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中日产川芎的matK、ITS基因序列及其物种间的亲缘关系   总被引:9,自引:0,他引:9  
目的分析中国产川芎Ligusticum chuanxiong Hort.及日本产川芎Cnidium officinale Makino的核基因组ITS和叶绿体基因组matK序列,为探讨中日产川芎物种间的亲缘关系提供分子依据。方法采用PCR直接测序技术测定川芎和日本川芎的ITS基因和matK基因核苷酸序列并作序列变异分析。结果川芎和日本川芎的matK序列长度均为1268 bp,编码422个氨基酸。ITS1-5.8S-ITS2序列长度均为699 bp,其中18S rRNA基因3′端序列54 bp,ITS1序列215 bp,5.8S rRNA基因序列162 bp,ITS2序列222 bp,26S rRNA基因5′端序列46 bp。根据排序比较,川芎原植物与其商品药材间的matK基因和ITS基因序列完全相同,而川芎与日本川芎间matK基因则仅有1个变异位点,即在上游959 nt处1个转换替代(T→C),反映在氨基酸序列则发生一个非同义取代V(GTG)→A(GCG);ITS基因也仅有1个变异位点,即在ITS1上游54 nt处1个转换替代(T→C)。结论通过进化速率较快的基因序列同源性分析,基本可以认为中日所产川芎基原一致,日本川芎学名似应改为Ligusticum chuanxiong Hort.。  相似文献   
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Abstract The present study was performed in order to determine whether spontaneous K-complex are induced by sensory stimuli. Electroencephalogram (EEG) segments in stage 2 sleep containing an evoked K-complex or spontaneous K-complex were separately averaged with respect to the peak of N300, one of the main components constituting the K-complex. Small negative and positive components were found immediately before the main components of spontaneous K-complex in averaged EEG. These two components were judged to correspond to N100 and P200 induced by the sound stimulus. The present findings suggest that the spontaneous K-complex is not a spontaneous phenomenon but that it is induced by sensory stimuli.  相似文献   
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Abstract Behavior of event related potential (ERP) components in the drowsy state was examined in nine subjects using oddball paradigm. A component with peak latency of 300 msec, N300, was superimposed on ERP in the drowsy state. N300 appeared also in stage 1 of NREM sleep and closely resembled vertex sharp wave evoked by sound stimulation in both scalp distribution and peak latency. It was suggested that N300 recorded in the drowsy state and vertex sharp wave recorded in stage 1 of NREM sleep are generated by the identical synchronizing mechanism in the brain.  相似文献   
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Abstract N300 appearing in response to sound stimulus was used as an index to determine the occurrence of cortical activity characterizing REM sleep. In 5/10 subjects, marked reduction of N300 amplitude occurred even in the period of 0.5-2.5 min immediately preceding the appearance of muscle atonia characterizing REM sleep. Neither muscle atonia nor rapid eye movements appeared prior to the marked reduction of N300 amplitude in any subject. This suggests that the cortical activity characterizing REM sleep sometimes occurs a few minutes (or less) earlier than other physiological phenomena.  相似文献   
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MALIGNANT HEMANGIOENDOTHELIOMA   总被引:3,自引:0,他引:3  
Background. The administration of interleukin-2 (il-2 ) has recently been reported to be favorable for treating malignant hemangioendothelioma (mhe ). Methods. Two patients with mhe responded well to intra-lesional injections of recombinant il-2 (ril-2 ) without major side effects. The purpose of this study was to characterize cells infiltrating the regressing tumor following ril-2 treatment. Immunohistochemical studies were performed on biopsy specimens taken from ril-2 -injected lesional skin. Results. It was shown that CD8+ lymphocytes and CD56+ natural killer (nk ) cells infiltrated at the ril-2 -injection sites, suggesting that these cells contributed to the tumor regression. In addition, MHE cells bore intercellular adhesion mole-cule-1 (icam -1) whose expression was augmented by rn-2 injections. Conclusions. These findings suggested, that ril-2 not only induces lymphokine-activated killer (lak ) cells and nk cells, but also facilitates these cytotoxic cells to adhere to MHE cells by enhancing icam -1 expression of tumor cells.  相似文献   
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