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61.
Naringenin (NR) displays strong antioxidant and numerous pharmacological activities, mitigating severity of metabolic‐syndromes without undesirable side‐effects. With the upsurge of interest in administering NR as diet‐supplement antioxidant, in this work for the first time we implemented functionalized‐MWCNT/Nileblue‐composite on carbon paste electrode (fMWNCT/NB/MCPE), as electrochemical sensor for catalytic NR oxidation. Integrated properties of fMWCNT/NB and their consonance with CPE, led to lowering of Rct value with fast‐kinetics and diminution of over‐potential. NR determination was due to electrical‐conductivity, π‐π and electrostatic‐forces that magnified anodic current by 5.5 fold. In the pH range 3.0 to 10.0 NR undergoes irreversible oxidation via transfer of 1e?/H+. Critical parameters, namely, pH and scan rate were assessed to reinforce differential pulse voltammtery (DPV) sensitivity for quantitative measurements. Sensor's selectivity, stability, accuracy and reproducibility were determined. Finally its viability in quantifying NR was validated by scrutinizing NR fortified fruit juices, as real sample matrices.  相似文献   
62.
In this study, highly purified galactomannan containing fenugreek gum was isolated by newly reported method and investigated for its surface and emulsification property. Comparative studies were carried out with other galactomannan containing natural emulsifiers like locust bean gum, guar gum, and non-galactomannan anionic xanthan gum. The results revealed that highly purified fenugreek gum has better surface and interfacial tension reducing property among all gums used in this study. Emulsion prepared with 0.6% highly purified fenugreek gum showed greater reduction in droplets size with greater surface area compared to guar gum, locust bean gum, and xanthan gum emulsion. Zeta potential values indicated that highly purified fenugreek gum emulsion showed greater repulsive forces and was able to form more stable emulsion compared to other gums. No coalescence or phase separation was observed during storage.   相似文献   
63.
Chemical analysis of a marine-derived Streptomyces sp. (CMB-M0392) isolated from sediment collected off Heron Island, Queensland, Australia, yielded a new benzothiazine ansamycin, heronamycin A. The absolute stereostructure of heronamycin A was determined by detailed spectroscopic analysis and X-ray crystallography. Heronamycin A exhibited modest antimicrobial activity against Bacillus subtilis strains ATCC 6051 and 6633 (IC50 = 18 and 14 μM, respectively).  相似文献   
64.
65.
Cellulose - Pulp, paper, and related industries consume large amount of commercial alkali to process raw fiber and/or recycle waste. A low-cost alternative to commercial alkali would be useful to...  相似文献   
66.
The addition of 2 mol% P2O5 to stoichiometric K-fluorrichterite (KNaCaMg5Si8O22F2, KFR) has been reported to enhance the mechanical properties and improve the in vitro biocompatibility of this glass-ceramic by promoting the formation of enstatite and fluorapatite (FA). Here, the effect of further increasing the P2O5 concentration on phase evolution of KFR has been investigated. XRD data showed that mica crystallized in samples with 4 and 5 mol% P2O5 (GP4 and GP5, respectively) at 650 °C, but no diopside was detected at higher temperatures, in contrast with the general phase evolution in KFR based glass-ceramics. More importantly, however, the addition of ?4 mol% P2O5 induced phase separation of the glass into a silica glass matrix and phosphate rich droplets prior to crystallization. EDS traces taken from samples heat-treated at 600 °C, revealed that the silica glass matrix was deficient in Mg and unlikely to be the host for crystallization of mica. Conversely, the P2O5 rich regions contained excess Mg and were considered to be the host for the formation of mica and FA.  相似文献   
67.
We study the regularity, Palais-Smale characterization and existence/nonexistence of solutions of the Hardy-Sobolev-Maz'ya equation in a bounded domain in RN where xRN is denoted as x=(y,z)∈Rk×RNk and . We show different behaviors of PS sequences depending on t=0 or t>0.  相似文献   
68.
The plasma which consists of one species of electrons, one hot species and another cold species of ions has been considered. By using reductive perturbation method it has been shown that the nonlinear ion-acoustic waves in unmagnetized plasmas are governed by the Korteweg-de Vries equation. The mixture of hot species of ions as impurity in the plasmas has been discussed. The effects due to the presence of hot species of ions on the Landau damping has also been considered.  相似文献   
69.
Amaryllidaceae is a significant source of bioactive phytochemicals with a strong propensity to develop new drugs. The genera Allium, Tulbaghia, Cyrtanthus and Crinum biosynthesize novel alkaloids and other phytochemicals with traditional and pharmacological uses. Amaryllidaceae biomolecules exhibit multiple pharmacological activities such as antioxidant, antimicrobial, and immunomodulatory effects. Traditionally, natural products from Amaryllidaceae are utilized to treat non-communicable and infectious human diseases. Galanthamine, a drug from this family, is clinically relevant in treating the neurocognitive disorder, Alzheimer’s disease, which underscores the importance of the Amaryllidaceae alkaloids. Although Amaryllidaceae provide a plethora of biologically active compounds, there is tardiness in their development into clinically pliable medicines. Other genera, including Cyrtanthus and Tulbaghia, have received little attention as potential sources of promising drug candidates. Given the reciprocal relationship of the increasing burden of human diseases and limited availability of medicinal therapies, more rapid drug discovery and development are desirable. To expedite clinically relevant drug development, we present here evidence on bioactive compounds from the genera Allium, Tulgbaghia, Cyrtanthus and Crinum and describe their traditional and pharmacological applications.  相似文献   
70.
Molineria recurvata (MR) has been traditionally used to manage diabetes mellitus in India. However, the molecular mechanism of MR on the diabetic-induced nephropathy has not been clearly investigated. Thus, this study investigates the protective effects of the MR extract on nephropathy in streptozotocin (STZ)-induced diabetic rats. Diabetes was instigated by a single intraperitoneal injection of STZ (45 mg/kg) in male Sprague-Dawley rats. Once the diabetes was successfully induced, the MR extract (200 mg/kg/day) or metformin (200 mg/kg/day) was orally administered for 14 days. Renal function, morphology changes and levels of inflammatory cytokines were measured. Blood glucose concentrations were considerably reduced in STZ-induced diabetic rats following treatment with the MR extract. The administration of the MR extract substantially restored the abnormal quantity of the oxidative DNA damage marker 8-hydroxy-2′-deoxy-guanosine (8-OHdG), malondialdehyde, glutathione, oxidized glutathione, superoxide dismutase, catalase, interleukin (IL)-1β, IL-6, IL-10, and transforming growth factor-β (TGF-β). The urinary excretion of kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL), selenium binding protein 1 (SBP1), and pyruvate kinase M2 (PKM2) was significantly reduced in diabetes rats after administration of the MR extracts. In the kidneys of STZ-induced diabetic rats, the MR extracts markedly downregulated the expression of fibronectin, collagen-1, and α-smooth muscle actin (α-SMA). In particular, the MR extracts markedly increased the level of SIRT1 and SIRT3 and reduced claudin-1 in the kidney. These results suggest that the MR extracts exhibits therapeutic activity in contrast to renal injury in STZ-induced diabetic rats through repressing inflammation and oxidative stress.  相似文献   
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