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排序方式: 共有263条查询结果,搜索用时 15 毫秒
191.
Imran Ahmad Khan Matloob Ahmad Usman Ali Ashfaq Sadia Sultan Magdi E.A. Zaki 《Molecules (Basel, Switzerland)》2021,26(16)
α-Glucosidase inhibitors (AGIs) are used as medicines for the treatment of diabetes mellitus. The α-Glucosidase enzyme is present in the small intestine and is responsible for the breakdown of carbohydrates into sugars. The process results in an increase in blood sugar levels. AGIs slow down the digestion of carbohydrates that is helpful in controlling the sugar levels in the blood after meals. Among heterocyclic compounds, benzimidazole moiety is recognized as a potent bioactive scaffold for its wide range of biologically active derivatives. The aim of this study is to explore the α-glucosidase inhibition ability of benzimidazolium salts. In this study, two novel series of benzimidazolium salts, i.e., 1-benzyl-3-{2-(substituted) amino-2-oxoethyl}-1H-benzo[d]imidazol-3-ium bromide 9a–m and 1-benzyl-3-{2-substituted) amino-2-oxoethyl}-2-methyl-1H-benzo[d] imidazol-3-ium bromide 10a–m were screened for their in vitro α-glucosidase inhibitory potential. These compounds were synthesized through a multistep procedure and were characterized by 1H-NMR, 13C-NMR, and EI-MS techniques. Compound 10d was identified as the potent α-glucosidase inhibitor among the series with an IC50 value of 14 ± 0.013 μM, which is 4-fold higher than the standard drug, acarbose. In addition, compounds 10a, 10e, 10h, 10g, 10k, 10l, and 10m also exhibited pronounced potential for α-glucosidase inhibition with IC50 value ranging from 15 ± 0.037 to 32.27 ± 0.050 µM when compared with the reference drug acarbose (IC50 = 58.8 ± 0.12 μM). A molecular docking study was performed to rationalize the binding interactions of potent inhibitors with the active site of the α-glucosidase enzyme. 相似文献
192.
Sadia Faiz Ameer Fawad Zahoor Muhammad Ajmal Shagufta Kamal Sajjad Ahmad Abdelrahman M. Abdelgawad Mehrez E. Elnaggar 《Journal of heterocyclic chemistry》2019,56(10):2839-2852
Novel structural hybrids of benzofuran–oxadiazole and benzofuran–triazole have been synthesized and evaluated for their potential against Staphylococcus aureus, Bacillus subtilis, and Escherichia coli. The excellent antibiotic activity was shown by compounds 5c and 9c against S. aureus with minimum inhibitory concentration values in 1.74–5.16 mg/mL range. The estimation of in vitro antifungal activity of synthetic compounds was performed against Trichoderma harzianum, Aspergillus niger, and Metarhizium anisopliae. Among compounds 5a – 5j , only 5h and 5i showed promising antifungal potential against T. harzianum and A. niger, whereas compound 5j showed enhanced antifungal effect only against A. niger when their activity values were compared with standard drug amphotericin. No pronounced antifungal activity was shown by synthesized compounds 9a–j , except for compound 9g , which was active against all fungal strains having minimum inhibitory concentration values in 1.90–2.03 mg/mL range. In addition to antimicrobial evaluation, the synthesized compounds were also analyzed to study their effects on the catalytic potential of laccase, and it was found that among all, compound 9b showed very strong activity with maximum relative reactivity of 145% at 0.03‐mM concentration. 相似文献
193.
This paper shows how the structure and dynamics of a lightlike thin shell in general relativity can be obtained from a distributional approach. 相似文献
194.
Manganese Oxide Nanoparticles/Reduced Graphene Oxide as Novel Electrochemical Platform for Immobilization of FAD and its Application as Highly Sensitive Persulfate Sensor 下载免费PDF全文
In this study, manganese oxide nanoparticles/reduced graphene oxide(MnOxNPs/rGO) was used as support for strong immobilization of flavin adenine dinucleotide(FAD). A thin film of rGO cast on the electrode surface, followed by performing electrodeposition of MnOxNPs at applied constant potential of +1.4 V vs. Ag/AgCl for 200 s. Finally, FAD was electrodeposited onto the rGO/MnOxNPs film by potential cycling between 1.0 to ?1.0 V in solution containing 1 mg ml?1 FAD. Electrochemical properties and catalytic activity of GCE/rGO‐MnOxNPs/FAD toward persulfate (S2O82?) reduction was investigated. Under optimized condition, the concentration calibration range, detection limit, and sensitivity were 0.1 μM–2 mM, 90 nM and 125.8 nA/μM, respectively, using hydrodynamic amperometry technique. 相似文献
195.
Wajeehah Shahid K. A. Bhatti Sadia Zafar Anwar-ul-Haq Fazal-e-Aleem 《辐射效应与固体损伤》2016,171(11-12):936-942
Laser irradiation effects on morphological, structural and mechanical properties of copper are explored. The targets are exposed by employing low-cost continuous wave (CW) laser (wavelength of 532?nm) in air. The surface morphology, structural and mechanical modification of irradiated targets was investigated by scanning electron microscopy (SEM) (Fei, Quanta 250), an X-ray diffractrometer (XRD) (DMAX III ARigaku, Japan) and a Vickers hardness tester, respectively. The SEM analysis revealed the exfoliation sputtering, electronic sputtering, thermal stresses and cracks. The grain size, dislocation line density, relative intensity and d-spacing of irradiated metals were studied by XRD. Micro hardness is found to increase with the increase in time of laser irradiation, in accordance with the Vickers hardness tester. This work provides a cost-effective, user-friendly and easy-to-handle study of several properties of irradiated targets with good results. 相似文献
196.
The microbial transformation of (+)-adrenosterone (1) by Cephalosporium aphidicola afforded three metabolites identified as androsta-1,4-diene-3,11,17-trione (2), 17beta-hydroxyandrost-4-ene-3,11-dione (3) and 17beta-hydroxyandrosta-1,4-diene-3,11-dione (4). The fermentation of 1 with Fusarium lini also produced metabolites 2 and 4, while the fermentation with Trichothecium roseum afforded metabolite 3. The structures of transformed products were determined by spectroscopic methods. 相似文献
197.
Ahmad VU Iqbal S Kousar F Bader S Arshad S Tareen RB 《Chemical & pharmaceutical bulletin》2005,53(9):1126-1130
Phytochemicals investigation of the whole plant of Zygophyllum atriplicoides resulted in the isolation of two new triterpenoidal saponins together with a known compound. The structure of the new compounds atriplicosaponin A (1) and atriplicosaponin B (2) were established as 3-O-[alpha-D-glucopyranosyl-(1-->2)-beta-D-xylopyranosyl]-hederagenin and 27 alpha-hydroxyurs-12-ene-3-O-[beta-D-glucopyranosyl(1-->4)(2-O-sulpho)-beta-D-quinovopyranoside] and known compound was identified as 3-O-[beta-D-glucopyranosyl]-beta-sitosterol. The structure elucidations of the compounds were based primarily on 1D and 2D-NMR analysis, including COSY, HMBC and HMQC correlations. 相似文献
198.
Arabi Malika Elias Abdelhamid Kamel Ziane Ait younes Yasmine Mansouri Belkacem Toumert Idir 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):1095-1106
Journal of Radioanalytical and Nuclear Chemistry - Gamma irradiation was applied to olive mill wastewater and synthetic samples prepared from Gallic acid. The effects, generated on the... 相似文献
199.
Dr. Nafees Muhammad Prof. Tan Cai-Ping Dr. Sadia Nasreen Prof. Zong-Wan Mao 《化学:亚洲杂志》2021,16(16):2276-2279
A mitochondria targeting dual-action platinumIV prodrug exhibits high anticancer activity in triple negative breast cancer cells. The complex intervenes in several cellular processes including DNA damage, perturbation of mitochondrial bioenergetics and induction of necrosis to kill cancer cells. 相似文献
200.