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1.
Concrete plants accumulate large amounts of concrete wash water. This water, which pH is highly alkaline, has a negative impact on the environment. Its reuse in fresh concrete slightly reduces its mechanical properties. The combination of concrete wash water and zeolitic by-product led to an increase of 4.6% in the compressive strength at 7 days hydration and up to 30% at 28 days hydration. The same combination led to the denser microstructure compared to the samples made with concrete wash water. This could be explained by the pozzolanic reaction of the zeolitic by-product. The complex chemical reactions of cement, zeolitic by-product, and fines presented in the concrete wash water occurred. Therefore, it was suggested the reusing method of concrete wash water together with zeolitic by-product in the fresh concrete mixtures by substituting some amount of tap water with concrete wash water. In this way, the consumption of tap water is possible to reduce in cement systems.  相似文献   
2.
Qualitative and quantitative analysis of flavonoids in the vegetative and reproductive organs of showy tick trefoil [Desmodium canadense (L) DC., Fabaceae] herbs (stems, leaves, buds, inflorescences, legumes, and seeds) collected at various stages of vegetation at the Department of Medicinal Herbs of the Kaunas Botanical Garden (Vytautas Magnus University) was performed using HPLC techniques. A total of 15 flavonoids of aglycon and glycoside nature including apigenin, apigenin-7-O-glycoside, luteolin, rutin, vicenin-2, vitexin, isovitexin, vitexin rhamnoside, orientin, homoorientin, quercitrin, quercetin, hyperoside, astragalin, and kaempferol were identified. Among the vegetative organs, the maximum amount of flvaonoids was found in leaves, where the total content of flavonoids was 23,952.2 mg/g in the budding phase and reached a maximum of 25,472.71 mg/g (2.55%) at the ripening phase (1.88 times greater than in herbs at the beginning of flowering). In stems, the maximum amount of flavonoids (2,318.0 mg/g) was accumulated in the budding phase while the minimum (1,910.77 mg/g) was found at the beginning of seed ripening phase. the maximum amount of flavonoids in the reproductive organs was found in inflorescences, where the total content of flavonoids was 8,164.1 mg/g at the budding phase, reached a maximum of 15,226.39 mg/g in the full flowering phase, and then gradually decreased. Legumes at the beginning of ripening contained 8,892.3 mg/g flavonoids while seeds in the fully ripened phase contained only 4,270.1 mg/g (0.43%) flavonoids. Among the individual flavonoids, orientin and homoorientin predominated in all cases. Thus, not only the inflorescences of showy tick trefoil but also leaves can be used as medicinal raw material. The optimum time for collecting leaves for the raw material is from the budding phase until the beginning of fruit ripening.  相似文献   
3.

Background  

Atrophy of the stomach mucosa is considered to be premalignant lesion for gastric cancer development; easy identification of this condition from a blood-sample would allow identifying the group of individuals at increased risk for cancer development.  相似文献   
4.

Background

Alzheimer disease (AD) is the major cause of dependency and disability in the elderly. Numerous studies have sought to achieve its prevention and/or management examining a role for modifiable risk factors, such as nutrition. This work aims to investigate the effects of food and/or nutrients in the management of AD at different stages.

Methods

Electronic databases were searched for clinical trials examining the effect of nutrient intervention in individuals with AD, compared with placebo, published up to 2014. The outcomes investigated were neuropsychological assessment scales, neuroimaging, and biomarkers. The Cochrane tool was employed to assess risk of bias. Pairwise meta-analyses were performed in a random-effect model by estimating the weighted mean differences with 95% confidence interval (CI) for each outcome measure. The Network meta-analysis was undertaken on cognitive outcome.

Results

Selected studies used antioxidants, B-vitamins, inositol, medium-chain triglyceride, omega-3, polymeric formulas, polypeptide, and vitamin D. AD outcome measurements were mainly restricted to cognitive state and functional abilities. Estimate treatment effects from pairwise meta-analyses showed large but nonsignificant effect in the supplementation with proline-rich polypeptide [weighted mean difference 6.93 (95% CI –3.04, 16.89); P = .17] and B-vitamins [weighted mean difference 0.52 (95% CI –0.05, 1.09); P = .07) on cognitive function measured by the Mini-Mental State Examination. The other nutrients supplementation did not show any significant effect on any outcome measures.

Conclusions

Isolated nutrient supplementations show no convincing evidence of providing a significant benefit on clinical manifestations or neuropathology of AD. During the initial stages of AD, nutrient supplementation did not show any effect when delivered individually, probably because of their synergistic function on brain, at different domains.  相似文献   
5.
PurposeDecreased plasma gastrin-17 (G-17), particularly after protein stimulation, is indicative of atrophy in the antral stomach mucosa. Available data on the value of this biomarker is inconclusive. Our study was aimed to evaluate the performance of the G-17 test in Caucasian and Asian patients for antral atrophy evaluation either in fasting state or after protein stimulation.Material/Methods241 dyspeptic patients aged 55 and above from Latvia (125), Lithuania (76) and Taiwan (40) were enrolled. G-17 levels were detected in plasma samples obtained either during fasting or after a protein-rich test meal. Levels <1pmol/L at fast and <5 pmol/L after stimulation were considered indicative of atrophy.ResultsThe sensitivity of the test was 15.8%, its specificity 88.7%, and the overall accuracy 83% in the fasting state, and 36.8, 86.5, and 82.6%, respectively, after stimulation. In the Caucasian subgroup, the corresponding figures were 15.4, 91.5, and 86.6% in the fasting state and 30.8, 92.6, 88.6% after stimulation; but for the Asian subgroup the corresponding figures were 16.7, 73.5, and 65% (fasting) and 50, 52.9, and 52.5% (stimulated).ConclusionsThe performance of G-17 was better after protein stimulation. G-17 was highly specific in the Caucasian, but not in the Asian subgroups. Still the low test sensitivity either at fast or following protein stimulation does not allow us to recommend it for wide screening purpose to diagnose antral atrophy.  相似文献   
6.
7.
A study of indium-incorporated copper selenide thin-film deposition on a glass substrate using the successive ionic adsorption and reaction method (SILAR) and the resulting properties is presented. The films were formed using these steps: selenization in the solution of diseleniumtetrathionate acid, treatment with copper(II/I) ions, incorporation of indium(III), and annealing in an inert nitrogen atmosphere. The elemental and phasal composition, as well as the morphological and optical properties of obtained films were determined. X-ray diffraction data showed a mixture of various compounds: Se, Cu0.87Se, In2Se3, and CuInSe2. The obtained films had a dendritic structure, agglomerated and not well-defined grains, and a film thickness of ~90 μm. The band gap values of copper selenide were 1.28–1.30 eV and increased after indium-incorporation and annealing. The optical properties of the formed films correspond to the optical properties of copper selenide and indium selenide semiconductors.  相似文献   
8.
Context The genus Hypericum (Hypericaceae) has attracted remarkable scientific interest as its members have yielded many bioactive compounds.

Objective The current study presents investigations on the accumulation of hypericin, pseudohypericin, hyperforin, adhyperforin, chlorogenic acid, neochlorogenic acid, caffeic acid, 2,4-dihydroxybenzoic acid, 13,118-biapigenin, hyperoside, isoquercitrin, quercitrin, quercetin, avicularin, rutin, (+)-catechin and (?)-epicatechin in seven Hypericum (Hypericaceae) species growing wild in Turkey, namely, H. aviculariifolium Jaup. and Spach subsp. aviculariifolium (Freyn and Bornm.) Robson var. albiflorum (endemic), H. bithynicum Boiss., H. calycinum L., H. cardiophyllum Boiss., H. elongatum L. subsp. microcalycinum (Boiss. and Heldr.) Robson, H. hirsutum L. and H. xylosteifolium (Spach) N. Robson.

Materials and methods The plant materials were collected at flowering period and dissected in different tissues. Air-dried plant material including stems, leaves and flowers was mechanically powdered with a laboratory mill and samples (0.1?g) were extracted in 10?mL of 100% methanol by ultrasonication at 40?°C for 30?min for HPLC-PDA analyses.

Results Accumulation levels of the investigated compounds varied greatly depending on species and plant part.

Discussion For the first time, the detailed chemical profiles of corresponding Turkish Hypericum species were reported and the results were discussed from a phytochemical point of view.

Conclusions The present data have importance in evaluation of plant resources of Hypericum genus in selecting the new potential sources of bioactive compounds.  相似文献   
9.
A study of altering the conductive properties of wool fibers by applying copper selenide is presented. The researched modification of wool fibers was based on a two-stage adsorption-diffusion process. X-ray diffraction, scanning electron microscope, energy-dispersive X-ray spectrum, and Fourier transform infrared spectroscopy were performed to evaluate the morphological and physical characteristics of all CuxSe-coated wool fibers. X-ray diffraction (XRD) data showed a single, Cu0.87Se (klockmannite), crystalline phase present, while Atomic Absorption Spectroscopy (AAS) and Energy Dispersive X-ray (EDX) analyses showed that the concentrations of Cu and Se in copper selenide coatings depend on the number of wool fiber treatment cycles. It was determined that a dense layer of CuxSe grows through a nucleation mechanism followed by particle growth to fill out the complete surface. It was found that the conductivity of the coated wool fibers depends on the quality and density of the copper selenide coating, thus the resistance of electrically impermeable wool fibers can be reduced to 100 Ω by increasing the number of treatment cycles.  相似文献   
10.
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