肠道菌群：肠道干细胞增殖分化的调节者

肠道干细胞(intestinal stem cells, ISCs)是肠道各类上皮细胞的来源,通过平衡增殖与分化维持肠道稳态。同时,肠道菌群及其代谢物在维持宿主肠道稳态中也发挥着重要作用。随着技术的发展,研究者认识到ISCs与肠道菌群之间存在相互作用。研究表明,ISCs对上皮细胞亚型的调控影响肠道菌群的组成,并且肠道菌群及其代谢物也影响ISCs介导的上皮发育。本文阐述了ISCs分化对肠道菌群的影响,重点总结了肠道菌群及其代谢物调控ISCs增殖分化的研究进展,从菌群调控ISCs的角度探讨肠道损伤的治疗思路,并对未来可能的研究方向进行讨论。     

Comprehensive Evaluation and Screening for 1,2,4-Trichlorobenzene Tolerance in Rice Cultivars at Different Growth Stages

Journal of Plant Growth Regulation - 1,2,4-trichlorobenzene (1,2,4-TCB) pollution in fields has become a potential threat to rice growth, yet little is known about the different response of many...     

广东四片藻鞭毛器的亚微结构和囊壳的形成

本文详细研究了1种海生4条鞭毛的单胞绿藻——广东四片藻鞭毛器的亚微结构和囊壳的形成。4条鞭毛着生于细胞前端凹陷的基部,鞭毛表面覆盖2层鳞片;基体呈纵向平行的“Z”字形排列;具纹纤维连接内外径向排列的两个基体;4个片层状的卵形盘(或称半桥粒(halfdesmosome))微管和纤维物质构成的复合体将鞭毛器和根丝体固着在质膜和囊壳上。根丝体通过两束交叉的微管带与两个邻近的外侧基体相连接。这种连接方式与其它已研究过的四片藻是不同的。囊壳的形成开始于内膜系统,特别是高尔基体。纤维丛和电子密集颗粒在其中合成、修饰,同时由高尔基体衍生的小泡转移到原生质体表面特定的区域,然后经若干步骤接合成完整的囊壳。这个区域与蛋白核的位置相关,表明聚合星状颗粒酶是在蛋白核位点制造或释放的,同时分泌到细胞外。囊壳沿边生长组装与细胞质发育产生特征性的前端鞭毛凹陷同时发生。     

运用分支系统学方法对逆珊瑚亚科的修订

运用分支系统学方法，考察有可能归入Ａｎｔｉｐｈｙｌｌｉｎａｅ亚科的各属。根据个体发育极向标准对选取的７个性状进行分析，这７个性状为：主隔壁的长短，主内沟的形状和大小，对隔壁的长短和加厚程度，侧隔壁的长度，一级隔壁的排列，一级隔壁从轴部退缩程度，轴部构造等。据以上各性状在每个属中的表现编制出性状极向数据矩阵，输入计算机运算，得到分支图。并得到以下结果：ＡｎｔｉｐｈｙｌｌｉｎａｅＩｌｉｎａ应包括下列１０属：ＡｃｔｉｎｏｐｈｒｅｎｔｉｓＩｖａｎｏｗｓｋｉ，１９６７；ＦａｌｓｉａｍｐｌｅｘｕｓＦｅｄｏｒｏｗｓｋｉ，１９８７；ＬｏｎｇｉｃｌａｖａＥａｓｔｏｎ，１９６２；ＬｙｔｖｏｌａｓｍａＳｏｓｈｋｉｎａ，１９２５：ＮｅｏｚａｐｈｒｅｎｌｉｓＧｒｏｖｅ，１９３５；ＭｏｎｏｐｈｙｌｌｕｍＦｏｍｉｃｈｅｖ，１９５３：ＦａｓｃｉｃｕｌｏｐｈｙｌｌｕｍＴｈｏｍｓｏｎ．１８８３：ＢｒａｄｙｐｈｙｌｌｕｍＧｒａｂａｕ．１９２８：ＲｏｔｉｐｈｙｌｌｕｍＨｕｄｓｏｎ，１９４２；ＣｌａｖｉｐｈｙｌｌｕｍＨｕｄｓｏｎ，１９４２。     

Cambrian lobopodians–ancestors of extant onychophorans?

This paper is a review of published information on fossil lobopodians, with addition of observations and ideas based on new material. It is also an analysis of the phytogeny of the group, and presents a new classification. A character shared by three or four families, yet not seen before, is a pair of enlarged sclerites covering the head. This forms an argument for re-orienting Hallucigenia once again. This genus no longer being enigmatic, a corner-stone in Stephen Jay Gould's evidence for extinct phyla is therefore gone. It is suggested that the lobopodians, phylum Lobopodia, are arranged in two classes, the extinct Xenusia for marine forms, and the Onychophora for terrestrial forms. The marine lobopodians are morphologically much more diverse than the extant onychophorans, a condition expressed in the classification. New taxa are: Hallucigenia fortis sp. nov., the families Luolishaniidae, Cardiodictyidae and Onychodictyidae, and the new orders Archonychophora, Scleronychophora and Paronychophora.     

桂东、桂东南晚泥盆世一个弗拉斯期放射虫动物群

本文系统描述了广西玉林、贺县等地晚泥盆世榴江组硅质岩中的放射虫化石4属14种,其中有1新属2新种。这个放射虫动物群的多数分子曾见于苏联南乌拉尔地区和澳大利亚的弗拉斯阶。     

中国南沙海区全新世小孔亚目(苔藓虫唇口目)的古生态研究

本文简要叙述南沙海区全新世小孔亚目苔藓虫群体形状和生态环境的关系,对非附着生长的类型进行了初步的分类。