The phytogeographical studies of Thermopsis (Fabaceae)

The present article is the first comprehensive treatment of phytogeography of Thermopsis (Fabaceae) in the world. Thermopsis is one of the few genera within Fabaceae with the distribution pattern of the East Asia-North American disjunction. The distribution patterns of 5 recognized sections (including a new one) covering 21 species in Thermopsis are analyzed, and the results show four centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4 endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), the Rocky Mountain Region (7 spp./2 sects., all endemic), and the Atlantic North American Region (3 spp. / 1 sect., all endemic). In the light of the fact that most species and sections, a number of phylogenetic series of the genus, and the most primitive sections and most advanced sections in Thermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of the genus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that of Eastern Asiatic Region in number of sections and species, and many polyploids appeared in these regions, they were considered as the secondary centres of distribution and speciation of the genus. The speciation looks to be frequent and complex in these regions, and many new taxa have been described from there while many new reduced or incorporated taxa have happened over there. However, recent molecular data has shown that two reduced taxa of Thermopsis are distinct in these regions. Based on the modern distribution patterns and evolutionary trends in morphological characters of the genus, and available fossil record of the genus and the historical geology, we speculate that Thermopsis had already existed on Eurasia and North America before the Late Miocene, and probably originated from an ancestral form of Sophora-like taxa with lupine alkaloids somewhere in the Laurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, species on different continents developed distinctly under influences of different evolutionary factors. In Asia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by the Quaternary glaciation were the main forces to promote the speciation and evolutionary processes, whereas in North America it was the Quaternary glaciation and the orogeny of partial area to promote evolution of the genus. According to the evolutionary trends in Thermopsis and the distribution pattern of the primitive taxa, Sino-Japanese Subregion of Eastern Asiatic Region may be considered asthe centre of primitive forms of Thermopsis.     

人TRAIL基因cDNA的克隆及其在COS-7细胞中的表达

TRAIL(TNF-related apoptosis inducing ligand)是最近克隆的肿瘤坏死因子(TNF)家族的新成员,由于它的蛋白质结构和生物学效应类似于FAS/APO-1L,因此,也被称为APO-2L.     

非酒精性脂肪肝大鼠脂质代谢及病理变化的动态观察

目的通过高脂饮食建立NAFLD大鼠模型,连续监测4～16周模型动物肝功能、脂质代谢、胰岛素抵抗及肝细胞凋亡在NAFLD进展过程中的变化情况及相互关系,为该模型在脂肪肝发病机制、脂肪肝治疗药物评价等方面的应用提供参考依据。方法 SD大鼠50只,除正常对照组外,其余动物饲喂高脂饲料,分别检测4,8,12,16周大鼠血清GLU、CHO、TG、HDL、LDL、GPT、GOT及胰岛素水平,肝脏组织切片进行病理学及细胞凋亡观察,进一步分析大鼠肝功能、脂质代谢、胰岛素抵抗及肝细胞凋亡对肝组织病理改变的影响。结果模型组大鼠4周后就出现肝功能损伤,脂质代谢紊乱、胰岛素抵抗,肝细胞凋亡8 W后明显增加,肝细胞脂变及炎症为肝组织病理变化的主要特征,且造模时间越长,病变程度越严重。结论经过高脂饲料的喂养,SD大鼠在4～16周内可形成病变程度逐步加重的NAFLD模型,肝功能损伤,脂质代谢紊乱及肝细胞凋亡是引起非酒精性脂肪肝中脂肪变性和炎症的重要因素,该模型可应用于脂肪肝治疗药物评价等方面。     

几种旱生灌木种子萌发对干旱胁迫的响应

以不同渗透势的PEG(6 0 0 0 )溶液 (- 0 .3～ - 2 .7MPa)为模拟干旱胁迫条件 ,研究了柠条 (Caraganakorshinskii)、花棒 (Hedysarumscoparium)和白沙蒿 (Artemisiasphaerocephala)种子发芽、幼苗生长和累积吸水率对干旱胁迫的响应 ,讨论了参试种子发芽特性、初生根长度与幼苗建植成活率的关系 .结果表明 ,干旱胁迫下柠条发芽率最高 ,其次为花棒 ,白沙蒿最低 . - 0 .3～ - 0 .6MPa渗透势下白沙蒿发芽 10d的初生根长度显著大于花棒和柠条 (P <0 .0 5 ) ,三者的测量值依次为 7.9、4 .5和 3.1cm .干旱胁迫条件下参试种子发芽率与种子 72h累积吸水率均呈极显著的正相关 (P <0 .0 1) .     

以疏勒河流域为例的“山水林田湖草”生态修复多尺度耦合框架及方法

为解决过去保护修复工程只考虑单要素、单一类型生态系统的问题,我国于2016年开展了“山水林田湖草”生态修复工程,旨在通过整体、系统、综合的方法对各类生态系统进行统筹治理。然而,目前的工程治理中仍然存在对系统内部及系统间耦合概念理解不充分、系统耦合机制不明晰、对“尺度”的关注不足、缺少科学的分析方法等问题,制约了保护修复的成效。对此,首先将多个尺度下的耦合研究方法进行归纳总结,并以国家重点冰川水源涵养区及生物多样性保护优先区——疏勒河流域为例,将耦合方法用于分析要素间、自然生态系统间的耦合关系,最后基于该实例研究,提出多尺度耦合分析框架与“升尺度”保护修复模式,以期帮助相关决策者明晰“山水工程”中要素、系统间的耦合关系,增强治理的科学性与有效性,进而推进我国社会与环境的可持续发展。     

未净化Z：ZCLA长爪沙鼠封闭群繁育及遗传稳定性分析

目的分析未净化Z：ZCLA长爪沙鼠封闭群繁育和生长指标,并利用直接测序法分析其遗传稳定性。方法随机选择40对Z：ZCLA长爪沙鼠,记录其繁殖胎次、产子数等指标,分析其仔鼠的生长发育情况。遗传稳定性分析选择Z：ZCLA长爪沙鼠非同胞、非亲代个体33只,提取肝脏基因组DNA,PCR扩增D-Loop序列,产物纯化后双向测序,测序结果与Z：ZCLA长爪沙鼠标准序列比对。结果 Z：ZCLA长爪沙鼠每胎产仔7只,胎间隔多在20～60 d间,雄性体重高于雌性。遗传稳定性分析检测发现33只Z：ZCLA长爪沙鼠序列与标准序列完全一致。结论 Z：ZCLA长爪沙鼠群体内未发现遗传多态性,说明该群体具有较好的遗传稳定性。     

大兴安岭南部山地苔藓植物区系多样性研究

于2009～2012年对大兴安岭南部山地6个自然保护区的苔藓植物进行了野外实地调查,对所采集的1 800余号标本进行室内分析鉴定,并计算分析其种类组成、区系地理成分、地区之间相似性系数和相异系数的欧氏距离比较,及其8种生境中苔藓植物多样性指数、丰富度指数、均匀度指数和优势度指数等,为保护区的管理和建设提供基础资料。结果表明:(1)大兴安岭南部山地6个自然保护区共有苔藓植物48科,134属,330种,其中苔类16科,21属,38种,1变种;藓类32科,113属,274种,14变种,2变型,1亚种。(2)首次发现中国新记录4种:长柄紫萼藓(Grimmia longirostris Hook.),毛尖连轴藓[Schistidium lancifolium(Kindb.)Blom.],平叶真藓(Bryumlaevifilum Syed.),凹叶毛灰藓[Homomallium adnatum(Hedw.)Broth.],首次发现本地区新记录12种。(3)以丛藓科为代表的旱生藓类在本区占有优势地位;区系地理成分以温带成分(60.79%)和东亚成分(16.19%)为主。(4)大兴安岭南部山地与兴安北部和燕山北部山地亲缘关系较近;生境条件的变化对苔藓植物多样性产生了一定的影响,湿润土生和石生生境为本区苔藓植物最丰富的生境,水生生境中苔藓植物分布最少。研究发现,大兴安岭南部山地苔藓植物区系是连接华北区、东北区、蒙新区和阴山地区的过渡性地带;与燕山北部和兴安北部相比,大兴安岭南部山地大面积苔藓植物地被层分布较少的主要原因是森林密度和湿度较低。因此,建立保护区对保护大兴安岭南部山地脆弱的森林、草原过渡生态系统,保护中国野生动植物类群及其他珍稀动植物的繁衍均具有十分重要的意义。