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71.
The complement fixation test and the immunofluorescence test have demonstrated that the L-forms of mycobacteria retain their species-specific and genus-specific determinants and possess serological activity. The L-variants obtained by different methods differ in size, depending on the degree of the destruction of their cell wall. Specific antisera to the L-forms of mycobacteria, suitable for use in the indirect immunofluorescence test, have been obtained. These antisera are highly specific and permit not only the rapid detection, but also identification of the L-forms. 相似文献
72.
L N Narodetskaia Z N Kovalenko 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1978,(9):74-76
The blood level of IgA, IgG Igm, and protein in male donors was studied in connection with the duration of the donor's activity. The content of the main blood immunoglobulin classes and proteins depended significantly on the duration of the donor's activity. Therefore it is not recommended to use donors as control group in determining the immunoglobulin level in the blood. 相似文献
73.
N Ia Kovalenko D D Matsievski? 《Biulleten' eksperimental'no? biologii i meditsiny》1992,114(8):128-130
Using the method of contact luminescent biomicroscopy of the liver and intestine coupled with the measurement of systemic blood pressure by micromanometer and ultrasonic registration of blood flow velocity in portal vein and hepatic artery it has been established that in rats with acute decompensatory hemorrhage fragments of ACTH (1-24) and (4-10) improve the state of portal macro- and microcirculation and increase the life span 2-3-fold. ACTH does not influence the dynamics of acute compensatory hemorrhage and the development of the posthemorrhagic microcirculatory disturbances (local microstases, microthromboses, erythrocyte aggregation). 相似文献
74.
A method used to prepare the inoculum (a strain of Bacillus mesentericus, a producer of a complex of hydrolytic enzymes) has been studied for its effect on the activity of proteinases and amylases under submerged cultivation in fermenters. Optimal conditions for the culture storage and inoculum cultivation are developed to obtain standard enzymic preparations. 相似文献
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Separation of optical isomers obtainable from trans‐norborn‐5‐ene‐2,3‐dicarboxylic acid methyl and tert‐butyl monoesters was performed by crystallization of the respective salts prepared with (R)‐ and (S)‐1‐phenylethylamine. Starting from racemic endo‐monomethyl ester of trans‐norborn‐5‐ene‐2,3‐dicarboxylic acid, prepared by partial hydrolysis of the cyclopentadiene‐dimethyl fumarate adduct, the corresponding (2R,3R)‐endo‐monoester was isolated in 97% enantiomeric excess (ee) yield after seven repeated crystallizations from tetrachloromethane. Starting from exo‐mono‐tert‐butyl ester of the same acid, prepared by alcoholysis of the cyclopentadiene‐maleic anhydride adduct followed by isomerization, (2R,3R)‐exo‐monoester was isolated in >98% ee yield after four repeated crystallizations from ethanol. Crystallization of the acids from the mother liquor containing (S)‐1‐phenylethylamine yielded products with inverse stereochemical configuration. Chirality 27:151–155, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
80.
Mariia Yu. Rybak Oksana P. Kovalenko Michael A. Tukalo 《Journal of molecular biology》2018,430(17):2670-2676
Aminoacyl-tRNA-synthetases are crucial enzymes for initiation step of translation. Possessing editing activity, they protect living cells from misincorporation of non-cognate and non-proteinogenic amino acids into proteins. Tyrosyl-tRNA synthetase (TyrRS) does not have such editing properties, but it shares weak stereospecificity in recognition of d-/l-tyrosine (Tyr). Nevertheless, an additional enzyme, d-aminoacyl-tRNA-deacylase (DTD), exists to overcome these deficiencies. The precise catalytic role of hydroxyl groups of the tRNATyr A76 in the catalysis by TyrRS and DTD remained unknown. To address this issue, [32P]-labeled tRNATyr substrates have been tested in aminoacylation and deacylation assays. TyrRS demonstrates similar activity in charging the 2′ and 3′-OH groups of A76 with l-Tyr. This synthetase can effectively use both OH groups as primary sites for aminoacylation with l-Tyr, but demonstrates severe preference toward 2′-OH, in charging with d-Tyr. In both cases, the catalysis is not substrate-assisted: neither the 2′-OH nor the 3′-OH group assists catalysis. In contrast, DTD catalyzes deacylation of d-Tyr-tRNATyr specifically from the 3′-OH group, while the 2′-OH assists in this hydrolysis. 相似文献