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331.
Toxicological Screening of Four Bioactive Citroflavonoids: In Vitro,In Vivo,and In Silico Approaches
Rolffy Ortiz-Andrade Jesús Alfredo Araujo-Len Amanda Snchez-Recillas Gabriel Navarrete-Vazquez Avel Adolfo Gonzlez-Snchez Sergio Hidalgo-Figueroa ngel Josabad Alonso-Castro Irma Aranda-Gonzlez Emanuel Hernndez-Núez Tania Isolina Coral-Martínez Juan Carlos Snchez-Salgado Victor Yez-Prez M. A. Lucio-Garcia 《Molecules (Basel, Switzerland)》2020,25(24)
Many studies describe different pharmacological effects of flavonoids on experimental animals and humans. Nevertheless, few ones are confirming the safety of these compounds for therapeutic purposes. This study aimed to investigate the preclinical safety of naringenin, naringin, hesperidin, and quercetin by in vivo, in vitro, and in silico approaches. For this, an MTT-based cytotoxicity assay in VERO and MDCK cell lines was performed. In addition, acute toxicity was evaluated on Wistar rats by OECD Guidelines for the Testing of Chemicals (Test No. 423: Acute Oral Toxicity-Class Method). Furthermore, we used the ACD/Tox Suite to predict toxicological parameters such as hERG channel blockade, CYP450 inhibition, and acute toxicity in animals. The results showed that quercetin was slightly more cytotoxic on cell lines (IC50 of 219.44 ± 7.22 mM and 465.41 ± 7.44 mM, respectively) than the other citroflavonoids. All flavonoids exhibited an LD50 value > 2000 mg/kg, which classifies them as low-risk substances as OECD guidelines established. Similarly, predicted LD50 was LD50 > 300 to 2000 mg/kg for all flavonoids as acute toxicity assay estimated. Data suggests that all these flavonoids did not show significant toxicological effects, and they were classified as low-risk, useful substances for drug development. 相似文献
332.
Carlos Lodeiro Rufina Bastida Alejandro Macías Adolfo Rodríguez Andre Saint‐Maurice 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e255-e256
The X‐ray structure determinations of the two title compounds, namely 7‐methyl‐7,17‐diaza‐3,11‐diazoniabicyclo[11.3.1]heptadeca‐1(17),13,15‐triene dichloride monohydrate, C14H26N42+·2Cl?·H2O, (I), and 7‐methyl‐17‐aza‐3,7,11‐triazoniabicyclo[11.3.1]heptadeca‐1(17),13,15‐triene 2.826‐chloride 0.174‐nitrate, C14H27N43+·2.826Cl?·0.174NO3?, (II), are reported. Protonation occurs at the secondary amine N atoms in (I) and at all three amine N atoms in (II) to which the Cl? ions are linked via N—H?Cl hydrogen bonds. The macrocyclic hole is quite different in both structures, as is observed by comparing particularly the N3?N4 distances [2.976 (4) and 4.175 (4) Å for (I) and (II), respectively]. In (II), a Cl? ion alternates with an NO3? ion in a disordered structure. 相似文献
333.
334.
Polymerization of propene at −78°C in the presence of a homogeneous catalytic system based on a Ni(II) diimine derivative and methylaluminoxane affords prevailingly syndiotactic crystalline poly(propylene) (rr triad content ≈80%). 13C NMR analysis of the polymer microstructure indicates that the stereochemistry of the monomer insertion is controlled by the configuration of the methine carbon of the growing chain end (unlike-1,3 asymmetric induction). This is the first example of stereospecific homopolymerization of propene promoted by a late transition metal catalyst. 相似文献
335.
Pasquale Longo Fabia Grisi Antonio Proto Adolfo Zambelli 《Macromolecular rapid communications》1998,19(1):31-34
Polymerization of ethylene in the presence of Cp2Ni (Cp: cyclopentadienyl) and methylaluminoxane affords polyethylene of high molecular weight and with high melting point. The same catalyst is active in the polymerization of styrene and 1,3-butadiene to give partially isotactic polystyrene and 1,4-cis-polybutadiene, respectively. 相似文献
336.
Marina Lamberti Mina Mazzeo Daniela Pappalardo Adolfo Zambelli Claudio Pellecchia 《Macromolecular Symposia》2004,213(1):235-252
In the last few years several non-metallocene catalysts have been disclosed as efficient catalysts for the stereospecific polymerization of propene. In this paper we summarize some recent literature data and some new results concerning the stereochemical mechanism of propene polymerization promoted by late transition metal systems and group 4 metal bis(phenoxyimine) systems. NMR analysis of the fine structure of the polymers obtained, in some cases using isotopically enriched reagents, provides valuable information on the regiochemistry and stereochemistry of the polymerization. 相似文献