金属硫蛋白对小鼠大脑皮层细胞的保护作用

用MT-Ⅲ重组腺病毒感染原代培养的小鼠大脑皮层神经细胞,研究MT-Ⅲ是否对谷氨酸和Aβ引起的神经毒性有保护作用.MTT法和PI-Hochest(33342)双染色法分析细胞成活显示,MT-Ⅲ的表达能有效地提高谷氨酸和Aβ处理后的神经细胞相对成活率,并在由谷氨酸诱导的细胞凋亡通路中阻碍CDK5/P35中的P35向P25裂解而保护神经元.     

2-硝基-4''''-羟基二苯胺(HC Orange No.1)在鲫鱼体内富集行为研究

研究了鲫鱼暴露于0．9975mg／L2-硝基-4’-羟基二苯胺(HC OrangeNO．1)96h后在实验室鱼水系统中的归趋．用高效液相色谱分析了暴露鱼样和暴露水样在6h，12h，24h，36h，48h，60h，72h．96h的浓度．鱼样的回收率为84．4％～91．7％之间，相对标准偏差(RSD)为0．51％．HC Orange NO．1在水体中的浓度在24h内下降较快，之后维持稳定；鱼体中化合物的积累在36h达到最大，之后稍有下降．利用BCF的快速测定方法和传统方法算出的IgBCF分别为2．35和2．14。     

鸡西盆地早白垩世穆棱组海相沟鞭藻的发现及其古环境意义

最近在黑龙江省东部鸡西盆地穆棱河右岸青龙山一带穆棱组标准剖面地层中发现多属种海相沟鞭藻化石: Circulodinium cingulatum He et al., Circulodinium attadalicum (Cookson et Eisenack) Helby, Palaeoperidinium cretaceum Pocock, Oligosphaeridium totum Brideaux及Sentusidinium sp., 它们都是世界各地早白垩世海相地层中广泛分布的属种. 这些化石的发现表明, 在穆棱组沉积时期, 鸡西盆地曾经历过海侵或海泛, 修正了以往所谓的穆棱组为纯陆相沉积的观点, 并为穆棱组地质时代的确认提供了新的依据, 也为黑龙江省东部早白垩世古地理的重建提供了重要的海相沉积依据.     

热河生物群中戈壁兽一新种: 其时代意义及哺乳动物若干特征演化

描述了产自辽宁西部下白垩统义县组的一种新的哺乳动物——索菲娅戈壁兽(Gobiconodon zofiae sp. nov.). 新种耳区的岩骨前骨板提供了第5脑神经Ⅱ, Ⅲ分支的汇合出口, 这可能是类似犬齿兽类的原始特征. 与爬兽一样, 新种保存了骨化的麦氏软骨, 表明它具有与下颌分离的耳区结构, 为哺乳动物中耳的起源和演化提供了新的直接的化石证据. 新种以I¹/I₁增大, 眶下孔靠后, 4个颏孔及牙齿结构区别于戈壁兽已知种. 新材料所具有的齿列咬合关系表明戈壁兽的上臼齿数目应为4个而不是5个. 在热河生物群已知的50余种脊椎动物中大多是东北亚的土著种类, 因之在进行动物群及时代洲际对比时有一定困难. 索菲娅戈壁兽的发现使热河生物群可以直接与北美及亚洲其他脊椎动物群进行对比. 戈壁兽的出现支持同位素测年数据, 表明含戈壁兽的义县组时代可能为早白垩世.     

求解对流扩散方程的一类AGE方法

结合Crank-Nicolson格式和第二类Saul’yev非对称格式,设计求解对流扩散方程的交替分组显式方法.得到求解对流扩散方程的交替分组显式方法为该方法是绝对稳定的,且使用方便,适合并行计算,具有较好的精度.     

农作物的主要代表——稻的技术和文化发展

在我国,至今已发现稻作遗址170多处,目前所知世界上最早稻谷遗存是在湖南道县玉蟾岩和江西万年仙人洞.其中,玉蟾岩发现少量稻谷壳,保留部分野生稻特征,属栽培不久籼粳尚未完全分化的古稻,样品年龄为12000～9900 aBP;仙人洞遗址的上层年龄为12000～9000 aBP,有大量栽培稻的植硅石.这些稻作遗存表明,稻是我国最早栽培的作物之一.     

脑电多极子模型在老年性痴呆诊断中的应用

为寻求反映早老性痴呆(Alzheimer's disease,AD)病情变化的脑电图(EEG)特征参数,探索AD诊断新方法,尝试采用移动电流多极子模型及其适合度(GOF)、比适度(DD)等评价参数对AD患者脑电源活动和EEG样本进行了模拟计算与参数分析.仿真与分析结果表明:多极子模型较偶极子模型能够更好地拟合AD患者因脑沟回裂扩大引起皮层神经电源活动病变,具有较高的GOF参数值和较大的DD参数值变化;多极子模型DD参数均值和标准方差的乘积与目前临床使用的痴呆简易量表诊断值有明显的线性关系.追踪AD患者的多极子模型参数并对照其fMRI脑血流图像随痴呆进程变化的观察结果也提示DD有关参数有可能作为新的诊断指标用于痴呆病情监测.     

Distribution of CRH-and ACTH-like immunoreactive cells in amphioxus,Branchiostoma belcheri

Immunocytochemical studies on the nervous system,Hatschek's pit,digestive tract and gonads tissues of an amphioxus(Branchiostoma belcheri)were performed using polyclonal antibodies against human corticotrophin-releasing hormone(CRH)and human adrenocorticotropin(ACTH).The results showed that many CRH-like immunoreactive neurons were distributed specifically on the dorsal side and ventral side of brain vesicle,while a few CRH-like neurons and their fibers in spinal cord.At the same time,the epithelial cells in the basic region of Hatschek's pit were shown immunopositive to CRH antibody.In gonads(ovary and testis),CRH-immunopositive substance was localized in the cytoplasm near oocyte nucleus and in early spermatogenic cells.ACTH-like immunoreactivities were observed specially in the neurons and their protrusions localized on the ventral side of the brain vesicle and in spinal cord,and also in epithelial cells of Hatschek's pit,enteric neurons of digestive tract,oocytes in ovary and in early spermatogenic cells as well.It was found for the first time that CRH-like neurons existed in the middle region of brain vesicle(corresponding to the hypothalamus of vertebrates)and ACTH-like immunopositive cells existed in Hatschek's pit,implying that a control mechanism between brain vesicle and Hatschek's pit maybe had been already built in amphioxus as that in vertebrates.The present study will provide new morphological evidence for the origin and evolution of ACTH.In addition,the immunoreactivities of CRH and ACTH in the digestive tract and gonads suggested other physiological function of CRH and ACTH in amphioxus.     

P?un’s systems as models of economic systems

In the paper a concept for modeling the economic systems by the formalism of P?un’s systems is proposed. The main idea is to represent economic systems as homomorphic images of Petri nets corresponding to the (super) cells of P?un’s systems.     

New evidence for human occupation of the northern Tibetan Plateau, China during the Late Pleistocene

The described stone artifacts are recovered from the 70 m-high terrace (4600 m a.s.l.) at the southeastern shore of the Siling Co on the northern Tibetan Plateau. The terrace was formed during the Interstadial period before the LGM, ca. 40-30 ka B.P. based on paleoenvironmental research. The Paleoliths from the Siling Co provide evidence for early human occupation of the northern Tibetan Plateau. They show technological and typological affinities with the European Middle Paleolithic suggesting that the early human occupation here might relate to migratory waves during the Late Pleistocene that dispersed humans across the Old World.