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Role of arachidonic acid in hyposmotic membrane stretch-induced increase in calcium-activated potassium currents in gastric myocytes

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Acta Pharmacologica Sinica 2005年第10期26卷 1233-1242页

作者： Meng YANG~2, Xing-lan LI~3, Hui-ying XU~3, Jia-bin SUN~3, Bin MEI~4, Hai-feng ZHENG~3, Lian-hua PIAO~3, De-gang XING~3 Zhai-liu LI~3, Wen-xie XU~(2,5) ~2 Department of Physiology, Shanghai Jiaotong university school of Medicine, Shanghai 200030 ~3 Department of Physiology Yanbian university College of Medicine Yanji 133000 ~4 East china normal university school of Life Science, Shanghai 200062, china Department of Physiology Shanghai Jiaotong University School of Medicine Shanghai China Department of Physiology Yanbian University College of Medicine Yanji China East china normal university school of Life Science Shanghai China

Aim: To study effects of arachidonic acid （AA） and its metabolites on the hyposmotic membrane stretch-induced increase in calcium-activated potassium currents (IKCa) in gastric myocytes. Methods: Membrane currents were recorded by using a conventional whole cell patch-clamp technique in gastric myocytes isolated with collagenase. Results: Hyposmotic membrane stretch and AA increased both IK（Ca）and spontaneous transient outward currents significantly. Exogenous AA could potentiate the hyposmotic membrane stretch-induced increase in IK（Ca）The hyposmotic membrane stretch-induced increase inK（Ca）was significantly suppressed by dimethyleicosadienoic acid （100 μmol/L in pipette solution）, an inhibitor of phospholipase A2. Nordihydroguaiaretic acid, a lipoxygenase inhibitor, significantly suppressed AA and hyposmotic membrane stretch-induced increases in IK（Ca）. External calcium-free or gadolinium chloride, a blocker of stretch-activated channels, blocked the AA-induced increase in IK（Ca）significantly, but it was not blocked by nicardipine, an L-type calcium channel blocker. Ryanodine, a calcium-induced calcium release agonist, completely blocked the AA-induced increase inK（Ca）; however, heparin, a potent inhibitor of inositol triphosphate receptor, did not block the AA-induced increase in IK（Ca）. Conclusion: Hyposmotic membrane stretch may activate phospholipase A2, which hydrolyzes membrane phospholipids to ultimately produce AA; AA as a second messenger mediates Ca2+influx, which triggers Ca2+-induced Ca2+release and elicits activation of IK（Ca）in gastric antral circular myocytes of the guinea pig.

关键词： gastric myocyte arachidonic acid hyposmotic membrane stretch calcium-activated potassium current.

On the error term in Weyl’s law for the Heisenberg manifolds (Ⅱ)

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Science china Mathematics 2009年第5期52卷 857-874页

作者： ZHAI WenGuang school of Mathematical Sciences, Shandong normal university, Jinan 250014, china school of Mathematical Sciences Shandong Normal University Jinan China

In this paper we study the mean square of the error term in the Weyl's law of an irrational (2l + 1)-dimensional Heisenberg manifold. An asymptotic formula is established.

关键词： Heisenberg manifold Weyl’s law error term mean square

Alterations in circadian rhythms of melaton in and cortisol in patients with bronchial asthma

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Acta Pharmacologica Sinica 2004年第5期25卷 109-114页

作者： Guang-he FEI2,3, Rong-yu LIU3,4, Zhi-hong ZHANG3, Jiang-ning ZHOU2,32school of Life Science, university of Science and Technology of china, Hefei 230026, china 3Pulmonary Department, First Affiliated Hospital, Anhui medical university, Hefei 230022, china school of Life Science University of Science and Technology of China Hefei 230026 Pulmonary Department First Affiliated Hospital Anhui Medical University Hefei 230022 Pulmonary Department First Affiliated Hospital Anhui Medical University Hefei 230026

AIM: To investigate the possible relationships between alterations in circadian rhythm of melatonin, cortisol andbronchial asthma. METHODS: Salivary melatonin and cortisol were measured simultaneously by radioimmunoas-say in 10 mild intermittent or persistent patients, 11 moderate-to-severe persistent asthma patients, and 15 controlsubjects. Twelve salivary samples were collected in a series during a 24-h period in each subject. RESULTS: Theresults showed overall lower levels of salivary melatonin in asthma patients compared with control subject(P<0.01). The amplitude, peak-level, and baseline of salivary melatonin were significantly lower in mild intermit-tent or persistent (P<0.01, P<0.05) and moderate-to-severe persistent asthma patients (P<0.01) compared withcontrol group. The 24-h mean level of salivary cortisol was greatly lower and the acrophase was markedly delayedin patients with mild intermittent or persistent asthma (P<0.01) and moderate-to-severe persistent asthma (P<0.05, P<0.01) compared with control subject. CONCLUSION: Disordered circadian rhythms of salivary melato-nin and cortisol were found in asthma patients, which may be involved in the pathogenesis of bronchial asthma.

关键词： melatonin asthma circadian rhythm glucocorticoids human saliva

Multipliers and Herz type spaces

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Science china Mathematics 2008年第10期51卷 1919-1936页

作者： LU ShanZhen school of Mathematical Sciences, Beijing normal university, Beijing 100875, china school of Mathematical Sciences Beijing Normal University Beijing China

Hrmander condition for boundedness of multiplier operators will be replaced by a weaker condition described by certain weighted or non-weighted Herz spaces. Some results on boundedness of multiplier operators are then established. As direct corollaries of main theorems in this paper, several celebrated results on boundedness of multiplier operators will be improved or deduced.

关键词： multiplier Herz space Herz type Hardy space 42B15 42B30 42B35

Hausdorff measures of the image, graph and level set of bifractional Brownian motion

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Science china Mathematics 2010年第11期53卷 2973-2992页

作者： LUAN NaNa school of Mathematical Sciences, Beijing normal university, Beijing 100875, china school of Mathematical Sciences Beijing Normal University Beijing China

Let BH,K = {BH,K(t), t ∈ R+} be a bifractional Brownian motion in Rd. This process is a selfsimilar Gaussian process depending on two parameters H and K and it constitutes a natural generalization of fractional Brownian motion (which is obtained for K = 1). The exact Hausdorff measures of the image, graph and the level set of BH,K are investigated. The results extend the corresponding results proved by Talagrand and Xiao for fractional Brownian motion.

关键词： bifractional Brownian motion self-similar Gaussian processes image graph level set local time Hausdorff dimension Hausdorff measure

On the Symmetry Classes of Functions

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Wuhan university Journal of Natural Sciences 2005年第5期10卷 813-816页

作者： ZHU Ping~1,2, FAN Yun~3 1. school of Mathematics and Statistics, Wuhan university, Wuhan 430072, Hubei, china 2. school of Science, Beijing university of Posts and Telecommunications, Beijing 100876, china 3. school of Mathematics and Statistics, Huazhong normal university, Wuhan 430079, Hubei, china school of Mathematics and Statistics Wuhan University Wuhan Hubei China school of Science Beijing University of Posts and Telecommunications Beijing China school of Mathematics and Statistics Huazhong Normal University Wuhan Hubei China

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

Optical waveguides in LiNbO_3 and stoichiometric LiNbO_3 crystals by proton exchange

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing College of Physics and Engineering, Qufu normal university, Qufu 273165, china school of Physics and Microelectronics, Shandong university, Jinan 250100, china College of Physics and Engineering Qufu Normal University Qufu China school of Physics and Microelectronics Shandong University Jinan China

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

Propagation of liquid surface waves over finite graphene structured arrays of cylinders

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Theoretical & Applied Mechanics Letters 2011年第5期1卷 73-76页

作者： Xuemei Liu,1,2 Yong Wei,1 Sheng Li,1 Yousheng Xu,1,Detang Lu,3 and Boming Yu 4 1) Department of Physics,Zhejiang normal university,Jinhua 321004,Zhejiang,china 2) hangzhou No.14 Middle school,hangzhou 310006,china 3) Department of Modern Mechanics,university of Science and Technology of china,Hefei 230027,china 4) school of Physics,Huazhong university of Science and Technology,Wuahn 430074,china Department of Physics Zhejiang Normal University Jinhua 321004 Zhejiang China hangzhou No. 14 Middle school Hangzhou 310006 China Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China school of Physics Huazhong University of Science and Technology Wuahn 430074 China

Based on the multiple scattering method,this paper investigates a benchmark problem of the propagation of liquid surface waves over finite graphene (or honeycomb) structured arrays of *** the graphene structured array with the square structured and with triangle structured arrays,it finds that the finite graphene structure can produce more complete band gaps than the other finite structures,and the finite graphene structure has less localized ability than the other finite structures.

关键词： propagation liquid surface wave graphene structured array multiple scattering method

Role of melatonin in Alzheimer-like neurodegeneration

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Acta Pharmacologica Sinica 2006年第1期27卷 41-49页

作者： Jian-zhi WANG~(2,4) Ze-fen WANG~(2,3)2 Pathophysiology Department,Key Laboratory of Neurological Diseases of Hubei Province,Tongji medical school,Huazhong university of Science and Technology,Wuhan 430030,china 3 Department of Physiology,medical College,Wuhan university Wuhan 430071,china Pathophysiology Department Key Laboratory of Neurological Diseases of Hubei Province Tongji Medical School Huazhong University of Science and Technology Wuhan China Department of Physiology Medical College Wuhan University Wuhan China

Alzheimer disease (AD),an age-related neurodegenerative disorder with progres-sive loss of memory and deterioration of comprehensive cognition,is character-ized by extracellular senile plaques of aggregated β-amyloid (Aβ),and intracellularneurofibrillary tangles that contain hyperphosphorylated tau *** showed that melatonin,an indoleamine secreted by the pineal gland,mayplay an important role in aging and AD as an antioxidant and *** decreases during aging and patients with AD have a more profoundreduction in this *** from clinical trials indicate that melatonin supple-mentation improves sleep,ameliorates sundowning,and slows down the progres-sion of cognitive impairment in Alzheimer's *** efficiently pro-tects neuronal cells from Aβ-mediated toxicity via antioxidant and anti-amyloidproperties:it not only inhibits Aβ generation,but also arrests the formation ofamyloid fibrils by a structure-dependent interaction with Aβ.Our recent studieshave demonstrated that melatonin efficiently attenuates Alzheimer-like *** the exact mechanism is still not fully understood,a direct regulatory influence of melatonin on the activities of protein kinases andprotein phosphatases is ***,melatonin also plays a role inprotecting cholinergic neurons and in ***,the neuroprotectiveeffects of melatonin and the underlying mechanisms by which it exerts its effectsare *** capacity of melatonin to prevent or ameliorate tau and Aβpathology further enhances its potential in the prevention or treatment of AD.

关键词： Alzheimer disease melatonin tau,beta amyloid