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排序方式: 共有897条查询结果,搜索用时 15 毫秒
891.
M. Surya Sandeep V. Sridhar Y. Puneeth P. Ravindra Babu 《Drug development and industrial pharmacy》2014,40(10):1371-1377
The aim of this study was to investigate the effect of naringenin on the pharmacokinetics (PK) of felodipine in rats and membrane permeability across rat everted gut sacs in vitro. Rats were simultaneously co-administered with felodipine 10?mg/kg, p.o. and naringenin (25, 50 and 100?mg/kg, p.o.) for 15 consecutive days. Rats of the control groups received the corresponding volume of vehicle. Blood samples were withdrawn from retro-orbital plexus on first day in single dose PK study (SDS) and on 15th day in multiple dosing PK study (MDS). The PK parameters were calculated using Thermo kinetica. The co-administration of naringenin significantly elevated the Cmax and increased the AUCtotal of felodipine in dose-dependent manner. The Cmax of felodipine was increased from 173.25?±?14.65 to 275.61?±?44.62 and 223.26?±?26.35 to 561.32?±?62.53?ng/mL in SDS and MDS, respectively, at the dose of naringenin 100?mg/kg. The AUCtotal of felodipine was significantly (p?0.001) increased from 2050.48?±?60.57 to 3650.22?±?78.61 and 3276.51?±?325.61 to 7265.25?±?536.11 (ng/mL/h) in SDS and MDS, respectively. The permeability of felodipine was increased in presence of naringenin and ritonavir (standard P-glycoprotein (P-gp) and Cytochrome P450 (CYP)3A4 inhibitor). Felodipine is a substrate of CYP3A4, and naringenin was reported to be a modulator of P-gp and CYP3A4. These results suggest that naringenin significantly increased the Cmax and AUC of felodipine is due to P-gp and CYP3A4 inhibition. 相似文献
892.
Dr. Eric K. W. Tam Dr. Tuan Minh Nguyen Cheryl Z. H. Lim Puay Leng Lee Zhimei Li Xia Jiang Dr. Sridhar Santhanakrishnan Tiong Wei Tan Yi Ling Goh Sze Yue Wong Haiyan Yang Esther H. Q. Ong Dr. Jeffrey Hill Dr. Qiang Yu Prof. Christina L. L. Chai 《ChemMedChem》2015,10(1):173-182
3‐Deazaneplanocin A (DzNep) is a potential epigenetic drug for the treatment of various cancers. DzNep has been reported to deplete histone methylations, including oncogenic EZH2 complex, giving rise to epigenetic modifications that reactivate many silenced tumor suppressors in cancer cells. Despite its promise as an anticancer drug, little is known about the structure–activity relationships of DzNep in the context of epigenetic modifications and apoptosis induction. In this study, a number of analogues of DzNep were examined for DzNep‐like ability to induce synergistic apoptosis in cancer cells in combination with trichostatin A, a known histone deacetylase (HDAC) inhibitor. The structure–activity relationship data thus obtained provide valuable information on the structural requirements for biological activity. The studies identified three compounds that show similar activities to DzNep. Two of these compounds show good pharmacokinetics and safety profiles. Attempts to correlate the observed synergistic apoptotic activities with measured S‐adenosylhomocysteine hydrolase (SAHH) inhibitory activities suggest that the apoptotic activity of DzNep might not be directly due to its inhibition of SAHH. 相似文献
893.
S. Meenakshi A. Manokaran S. D. Bhat A. K. Sahu P. Sridhar S. Pitchumani 《Fuel Cells》2014,14(6):842-852
Hybrid membranes are prepared from fluoro and non‐fluoro polymer membrane matrices with mesoporous and microporous inorganic materials. Nafion‐Si‐MSU‐F, Nafion‐Al‐MCM‐41, and zeolite 4A‐SPEEK‐MSA hybrid membranes are fabricated by solution casting method. The structural properties of the membranes are characterized using FE‐SEM and AFM techniques. Ion exchange capacity, sorption, proton conductivity, and thermal stability for the membranes have been extensively investigated. Ethanol permeability measurements for the membranes are performed using electrochemical as well as diffusion cell method. Among the membranes that are tested in direct ethanol fuel cells (DEFCs), Nafion‐Al‐MCM‐41 hybrid membrane delivered the highest peak power‐density of 44 mW cm–2 at 70 °C. 相似文献
894.
Bärlocher F Guenzel K Sridhar KR Duffy SJ 《The Science of the total environment》2011,409(9):1651-1657
We measured the removal of 4-n-nonylphenol (between 50 and 500 μg L−1) from an aqueous solution with or without linden and oak leaf disks. More 4-n-NP was removed when the leaves were first exposed for 3 weeks in a stream, which allowed colonization by aquatic hyphomycetes. The response of fungal sporulation rates from beech, linden, maple and oak leaves to increasing levels of 4-n-NP was complex. Linear regressions were non-significant, arguing against a no-threshold model. The response at the lowest concentration (50 μg L−1) was between 7% (beech) and 67% (maple) higher than in the absence of 4-n-NP, however, the difference was not significant. The number of sporulating species of aquatic hyphomycetes was significantly higher at the lowest concentration than in the control treatment without 4-n-NP. The composition of the fungal community was affected by leaf species but not by 4-n-NP concentration. The results suggest the presence of a weak hormeotic effect. The known ability of aquatic hyphomycetes and other fungi to degrade nonylphenols and related substances, combined with fungal resilience in their presence, makes decaying leaves potential candidates for bioremediation. 相似文献
895.
Solar Air Heater is a simple, cheap and most widely used for various applications such as textile industries, agricultural, desalination and space heating. Generally collectors are tilted so as to absorb maximum radiation, so it is necessary to calculate the optimum tilt angle to maximize the solar radiation falling on the collector area to gain maximum useful energy. The maximum solar radiation can be collected by using a tracking mechanism. Tracking systems are expensive and complicated in construction. The working operation of solar integrated tracking system is difficult. This paper presents the mechanism of evaluating the overall heat transfer coefficient of the solar air-heater at variable intensities and inlet velocities. The experimental setup is integrated with blower at inlet to the solar air heater in order to pump air at different velocities. The work focus on comparative study of solar air heating system for different tilt angles ranging from 250 to 600 and determines the overall heat transfer coefficient so as to find the optimum tilt angle of a solar flat plate collector. 相似文献
896.
In this paper, the investigation of a novel compact 2 × 2, 2 × 1, and 1 × 1 Ultra-Wide Band (UWB) based Multiple-Input Multiple-Output (MIMO) antenna with Defected Ground Structure (DGS) is employed. The proposed Electromagnetic Radiation Structures (ERS) is composed of multiple radiating elements. These MIMO antennas are designed and analyzed with and without DGS. The feeding is introduced by a microstrip-fed line to significantly moderate the radiating structure’s overall size, which is 60 × 40 × 1 mm. The high directivity and divergence characteristics are attained by introducing the microstrip-fed lines perpendicular to each other. And the projected MIMO antenna structures are compared with others by using parameters like Return Loss (RL), Voltage Standing Wave Ratio (VSWR), Radiation Pattern (RP), radiation efficiency, and directivity. The same MIMO set-up is redesigned with DGS, and the resultant parameters are compared. Finally, the Multiple Input and Multiple Output Radiating Structures with and without DGS are compared for result considerations like RL, VSWR, RP, radiation efficiency, and directivity. This projected antenna displays an omnidirectional RP with moderate gain, which is highly recommended for human healthcare applications. By introducing the defected ground structure in bottom layer the lower cut-off frequencies of 2.3, 4.5 and 6.0 GHz are achieved with few biological effects on radio propagation in human body communications. The proposed design covers numerous well-known wireless standards, along with dual-function DGS slots, and it can be easily integrated into Wireless Body Area Networks (WBAN) in medical applications. This WBAN links the autonomous nodes that may be situated either in the clothes, on-body or beneath the skin of a person. This system typically advances the complete human body and the inter-connected nodes through a wireless communication channel. 相似文献
897.
Sridhar M. Melwin Jagadeesh Ravichandran M. Meignanamoorthy M. Mohanavel V. 《SILICON》2022,14(11):5877-5886
Silicon - In this work Copper based composites were synthesized from Cu and SiC powders using Powder Metallurgy (PM) technique. The composition of the composites are Cu, Cu-5 wt% SiC,... 相似文献