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1.
Blossoms of Inula nervosa Wall. (BINW) are traditionally used as an analgesic and antitussive in China. In this study, in vitro anticomplementary activities of crude extract from BINW in 21 batches and of extracts of four monomeric compounds were evaluated by the classical pathway. The effect of the region of origin on the quality of BINW was evaluated by fingerprint analysis for the first time. Furthermore, chemometric methods including similarity analysis and principal component analysis were employed to evaluate the quality of BINW. The nine major monomeric compounds were quantitated by ultra‐high‐performance liquid chromatography. All nine analytes demonstrated excellent linearity with recoveries ranging from 97.25% to 102.76%. The limits of detection and quantification were 0.07–12.20 μg/mL and 0.22–40.27 μg/mL, respectively. Results indicate that different regions of origin have a significant effect on the quality of BINW. Fingerprint analysis in combination with chemometrics and multi‐ingredient determination is an efficient and reliable approach for quality evaluation. The BINW samples from Yunnan had the highest ratio of 1,5‐dicaffeoylquinic acid and thymol; they also exhibited significantly higher anticomplementary activity than those from three other areas. This study successfully established a rapid and efficient method to evaluate the quality and biological activity of BINW.  相似文献   
2.
We report an ecofriendly synthetic approach for the fabrication of biogenic gold nanoparticles (AuNPs) using electron-rich sea cucumber extract as a bio-reductant and stabilizing agent in reducing gold cations into AuNPs at the optimal conditions. The produced AuNPs are spherical in shape with an average particle size of 11 ± 1.5 nm in transmission electron microscopy (TEM) and exhibited a crystal structure of face-centered cubic in X-ray diffraction (XRD) analyses. Our results indicated that bioinspired AuNPs demonstrate superior catalytic activity in the safe and facile one-pot synthesis of polyhydroquinoline derivatives under solvent-free reaction conditions. This green route encompasses multiple benefits including highly recyclable bioinspired catalyst (5 cycles), short reaction times, convenient workout, high to excellent product yields (82%–97%), and nonhazardous conditions.  相似文献   
3.
ABSTRACT

The asymmetric cross-aldol reaction of simple ketones (acetone, cyclohexanone) with isatin derivatives in the presence of crude extract from earthworms as green and effective biocatalyst proceeds easily in MeCN/H2O (1:1) as solvent to afford 3-hydroxy-2-oxindoles derivatives. Ten compounds were synthesized in high yields (62–88%) and moderate ee (29–42%). Structure of the synthesized compounds has been characterized on the basis of NMR spectra and CHN analysis. The ee of the obtained compounds was determined by chiral phase HPLC analysis.  相似文献   
4.
This study aimed to investigate the chemical composition of Tribulus terrestris L. fruit (TT) extract named TT15 and its protective effect against ischemic stroke (IS) as well as corresponding mechanisms. The chemical composition of TT15 was analyzed by liquid chromatography-mass spectrometry (LC-MS), and the compound identification was conducted via searching the in-house database. The LC-MS-based multi-omics approach was applied to search the differential metabolites and differential proteins in rat brain tissue and to explore the biomarker and molecular mechanism of TT15 against middle cerebral artery occlusion (MCAO). A total of 20 compounds were identified from TT15, mainly including alkaloids, flavonoids, phenols, quinones, and esters. These 20 compounds significantly affected the metabolism of 44 metabolites and the expression of 51 proteins. Joint pathway analysis showed that these metabolites and proteins were mainly involved in the response to elevated platelet cytosolic Ca2+ and platelet activation, which inferred that TT15 may exert a protective effect against cerebral ischemic injury via regulating platelet function. This study provides useful information for further exploration of the mechanisms of TT extract against IS.  相似文献   
5.
The aim of the study was the rapid green synthesis of titanium nanoparticles using the aqueous extract of Falcaria vulgaris leaves (TiNPs@FV) and exploring their antioxidant, cytotoxicity, antifungal, antibacterial, and cutaneous wound healing activities under in vitro and in vivo condition. These nanoparticles were characterized by UV-Vis, Fourier transform-infrared(FT-IR), X-ray diffraction XRD), field emission-scanning electron microscopy FE-SEM), and transmission electron microscopy TEM) analyses. The synthesized TiNPs@FV had great cell viability on human umbilical vein endothelial cells and indicted this method was nontoxic. DPPH (2,2-diphenyl-1-picrylhydrazyl) test revealed similar antioxidant potentials for F. vulgaris, TiNPs@FV, and butylated hydroxytoluene. All data of antibacterial, antifungal, and cutaneous wound healing tests were analyzed by SPSS 22 software. In the antimicrobial part of this study, TiNPs@FV indicated higher antifungal and antibacterial effects than all standard antibiotics (p ≤ 0.01). Minimal inhibitory concentration (MIC) and minimal fungicidal concentration of TiNPs@FV against all fungi were at 2–4 mg/mL and 2-8 mg/mL ranges, respectively. But, MIC and minimal bactericidal concentration of TiNPs@FV against all bacteria were at 2-8 mg/mL and 2-16 mg/mL ranges, respectively. In the part of cutaneous wound healing, use of TiNPs@FV ointment significantly (p ≤ 0.01) raised the wound contracture, vessel, hydroxyl proline, hexuronic acid, hexosamine, fibrocyte, and fibrocytes/fibroblast rate and significantly (p ≤ 0.01) decreased the wound area, total cells, neutrophil, and lymphocyte compared to other groups in rats. The results of FT-IR, UV-Vis, XRD, TEM, and FE-SEM confirm that the aqueous extract of F. vulgaris leaves can be used to yield titanium nanoparticles with a notable amount of remedial effects.  相似文献   
6.
To increase the profitability and sustainability of agricultural waste, a facile green approach was established to synthesize zinc oxide nanoparticles (ZnO NPs) using saffron leaf extract as a reducing and stabilizing agent. Structural characteristics of NPs were investigated by X-ray diffraction (XRD), Fourier-transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and UV–Visible (UV–Vis) spectroscopy. Characterization results revealed that ZnO NPs is highly crystalline with a hexagonal wurtzite structure and spherical particles with diameter less than 50 nm, as confirmed by XRD and FESEM techniques. UV–Vis absorption spectra depicted an absorption peak at 370 nm, which confirms the formation of ZnO NPs. FTIR spectral analysis confirmed the presence of functional groups and metal oxygen groups. The biological activities of ZnO NPs were also investigated. The antibacterial effect of ZnO NPs was investigated against selected food pathogens (Salmonella Typhimurium, Listeria monocytogenes, and Enterococcus faecalis). The study results prove that the green synthesized ZnO NPs show enhanced antibacterial activity against S. Typhimurium when compared with other strains. A dose-dependent free radical scavenging activity was observed for ZnO NPs in both 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and fluorescence recovery after photobleaching (FRAP) assays. The ZnO NPs were evaluated for their photocatalytic activity during the degradation of methylene blue (MB) dye in aqueous solutions. The maximum removal of MB achieved was 64% with an initial ZnO NP concentration of 12 mg/mL under UV light. The present study revealed that the agricultural waste (saffron leaf) provides a simple and eco-friendly option to sustainably synthesize ZnO NPs for use as a photocatalyst. In addition, this is the first report on saffron leaf-mediated synthesis of ZnO NPs.  相似文献   
7.
Eucommia ulmoides Oliv. (E. ulmoides) is a valuable and nourishing medicinal herb in China that has been used in the treatment of hypertension. Given the fact that most traditional Chinese medicine is mainly used to treat disease, investigating the pharmacokinetics of traditional Chinese medicines in the pathological state is more useful than that in the normal state. However, the differences in the absorption kinetics of active ingredients of E. ulmoides extract between pathological and physiological conditions have not been reported. Therefore, in this study, the rat intestinal in situ circulatory perfusion model was used to investigate the differences in absorption kinetics of seven active ingredients of E. ulmoides extract in normal and spontaneously hypertensive rats, namely, genipinic acid, protocatechuic acid, neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, (+)-pinoresinol di-O-β-D -glucopyranoside and (+)-pinoresinol 4′-O-β-D -glucopyranoside. Our results indicate that the pathological state of spontaneous hypertension may change the absorption of active components of E. ulmoides extracts, and these findings may provide a reference for improving the rational use of E. ulmoides in the clinic.  相似文献   
8.
This study evaluated the wound healing effects of topical application of an emulsion containing the HPLC-standardised extract from Calophyllum brasiliense Cambess (Clusiaceae) leaves in rats. The macroscopic analysis demonstrated that the wounds treated with the C. brasiliense emulsion healed earlier than the wounds treated with emulsion base and Dersani®. The percentage of wound healing in the group treated with the C. brasiliense emulsion was significantly higher than in the other groups at 7 and 14 days. On day 14, the animals treated with the C. brasiliense emulsion exhibited a 90.67% reduction of the wound areas. The histological evaluation revealed that on day 21, the group treated with the C. brasiliense emulsion exhibited a significant increase in fibroblasts compared with the other groups. Thus, the C. brasiliense emulsion had healing properties in the topical treatment of wounds and accelerated the healing process.  相似文献   
9.
The antibacterial activity of essential oil and methanolic extract of Teucrium polium was determined against Pseudomonas aeruginosa, Pantoea agglomerans, Brenneria nigrifluens, Rhizobium radiobacter, Rhizobium vitis, Streptomyces scabies, Ralstonia solanacearum, Xanthomonas campestris and Pectobacterium cartovorum by disc diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration were determined by using the serial dilution method. Chemical composition of essential oil and methanolic extract was determined by GC-MS and HPLC. α-Pinene (25.769%) and myrcene (12.507) were of the highest percentage in T. polium essential oil, and sinapic acid (15.553 mg/g) and eugenol (6.805 mg/g) were the major compounds in the methanolic extract. Our results indicate that both methanolic extract and essential oil did not show antibacterial activity against P. aeruginosa. Also the essential oil did not show antibacterial activity against P. cartovorum. In general, both methanolic extract and essential oil showed the same antibacterial activity against R. solanacearum, P. agglomerans, B. nigrifluens and S. scabies.  相似文献   
10.
This study describes the in vitro inhibition of protein denaturation of extract/fractions of Withania somnifera and isolated withanolides including 20β hydroxy-1-oxo(22R)-witha-2,5,24 trienolide (1), (20R,22R-14α,20α)-dihydroxy-1-oxowitha-2,5,16,24 tetraenolide (2). The results showed that the extract/fractions of the plant evoked profound inhibitory effect on thermal-induced protein denaturation. The chloroform fraction caused the most dominant attenuation of 68% at 500 μg/mL. The bioactivity-guided isolation from chloroform fraction led to the isolation of compounds 1 and 2 that showed profound protein inhibition with 78.05% and 80.43% effect at 500 μg/mL and thus strongly complimented the activity of extract/fractions. In conclusion, extract/fractions of W. somnifera possessed strong inhibition of protein denaturation that can be attributed to these isolated withanolides.  相似文献   
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