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排序方式: 共有461条查询结果,搜索用时 562 毫秒
91.
Tahira Foyzun Abdullah Al Mahmud Md. Salim Ahammed Md. Imran Nur Manik Md. Kamrul Hasan KM Monirul Islam Simin Sobnom Lopa Md. Yusuf Al-Amin Kushal Biswas Mst. Rejina Afrin AHM Khurshid Alam Golam Sadik 《Molecules (Basel, Switzerland)》2022,27(3)
Neurotoxicity is a serious health problem of patients chronically exposed to arsenic. There is no specific treatment of this problem. Oxidative stress has been implicated in the pathological process of neurotoxicity. Polyphenolics have proven antioxidant activity, thereby offering protection against oxidative stress. In this study, we have isolated the polyphenolics from Acacia nilotica and investigated its effect against arsenic-induced neurotoxicity and oxidative stress in mice. Acacia nilotica polyphenolics prepared from column chromatography of the crude methanol extract using diaion resin contained a phenolic content of 452.185 ± 7.879 mg gallic acid equivalent/gm of sample and flavonoid content of 200.075 ± 0.755 mg catechin equivalent/gm of sample. The polyphenolics exhibited potent antioxidant activity with respect to free radical scavenging ability, total antioxidant activity and inhibition of lipid peroxidation. Administration of arsenic in mice showed a reduction of acetylcholinesterase activity in the brain which was counteracted by Acacia nilotica polyphenolics. Similarly, elevation of lipid peroxidation and depletion of glutathione in the brain of mice was effectively restored to normal level by Acacia nilotica polyphenolics. Gallic acid methyl ester, catechin and catechin-7-gallate were identified in the polyphenolics as the major active compounds. These results suggest that Acacia nilotica polyphenolics due to its strong antioxidant potential might be effective in the management of arsenic induced neurotoxicity. 相似文献
92.
2 has been used for smoothing of rough InAs, InP, and InSb surfaces, prepared by argon ion beam etching (IBE). The evolution
of the surface roughness and morphology has been studied by atomic force microscopy (AFM) as a function of the N2 RIBE process parameters (ion beam energy, ion beam angle of incidence, and ion dose). A drastic improvement of the surface
roughness has been observed for ion beam angles near normal incidence and larger than 70° with increasing ion doses. By using
this technique, the initial root-mean-square (rms) roughness of, e.g., InSb of about 40 nm could be decreased to about 1 nm.
Received: 20 March 1998/Accepted: 24 March 1998 相似文献
93.
T. Benter M. Liesner V. Sauerland R. N. Schindler 《Analytical and bioanalytical chemistry》1995,351(6):489-492
One- and two-colour photoionisation spectra for NO2 have been investigated using a time of flight mass spectrometer as detector to find the most efficient REMPI process for analytical applications. Two different inlet systems have been employed: a pulsed supersonic jet expansion stage and a flow reactor. Selective and sensitive mass spectrometric determinations of free NO2 have been possible even in the presence of high concentrations of organic nitrates, HNO3 and other NO2 precursors. Employing two-colour (1+1′+1) excitation using a concentration of HNO3≤5·1014 molecules/cm3 a detection limit of 5·1011 molecules/cm3 has been found for NO2 whereas in the absence of HNO3 a detection limit of 5·1010 molecules/cm3 is reported. 相似文献
94.
95.
Johannes Georg Schindler Maria M. Schindler 《Fresenius' Journal of Analytical Chemistry》1989,335(6):553-556
Summary Ion-selective sensors with tubular carrier-PVC membranes and a further developed solid-state cement contact are described. As a component of a sensor's flow channel and an interposed segment, each membrane is absolutely tight diffusion-welded between two PVC tube interfaces. Multiple measuring systems including these oxygen-independent, sturdy, maintenance-free sensors with stable measuring properties have already stood the tests under clinical conditions in the electrochemically-controlled hemodialysis. 相似文献
96.
Christian Schindler 《Foundations of Physics》1991,21(4):483-498
Aquantum logic (-orthocomplete orthomodular poset L with a convex, unital, and separating set of states) is said to have theexistence property if the expectation functionals onlin() associated with the bounded observables of L form a vector space. Classical quantum logics as well as the Hilbert space logics of traditional quantum mechanics have this property. We show that, if a quantum logic satisfies certain conditions in addition to having property E, then the number of its blocks (maximal classical subsystems) must either be one (classical logics) or uncountable (as in Hilbert space logics).Part of this work was done while the author was a visitor at the Department of Mathematics and Computer Science of the University of Denver, Denver, Colorado. 相似文献
97.
It is shown that the cone of positive normal functionals on a hypergraphA may be substantially larger than the cone of positive weights onA. For a semiclassical hypergraphA the two cones coincide if and only if the number of edges ofA of cardinality 2 is finite. This disproves an earlier statement of T. A. Cook. 相似文献
98.
Adler J Becker JJ Blaylock GT Bolton T Brown JS Bunnell KO Burnett TH Cassell RE Coffman D Cook V Coward DH Dorfan DE Dubois GP Duncan AL Eigen G Einsweiler KF Eisenstein BI Freese T Gladding G Grab C Grancagnolo F Hamilton RP Hauser J Heusch CA Hitlin DG Izen JM Köpke L Li A Lockman WS Mallik U Matthews CG Mir R Mockett PM Mozley RF Nemati B Odian A Parrish L Partridge R Perrier J Pitman D Plaetzer SA Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Simopoulos C 《Physical review letters》1988,60(2):89-92
99.
Bolton T Brown JS Bunnell KO Burchell M Burnett TH Cassell RE Coffman D Coward DH Coyle P DeJongh F Drinkard J Dubois GP Eigen G Eisenstein BI Freese T Gatto C Gladding G Heusch CA Hitlin DG Izen JM Kim PC Labs J Li A Lockman WS Mallik U Matthews CG Mir R Mockett PM Odian A Parrish L Pitman D Richman JD Sadrozinski HF Scarlatella M Schalk TL Schindler RH Seiden A Stockdale IE Toki W Tripsas B Wang MZ Weinstein AJ Weseler S Willutzki HJ Wisniewski WJ Xu R Zhu Y 《Physical review letters》1992,69(9):1328-1331
100.
Coffman D DeJongh F Dubois GP Eigen G Hitlin DG Matthews CG Richman J Weinstein AJ Wisniewski WJ Zhu Y Bolton T Bunnell KO Cassell RE Coward DH Kim PC Labs J Odian A Pitman D Schindler RH Toki W Wasserbaech S Drinkard JJ Gatto C Heusch CA Lockman WS Sadrozinski HF Scarlatella M Schalk TL Seiden A Xu R Eisenstein BI Freese T Gladding G Izen JM Stockdale IE Tripsas B Mallik U Wang MZ Brown JS Burnett TH Li AD Mir R Mockett PM Nemati B Parrish L Willutzki H 《Physical review letters》1992,68(3):282-285