秦岭滑蜥排泄系统组织形态学观察

运用大体解剖和组织切片技术对秦岭滑蜥Scincella tsinlingensis排泄系统进行了组织形态学观察。结果显示:秦岭滑蜥的排泄系统包括肾脏、输尿管、膀胱和泄殖腔。肾脏由被膜与实质构成,实质包括许多泌尿小管与少量结缔组织。泌尿小管包括肾单位与集合管,肾单位的数量较两栖类有了明显增加。结缔组织中分布有少量弹性纤维、网状纤维和大量胶原纤维。输尿管由许多分支的集尿管汇聚形成,包括黏膜与外膜,黏膜由单层柱状上皮过渡为多层鳞状细胞,固有层零散分布有浆细胞,结缔组织中分布有胶原纤维与少量弹性纤维。膀胱由黏膜层、肌层与外膜构成,黏膜上皮为变移上皮,固有层分布有少量的浆细胞。消化道、生殖道和输尿管末端汇聚于泄殖腔,泄殖腔壁由黏膜、肌层和外膜构成,黏膜上皮分布有黏液性细胞和少量浆细胞。秦岭滑蜥的排泄系统与其他卵胎生蜥蜴无明显差别。     

尾斑瘰螈泌尿器官的形态组织学观察

本文采用组织学和形态学方法对尾斑瘰螈的泌尿器官进行研究。结果表明:尾斑瘰螈的泌尿器官主要包括肾脏、输尿管和膀胱。其肾脏为实质性器官,主要由肾小体、肾小管构成;肾实质出现区域分隔,肾小体数量较少,肾小管分为颈段、近曲小管、中间段、远曲小管;其间未发现淋巴组织以及与生殖有关的结构。输尿管由单层立方上皮过渡到假复层立方上皮;膀胱壁由2~3层细胞变移上皮构成。     

香鱼消化道及肝脏的形态结构特征

采用解剖及石蜡切片显微技术观察了香鱼消化道及肝脏的组织学结构。香鱼消化道由口咽腔、食道、胃及肠构成。口咽腔大且狭长,其底壁前部有一对粘膜褶,两颌边缘着生宽扁梳状齿,腭骨及舌骨具齿,犁骨无齿;舌由基舌骨突出部分覆盖粘膜构成,舌粘膜上皮为复层扁平上皮,含有较多的杯状细胞和味蕾。食道、胃及肠均由粘膜层、粘膜下层、肌层及外膜构成。食道粘膜层上皮为复层扁平上皮,杯状细胞发达。胃呈V形,由贲门部、胃体部及幽门部组成,胃壁粘膜上皮为单层柱状上皮,贲门部与胃体部的固有层中有胃腺。肠较短,由前、中、后肠构成,肠壁粘膜上皮为单层柱状上皮,其游离面具微绒毛;上皮细胞间有杯状细胞。幽门盲囊有350～400条,其组织学结构与肠相同。肝脏单叶,外被浆膜;肝细胞形态不规则,肝小叶界限不明显。     

小熊猫胃的解剖和组织结构研究

小熊猫的胃属单室腺型胃,它以角切迹为界,可分为胃底部和幽门部两部分.胃壁由粘膜、粘膜下层、肌层和浆膜四层组成.四上皮为单层柱状上皮,具有分泌粘液的功能.胃腺有贲门腺、胃底腺、幽门腺三种,但贲门腺不发达.主细胞、壁细胞和粘液细胞的数量与分布呈现规律性变化.肌层发达,特别是内环行肌发达.并与大熊猫胃的结构作了比较.     

白鱀豚甲状腺及甲状旁腺的初步研究

本文是8头白鱀豚(Lipotes vexillifer)的甲状腺及甲状旁腺的初步研究结果。白鱀豚甲状腺的解剖学和组织学结构与其它海豚相似。其甲状腺滤泡呈圆形或椭圆形,滤泡胶质嗜酸性,滤泡平均直径为106.4微米,滤泡上皮平均高为9.4微米,滤泡旁细胞平均直径为11.0微米。甲状旁腺分布在甲状腺的腹侧面或前、后方,其上皮细胞被结缔组织分隔成团索状。文中并讨论了白鱀豚甲状腺的一些组织形态变化。       

白鱀豚甲状腺及甲状旁腺的初步研究

本文是8头白鱀豚(Lipotes uexillifer)的甲状腺及甲状旁腺的初步研究结果。白鱀豚甲状腺的解剖学和组织学结构与其它海豚相似。其甲状腺滤泡呈圆形或椭圆形,滤泡胶质嗜酸性,滤泡平均直径为106．4微米,滤泡上皮平均高为9．4微米,滤泡旁细胞平均直径为11．0微米。甲状旁腺分布在甲状腺的腹侧面或前、后方,其上皮细胞被结缔组织分隔成团索状。文中并讨论了白鱀豚甲状腺的一些组织形态变化。     

鲫鱼松果体的显微和超微结构研究

本文作者发现鲫鱼的松果体与一般硬骨鱼不同,它除由背囊和背囊内褶中松果管所组成的松果体外,还有退化的旁突体和副松果体.背囊是单层柱状纤毛上皮,其腔与第3脑室相通,松果管由光感觉细胞、支持细胞、节细胞、丰富的血管和无髓神经纤维构成.松果体既是光感受器又有内分泌的功能.       

长蛸生殖系统的形态学与组织学观察

运用解剖学和组织学方法对长蛸(Octopus variabilis)生殖系统的形态结构进行了研究.结果表明,长蛸雌雄异体并异形,雄性右侧第三腕茎化.长蛸雌性生殖系统由一个卵巢、成对的输卵管及输卵管腺组成.卵巢壁上发出一条线状具分支的生殖索,米粒状的滤泡以卵柄连接至生殖索上.每个滤泡是由单层滤泡细胞围绕着一个卵母细胞构成.输卵管形成丰富的纵行褶皱,黏膜上皮具有纤毛.输卵管腺含有两种类型腺细胞.雄性生殖系统包括精巢、输精管前段、储精囊、摄护腺、盲囊、输精管后段和精荚囊.精巢内部被结缔组织分隔成许多精小叶,精原细胞由小叶壁中的生殖上皮产生,并向小叶腔中逐步分化成精子.输精管前段、盲囊和摄护腺所分泌的黏液物质共同参与精荚的形成.储精囊和输精管后段形成较多的纵行褶皱,输精管后段上皮游离面的纤毛可运输生殖细胞.精荚囊的作用则是贮存精荚,囊壁中的平滑肌利于长蛸交配时精荚的排出.     

鲻鱼甲状腺免疫组织化学与超微结构

用组织学、免疫组织化学和电镜技术对鲻鱼甲状腺的分布与形态结构进行研究。结果表明，鲻鱼甲状腺滤泡分散地分布在第1对至第3对鲻弓的入鳃动脉之间；构成同一滤泡的单层上皮细胞呈扁平形和立方形两种形态，反映出同一滤泡中上皮细胞生理活动的不同步，且发现不同发育时期的鲻鱼这两种形态细胞的比例有显著差异。用特异性甲状腺球蛋白(TG)抗体对甲状腺滤泡的免疫染色反应显示，阳性物质分布在滤泡上皮细胞的脑膜及围绕滤泡腔的周边与中央胶质，幼年与成年鲻鱼甲状腺滤泡的免疫阳性反应部位有所不同。两种不同活动状态的细胞，扁平形细胞和立方形细胞，在核与胞质的超微结构上有显著不同。扁平形细胞的核为扁平形或椭圆形，核内常染色质十分丰富，核膜光滑，核周腔和核孔没有扩张，胞质中各种细胞器发育较差；立方形细胞的核膜高度凹陷，将核分为2叶至3叶，核周腔和核孔扩张，胞质中各种细胞器发育良好，出现长棒形和哑铃形线粒体，且数量明显多于扁平形细胞，多层粗面内质网呈板层状排列，还有发育好的高尔基复合体。另外，我们还观察到一种介于扁平形细胞和立方形细胞之间的中间型细胞，其胞质和核的发育明显好于扁平形细胞，但比立方形细胞差。上述结果可为了解鲻鱼甲状腺滤泡细胞分泌活动的机制提供基础资料[动物学报49(2)：230—237，2003]。     

九孔鲍卵子发生及卵巢发育的组织学观察

采用组织学方法研究了九孔鲍(Haliotis diversicolor supertexta)的卵子发生、卵巢结构及其发育.根据卵细胞的大小、形状,核仁的形态,卵黄颗粒的积累情况,滤泡的结构等.将九孔鲍卵子的发生分为卵原细胞、卵黄发生前的卵母细胞和卵黄发生期的卵母细胞3个时期;卵巢壁由外膜及内生殖上皮构成,生殖上皮分化产生卵原细胞和滤泡细胞;卵巢的结构单位是滤泡.根据卵巢的外部形态和内部组织结构,将九孔鲍的卵巢发育分为休止期、增殖期、生长期、成熟期和排放期共5期.     

On the origin of the Hirudinea and the demise of the Oligochaeta

The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.     

On the ontogeny of the haptor and the evolution of the Monogenea

Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor