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51.
Firley D Courcot B Gillet JM Fraisse B Zouhiri F Desmaële D d'Angelo J Ghermani NE 《The journal of physical chemistry. B》2006,110(1):537-547
We have established that polyhydroxylated styrylquinolines are potent inhibitors of HIV-1 integrase (IN). Among them, we have identified (E)-8-hydroxy-2-[2-(4,5-dihydroxy-3-methoxyphenyl)-ethenyl]-7-quinolinecarboxylic acid (1) as a promising lead. Previous molecular dynamics simulations and docking procedures have shown that the inhibitory activity involves one or two metal cations (Mg2+), which are present in the vicinity of the active center of the enzyme. However, such methods are generally based on a force-field approach and still remain not as reliable as ab initio calculations with extended basis sets on the whole system. To go further in this area, the aim of the present study was to evaluate the predictive ability of the electron density and electrostatic properties in the structure-activity relationships of this class of HIV-1 antiviral drugs. The electron properties of the two chemical progenitors of 1 were derived from both high-resolution X-ray diffraction experiments and ab initio calculations. The twinning phenomenon and solvent disorder were observed during the crystal structure determination of 1. Molecule 1 exhibits a planar s-trans conformation, and a zwitterionic form in the crystalline state is obtained. This geometry was used for ab initio calculations, which were performed to characterize the electronic properties of 1. The electron densities, electrostatic potentials, and atomic charges of 1 and its progenitors are here compared and analyzed. The experimental and theoretical deformation density bond peaks are very comparable for the two progenitors. However, the experimental electrostatic potential is strongly affected by the crystal field and cannot straightforwardly be used as a predictive index. The weak difference in the theoretical electron densities between 1 and its progenitors reveals that each component of 1 conserves its intrinsic properties, an assumption reinforced by a 13C NMR study. This is also shown through an excellent correlation of the atomic charges for the common fragments. The electrostatic potential minima in zwitterionic and nonzwitterionic forms of 1 are discussed in relation with the localization of possible metal chelation sites. 相似文献
52.
In this paper, the metric approach of f(R) theory of gravity is used to investigate the exact vacuum solutions of spatially homogeneous rotating spacetimes. For this purpose, R is replaced by f(R) in the standard Einstein-Hilbert action and the set of modified Einstein field equations reduce to a single equation. We adopt the assumption of constant Ricci scalar which maybe zero or non-zero. Moreover, the energy density of the non-trivial solution has been evaluated by using the generalized Landau-Lifshitz energy-momentum complex in the perspective of f(R) gravity for some appropriate f(R) model, which turns out to be a constant quantity. 相似文献
53.
54.
Fatima Ijaz Syed Salman Shafqat Hafiz Adnan Ahamd Munawar Ali Munawar Misbahul Ain Khan 《Journal of heterocyclic chemistry》2019,56(4):1231-1238
Derivatives of ninhydrin are extensively used in the field of forensic sciences as important latent fingerprint reagents. Many works have been performed upon their synthesis and reactivity, but there are many spaces to work on the compounds of quinoline‐2,3,4(1H)‐triones—analogues of ninhydrin, in both dimensions: synthesis and reactivity, and according to the best of our knowledge, not a single detailed or short compiled article has been published for these compounds. This review briefly summarizes the chemistry of quinoline‐2,3,4(1H)‐triones. 相似文献
55.
Annemarie Marckwordt Fatima ElOuahabi Hadis Amani Sergey Tin Narayana V. Kalevaru Paul C. J. Kamer Sebastian Wohlrab Johannes G. deVries 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(11):3524-3528
Use of ZrO2/SiO2 as a solid acid catalyst in the ring‐opening of biobased γ‐valerolactone with methanol in the gas phase leads to mixtures of methyl 2‐, 3‐, and 4‐pentenoate (MP) in over 95 % selectivity, containing a surprising 81 % of M4P. This process allows the application of a selective hydroformylation to this mixture to convert M4P into methyl 5‐formyl‐valerate (M5FV) with 90 % selectivity. The other isomers remain unreacted. Reductive amination of M5FV and ring‐closure to ?‐caprolactam in excellent yield had been reported before. The remaining mixture of 2‐ and 3‐MP was subjected to an isomerising methoxycarbonylation to dimethyl adipate in 91 % yield. 相似文献
56.
Dr. Jakob-Jonathan Maudrich Max Widemann Fatima Diab Ralf H. Kern Dr. Peter Sirsch Dr. Christian P. Sindlinger Dr. Hartmut Schubert Prof. Dr. Lars Wesemann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(70):16081-16087
Organodihydridoelement anions of germanium and tin were reacted with metallocene dichlorides of Group 4 metals Ti, Zr and Hf. The germate anion [Ar*GeH2]− reacts with hafnocene dichloride under formation of the substitution product [Cp2Hf(GeH2Ar*)2]. Reaction of the organodihydridostannate with metallocene dichlorides affords the reduction products [Cp2M(SnHAr*)2] (M=Ti, Zr, Hf). Abstraction of a hydride substituent from the titanium bis(hydridoorganostannylene) complex results in formation of cation [Cp2M(SnAr*)(SnHAr*)]+ exhibiting a short Ti–Sn interaction. (Ar*=2,6-Trip2C6H3, Trip=2,4,6-triisopropylphenyl). 相似文献
57.
Abdulmumeen A. Hamid Olapeju O. Aiyelaagbe Arvind S. Negi Fatima Kaneez Suaib Luqman Stephen O. Oguntoye 《Natural product research》2019,33(2):296-301
Chloroform extract from the leaves of Turraea vogelii Hook f. ex Benth demonstrated cytotoxic activity against a chronic myelogenous leukemia cell, K-562 with IC50 of 14.27 μg/mL, while chloroform, ethyl acetate and methanol extracts from the stem of the plant inhibited K-562 cells growth with IC50 of 19.50, 24.10 and 85.40 μg/mL respectively. Bioactive chloroform extract of Turraea vogelii leaves affords two triterpenoids: oleana-12,15,20-trien-3β-ol (1), and oleana-11,13-dien-3β,16α,28-triol (2), with six fatty esters, ethyl hexaeicos-5-enoate (3), 3-hydroxy-1,2,3-propanetriyltris(tetadecanoate) (4), 1,2,3-propanetriyl(7Z,7′Z,7′′Z)tris(-7-hexadecenoate) (5), 1,2,3-propanetriyl(5Z,5′Z,5′′Z)tris(-5-hexadecenoate) (6), 1,2,3-propanetriyltris(octadecanoate) (7), and 2β-hydroxymethyl tetraeicosanoate (8). Tetradecane (9), four fatty acids: hexadecanoic acid (10), tetradecanoic acid (11), (Z)-9-eicosenoic acid (12), and ethyl tetradec-7-enoate (13) were isolated from chloroform extract of Turraea vogelii stem. 1,2,3-propanetriyltris(heptadecanoate) (14), (Z)-9-octadecenoic acid (15) and (Z)-7-tetradecenoic acid (16) were isolated from ethyl acetate extract while (Z)-5-pentadecenoic acid (17) was obtained from methanol extract of the plant stem. Compounds 1, 2, 5, 6, 11, 12, 15, 16 and 17 exhibited pronounced antiproliferative activity against K-562 cell lines. 相似文献
58.
Muhammad Zafar Irshad Khan Syeda Saniya Zahra Madiha Ahmed Humaira Fatima Bushra Mirza Ihsan-ul Haq 《Natural product research》2019,33(14):2099-2104
Ipomoea carnea Jacq. is an important folklore medicinal plant, assessed for its underexplored biological potential. Antioxidant, cytotoxic, antiproliferative and polyphenolic profile of whole plant was evaluated using various techniques. Maximum extract recovery (29% w/w), phenolic [13.54 ± 0.27 μg GAE/mg dry weight (DW)] and flavonoid (2.11 ± 0.10 μg QE /mg DW) content were recorded in methanol-distilled water (1:1) flower extract. HPLC-DAD analysis quantified substantial amount of six different polyphenols ranging from 0.081 to 37.95 μg/mg extract. Maximum total antioxidant and reducing potential were documented in methanol-distilled water and acetone-distilled water flower extracts (42.62 ± 0.47 and 24.38 ± 0.39 μg AAE/mg DW) respectively. Ethanol-chloroform root extract manifested highest free radical scavenging (IC50 of 61.22 μg/mL) while 94.64% of the extracts showed cytotoxicity against brine shrimps. Ethanol leaf extract exhibited remarkable activity against THP-1 cell line (IC50 = 8 ± 0.05 μg/mL) and protein kinases (31 mm phenotype bald zone). 相似文献
59.
Rabia Javeed Dilshad Hussain Fahmida Jabeen Adeela Saeed Batool Fatima Muhammad Naeem Ashiq Muhammad Najam-ul-Haq 《Biomedical chromatography : BMC》2020,34(1):e4693
High-density lipoproteins (HDLs) have anti-inflammatory and antioxidant properties and are potentially cardio-protective. Defective HDL function is caused by alterations in both the proteome and lipidome of HDL particles. As potential biomarkers, the development of analytical methods is necessary for the enrichment of HDLs. Therefore, a method for selective enrichment of HDLs using immobilized metal ion affinity chromatography (IMAC) and metal oxide affinity chromatography (MOAC) is presented. SPE-based isolation of HDLs from whole serum is adopted as an alternative to traditional ultracentrifugation methods followed by SDS–PAGE. The enrichment mechanism relies on isoelectric points of lipoproteins and metal oxide. Negatively charged lipoprotein particles interact with positively charged metal oxides and IMAC affinity, which acts as a cation. Identified proteins from HDL through MALDI–MS analysis are apo AI, AII, AIV, CI, CIII, E, J, M, H, serum amyloid A and other nonapoproteins that are part of HDL particles and perform cellular functions. This serum-based proteomics approach gives insight into the functional role of HDL. HDL-associated phospholipids have also been analyzed by LDI–MS. Results suggest that the adopted analytical strategy is a feasible idea to extract lipoproteins from serum. A comparative study of healthy and diseased samples using this approach will provide valuable information in future. 相似文献
60.
Mameri Fatima Koutchoukali Ouahiba Koutchoukali Mohamed Salah Hartwig Anne Nemdili Leila Ulrich Joachim 《Journal of Thermal Analysis and Calorimetry》2019,136(2):833-842
Journal of Thermal Analysis and Calorimetry - The aim of this work is to apply the melt crystallization technology to manufacture ibuprofen tablets coated with polyethylene glycol in a single step.... 相似文献