首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   35篇
  免费   2篇
化学   22篇
力学   1篇
数学   3篇
物理学   11篇
  2022年   2篇
  2020年   2篇
  2017年   1篇
  2016年   1篇
  2014年   2篇
  2013年   3篇
  2012年   2篇
  2011年   5篇
  2010年   1篇
  2009年   4篇
  2008年   1篇
  2007年   1篇
  2003年   1篇
  2002年   1篇
  2000年   1篇
  1997年   1篇
  1995年   1篇
  1993年   1篇
  1984年   1篇
  1982年   1篇
  1980年   2篇
  1977年   1篇
  1970年   1篇
排序方式: 共有37条查询结果,搜索用时 15 毫秒
1.
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatographic method has been developed for determination of a new antiamoebic drug, satranidazole,...  相似文献   
2.
The muscle metabolism of at-rest patients with varying degrees of postpolio residual paralysis (PPRP) was studied and compared with that of controls using in vivo phosphorus magnetic resonance spectroscopy. The phosphocreatine (PCr)/inorganic phosphate (Pi) and PCr/adenosine triphosphate ratios were lower in patients than in controls. Reduction in PCr/Pi suggests abnormalities in oxidative phosphorylation. A significant increase was observed in the phosphomonoester/PCr ratio in patients, indicating the accumulation of intermediary compounds of the glycolytic pathway. Furthermore, the phosphodiester/PCr ratio was also significantly increased in patients. In general, the observed changes in metabolite ratios were found to be related to the degree of residual paralysis, suggesting that metabolic changes are secondary to chronic neurogenic processes. These metabolic alterations appear to be the possible cause of energy deficit and underlying muscle fatigue in PPRP patients. The present results provide an insight into the metabolic impairment and degree of muscle damage in patients with PPRP.  相似文献   
3.
Propolis, also known as bee-glue, is a resinous substance produced by honeybees from materials collected from plants they visit. It contains mixtures of wax and bee enzymes and is used by bees as a building material in their hives and by humans for different purposes in traditional healthcare practices. Although the composition of propolis has been shown to depend on its geographic location, climatic zone, and local flora; two largely studied types of propolis: (i) New Zealand and (ii) Brazilian green propolis have been shown to possess Caffeic Acid Phenethyl Ester (CAPE) and Artepillin C (ARC) as the main bioactive constituents, respectively. We have earlier reported that CAPE and ARC possess anticancer activities, mediated by abrogation of mortalin-p53 complex and reactivation of p53 tumor suppressor function. Like CAPE, Artepillin C (ARC) and the supercritical extract of green propolis (GPSE) showed potent anticancer activity. In this study, we recruited low doses of GPSE and ARC (that did not affect either cancer cell proliferation or migration) to investigate their antistress potential using in vitro cell based assays. We report that both GPSE and ARC have the capability to disaggregate metal- and heat-induced aggregated proteins. Metal-induced aggregation of GFP was reduced by fourfold in GPSE- as well as ARC-treated cells. Similarly, whereas heat-induced misfolding of luciferase protein showed 80% loss of activity, the cells treated with either GPSE or ARC showed 60–80% recovery. Furthermore, we demonstrate their pro-hypoxia (marked by the upregulation of HIF-1α) and neuro-differentiation (marked by differentiation morphology and upregulation of expression of GFAP, β-tubulin III, and MAP2). Both GPSE and ARC also offered significant protection against oxidative stress and, hence, may be useful in the treatment of old age-related brain pathologies.  相似文献   
4.
A facile method for the construction of an immunoconjugate which displays targeting ligands, such as antibody fragments, with a high density is reported. For this purpose, we synthesized a novel trifunctional crosslinking reagent. By the use of this reagent, ligands targeting the specific cell can be displayed on the surface of the drug carrier with a high density. In this study, we display HER2 (human epidermal growth‐factor receptor‐2) binding ligands on branched polyethylenimine (PEI), which can form polyplexes with plasmid DNA. Kinetic analysis of the binding to the extracellular domain of HER2 show the PEI displaying a high density of ligands binds to the target more strongly compared to the PEI displaying ligands at a low density. The increased density of HER2 ligands displayed on the gene carrier contributes to the improved transfection efficiency. This approach can be applied to other drug delivery systems, including liposome, micelle, and so on.  相似文献   
5.
V K Gupta  A Wadhwa  J D Anand 《Pramana》1995,45(2):195-208
We evaluate the emissivity rates for d-decay and s-decay by exactly solving the angular integrals involved and without assuming the degeneracy of electrons. We have also studied the effects of QCD coupling constant as well as the s-quark mass on the emissivity rates. We find that these parameters are important in determining the threshold and extinction densities for d- and s-decays.  相似文献   
6.
7.
Trigonelline (TR), 4-hydroxyisoleucine (4-HI), and diosgenin (DG) are the main bioactives of the purified standardized extract of the popular plant Trigonella foenum-graecum L. (TFG), and it has been proven effective for the treatment of various diseases. However, to the best of our knowledge, no study has investigated the pharmacokinetic parameters of purified standardized T. foenum-graecum extract in normal and diabetic Wistar rats. The present study has developed and validated a rapid, reliable, and sensitive simultaneous ultra-performance liquid chromatography MS method to estimate these bioactives. The chromatographic separation was achieved using methanol, acetonitrile, and 0.1% formic acid with the ideal gradient flow system on a BEH Shield RP 18 column. A positive electrospray ionization mode was selected to estimate m/z values of TR (138.14 > 94.63), 4-HI (148.19 > 74.08), and DG (415.54 > 271.33). The method was robust and reproducible over the linearity range of 60–5000, 6–5000, and 15–5000 ng/mL for TR, 4-HI, and DG, respectively. Using this novel validated method, we investigated the pharmacokinetic parameters of bioactives using Phoenix WinNonlin version 8.0 (Certera) in normal and diabetic rats. The assay was successfully applied for the estimation of pharmacokinetic parameters using noncompartmental analysis. This investigation shows that the absorption rate increased, whereas distribution and elimination processes slowed down in diabetic rats compared with normal rats.  相似文献   
8.
This paper is devoted to the study of dominant operators with an emphasis on their spectral properties. In particular the equation (T–)f() x (T a dominant or hyponormal operator on the Hilbert space ,x andf a function from the open setU to ) is investigated in an effort to discover necessary and/or sufficient conditions for the analyticity off.Supported in part by the National Science Foundation.  相似文献   
9.
10.
A modified protocol for diastereoselective synthesis of differently substituted trans-2,3-dihydrofuro[3,2-c]coumarins is developed via, a one-pot multicomoponent reaction starting from aromatic aldehydes, 4-hydroxycoumarin, and α-tosyloxyacetophenones with pyridine and triethylamine as catalysts. The developed protocol provides a better alternative to the existing methods as it involves utilization of α-tosyloxyacetophenones that may be generated in situ from acetophenones and [hydroxyl(tosyloxy)iodo]benzene (HTIB, Koser's reagent), avoiding the use of α-haloacetophenones.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号