城郊公路两侧主要森林类型铅含量及分布规律

对南京城郊３１２国道两侧主要森林类型林木不同器官中Ｐｂ含量和分布规律的研究表明,不同树种、同一树种不同器官中Ｐｂ含量有明显差异．火炬松对Ｐｂ污染的净化能力强于杉木、栎树．汽车尾气排放的Ｐｂ污染影响范围在离公路两侧１００ｍ以内,主要在４０ｍ以内范围．有林地土壤由于有林木及林下植被的覆盖,其Ｐｂ含量（尤其是表层０～２０ｃｍ范围内）明显降低,说明林分可有效地降低土壤中Ｐｂ的污染程度．林木不同器官对Ｐｂ尘的吸附率在１８０％～２８１％之间,以叶片吸附能力最强;不同树种比较,以松树吸附率为高     

金属硫蛋白导向血栓单抗化学偶联体的制备及性质研究

金属硫蛋白（ｍｅｔａｌｏｔｈｉｏｎｅｉｎ,简称ＭＴ）是一类低分子量、富含半胱氨酸的蛋白质,由于１个ＭＴ分子可结合７个金属离子,因此ＭＴ分子具有很强的金属结合特性［１,２］．本文一方面利用ＭＴ分子的高金属结合性能,另一方面利用苏州医学院血液研究所研制成...     

Investigation of actinomycete diversity in the tropical rainforests of Singapore

Five thousand actinomycetes were isolated from soil samples collected from rainforests in Singapore and the generic identities of these isolates were determined by using a procedure that combined morphological, chemotaxonomic and 16S rDNA sequence-based phylogenetic analyses. Actinomycetes belonging to a total of 36 genera were identified. The most abundant isolates are members of Streptomyces, Micromonospora, Actinoplanes, Actinomadura, Nonomuria, Nocardia and Streptosporangium. By phylogenetic analysis of 16S rDNA sequences of our isolates together with those of known actinomycete species, we also evaluated the species diversity of several genera including Streptomyces, Micromonospora, Nonomuria, and Actinomadura. We found that: first, the tropical isolates are present in most clades represented by known species; and second, many tropical isolates form new clades distant from the known species, indicating the presence of unidentified taxa at both species and genus levels. Based on these results, we conclude that actinomycete diversity in the tropical rainforest is very great and should represent an excellent source for discovery of novel bioactive compounds. Received 17 March 1999/ Accepted in revised form 24 June 1999     

枯否细胞在实验性肝癌细胞凋亡中的作用研究

探讨Kupffer细胞在大鼠实验性肝癌细胞凋亡中的作用。应用免疫组化方法和TUNEL法对单用二乙基亚硝胺（DENA）诱发的肝癌及用氯化钆（GC）或酶母多糖（ZM）分别阻塞或激活Kupffer细胞后,给以DENA所引起的大鼠肝癌中的增殖细胞核抗原（PCNA）、bax、bcl-2蛋白表达和肝癌细胞的凋亡进行了对比研究,结果显示：肝癌组织的增殖指数在ZM＋DENA组、DENA组、GC＋DENA组依次增高,而凋亡指数在上述各组依次降低。Bax阳性率在ZM＋DENA组明显高于DENA组（P＜0.05）,而ZM＋DENA组bcl-2阳性率明显低于DENA组（P＜0.05）。结果提示：Kupffer细胞可促进实验性肝部细胞凋亡。     

Tourism may trigger physiologically stress response of a long-term habituated population of golden snub-nosed monkeys

Wildlife tourism is a thriving form of nature-based tourism that can provide revenue for conservation funds,and increase public aware-ness of biodiversity conse...     

沙棘hrh-miRn458靶向转录因子WRI1调控油脂合成

转录因子WRI1(WRINKLED 1)在油脂合成过程中发挥重要调控作用,其转录和翻译水平调控机理以及下游的靶基因现已基本明确,但尚未见其转录后调控的报道。为探讨沙棘(Hippophae rhamnoides) hrh-miRn458与转录因子WRI1之间的靶向关系,并阐明其在果肉和种子发育过程中的表达模式,通过生物信息学方法预测hrh-miRn458成熟体序列及其与候选靶基因WRI1的结合位点,采用双荧光素酶报告基因检测和RNApulldown技术相结合的方法验证hrh-miRn458与WRI1基因之间的靶向关系,并应用qRT-PCR方法分析hrh-miRn458与WRI1在沙棘不同发育期果肉和种子油脂合成过程中的表达变化。结果表明,生物信息学预测WRI1基因的CDS区第309–327位与hrh-miRn458成熟体序列的15个碱基互补;荧光检测显示pmirGLO-WRI1-WT+hrh-miRn458 mimics显著抑制荧光素酶活性(P<0.001); RNA pull down实验证实hrh-miRn458与WRI1存在互作关系;不同发育期果肉和种子中hrh-miRn45...     

一种测定艰难梭菌荚膜多糖分子量的简便方法

本文采用两种规格的Ｓｅｐｈａｒｏｓｅ４Ｂ凝胶层析柱,测定了艰难梭菌荚膜多糖的分子量,并建立了一种较为简便、敏感的测定方法,对进一步研究英膜多糖的生物学特性提供了有利条件。     

Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) during winter in Dongzhai National Nature Reserve, Henan Province, China

Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001～2002 and 2002～2003 in the Dongzhai National Nature Reserve, Henan Province. Results from five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ± 1.17 hm² by Minimum Convex Polygon method, 8.60 ± 0.35 hm² by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm² by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core area of the home range was found to be 1.88 ± 0.37 hm². Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs), and restoring some parts of the large shrub area into forests.     

附子多糖FⅠ的分离纯化及部分理化性质研究

白附片经热水抽提、Sevag法脱蛋白、乙醇沉淀、DEAE-C32柱层析分离,再通过Sephadex G-200柱层析进一步纯化,得到一种纯白色粉末状多糖,糖含量为97%,平均分子量为2.6×105,熔点为270℃.经完全酸水解、薄层层析、红外光谱分析,证明为葡聚糖.