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91.
S. A. Savchuk S. A. Appolonova O. M. Kogdas’ V. N. Unizhaev O. S. Gorina L. N. Rizvanova N. V. Samyshkina K. M. Shestakova 《Journal of Analytical Chemistry》2017,72(11):1193-1202
The appearance of a new APINAC compound (AKB-57, ACBL(N)-018, adamantan-1-yl-1-pentyl-1H-indazol-3-carboxylate) in the Russian market of psychoactive drugs led to the need in setting measures of state control over its turnover and in solving the problem of categorizing this compound as a potentially hazardous psychoactive substance. To establish these control measures, it was necessary to determine the appropriate chromatographic–mass spectrometric characteristics and to search for its metabolites for their subsequent automated detection. The structure of an APINAC molecule has significant similarity with the molecules of other synthetic cannabinoids. In this paper, primary information on the metabolism of APINAC in the body of rats is presented. A number of putative metabolites, which are the products of hydrolysis of the initial structure and additional monohydroxylation of these products, carbonylation and carboxylation of the lateral N-pentyl chain of indazole-containing metabolites, were detected in rat urine by liquid chromatography–mass spectrometry in the mode of measurement of exact masses and gas chromatography–mass spectrometry. It was found that the formation of glucuronides is characteristic for 1-adamantol and its monohydroxylated metabolite and for the indazole-containing product of hydrolysis of APINAC. The presented mass spectra and retention characteristics of the detected metabolites can help in the detection of these (or similar) compounds in human urine. 相似文献
92.
A series of 2,2‐dimethyl‐5‐(5′‐R‐hetarylidene)‐1,3‐dioxane‐4,6‐diones has been synthesized for examing a structure–activity relationship. Furyl and thienyl derivatives of Meldrum's acid possess neurotropic activity comprising both depriming and activating components. Comparison of acute toxicity of carbon, silicon and germanium analogues in the furan series of the compounds has demonstrated that the germanium derivative is 11.5 times less toxic than the carbon analogue and four times less toxic than the silicon derivative. 2,2‐Dimethyl‐5‐(5′‐triethylsilyl‐2′‐thenylidene)‐1,3‐dioxane‐4,6‐dione has moderate toxicity with the highest neurotropic and cytotoxic activity Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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94.
Integrating 31P DOSY NMR Spectroscopy and Molecular Mechanics as a Powerful Tool for Unraveling the Chemical Structures of Polyoxomolybdate‐Based Amphiphilic Nanohybrids in Aqueous Solution 下载免费PDF全文
Assoc. Prof. Pavletta Shestakova Dr. Gregory Absillis Dr. Francisco J. Martin‐Martinez Prof. Frank De Proft Prof. Rudolph Willem Prof. Tatjana N. Parac‐Vogt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(18):5258-5270
Novel organic–inorganic hybrids of various sizes were generated by reaction of 1,8‐octanediphosphonic acid (ODP) and (NH4)6Mo7O24 in aqueous solution. The formation of rodlike hybrids with variable numbers of covalently bound ODP and polyoxomolybdate (POM) units can be tuned as a function of increasing (NH4)6Mo7O24 concentration at fixed ODP concentration. The chemical structure of the ODP/POM hybrids was characterized by 1H, 31P, and 95Mo NMR spectroscopy. Heteronuclear 31P DOSY (diffusion‐ ordered NMR spectroscopy) and molecular mechanics (MM) calculations were applied to determine the size and shape of the nanosized hybrids generated at various ODP/POM ratios. For this purpose, the structures of ODP/POM hybrids with variable numbers of ODP and POM units were optimized by MM and then approximated as cylinder‐shaped objects by using a recently described mathematical algorithm. The thus‐obtained cylinder length and diameter were further used to calculate the expected diffusion coefficients of the ODP/POM hybrids. Comparison of the calculated and experimentally determined diffusion coefficients led to the most probable ODP/POM hybrid length for each sample composition. The 31P DOSY results show that the length of the hybrids increases with increasing POM concentration and reaches a maximum corresponding to an average of 8 ODP/7 POM units per chain at a sample composition of 20 mM ODP and 14 mM POM. With excess POM, above the latter concentration, the formation of shorter‐chain hybrids terminated by Mo7 clusters at one or both ends was evidenced on further increasing the POM concentration. The results demonstrate that the combination of 31P DOSY and MM, although virtually unexplored in POM chemistry, is a powerful innovative strategy for the detailed characterization of nanosized organic–inorganic POM‐based hybrids in solution. 相似文献
95.
Izolda Segal Alla Zablotskaya Edmunds Lukevics Mikhail Maiorov Dmitry Zablotsky Elmars Blums Irina Shestakova Ilona Domracheva 《应用有机金属化学》2008,22(2):82-88
New original water‐soluble magnetic nanoparticles based on natural components, magnetite–oleic acid–biologically active silyl modified alkanolamine, were synthesized. Physico‐chemical characterization, i.e. magnetic properties, concentration of magnetite, size of iron oxide core, of the nanoparticles synthesized and the corresponding magnetic fluids obtained, was carried out. Magnetic fluids were screened for in vitro cytotoxicity concerning human fibrosarcoma (HT‐1080), mouse hepatoma (MG‐22A) monolayer tumour cell lines and normal mouse fibroblasts (NIH 3T3). They possess low or moderate cytotoxic effects, are non‐toxic, exhibit high NO‐induction ability and strongly change tumour cell morphology. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
96.
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98.
D. Zaruma E. Lukevics L. Ignatovich I. Shestakova I. Domracheva V. Bridane E. Yashchenko J. Ashaks 《Chemistry of Heterocyclic Compounds》2012,47(12):1539-1543
A series of 8-quinolinethiolates, and 3-methyl-, 4-methyl-, 5-methyl-, 6-methyl-, 7-methyl-, and 6-methoxy-8-quinolinethiolates
of tin(II), vanadium(IV), and molybdenum(VI) has been synthesized. Their cytotoxicity on HT-1080 tumor cells (human fibrosarcoma)
and MG-22A (mouse hepatoma) cells has been studied. It was established that all of the investigated complexes of 8-quinolinethiol
and majority of the complexes of 8-quinolinethiol derivatives possessed very high cytotoxicity towards both cell lines. Their
toxicity in relation to mouse embryo fibroblasts NIH 3T3 depended on the position of the substituent in the quinoline ring.
Complexes of tin and vanadium with 4-methyl-, 5-methyl-, and 6-methoxy-8-quinolinethiol derivatives were less toxic. 4-Methyl-,
5-methyl-, and 6-methoxy-8-quinolinethiolates of vanadium demonstrated the highest selectivity of cytotoxic action. 相似文献
99.
E. Lukevics D. Jansone L. Leite J. Popelis G. Andreeva I. Shestakova I. Domracheva V. Bridane I. Kanepe 《Chemistry of Heterocyclic Compounds》2009,45(10):1226-1234
A series of phenylvinyl derivatives of 4,6,6-trimethyl-2-oxo-1,2,5,6-tetrahydropyridine-3-carbonitriles has been synthesized
and their cytotoxic activity towards HT-1080 (human fibrosarcoma) and MG 22A (mouse hepatoma) tumor cells studied. It was
found that the 2-nitro-, 2- and 3-chloro, 2-fluoro, and 2-bromophenyl derivatives showed high cytotoxic activity towards both
cell lines. The toxicity towards NIH 3T3 normal mouse embryonic fibroblasts depends on the nature and position of the substituent
in the phenyl ring. The greatest selectivity of cytotoxic effect was seen in the 2-bromophenyl derivative. 相似文献
100.
M. Vorona I. Potorochina G. Veinberg S. Belyakov I. Shestakova I. Kanepe E. Lukevics 《Chemistry of Heterocyclic Compounds》2009,45(12):1532-1538
The sulfoxide of 6Z-[2-(methoxyimino)propylidene]penicillanic acid tert-butyl ester and the sulfones of 6Z-[2-(hydroxyimino-, methoxyimino-, benzyloxyimino-, 2-bromo- and 4-bromobenzyloxyimino)-propylidene]penicillanic acid in the
syn and anti forms have been synthesized by the condensation of the sulfoxide and sulfone of 6Z-acetylmethylenepenicillanic acid tert-butyl ester with hydroxylamine, methoxyamine, benzyloxyamine, 2-bromo- and 4-bromobenzyloxyamines. The syn and anti isomers
of 3Z-(2-methoxyiminopropylidene)-4R-(benzothiazolyl-2-dithio)-2-oxoazetidinyl-1R-(2-propenyl)acetic acid tert-butyl ester were obtained by opening of the thiazolidine ring in 6Z-[2-(methoxy-imino)propylidene]-1-oxopenicillanic acid tert-butyl ester with 2-mercaptobenzothiazole. The 3Z-(2-methoxyiminopropylidene)-4R-(methylsulfonyl)-2-oxoazetidinyl-1-(2-propylidene)acetic acid tert-butyl ester was synthesized by the interaction of 1,8-diazobicyclo[5.4.0]undec-7-ene and methyl iodide with 6Z-[2-(methoxyimino)propylidene]-1,1-dioxopenicillanic acid tert-butyl ester. A dependence of the cytotoxic effect in relation to cancer and normal cells in vitro on the structure of the
substituent in position 6 and the syn and anti isomerism of the oxyimino group was established for the synthesized compounds. 相似文献