the application of magnetic hydrophilic particles for protein separation. Examples of hydrophilic latex particles used for hemoperfusion or heavy metal ion separation are presented. Hydrophilic microspheres with uniform or core-shell morphologies. 相似文献
9.
The principle of a novel latex diagnostic test for the determination of antibodies against Helicobacter pylori in blood sera is described. The test is based on the measurement of the electrophoretic mobility of the microspheres with immobilized H. pylori antigens. The electrophoretic mobility of these microspheres depends on the concentration of the antibodies against H. pylori in suspending medium. Particles with hydrophilic polyglycidol in the surface layer were used for the test. The microspheres were obtained by an emulsifier-free emulsion copolymerization of styrene and alpha-tert-butoxy-omega-vinylbenzyl-polyglycidol macromonomer (D(n) = 220 nm, diameter polydispersity factor D(w)//D(n) = 1.02). Activation of polyglycidol hydroxyl groups with cyanuric chloride allowed for covalent immobilization of H. pylori antigens. The fraction of H. pylori not specifically adsorbed onto the microspheres was negligible. Changes of the electrophoretic mobility of the microspheres with the surface concentration of the covalently immobilized H. pylori antigens Gamma = (1.6 +/- 0.3) . 10(-3) g m(-2) were suitable for the detection of the antibodies in the sera of patients with titer in the range (determined by the indirect ELISA test) from 1:500 to 1:32 000. 相似文献
10.
J. D. Theis S. Dasari J. A. Vrana P. J. Kurtin A. Dogan 《Journal of mass spectrometry : JMS》2013,48(10):i-i
Shotgun proteomics technology has matured in the research laboratories and is poised to enter clinical laboratories. However, the road to this transition is sprinkled with major technical unknowns such as long‐term stability of the platform, reproducibility of the technology and clinical utility over traditional antibody‐based platforms. Further, regulatory bodies that oversee the clinical laboratory operations are unfamiliar with this new technology. As a result, diagnostic laboratories have avoided using shotgun proteomics for routine diagnostics. In this perspectives article, we describe the clinical implementation of a shotgun proteomics assay for amyloid subtyping, with a special emphasis on standardizing the platform for better quality control and earning clinical acceptance. This assay is the first shotgun proteomics assay to receive regulatory approval for patient diagnosis. The blueprint of this assay can be utilized to develop novel proteomics assays for detecting numerous other disease pathologies. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献