中文摘要：

目的：研究样本量大小对针刺腧穴脑功能性磁共振成像（fMRI）激活区定位的影响.方法：选取健康志愿者26例,其中男14例,女12例;年龄19～32岁,平均（23.15±2.78）岁.采用改良组块设计方案,针刺左侧足三里穴行fMRI 扫描,对符合实验条件者的21例依次分别标为1、2、3……21号,按照随机分组的原则,随机抽取5例,定为R5组,再在21例中随机抽取8、11、14、17例,定为R8、R11、R14和R17组.实验数据采用AFNI软件分析处理,处理过程大体上分为数据格式转换、计算个体统计参数图、计算组分析脑活动区以及活动区显示阈值校正等4个步骤,采用Monte Carlo模拟阈值校正方法（P＜0.05,α＜0.05）确定脑功能激活区,分别得出不同分组及全体组分析结果.结果：R5、R8、R11、R14、R17组均见不同程度脑内活动区,R5组脑内活动区表现为信号降低,其他各组则表现为部分区域信号降低,部分区域信号升高;R5～R17组间激活区域差别明显.结论：样本量的大小对针刺fMRI研究结果的影响十分明显;针刺fMRI研究样本量应尽量大,具体的样本大小,有待进一步研究.

英文摘要：

Objective：To observe the effects of sample size on fMRI during acupuncture at ST36. Methods：The study was per formed on 26 right-handed healthy adult volunteers. Fourteen male and twelve female subjects, 19-32 years old （average 23.15±2.78 years old）, participated in the study. An improved block design was used in the experiment and manual acupuncture was applied at volunteers＇ left ST36. The functional data was acquired by a GRE EPI sequence （TR/TE/FA= 4000 ms/ 50ms/90° , SL 3.0mm, spacing 0.75mm, FOV 192 minx 192 ram, resolution 64X64）. Individual subject that met the study requirement was first labeled with number of 1, 2, 3, …, 21 and then randomly grouped with sample size of 5, 8, 11, 14, 17 in turn and labeled as group R5, R8, …, R17, respectively. Images were processed using the AFNI software program and its process procedure was generally divided into four steps, i.e. data format conversion, calculation of the individual statistical parametric mapping, group analysis for activated brain areas and threshold correction with Monte Carlo simulation. The level of significance was threshold at P〈0.05 and produced a false positive discovery rate, α〈0.05. Results： All groups had shown varying activated areas. Group as labeled R5 showed mainly decreased signals of activated brain areas, while other groups showed both increased and decreased signals. Group R5 R17 demonstrated different activated areas. Conclusion： Sample size has significantly influence on acupuncture fMRI study, so the sample size should be large enough, but what is the appropriate size is up to further study.