昆虫的雌雄嵌合现象

探讨了昆虫雌雄嵌合体的类型、类群、发生机制、对昆虫生物学的影响 ,以及其在胚胎发育学、比较形态学、神经系统调控机理上的应用。并对 1 980～ 2 0 0 0年《动物学记录》中收入的雌雄嵌合体记录进了行整理 ,共发现 1 3目 69科昆虫有雌雄嵌合体记载。

087鼻皮样囊肿和窦道

本文简述了鼻皮样囊肿和窦道的胚胎发育学，临床表现，影像诊断及手术治疗。

An extra embryonic phase in the true freshwater crab Sinopotamon yangtsekiense Bott,1967(Decapoda,Potamidae)

The true freshwater crabs(Crustacea,Decapoda,Brachyura) are highly adapted to life in freshwater and complete their life cycle entirely independently of sea water.All true freshwater crabs exhibit direct development and lack the free-living larval forms(zoea and megalopa) typical of most other brachyurans.After a prolonged embryonic period(during which they pass through the typical brachyuran larval forms embryologically) the eggs of true freshwater crabs hatch to produce juvenile(hatchling) crabs.We provide here the first report and description of the continuous record of embryonic development from egg-laying up to hatching in the Chinese true freshwater crab Sinopotamon yangtsekiense Bott,1967(Potamoidea,Potamidae).Direct development(complete secondary embryonization) in S.yangtsekiense was observed to take 77 days and to include an additional embryonic phase(termed here the egg-juvenile-crab) that occurs in the embryo between the imprisoned megalopa and the newly-emerged juvenile(hatchling) crab.This is significant because the only other freshwater crab whose embryonic development has been studied in detail is Potamon fluviatilis(Potamidae) which takes 45-47 days and involves only nine embryonic stages.

Polyploidy induction by hydrostatic pressure shock and embryo development of sea cucumber Apostichopus japonicus

The manipulation of the chromosome set for commercially valuable marine animals is important for enhancing aquacultural production. In this study, triploid and tetraploid sea cucumber Apostichopus japonicus were induced by hydrostatic pressure shock, and the conditions of appropriate induction were tested with different starting times, and hydrostatic pressure intensities and durations. The highest rate of triploid induction reached 20% and that of tetraploid was 60%. In consideration of the survival rate and hatch rate, the appropriate treatment for triploid was 55 Mpa of hydrostatic pressure for 5 rain at 55 min after fertilization （a.f.）, while for tetraploid it was 60 Mpa for 5 rain at 61 min a.f. The triploid of the sea cucumber could survive through the pelagic larval stage and attachment stage, and develop like the control group of the experiment. The tetraploid, however, could not survive the attachment stage.

层次解剖：再谈腹部外科这一古老的解剖概念

层次解剖是一个既古老又新颖的词汇，最早衍生于局部解剖的概念。层次解剖是基于局部解剖及胚胎发育生物学而来的概念。随着腹腔镜及机器人等外科手术设备的发展，要求外科手术出血量更少、解剖更精细、术后恢复更快、复发率更低等。因此，层次解剖再次被外科医师重视。腹腔内的各个脏器均是由不同层次结构的不同组织构成，其间多是结构疏松并乏血管的结缔组织。按照层次进行解剖，可以避免外科学上缺少解剖概念的“整块”切除，而达到完全切除病灶和保护周围正常组织免受损伤的最好手术效果。

大鼠神经干细胞体外培养及分化

神经干细胞的研究是最近几年来神经科学及胚胎发育学的热点问题。人们通常认为成年哺乳动物的中枢神经系统组织是不可再生的，中枢神经系统损伤或神经系统退行性病变将只能由神经胶质爬行替代，遗留难以弥补的神经系统功能缺损。而神经千细胞特别是在成年哺乳动物中枢神经系统中发现的神经千细胞对以上观点产生了巨大的冲击。随着神经干细胞的研究深入，必将为神经系统损伤性、退行性疾病的彻底治愈，甚至神经移植治疗带来一次革命性突破。

Significant variations in alternative splicing patterns and expression profiles between human-mouse orthologs in early embryos

Human and mouse orthologs are expected to have similar biological functions; however, many discrepancies have also been reported. We systematically compared human and mouse orthologs in terms of alternative splicing patterns and expression profiles. Human-mouse orthologs are divergent in alternative splicing, as human orthologs could generally encode more isoforms than their mouse orthologs. In early embryos, exon skipping is far more common with human orthologs, whereas constitutive exons are more prevalent with mouse orthologs. This may correlate with divergence in expression of splicing regulators. Orthologous expression similarities are different in distinct embryonic stages, with the highest in morula. Expression differences for orthologous transcription factor genes could play an important role in orthologous expression discordance. We further detected largely orthologous divergence in differential expression between distinct embryonic stages. Collectively, our study uncovers significant orthologous divergence from multiple aspects, which may result in functional differences and dynamics between human-mouse orthologs during embryonic development.

Germ layer formation during Xenopus embryogenesis: the balance between pluripotency and differentiation

The African clawed frog, Xenopus laevis, has long been a model animal for the studies in the fields of animal cloning, developmental biology, biochemistry, cell biology, and physiology. With the aid of Xenopus, major molecular mechanisms that are involved in embryonic development have been understood. Germ layer formation is the first event of embryonic cellular differentiation, which is induced by a few key maternal factors and subsequently by zygotic signals. Meanwhile, another type of signals, the pluripotency factors in ES cells, which maintain the undifferentiated state, are also present during early embryonic cells. In this review, the functions of the pluripotency factors during Xenopus germ layer formation and the regulatory relationship between the signals that promote differentiation and pluripotency factors are discussed.

Transparent soft PDMS eggshell

In vivo 3D fluorescent image remains a technological barrier for biologists and clinical scientists although green fluorescent protein(GFP)imaging has long been performed rather well at cellular level.Meanwhile,robust enough portable devices are also challenging lab-on-a-chip advocators who wish their designs to be nurtured by the end users.This work is dedicated to propose a conceptually innovated transparent soft PDMS avian eggshell to directly tackle the above two goals.Here,an"egg-on-a-chip"scheme is originally developed and demonstrated by a newly developed PDMS"soft"process method.Unlike its ancestor–the conventional"lab-on-a-chip"(LOC)which is basically chemically based,the current"egg-on-a-chip",intrinsically inherited with biological natures,opens a way to integrate biological parts or whole system in a miniature sized device.Such biomimics system contains much condensed environmental evolutional tensor inside than those of the existing LOC compacted with artificial components which however are quite difficult to incorporate various life factors inside.Owning unique advantages,a series of transparent PDMS whole"eggshells"have been fabricated and applied to culture avian embryos up to 17.5 days and chimeric eggshells were engineered on normal eggs.In addition,X-stage embryos were successfully initiated in such system and pre-chorioallantoic membrane was observed.Further,limitation of the present process was interpreted and potential approach to improve it was suggested.With both high optical transparency and engineering subtlety fully integrated together,the present method not only provides an ideal transparent imaging platform for studying functional embryo development including life mystery,but also promises a future strategy for"lab-on-an-egg"technology which may be important in a wide variety of either fundamental or practical areas.