Modulation of neuronal activity of cerebellar fastigial nucleus by locus coeruleus stimulation in the rat

The effects of stimulating locus coeruleus (LC) on neuronal activity of cerebellar fastigial nucleus (FN) was investigated. Stimulation of LC elicited inhibitory, excitatory and biphasic (inhibition-excitation) responses from FN cells. The majority of responsive cells showed an inhibitory response with a latency of less than 10 ms. Injection of α adrenoreceptor antagonists phentolamine (ⅳ) could block the inhibitory response of FN cells to the LC stimulation, but propranolol (ⅳ), a β adrenoreceptor antagonist, could not. These results suggest that LC-cerebellar noradrenergic afferent fibers may be involved in the cerebellar sensorimotor integration process by exerting their modulatory action on the cerebellar nuclear cells' activities.     

Genetic expression in progeny of transgenic plants obtained by using pollen-tube pathway (or delivery) method and approach to the transformation mechanism

The origin and the recent progress of pollen_tube pathway method (PTPM) is described. The results of transforming wheat during 1990 to 1994 are reported briefly. They are: (ⅰ) Transformation frequencies were 3%-6%, even reached 13.5%; (ⅱ) the genetic expression of four continuous generations obtained from single individuals of transgenic plants by self_fertilization was investigated. Plants with higher expression of foreign gene were found in every generation (from T1 to T4), but a phenomenon of gene silence, in which the genotype contained foreign gene but did not express, was also observed. In addition, from the angle of fertilization biology the transformation mechanism of PTPM (or PTDM) was analyzed and discussed. It was considered that the essential principle of this method was just like that of protoplast method.     

手性衍生化试剂MTPEA酰胺衍生物的合成

本文报导了手性衍生化试剂ＭＴＰＥＡ酰胺衍生物的合成方法。Ｄ，Ｌ－２甲氧基－２－三氟甲基－２－苯基乙胺（ＭＴＰＥＡ）与十个光学活性羧酸在二环已基碳二亚胺（ＤＣＣ）的存在下直接反应；分别生成等量的非对映异构酰胺。通过ＩＲ、＾１Ｈ ＮＭＲ、＾１３Ｃ ＮＭＲ、ＭＳ及元素分析等方法测定了各酰胺的结构。此外，还讨论了酰胺分子在质谱中的裂解方式。     

Maize transformation via pollen tube pathway and the inheritance of transgene in progeny

The herbicide-resistant gene als was introduced into maize inbred line Qi319 through pollen-tube pathway. The inheritance of transgene was studied up to 33 generation. Transformation was performed by applying plasmid DNA carrying solution on the severed styles after self-pollination, or just prior to selfpoll/nation. After herbicide screening, PCR and Southern blot analysis, seventeen plants were confirmed positive in TO generation, and sixteen of them were self-bred to construct family to 33 progeny. Through PCR analysis and herbicide screening in offspring, four lines were confirmed following a 3 : 1 Mendelian segregation ratio. In other lines the numbers of positive plants were lower than expected. Therefore, it is necessary to select large population in progeny to produce stable inherited lines when transgene was delivered by pollen tube method.     

细胞凋亡的信号传导途径的研究进展

细胞凋亡是很多基因参与的细胞死亡的一种形式,细胞凋亡从发生到执行的过程存在着不同的信号途径,本文综述了细胞凋亡的三大信号途径：线粒体途径、死亡受体途径和内质网途径。了解细胞凋亡的信号途径及其相互联系有助于人们全面了解细胞凋亡的机制,从而达到对细胞的生死进行调控的目的。     

候选药物TW918对K-Ras突变型人肺腺癌A549细胞的体外抑制作用

探讨候选药物TW918对K-Ras突变型人肺腺癌A549细胞的体外抑制作用.以MTT法检测TW918对A549细胞的增殖抑制作用;流式细胞术检测A549细胞周期和凋亡的变化;Western blotting 检测相关蛋白的表达.结果表明:候选药物TW918可以以时间和剂量依赖性地抑制A549细胞的增殖,且作用72 h时抑制效果比吉非替尼高9.93倍;引起细胞周期阻滞于G1期,并诱导细胞发生凋亡;降低A549细胞中p-EGFR的表达,并抑制其下游PI3K/AKT/mTOR信号通路的激活.TW918对K-Ra     

CMIP5模拟的平流层21世纪温度变化趋势

21世纪平流层气候变化主要由两个因素所决定,一个是臭氧层恢复造成的变暖,另一个是温室气体增加造成的变冷。针对在这两种相反的辐射效应作用下,平流层气温如何变化这一重要问题, 使用CMIP5未来情景模拟试验的结果, 对2006-2100年间的平流层温度的变化趋势进行分析。结果表明, 臭氧恢复的增温效应在平流层低层起主导作用, 而温室气体增加的冷却效应在平流层高层起主导作用, 因此, 平流层低层(70 hPa 以下)呈变暖趋势, 而平流层中高层呈变冷趋势。通过对包含完整平流层的气候模式(高顶模式)和只包含部分平流层的气候模式(低顶模式)预估的温度趋势的差异进行分析, 发现高顶模式预估的变暖趋势大于低顶模式的结果, 这意味着模式是否包含完整平流层有可能对预估的平流层和对流层未来气候变化有重要影响。     

秦皇岛市外来入侵物种的调查分析

采用实地考察、文献词研与专家咨询相结合的方法,对秦皇岛市外来入侵物种的种类、来源地、入侵途径以及对生态环境的影响等进行了系统调查。结果表明,秦皇岛市外来入侵物种共计32科67种。其中,外来入侵植物22科57种;外来入侵动物10科10种。分析了外来物种的入侵途径和入侵危害,提出了应采取的必要防范和控制措施。     

水杨酸对水分胁迫下小麦根交替途径的影响

研究了水杨酸(SA)处理对水分胁迫下小麦抗氰交替途径容量(Valt)、实际运行活性(ρValt)与交替氧化酶AOX表达量的影响. 结果表明：未经SA处理的小麦在胁迫与非胁迫的条件下均存在抗氰呼吸, 水分胁迫可使小麦呼吸活性及基因转录水平下降. 水杨酸可以缓解水分胁迫的影响,增加抗氰交替途径活性,使Valt与ρValt显著提高,SA对小麦氰呼吸起到了诱导作用. Western杂交分析结果显示,小麦在不同处理下Valt与ρValt的差异与AOX蛋白水平的变化相关, 水杨酸(SA)处理时AOX的表达量     

脱氢枞胺-取代水杨醛Schiff碱的电喷雾串联质谱研究

 采用电喷雾电离串联质谱技术对7种最新合成的脱氢枞胺-取代水杨醛Schiff碱(DASSSB)样品进行了研究。结果显示,这些化合物的ESI-MS/MS裂解方式与它们分子中水杨醛苯环上取代基的性质和位置有关：当水杨醛苯环上4位连接供电子取代基时,分子以C=N双键断裂为主,生成 ［M+H-283］⁺ 碎片离子;当水杨醛苯环上5位连接吸电子取代基时,分子以C=N双键β位的C-C键发生断裂为主,生成 ［M+H-254］⁺ 碎片离子。DASSSB二级质谱产生的特征子离子可作为对此类化合物进行定性定量分析的依据。