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排序方式: 共有316条查询结果,搜索用时 15 毫秒
81.
Imran Ahmad Khan Musaddique Hussain Shahzada Khurram Syed Malik Saadullah Ali M. Alqahtani Taha Alqahtani Afaf A. Aldahish Saeed Asiri Ling-Hui Zeng 《Molecules (Basel, Switzerland)》2022,27(1)
Plumeria rubra (L.) is a traditional folkloric medicinal herb used to treat cardiovascular disorders. The present investigation was methodically planned to investigate the pharmacological foundations for the therapeutic effectiveness of P. rubra in cardiovascular illnesses and its underlying mechanisms. Ex vivo vaso-relaxant effects of crude leaf extract of P. rubra were observed in rabbit aorta ring preparations. Hypotensive effects were measured using pressure and force transducers connected to the Power Lab data acquisition system. Furthermore, P. rubra displayed cardioprotective properties in rabbits when they were exposed to adrenaline-induced myocardial infarction. In comparison to the intoxicated group, the myocardial infarction model showed decreased troponin levels, CK-MB, LDH, ALT, ALP, AST, and CRP, as well as necrosis, apoptosis, oedema, and inflammatory cell enrollment. P. rubra has revealed good antioxidant properties and prolonged the noradrenaline intoxicated platelet adhesion. Its anticoagulant, vasorelaxant, and cardioprotective effects in both in vivo and ex vivo investigations are enabled by blocking L-type calcium channels, lowering adrenaline, induced oxidative stress, and tissue tear, justifying its therapeutic utility in cardiovascular disorders. 相似文献
82.
M. Khurram Wadee M. Ahmer Wadee 《Journal of the mechanics and physics of solids》2007,55(5):1086-1102
The behaviour of tubes under conditions of pure bending is investigated for the cases where the material of which they are constructed is either orthotropic or of various Poisson's ratios. Large deflections and moderate nonlinear strains are considered and the modelling incorporates Timoshenko beam theory thereby allowing non-zero shear strains to develop. This in turn makes axially inhomogeneous deformation of the cross-section possible and, in particular, the compressed side can develop wrinkling. Numerical solutions are presented for various material types and tube dimensions and some interesting phenomena, such as mode interaction and jumping, are demonstrated. 相似文献
83.
Lipid-lowering effects of ethyl 2-phenacyl-3-aryl-1H-pyrrole- 4-carboxylates in rodents 总被引:3,自引:0,他引:3
Holub JM O'Toole-Colin K Getzel A Argenti A Evans MA Smith DC Dalglish GA Rifat S Wilson DL Taylor BM Miott U Glersaye J Lam KS McCranor BJ Berkowitz JD Miller RB Lukens JR Krumpe K Gupton JT Burnham BS 《Molecules (Basel, Switzerland)》2004,9(3):134-157
A series of substituted 2-phenacyl-3-phenyl-1H-pyrrole-4-carboxylates were prepared from substituted acetophenones in 6 steps. The final condensations between a chloroenal and an aminoketone were carried out under neutral conditions in parallel to yield the series listed below. Selected pyrrole derivatives proved to be potent hypolipidemic agents lowering serum triglyceride concentrations in CF-1 male mice after 14 days of I.P. administration. One agent orally lowered serum cholesterol in Sprague-Dawley male rats at 2mg/kg/day after 14 days. The agents demonstrated a lowering of mouse serum LDL- cholesterol levels and selected compounds showed an elevation of serum HDL-cholesterol levels. The cholesterol concentrations in the liver were raised while the cholesterol and triglyceride contents of the aorta were significantly lowered by the selected trisubstituted pyrrole. 相似文献
84.
Bilal Akram Dr. Wenxiong Shi Hao Zhang Shaheed Ullah Muhammad Khurram Prof. Dr. Xun Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8575-8579
A single-step solution-based strategy is used to obtain 2D Janus-like free-standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D-to-1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM-CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM-CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications. 相似文献
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We present theoretical design for omnidirectional reflector (ODR) using one-dimensional photonic heterostructure. With the help of transfer matrix approach, we present a simple design to achieve the ODR at a desired wavelength range of interest using a high refractive index material which is dispersive at that wavelength range. Taking material combinations of SiO2 and GaSb as low and high index medium a perfect ODR is designed in the 1480–1680 nm wavelength region. 相似文献
90.