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1.
Summary Excitation functions of proton induced nuclear reactions on natural Te were investigated up to 18 MeV. Cross sections for production of 121,123,124,126,128,130gI and 121gTe were measured. The new experimental data were compared with the results of ALICE-IPPE model calculations and with data found in the literature and measured on natural or enriched Te targets. The new data can be effectively used for validation of recommended cross sections of medically relevant 123I and 124I.  相似文献   
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Experimental data suggest that Resveratrol, a compound found in grapes and other fruits may influence cell proliferation and apoptosis. The aim of our experiments was to study the effect of Resveratrol on tumor cell cultures and an endothelial cell culture in order to examine the effect of various doses of this compound on active cell death and cell proliferation. Human tumor (HT-29, SW-620, HT-1080) and endothelial (HUV-EC-C) cells were treated with various doses of (0.1 to 100.0 microg/ml) Resveratrol in vitro. Cell number, apoptotic and mitotic index was measured 24, 48 and 72 h after treatment. Low doses (0.1-1.0 microg/ml) of Resveratrol enhance cell proliferation, higher doses (10.0-100.0 microg/ml) induce apoptosis and decrease mitotic activity, which is reflected in changes of cell number. Resveratrol influences dose dependently the proliferative and apoptotic activity of human tumor and endothelial cells. The possible role of formaldehyde in the mechanism of action of Resveratrol is discussed.  相似文献   
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A. Kiréva 《Mikrochimica acta》1976,66(1-2):211-215
Résumé Le présent travail constitue une application analytique de nos recherches sur l'interaction des complexes interhalogénés de l'iode au moyen de diantipyrilméthane (DAM). On à étudié les conditions d'échange des ligands chlore et iode dans le complexe extrasphérique DAMH3 [ICl2]3. Sur la base de cet échange on a élaboré une méthode photométrique de détermination de microquantités d'ions iodures, soit 1 à 10g d'ions iodures par ml. Les ions Br, Cl, NO3 , SO4 2, C2O4 2– ne gênent pas la détermination.
Investigation of the interaction of certain iodine complexes by means of diantipyrilmethane (DAM). II
Summary The present paper constitutes an analytical application of our studies on the interaction of interhalogen complexes of iodine by means of diantipyrilmethane (DAM). The exchange conditions of the chlorine and iodine ligands in the extraspheric complex DAMH3 (ICl2)3 have been examined. On the basis of this exchange a photometric method of determining microquantities of iodide ions (1 to 10g iodide ions per ml) has been developed. The ions Br, Cl, SO4 2–, C2O4 2– do not interfere with the determination.

Zusammenfassung Die Ergebnisse unserer Untersuchungen über die Reaktion von Interhalogenkomplexen des Jods mit Diantipyrilmethan (DAM) wurden für analytische Zwecke verwendet. Die Bedingungen für den Austausch der Liganden Chlor und Jod im außersphärischen Komplex (DAM)H3 · [JCl2]3 wurden untersucht. Auf der Grundlage dieses Austausches wurde eine photometrische Methode zur Bestimmung von Mikromengen, d. h. 1–10g Jodid/ml ausgearbeitet. Br, Cl, NO3 , SO4 2–, C2O4 2– stören die Bestimmung nicht.
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Ageratum conyzoides L. (Family—Asteraceae) is an annual aromatic invasive herb, mainly distributed over the tropical and subtropical regions of the world. It owns a reputed history of indigenous remedial uses, including as a wound dressing, an antimicrobial, and mouthwash as well as in treatment of dysentery, diarrhea, skin diseases, etc. In this review, the core idea is to present the antifungal potential of the selected medicinal plant and its secondary metabolites against different fungal pathogens. Additionally, toxicological studies (safety profile) conducted on the amazing plant A. conyzoides L. are discussed for the possible clinical development of this medicinal herb. Articles available from 2000 to 2020 were reviewed in detail to exhibit recent appraisals of the antifungal properties of A. conyzoides. Efforts were aimed at delivering evidences for the medicinal application of A. conyzoides by using globally recognized scientific search engines and databases so that an efficient approach for filling the lacunae in the research and development of antifungal drugs can be adopted. After analyzing the literature, it can be reported that the selected medicinal plant effectively suppressed the growth of numerous fungal species, such as Aspergillus, Alternaria, Candida, Fusarium, Phytophthora, and Pythium, owing to the presence of various secondary metabolites, particularly chromenes, terpenoids, flavonoids and coumarins. The possible mechanism of action of different secondary metabolites of the plant against fungal pathogens is also discussed briefly. However, it was found that only a few studies have been performed to demonstrate the plant’s dosage and safety profile in humans. Considered all together, A. conyzoides extract and its constituents may act as a promising biosource for the development of effective antifungal formulations for clinical use. However, in order to establish safety and efficacy, additional scientific research is required to explore chronic toxicological effects of ageratum, to determine the probability of interactions when used with different herbs, and to identify safe dosage. The particulars presented here not only bridge this gap but also furnish future research strategies for the investigators in microbiology, ethno-pharmacology, and drug discovery.  相似文献   
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The mechanism of interaction of trypsin with the sulfathiazole was studied through using fluorescence quenching and UV-visible absorption spectra at pH 7.4. The Stern-Volmer quenching constants, binding constants, number of binding sites and the corresponding thermodynamic parameters ΔHo, ΔSo and ΔGo were calculated at different temperatures. The effect of common metal ions on the constants was also discussed. The results suggest that sulfathiazole can interact strongly trypsin and that there is the formation of trypsin-sulfathiazole complex and the interaction can be explained on the basis of hydrogen bonds and van der Waals forces. The binding distance (r) between the donor (trypsin) and acceptor (sulfathiazole) was 3.52 nm based on the Förster’s non-radiative energy transfer theory. The detection and quantification limits of sulfathiazole were calculated as 2.52 and 8.40 μM in the presence of trypsin, respectively. The relative standard deviation (RSD) was 4.086 % for determinations (n?=?7) of a sulfathiazole solution with the concentration of 7.54 μM.  相似文献   
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Terpenoid-like bischalcones (3 and 4) were synthesized from the reaction of α- and β-ionones and benzaldehydes in excellent yields. The Michael addition of 1,3-dicarbonyl compounds to bischalcones (3 and 4) resulted in the formation of cyclohexenones derivatives (10a–d and 14a, b) via regioselective addition of 1,3-dicarbonyls and then cyclization.  相似文献   
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