鸡脚参中一个新木脂素

从鸡脚参[Orthosiphon wulfenioides (Diels)Hand.-Marzz.]根中提取分离了一个新的木脂素,命名为鸡脚参木脂素。其结构由NMR、MS等波谱分析确定。初步活性实验显示该化合物不具备抗真菌和抗肿瘤活性。     

珍稀鹤类巢址的空间聚类识别方法

依据2003年到2005年松嫩平原西部地区珍稀鹤类巢址调查数据,利用三种不同类型的指数进行分析研究:(1)拓扑指数,Voronoi图面积;(2)统计指数,Morishita指数;(3)空间指数,分维数.结果表明珍稀鹤类巢址空间格局具有明显的空间聚类分布,这三个指数使我们对珍稀鹤类巢址的聚类现象有了定量的认识,加深对自然保护区资源保护的重要性.     

Serum endothelin-1 and transforming growth factor-beta levels in the newborns with respiratory distress

The purpose of this present study was to evaluate the serum levels of ET-1 and TGF-beta in the newborns with respiratory distress. In this study, newborns with respiratory distress hospitalized into the Newborn Intensive Care Unit were included. The highest values of ET-1 and TGF-beta were obtained from newborns with diagnosis as meconium aspiration syndrome (5.70 +/- 5.87 pg/mL and 3.75 +/- 1.94 pg/mL, resp) in the sample obtained in the first six hours after birth, and these are statistically different from control group (P < .05). Also, same results were obtained for newborns with respiratory distress syndrome (3.37 +/- 1.59 pg/mL and 2.05 +/- 0.98 pg/mL, resp). After oxygen treatment, ET-1 values obtained in the first six hours of life were decreased regularly in the following days (P < .05). In the differentiating diagnosis of the respiratory distress of newborns, the investigation of ET-1 and TGF-beta levels is meaningful. The ET-1 levels investigated in the first six hours is more useful in determining the prognosis, and repeating ET-1 levels in the following days is more meaningful to determine clinical response.     

脂肪细胞因子 CTRP4转基因鼠的构建与鉴定

目的：建立人CTRP4基因的转基因小鼠,为脂肪细胞因子CTRP4的体内功能研究奠定基础。方法首先构建人CTRP4的转基因小鼠线性化表达载体,再利用显微注射的方法将载体注射入小鼠受精卵,从而构建人CTRP4的首建鼠（ Founder ）并与野生型小鼠交配繁殖得到F1代阳性小鼠,再通过近亲繁殖与测交的方法,得到CTRP4转基因纯合子小鼠,并通过PCR和western blot 的方法对纯合子小鼠进行鉴定。结果得到人CTRP4转基因小鼠纯合子小鼠两个品系,western blot鉴定该转基因小鼠心脏,肝脏,脑,肾脏等多种组织中均呈现CTRP4高表达。结论成功构建了人CTRP4转基因小鼠纯合子小鼠。     

内蒙古草原人类福祉与生态系统服务及其动态变化——以锡林郭勒草原为例

以锡林郭勒盟为研究区域,建立人类福祉评价指标体系,通过牧户问卷调查了解牧户对草原生态系统服务和福祉变化的认识,结合当地的自然环境、生态环境和社会经济等多方面的多年统计数据,采用专家打分法对牧民各福祉指标打分,对2001年和2010年牧民福祉变化进行了评估和分析。结果表明:收入、道路覆盖率、农村合作医疗保险和文化教育方面对牧民福祉变化贡献最大;生产资料持续供给能力下降是导致收入减少的主要方面;旗县的犯罪率,环境空气质量,饮食结构,离婚率等是导致牧民福祉下降的主要方面。有关研究结果为提高锡林郭勒盟人类福祉、生态保护和区域可持续发展政策制定提供科学依据。     

Production of DON-related trichothecenes byFusarium graminearum Schw from Krasnodarski krai of the USSR

34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals.     

Crystal structure of the M1 protein-binding domain of the influenza A virus nuclear export protein (NEP/NS2)

During influenza virus infection, viral ribonucleoproteins (vRNPs) are replicated in the nucleus and must be exported to the cytoplasm before assembling into mature viral particles. Nuclear export is mediated by the cellular protein Crm1 and putatively by the viral protein NEP/NS2. Proteolytic cleavage of NEP defines an N-terminal domain which mediates RanGTP-dependent binding to Crm1 and a C-terminal domain which binds to the viral matrix protein M1. The 2.6 A crystal structure of the C-terminal domain reveals an amphipathic helical hairpin which dimerizes as a four-helix bundle. The NEP-M1 interaction involves two critical epitopes: an exposed tryptophan (Trp78) surrounded by a cluster of glutamate residues on NEP, and the basic nuclear localization signal (NLS) of M1. Implications for vRNP export are discussed.     

小黄皮叶挥发油的化学成分

利用水蒸气蒸馏法提取小黄皮叶挥发油,运用毛细管气相色谱-质谱联用法对挥发油进行了分析,分离出40个峰,鉴定了其中的37种成分,所鉴定成分占挥发油总量的99.87%,其主要化学成分为单萜及倍半萜类化合物。     

Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex

The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S nuclear ribosomal DNA sequence and the intervening 5.8S region were sequenced from three individuals in each of eight taxa of the Mimulus guttatus species complex. Three discrete variants, or "types," of ITS sequences were found, among which 30%-40% of sites differed, compared with 1%-2% within types. Dot plots indicate that these types were not related by conspicuous rearrangements or inversions. More than one ITS type was often found in the same taxon, and two of three ITS types span species boundaries, indicating their presence prior to speciation. These ITS sequences showed essentially no positional homology with the nearest sequenced relative, tomato. In contrast, the 5.8S region was relatively unvaried, with 8 of 162 sites varied in the sample among all eight taxa. The phylogeny inferred by the most common ITS sequence type, rooted by the two other ITS types, agreed with isozymes in showing the distinctness of M. nudatus, M. laciniatus, and M. tilingii from the other five taxa.      

植物丝氨酸/精氨酸丰富(SR)蛋白的结构和功能及其在植物发育中的作用

丝氨酸／精氨酸丰富（SR）蛋白家族是真核生物中的一类剪接因子,在前体mRNA的组成性和选择性剪接中起作用。本文就近十几年来SR蛋白结构和功能及其在植物发育中的作用的研究进展作以介绍。