检索结果-南通市图书馆

Regulating role of acetylcholine and its antagonists in inward rectified K^+ channels from guard cell protoplasts of Vicia faba

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2000年第2期43卷 217-224页

作者：冷强花宝光郭玉海娄成后 1. Plant Physiology Laboratory Chinese Agricultural University 100094 Beijing China 2. Plant Physiology and Biochemistry Laboratory Beijing Agricultural College 102206 Beijing China

The inward rectified potassium current of Vicia faba guard cell protoplasts treated with acetylcholine (ACh) or the antagonists of its receptors were recorded by employing the patch clamp technique. The results show that ACh at lower concentrations increases the inward K+ current, in contrast, ACh at higher concentrations inhibits it. Treated with d-Tubocurarine (d-Tub), an antagonist of the nicotine ACh receptor (nAChR) inhibits the inward K+ current by 30%. Treated with atropine (Atr), an antagonist of the muscarine (Mus) ACh receptor (mAChR) also inhibits it by 36%. However, if guard cell protoplasts are treated with d-Tub and Atr together, the inward K+ current is inhibited by 60%-75%. Tetraethylammonium chloride (TEA), a strong inhibitor of K+ channels has no effect on the inward K+ current regulated by ACh, suggesting that there are inward K+ channels modulated by AChRs on the membrane of the guard cell protoplasts. These data demonstrate an ACh-regulated mechanism for stomatal movement.

关键词： acetylcholine acetylcholine receptor inward K+ current guard cell.

inside,interior,internal,inner和inward辨析

在线全文

学校读者我要写书评

暂无评论

大学英语 1999年第11期 37-37页

作者：王保安

The effects of rises in external K^+ on the hyperpolarization-activated cation current I_h in rat dorsal root ganglion neurons

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2009年第8期52卷 1258-1263页

作者： DU ZhengQing WU WenJie ZHOU YuFen Department of Environmental Science Shanxi University of Finance and EconomicsTaiyuan 030006China

The effects of rises in external K+(Kext) were examined on the hyperpolarization-activated cation current(Ih) in rat dorsal root ganglion neurons using the whole-cell patch clamp *** results showed that Kext increased Ih in a certain concentration and voltage-dependent *** the basal Kext level(4 mmol/L),Ih had a maximal amplitude of 1085 ± 340 pA which was enhanced by ～45% and ～92% at 8 and 16 mmol/L Kext,*** midpoint activation voltage was significantly shifted from -98 mV in the hyperpolarizing direction by 8 and 12 mV at 8 and 16 mmol/L Kext,respectively with alteration of the activation course of *** short time constants of activation became longer with the increasing amplitude of the command potential upon rises in *** long time constants became *** reversal potentials were shifted in the positive direction without significant alterations upon rises in *** to the functional role of Ih,Kext increased Ih,resulting in an enhanced neuronal excitability,which might produce activation potential abnormality and perhaps neuropathic pain involved.

关键词： hyperpolarization-activated inward current external potassium dorsal root ganglion neurons patch clamp

Multiple satellites observation evidence:High-m Poloidal ULF waves with time-varying polarization states

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2019年第3期3卷 190-203页

作者： Chao Wei Lei Dai SuPing Duan Chi Wang YuXian Wang State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences

We report multi-spacecraft observations of ULF waves from Van Allen Probes(RBSP), Magnetospheric Multiscale(MMS), Time History of Events and Macroscale Interactions during Substorm(THEMIS), and Geostationary Operational Environmental Satellites(GOES).On August 31, 2015, global-scale poloidal waves were observed in data from RBSP-B, GOES and THEMIS from L=4 to L=8 over a wide range of magnetic local time(MLT). The polarization states varied towards purely poloidal polarity. In two consecutive orbits over 18 hours, RBSP-A and RBSP-B recorded gradual variation of the polarization states of the poloidal waves; the ratio(|B_a|/|B_r|) decreased from 0.82 to 0.13. After the variation of polarization states, the poloidal ULF waves became very purely poloidal waves, localized in both L and MLT. We identify the poloidal wave as second harmonic mode with a large azimuthal wave number(m) of –232. From RBSP particle measurements we find evidence that the high-m poloidal waves during the polarization variations were powered by inward radial gradients and bump-on-tail ion distributions through the N=1 drift-bounce resonance. Most of the time, the dominant free energy source was inward radial gradients, compared with the positive gradient in the energy distribution of the bump-on-tail ion distributions.

关键词： poloidal waves polarization rotation bump-on-tail inward gradient

A study on the factor market distortion and the carbon emission scale effect of two-way FDI

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Population,Resources and Environment 2019年第2期17卷 145-153页

作者： Mengqi Gong Haiyun Liu Rao Muhammad Atif Xu Jiang School of Economics Huazhong University of Science and TechnologyWuhan 430074China Department of Economics COMSATS University IslamabadLahore CampusLahorePakistan School of Public Administration Huazhong University of Science and TechnologyWuhanChina

Based on the data of 30 Chinese provinces for the period from 2004 to 2015,this paper expounds the carbon emissions effect of two-way foreign direct investment (FDI) from the perspective of scale effect and factor market *** study uses Kaya identity to decompose carbon emission and construct simultaneous equations model to empirically examine the factor market distortion and the carbon emission scale effect of two-way *** results show that the inward foreign direct investment (IFDI) increase regional carbon emission through scale effect and also exacerbates factor market distortion in China,whereas the outward FDI trends reduce carbon emission and reduces factor market distortions in *** study also shows that human capital,research and development (R&D),trade openness,and capital accumulation are important determinants of two-way ***,the study proposes that IFDI policies should focus on acquiring green *** addition,the domestic enterprises should be encouraged to participate in global business.

关键词： Factor market distortions inward foreign direct investment (IFDI) outward foreign direct investment (OFDI) scale effect carbon emissions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wave-Ice interaction

海洋预报 2001年第z1期18卷 22-34页

作者：沈奚海莉 Dcpamcent of CiVilEnvironmental Engineering

The growth and movement of sea ice cover are influenced by the presence of wave tield. In turn, the wave field is influenced by the presence of ice cover Their interaction is not fully understood. In this paper, we discuss some curent understanding on wave attenuation when it propagates through frag- mented ice cover. ice drift due to the wave motion, and the growth characteristics of ice cover in wavc field.

关键词： ocean collision drift tidal viscosity inward granular tides permeability dissipation

Neigong Science:A Gem in the East Physical Culture

在线全文

学校读者我要写书评

暂无评论

北京体育大学学报 1995年第S2期18卷 9-13页

作者： LIN Boyuan (43 years old, associate professor)

Neigong (internal execist) in a kind of exercise for health promotion through adjusting body, breath,mind and raising the extent of being in order of the body. The theory of neigong was developed on the basis of Chinese philosophic thought of maintaining softness, calmness and desireless, Chinese medical theory of internal organ channels, and various schools of daoyin breathing. Its research scope includes both fit-keeping exercises and wushu internal exercises. The practice of neigong emphasizes self-consciousness of the main body, an organic conception of the heaven and the man, calmness, and a return to the original essenee. Combining still with motion and making conces sion for advantages, the exercise is charecterizes by an inward inclined detachment. Neigong in China and similar exercises appeared in other Asian countries and areas represents a major school of the Oriental physical

关键词： internal exercise adjusting berath wushu daoyin inward inclined detachment an organic conception of the heaven and the man

ON THE FROZEN FORCE-FREE MAGNETIC FIELD

在线全文

学校读者我要写书评

暂无评论

Science in China,Ser.A 1977年第2期 158-176页

作者：胡文瑞 Institute of Mechanics Academia Sinica

In this paper, the general features of the axial symmetrical force-free field with large magnetic Reynold number (R_m>>1) are discussed. By introducing the magnetic surface function, it is possible to derive a set of fundamental equations describing force-free field of frozen type from both the conditions of force-free field and magnetic induced equations. The configuration of a magnetic field is actually of a forzen force-free field only if all the three relations of the fundamental equations are satisfied. We present several consistent solutions. For the static cases, the force-free factor α of the field need not be a constant. On condition that α is a constant, these solutions are satisfied also as if the azimuthal velocity component was a function of the magnetic surface function. The consistent solutions of some steady three-dimensional motion and the similar solutions of the unsteady motion are obtained. Finally, the structures and the evolutions of the magnetic rope are analysed, and some more

关键词： unsteady symmetrical analysed satisfied frozen actually satisfy derive inward describing

PRELIMINARY RESULTS OF FEEDBACK EQUILIBRIUM EXPERIMENT IN CT-6B TOKAMAK

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1981年第1期26卷 12-15页

作者：张泽湘任育峰沈仲卿 Institute of Physics Academia Sinica

Ⅰ. EXPERIMENTAL FACILITIES The machine CT-6B is a shell-less Tokamak. Its major parameters are: radius, R_o=45 cm; the radius of the vacuum chamber, 15 cm; the radius of the Mo limiter, 13 cm; the time constant for vertical field penetrating through the vacuum chamber, 0.3 ms. The plasma equilibrium is maintained by a programmed vertical field and feed-

关键词： radius vacuum chamber penetrating programmed inward heating maintained magnitude winding