To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca 2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits...To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca 2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits were injected with DOX , 8 rabbits with DOX and Tau, and 9 rabbits with normal saline. Cardiac function , concentration of calcium in cardiomyocytes (Myo[Ca 2+ ] \%i\%), activity of SR Ca 2+ ATPase(SERCA2a), level of SERCA2a mRNA and Ca 2+ released channels(RYR2)mRNA were detected. The left ventricle tissues were observed by electron microscopy. The results showed that cardiac index, left ventricular systolic pressure, activity of SR Ca 2+ ATPase and level of SERCA2a mRNA decreased , while Myo[Ca 2+ ] \%i\% increased in DOX treated rabbits. DOX could not affect the level of RYR2 mRNA. Tau intervention could alleviate the increase of left ventricular diastolic pressure, Myo[Ca 2+ ] \%i\% and the decrease of SERCA2a mRNA induced by doxorubicin. The results suggested that downregulation of SERCA2a gene expression was an important mechanism of DOX induced cardiomyopathy and that Tau could partially improve the heart function by reducing calcium overload and alleviating downregulation of SERCA2a mRNA.展开更多
The current study endeavours to examine the extent to how authenticity, usage, and intensity of native English instruction impact EFL students behaviourally and linguistically at the preparatory year programme in CTE,...The current study endeavours to examine the extent to how authenticity, usage, and intensity of native English instruction impact EFL students behaviourally and linguistically at the preparatory year programme in CTE, where students undertake an intensive English course for one year. The programme is managed by an American company called Interlink and is entirely staffed by native English teachers. The implementation of this English instruction encompasses motivational, pedagogical, and administrative challenges that hinder its practicality for positive and achievable learning outcomes. To this end, this paper will attempt to address the sociolinguistic and historical profile of EFL in Saudi Arabia in order to present an overall picture of this study＇s context.展开更多
Objective To investigate whether estrogen modulates learning and memory and long-term potentiation （LTP） in the hippocampus of rats with Alzheimer＇s disease （AD）. Methods The rats were divided into ovariectomy （...Objective To investigate whether estrogen modulates learning and memory and long-term potentiation （LTP） in the hippocampus of rats with Alzheimer＇s disease （AD）. Methods The rats were divided into ovariectomy （OVX） and estrogen replacement therapy （ERT） groups. Rats in the ERT group received OVX, followed by ERT, while rats in the OVX group received only OVX. The rat model of AD was established by injection of 1 μL （10 μg/μL） amyloid-beta peptide 1-40（Aβ1-40） into the hippocampus. The learning and memory ability and LTP were determined by Morris water maze and electrophysiological method, respectively. Results The escape latency in Morris water maze significantly decreased in ERT group compared with that in OVX group （P 〈 0.05）. Besides, rats in ERT group exhibited a significant enhancement of the magnitude of LTP at 30 min after high-frequency stimulation （HFS）, compared with that in OVX group （P 〈 0.01）. Conclusion ERT can attenuate the cognitive deficits in the rat model of AD, and estrogen can regulate LTP and synaptic remodeling in AD rats.展开更多
Self-cancellation of modules having the finite exchange property is introduced. If a right R-module M has the finite exchange property, it is shown that M has selfcancellation if and only if EndR(M) is a strongly sepa...Self-cancellation of modules having the finite exchange property is introduced. If a right R-module M has the finite exchange property, it is shown that M has selfcancellation if and only if EndR(M) is a strongly separative ring. Using this result,some new characterizations of strong separativity are obtained.展开更多
文摘To investigate the effect of doxorubicin(DOX) on gene expression of the myocardial sarcoplasmic reticulum (SR)Ca 2+ transport proteins and the mechanism of taurine(Tau) protecting cardiac muscle cells, 9 rabbits were injected with DOX , 8 rabbits with DOX and Tau, and 9 rabbits with normal saline. Cardiac function , concentration of calcium in cardiomyocytes (Myo[Ca 2+ ] \%i\%), activity of SR Ca 2+ ATPase(SERCA2a), level of SERCA2a mRNA and Ca 2+ released channels(RYR2)mRNA were detected. The left ventricle tissues were observed by electron microscopy. The results showed that cardiac index, left ventricular systolic pressure, activity of SR Ca 2+ ATPase and level of SERCA2a mRNA decreased , while Myo[Ca 2+ ] \%i\% increased in DOX treated rabbits. DOX could not affect the level of RYR2 mRNA. Tau intervention could alleviate the increase of left ventricular diastolic pressure, Myo[Ca 2+ ] \%i\% and the decrease of SERCA2a mRNA induced by doxorubicin. The results suggested that downregulation of SERCA2a gene expression was an important mechanism of DOX induced cardiomyopathy and that Tau could partially improve the heart function by reducing calcium overload and alleviating downregulation of SERCA2a mRNA.
文摘The current study endeavours to examine the extent to how authenticity, usage, and intensity of native English instruction impact EFL students behaviourally and linguistically at the preparatory year programme in CTE, where students undertake an intensive English course for one year. The programme is managed by an American company called Interlink and is entirely staffed by native English teachers. The implementation of this English instruction encompasses motivational, pedagogical, and administrative challenges that hinder its practicality for positive and achievable learning outcomes. To this end, this paper will attempt to address the sociolinguistic and historical profile of EFL in Saudi Arabia in order to present an overall picture of this study＇s context.
基金supported by the National Natural Science Foundation of China (No. 30700938,30872656, 30700861, 30800451) the Natural Science Foundation of Liaoning Province, China (No. 20082078)
文摘Objective To investigate whether estrogen modulates learning and memory and long-term potentiation （LTP） in the hippocampus of rats with Alzheimer＇s disease （AD）. Methods The rats were divided into ovariectomy （OVX） and estrogen replacement therapy （ERT） groups. Rats in the ERT group received OVX, followed by ERT, while rats in the OVX group received only OVX. The rat model of AD was established by injection of 1 μL （10 μg/μL） amyloid-beta peptide 1-40（Aβ1-40） into the hippocampus. The learning and memory ability and LTP were determined by Morris water maze and electrophysiological method, respectively. Results The escape latency in Morris water maze significantly decreased in ERT group compared with that in OVX group （P 〈 0.05）. Besides, rats in ERT group exhibited a significant enhancement of the magnitude of LTP at 30 min after high-frequency stimulation （HFS）, compared with that in OVX group （P 〈 0.01）. Conclusion ERT can attenuate the cognitive deficits in the rat model of AD, and estrogen can regulate LTP and synaptic remodeling in AD rats.
文摘Self-cancellation of modules having the finite exchange property is introduced. If a right R-module M has the finite exchange property, it is shown that M has selfcancellation if and only if EndR(M) is a strongly separative ring. Using this result,some new characterizations of strong separativity are obtained.
