海南岛土著药用木本植物区系及其应用现状调查

对海南岛野生土著药用木本植物区系的研究表明,该区系由70科206属332种组成,呈现出热带北缘特征,物种主要集中在岛南部、中南部和东南部地区。本文还对海南岛药用植物资源的应用现状及发展思路作了探讨。     

小兴安岭地区原麝冬季食性研究

2004 年2 ～3 月和2004 年11 月至2005 年1 月在黑龙江省通河县龙口林场,对原麝冬季的食性进行了研究。采用粪便显微组织学分析技术分析原麝冬季采食植物的种类组成和比例,并测定了主要取食的9 种木本植物及苔藓和蕨类植物的营养成分。研究结果表明,原麝冬季取食的植物共计46 科66 种,其中兴安杜鹃、光萼溲疏、五角槭、羊胡子苔草分别占32.7%、7.8%、5.81%、5.56%, 是原麝冬季主要取食的植物种类,占取食植物的51.9% 。木本植物枝叶是原麝冬季的主要食物,在冬季食物组成中所占百分比最高, 达75.0% 。对草本植物、蕨类、苔藓、地衣的取食量均较小。冬季原麝比较喜欢采食蛋白含量高的植物,采食部位主要为植物木质化较低的当年枝顶端部分。藓类主要出现在1 ～3 月份的食物中。     

Intra-Urban Human Mobility and Activity Transition: Evidence from Social Media Check-In Data

Most existing human mobility literature focuses on exterior characteristics of movements but neglects activities, the driving force that underlies human movements. In this research, we combine activity-based analysis with a movement-based approach to model the intra-urban human mobility observed from about 15 million check-in records during a yearlong period in Shanghai, China. The proposed model is activity-based and includes two parts: the transition of travel demands during a specific time period and the movement between locations. For the first part, we find the transition probability between activities varies over time, and then we construct a temporal transition probability matrix to represent the transition probability of travel demands during a time interval. For the second part, we suggest that the travel demands can be divided into two classes, locationally mandatory activity (LMA) and locationally stochastic activity (LSA), according to whether the demand is associated with fixed location or not. By judging the combination of predecessor activity type and successor activity type we determine three trip patterns, each associated with a different decay parameter. To validate the model, we adopt the mechanism of an agent-based model and compare the simulated results with the observed pattern from the displacement distance distribution, the spatio-temporal distribution of activities, and the temporal distribution of travel demand transitions. The results show that the simulated patterns fit the observed data well, indicating that these findings open new directions for combining activity-based analysis with a movement-based approach using social media check-in data.     

A high efficient method of constructing recombinant Bombyx mori (silkworm) multiple nucleopolyhedrovirus based on zero‐background Tn7‐mediated transposition in Escherichia coli

A high efficient way for generation of recombinant Bombyx mori (silkworm) multiple nucleopolyhedrovirus by Tn7‐mediated transposition in Escherichia coli was performed. The new system consists of a conditional replication donor vector pRCDM and an attTn7 site blocked E. coli containing BmNPV‐Bacmid. The donor vector contains a replication origin derived from R6Kγ, which propagated only in host cells with pir gene expression decreased in the transposition background greatly. Compared with original vector derived from pUC, the transposition efficiency increased from 5.7 to 66% (≈10 fold) when using conditional replication vector pRCDM transposition into original BmDH10Bac. A further effort to decrease the transposition background was made by blocking the attTn7 site in host E. coli genome. The resulting attTn7 occupied BmDH10BacΔTn7 resulted in a significant increase from 5.7 to 23% (≈4 fold) in the efficacy of generate recombinant BmNPV Bacmid by transposition. Furthermore, the transposition of BmDH10BacΔTn7 with pRCDM resulted typically in 100% white colonies, and it indicated that a zero transposition background was accomplished. This high efficient and zero background transposition system provides a new simple and rapid method for construction of recombinant BmNPV used to express target genes or produce gene‐delivery virus particles in silkworm. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009     

旋转磁场联合5-FU对SP2/0细胞超微弱发光强度的影响

目的:研究旋转磁场(RMF)联合氟尿嘧啶(5-Fu)对小鼠骨髓瘤细胞(SP2/0)超微弱发光的影响,探讨两者联合对肿瘤细胞的杀伤作用.方法:SP2/0细胞分为四组:对照组,单纯5-FU化疗组(单化组),单纯磁疗组(单磁组),磁场联合5-FU组(磁化组).用RMF、5-FU作用于SP2/0细胞,化学发光仪进行分析.结果:对照组的化学发光强度值最低,单化组、单磁组、磁化组化学发光强度值均明显高于对照组(P均<0.001).单磁组低于单化组及磁化组,有明显差别(P<0.001);磁化组的化学发光强度值最高,高于单化组(P<0.001).结论:磁场和5-Fu均可引起SP2/0细胞化学发光强度值的变化,以磁场联合5-Fu的化学发光强度值变化最明显,提示磁场单独及联合5-FU对SP2/0细胞有明显的杀伤作用.其机理可能与旋转磁场和5-FU引起细胞自由基增高有关.     

Event-related potentials in a Go/Nogo task of abnormal response inhibition in heroin addicts

Inhibitory control dysfunction is regarded as a core feature in addicts. The major objective of this study was to explore the time course of response inhibition in chronic heroin addicts and provide the neu-rophysiological evidence of their inhibitory control dysfunction. The amplitudes and latencies of ERP components were studied in fourteen heroin addicts (mean duration of heroin use being (13.54±5.71) years (Mean±SD), average abstinence being ((4.67±6.44) months)) and fourteen matched healthy con-trols with a visual Go/Nogo task. Our results showed that heroin addicts demonstrated significantly larger Go-N2 amplitudes which results in a decreased N2 Go/Nogo effect, but no statistically significant differences were found between heroin addicts and controls in P3. The ERP data suggest that fronto-central areas of heroin addicts were impaired during the inhibition process (200—300 ms) and over-activated to targets. The impaired early process might reflect an abnormal conflict monitoring process in heroin addicts. These results consolidate the inhibitory control dysfunction hypothesis in chronic heroin users.     

荒漠油蒿（Artemisia ordosica）根围AM真菌分布与土壤酶活性

于2007年10月在油蒿(Artemisia ordosica)集中分布区选取4个典型样地,分别从0～10cm、10～20cm、20～30cm、30～40cm和40～50cm土层采集根围土样,分离其丛枝菌根(arbuscular mycorrhiza,AM)真菌并测定了3种土壤酶活性.结果表明,在各样地0～50cm土层中油蒿根系AM真菌菌丝定殖率均很高,有典型的泡囊与丛枝结构.菌丝定殖率与泡囊定殖率呈显著正相关,但菌丝、泡囊和丛枝定殖率与AM真菌孢子密度和土壤酶活性之间都无相关性;孢子密度在不同样地及采样深度间差异明显,与土壤有机质、速效磷和速效氮含量都呈一定正相关关系.孢子密度与脲酶和酸性磷酸酶活性有显著或极显著相关关系,与碱性磷酸酶活性之间的相关性受到土壤pH的显著影响.孢子密度的峰值出现在0～10cm表层土,并随土壤剖面深度增加而降低.土壤酶活性在土壤垂直剖面显示与孢子密度同样的规律.不同样地间AM真菌分布及油蒿根系定殖率的差异表明,油蒿与AM真菌之间有良好共生性,对维护荒漠生态环境系统结构的完整性具有重要意义.     

部分桂花品种亲缘关系及特有标记的ISSR分析

利用ISSR分子标记,以柊树[Osmanthus heterophyllus (G.Don.) P.S.Green]和华东木犀(Osmanthus cooperi Hemsl.)为对照种,研究了桂花(Osmanthus fragrans Lour.)81个品种、1个野生种之间的亲缘关系.结果显示;(1)28个引物共获得280个位点,其中多态性位点263个,多态性比率达93.93%,在4个品种群中,银桂品种群的Shannon信息指数(0.370 7)和遗传多样性指数(0.241 7)最高.(2)遗传变异估算结果显示:桂花遗传分化系数为57.39 %,大部分变异存在于品种群之间.(3)聚类分析结果显示,以遗传相似系数0.71为截值,可将84份种质分成 4类,各品种群的品种往往先聚在一起.其中四季桂品种群与秋季开花的3个品种群遗传距离较远,色质较深的金桂品种往往与丹桂品种聚在一起.研究表明,基于ISSR分子标记的聚类结果与基于形态的传统分类学的结果基本相符;引物ISSR12和ISSR27结合可以将84份种质区别开来.     

应用蛋白组方法筛选血浆中乙肝病毒PreS1结合蛋白

目的筛选血浆中乙型肝炎病毒PreS1结合蛋白。方法表达纯化了PreS1-谷胱甘肽-S-转移酶（glutathione—S-transferase,GST）融合蛋白,利用该蛋白与血浆进行Pull—down实验,并设立GST与血浆Pull—down,GST、PreS1-GST与PBS Pull—down对照,Pull-down产物进行双向电泳分离（2-DE）,差异蛋白点通过质谱鉴定。结果成功表达纯化出PreS1-GST融合蛋白,通过双向电泳分析发现一个PreS1特异结合蛋白,经质谱鉴定为含锚蛋白重复序列的蛋白57（ANKRD57）。结论锚蛋白重复序列的主要功能是介导蛋白质与蛋白质之间的相互作用,ANKRD57与PreS1特异结合后的生理功能值得深入研究。     

太湖地区湿沉降中氮磷输入量 ——以常熟生态站为例

2003年6月—2004年5月,在中国科学院常熟生态站(31°32′45″ N ,120°41′57″ E)连续定位收集降雨,分析其中颗粒态和溶解态氮磷浓度,并对期间太湖地区氮磷湿沉降动态进行研究.结果表明：湿沉降氮输入量的季节变化显著,夏、春季高,秋、冬季低;湿沉降输入氮中88.2%为溶解氮（dissolved itrogen,DN）,11.8%为颗粒氮（particle nitrogen,PN）;湿沉降输入磷中溶解磷（dissolved phosphorus,DP）和颗粒磷（particle phosphorus,PP）比例分别为53.3%和46.7%;中、小雨携带的总氮（total nitrogen,TN）、总磷（total phosphorus,TP）污染物通量大于大、暴雨;太湖地区每年湿沉降输入TN、TP分别为30.2 kg·hm^-2和1.1 kg·hm^-2,且所有降雨中DN浓度均大于水体富营养化阈值,92.5%的降雨中DP大于水体富营养化阈值.