Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to m...Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to morphine withdrawal. Then, they were subjected to two kinds of learning: operant conditioning and spatial learning. Results The acquisition of both simple appetitive and cued operant learning was impaired after repeated morphine treatment. Withdrawal for 5 weeks alleviated the impairments. Single morphine exposure disrupted the retrieval of operant memory but had no effect on rats after 5-week withdrawal. Contrarily, neither chronic morphine exposure nor 5-week withdrawal influenced spatial learning task of the Morris water maze. Nevertheless, the retrieval of spatial memory was impaired by repeated morphine exposure but not by 5-week withdrawal. Conclusion These observations suggest that repeated morphine exposure can influence different types of learning at different aspects, implicating that the formation of opiate addiction may usurp memory mechanisms differentially.展开更多
Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate...Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate students＇ innovative spirit, help students improve their ability of analyzing and solving problems, and improve students＇ comprehensive quality. This paper will analyze the problems existing in practical teaching model of ideological and political lessons, and put forward the corresponding reform measures, hoping to innovate and perfect the practical teaching model.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China （No. 30470549）the National Basic Research Priorities Programme （973） of China （No.2006CBS00800）
文摘Objective To investigate whether repeated morphine exposure or prolonged withdrawal could influence operant and spatial learning differentially. Methods Animals were chronically treated with morphine or subjected to morphine withdrawal. Then, they were subjected to two kinds of learning: operant conditioning and spatial learning. Results The acquisition of both simple appetitive and cued operant learning was impaired after repeated morphine treatment. Withdrawal for 5 weeks alleviated the impairments. Single morphine exposure disrupted the retrieval of operant memory but had no effect on rats after 5-week withdrawal. Contrarily, neither chronic morphine exposure nor 5-week withdrawal influenced spatial learning task of the Morris water maze. Nevertheless, the retrieval of spatial memory was impaired by repeated morphine exposure but not by 5-week withdrawal. Conclusion These observations suggest that repeated morphine exposure can influence different types of learning at different aspects, implicating that the formation of opiate addiction may usurp memory mechanisms differentially.
文摘Strengthen the practical teaching is an important way to improve effectiveness of colleges＇ ideological and political lessons. It has an important role to stimulate the students＇ individuality development, cultivate students＇ innovative spirit, help students improve their ability of analyzing and solving problems, and improve students＇ comprehensive quality. This paper will analyze the problems existing in practical teaching model of ideological and political lessons, and put forward the corresponding reform measures, hoping to innovate and perfect the practical teaching model.
