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1.
Md. Zia Uddin Arkajyoti Paul Ahmed Rakib Saad Ahmed Sami Shafi Mahmud Md. Sohel Rana Shahadat Hossain Abu Montakim Tareq Mycal Dutta Talha Bin Emran Jesus Simal-Gandara 《Molecules (Basel, Switzerland)》2021,26(4)
The current study attempted, for the first time, to qualitatively and quantitatively determine the phytochemical components of Elatostema papillosum methanol extract and their biological activities. The present study represents an effort to correlate our previously reported biological activities with a computational study, including molecular docking, and ADME/T (absorption, distribution, metabolism, and excretion/toxicity) analyses, to identify the phytochemicals that are potentially responsible for the antioxidant, antidepressant, anxiolytic, analgesic, and anti-inflammatory activities of this plant. In the gas chromatography-mass spectroscopy analysis, a total of 24 compounds were identified, seven of which were documented as being bioactive based on their binding affinities. These seven were subjected to molecular docking studies that were correlated with the pharmacological outcomes. Additionally, the ADME/T properties of these compounds were evaluated to determine their drug-like properties and toxicity levels. The seven selected, isolated compounds displayed favorable binding affinities to potassium channels, human serotonin receptor, cyclooxygenase-1 (COX-1), COX-2, nuclear factor (NF)-κB, and human peroxiredoxin 5 receptor proteins. Phytol acetate, and terpene compounds identified in E. papillosum displayed strong predictive binding affinities towards the human serotonin receptor. Furthermore, 3-trifluoroacetoxypentadecane showed a significant binding affinity for the KcsA potassium channel. Eicosanal showed the highest predicted binding affinity towards the human peroxiredoxin 5 receptor. All of these findings support the observed in vivo antidepressant and anxiolytic effects and the in vitro antioxidant effects observed for this extract. The identified compounds from E. papillosum showed the lowest binding affinities towards COX-1, COX-2, and NF-κB receptors, which indicated the inconsequential impacts of this extract against the activities of these three proteins. Overall, E. papillosum appears to be bioactive and could represent a potential source for the development of alternative medicines; however, further analytical experiments remain necessary. 相似文献
2.
The template condensation of acetoacetic-2-pyridylamide with amino aliphatic alcohols such as 2-aminoethanol (HL1) and 3-amino propanol (HL2) in the presence of copper(II) ions gave octahedral complexes, which have been characterized by elemental analyses, u.v.-vis. and i.r. spectra, conductivity, d.t.a, magnetic and e.s.r. measurements. The molar conductance in DMF indicate that the complexes are non-ionic in character. The e.s.r. spectra of solid complexes (2) and (5) at room temperature indicate axial type symmetry (dx2-y2) with covalent bond character. 相似文献
3.
In this paper, we introduce a new concept of semi-preemptive scheduling and we show how it can be used to derive a maximum-flow-based lower bound for the P|rj|Lmax which dominates the well-known preemptive lower bound. We show that, in some cases, the proposed bound strictly dominates the preemptive one while having the same complexity. 相似文献
4.
Summary Dielectric measurements on Na2B4O7(99.5%)−V2O5(0.5%) glass system, in the frequency range 10−3 to 104 Hz and temperature range 300 to 500 K, have been carried out. The normalized plots of complex capacitance have shown a single
mechanism responsible for conduction for both volume and surface measurements with their close values of activation energies
(0.67±0.03) eV and (0.64±0.03) eV, respectively. The low-frequency dispersion (LFD) behaviour has been observed to be perturbed
by the presence of more than one competing process. The impedance plots have shown a parallel combination of a capacitor (C) and a resistor (R), with some contribution of a dispersive element due to charge accumulation in the vicinity of the electrodes. The values
ofR andC were found to be of the same order of magnitude, for both surface and volume measurements. The observedR has shown a decrease with an increase in temperature due to an increase in mobility of Na+ ions, whereasC remains practicaly constant. The complex capacitance surface behaviour is dominated by volume, due to hygroscopy of this
glass system. 相似文献
5.
F. M. Elzawawy E. A. Saad I. H. Badr 《Journal of Radioanalytical and Nuclear Chemistry》1992,164(3):141-151
Isotope exchange reaction between NaCl-36 and triphenyltin chloride in dioxane-water (8020% w/w) and ethanol-water (9010% w/w) mixed solvents has been studied at 25, 35 and 50 °C. The exchange reaction was found to proceed via a bimolecular SN2, limiting mechanism with reaction rates depending on the solvent used. Inhibition of the exchange in ethanol-water is probably due to solvation of chloride ion through hydrogen bond formation. The rate laws for the exchange reactions are: Re=3.24×109 e–65550/RT [Rh3SnCl] [NaCl] in dioxanewater and Re=6.61×108 e–69600/RT [Ph3SnCl] [NaCl] in ethanol-water, where is the degree of dissociation of NaCl and Re is the rate of exchange in mol l–1 s–1. The activation parameters H*, S* and G* are reported. 相似文献
6.
7.
Eldefrawi ME Azer NL Nath N Anis NA Bangalore MS O'Connell KP Schwartz RP Wright J 《Applied biochemistry and biotechnology》2000,87(1):25-35
An automated flow fluorometer designed for kinetic binding analysis was adapted to develop a solid-phase competitive fluoroimmunoassay
for urinalysis of opiates. The solid phase consisted of polymer beads coated with commercial monoclonal antibodies (MAbs)
raised against morphine. Fluorescein-conjugated morphine (FL-MOR) was used as the fluorescein-labeled hapten. The dissociation
equilibrium constant (K
D
) for the binding of FL-MOR to the anti-MOR MAb was 0.23 nM. The binding of FL-MOR to the anti-MOR MAb reached steady state within minutes and was displaced effectively by morphine
and other opiates. Morphine-3-glucuronide (M3G), the major urinary metabolite of heroin and morphine, competed effectively
with FL-MOR in a concentration-dependent manner for binding to the antimorphine MAb and was therefore used to construct the
calibration curve. The sensitivity of the assay was 0.2 ng/mL for M3G. The assay was effective at concentrations of M3G from
0.2 to 50 ng/mL, with an IC50 of 2 ng/mL. Other opiates and heroin metabolites that showed >50% crossreactivity when present at 1 μg/mL included codeine,
morphine-6-glucuronide, and oxycodone. Methadone showed very low crossreactivity (<5%), which is a benefit for testing in
patients being treated for opiate addictions. The high sensitivity of the assay and the relatively high cutoff value for positive
opiate tests allows very small sample volumes (e.g., in saliva or sweat) to be analyzed. A double-blind comparison using 205
clinical urine samples showed good agreement between this single-step competitive assay and a commercially performed enzyme
multiplied immunoassay technique for the detection of opiates and benzoylecgonine (a metabolite of cocaine). 相似文献
8.
Saad S. M. Hassan 《Mikrochimica acta》1974,62(1):51-57
Summary A new micromethod for spectrophotometric determination of hydrazine compounds is described. It is based on a reaction withperi-naphthindan-2,3,4-trione hydrate at pH 2.5 to give a red precipitate of dihydroxy-peri-naphthindenone which is dissolved in methanol and measured at 460 nm. The results obtained show an average recovery of 99.8 %, the precision being ± 1 %.
Zusammenfassung Eine neue Mikromethode zur spektrophotometrischen Bestimmung von Hydrazinverbindungen wurde beschrieben. Sie beruht auf der Reaktion mit peri-Naphthindan-2,3,4-trion-hydrat bei pH 2,5, wobei ein roter Niederschlag von Dihydroxy-peri-naphthindenon entsteht, der in Methanol gelöst und bei 460 nm gemessen wird. 99,8% Substanz werden wiedergefunden, die Genauigkeit beträgt ±1%.相似文献
9.
New simple, rapid, accurate, and selective methods are described for microdetermination of the nitro and nitroso groups in organic compounds. These are based on reduction with cadmium metal and 0.05 M HCl whereby 6 and 4 equivalents of the cadmium ions are released per nitro and nitroso groups, respectively. The cadmium ions are measured by atomic absorption spectrometry at 228.8 nm, potentiometrically by titration with EDTA using the cadmium ion selective electrode, and visually by EDTA titration using Eriochrome Black T indicator. Results with an average recovery of 98% and a mean standard deviation of 1.3% are obtainable and no interferences are caused by many nitrogen, oxygen, and sulfur functional groups. 相似文献
10.
The coenzyme pyridoxal-5'-phosphate (PLP) is deiermined by in situ measurement of the rate of ammonia production using a potentiometric gas-sensing membrane electrode. It is shown that the initial rate of ammonia liberation from L-tryptophan by action of tryptophanase apoenzyme and the coenzyme can be linearly related to PLP levels in the nanogram range with minimal interference from related compounds. Calibration data for the 1 × 10-7–2.5 × 10-6 M range for PLP yielded a least-squares equation of rate (mV min-1) = (0.64 ± 0.01) C — 0.01 ± 0.02 with a standard error of 0.02 mV min-1, where concentration, C, is expressed in units of 10-7 mol l-1. 相似文献