Reproductive biology of two species of Hyalella Smith, 1874 (Crustacea: Amphipoda: Hyalellidae) from southern Brazil

Reproduction is a critical event in the life cycle of animals, and a high amount of energy is allocated to it. The aim of this study was to characterize the reproductive biology of two recently described species of Hyalella from the north-east region of state of Rio Grande do Sul in southern Brazil. The specimens were collected during 12 months from a stream source (Hyalella georginae) and from a water reservoir (H. gauchensis), in Palmeira das Missões municipality, state of Rio Grande do Sul. Upon sampling, ovigerous females and pairs in precopulatory behaviour were separated into microtubes. In the laboratory, the cephalothorax length (CL in mm) of all specimens was measured. Male size at onset of sexual maturity was larger than that of the females, in both species. There was a correlation between the size of paired males and females: larger males carried larger females, in both Hyalella species. Precopulatory pairs were found throughout the year; however, H. georginae had a higher frequency in spring, and H. gauchensis in autumn. There was a positive correlation between the CL of ovigerous females and the number of eggs/juveniles. A reduction in the number of eggs throughout the embryonic development was observed in H. georginae. The average fecundity of H. georginae was significantly higher than H. gauchensis. The differences between the reproductive biology of these species may be related to the physical and environmental conditions at which they are exposed in their habitats.     

Caecilian viviparity and amniote origins

A recent evaluation of alternative hypotheses for the origin of the amniotic egg, by mapping a single reproductive-mode character onto a phylogeny of tetrapods, concluded that the alternative hypotheses were equally parsimonious. However, this interpretation is dependent upon a mistaken coding of the caecilian amphibians as showing extended embryo retention. Although some caecilians are viviparous, phylogenetic analyses indicate that oviparity is ancestral for the group. With the coding of caecilians corrected, the most parsimonious inference is that the ancestral amniotes did not practice extended embryo retention. A review of the available data indicates that the widespread view that a majority of caecilians are viviparous is mistaken. Oviparity is the dominant reproductive mode in caecilians as it is in other living amphibians.     

颅脑损伤昏迷患者肠内营养并发症的预见性护理

目的：探讨颅脑损伤昏迷患者肠内营养并发症的预见性护理.方法：对2010-10～2011-02内蒙古民族大学附属医院神经外科收住的29例颅脑损伤患者肠内营养并发症的预防及护理进行回顾性分析总结.结果：27例患者好转出院,2例自动出院,评估患者胃肠功能正常,机体营养状况良好.结论：预见性护理可以有效减少颅脑损伤昏迷患者肠内营养并发症的发生,使肠内营养支持顺利进行,有效减轻机体损耗,从而降低颅脑损伤患者的病死率及病残率.     

A new species of Crepidula (Mollusca: Mesogastropoda: Calyptraeidae) from Chile: additional characters for the identification of eastern Pacific planar Crepidula group

A new species of Crepidula is described. It was collected together with Pagurus edwardsii Dana and Pagurus perlatus H. Milne Edwards, inhabiting the inside of empty shells of Tegula euryomphala Jones and other gastropods. The shell is low convex-oval in juveniles, low convex-oblong in males and concave-oblong elongated in females. In the adult phases the apex projects slightly at the posterior border. The sinusoidal septum is ‘V’ shaped at its centre, with a smooth sulcus in the left quarter. The osphradium has 2–13 digitiform leaflets according to phases of the life cycle. The characteristically thin, external-lateral teeth of the taenioglossate radula possess a row of denticles. In addition, evidence is given that: (1) males have a lanceolate penis with a spermatic tube; (2) the intracapsular-embryonic development starting with many embryos, occurs with a decrease at the larvae-protoconch stage, each one with an adhered-vitelline mass, and culminates with a few prehatching juveniles of 1 mm size. In the expression of the consecutive-protandric hermaphroditic sexuality, the male phase is truly separated from the female phase by a transition period at the population level. The shell and radular morphology, intracapsular development and ecological antecedents allow the proposal of Crepidula coquimbensis as a new species, and suggest a future taxonomic revision of the group based, moreover, on osphradium structure and new characters of the reproductive system, such as penis morphology.     

草原沙晰（Phyrnocephalus frontalis）生殖策略的研究

草原沙晰（Phyrnocephalus frontalis）每年产卵一次，平均窝卵数为3，平均生殖投入（卵重／体重）为0.164，生殖投入与体长、体重、年龄不相关；窝卵数与生殖投入显著正相关，y=0.025x 0.095,r=0.462，即生殖投入随窝卵数增加而增加；体重与窝卵数显著正相关y=0.35x 0.86,r=0.65；体长与窝卵数刀显著正相关，y=0.1x-2.45,r=0.51。根据繁列期前后性比（♀/♂）的变化，推测部分雌晰繁殖后死亡，说明生殖对雌性有一定的损害作用，根据各项生态学特征的比较，草原沙晰的繁殖策略属K选择。     

营养元素调控热休克蛋白研究进展

热休克蛋白(Heat Shock Protein,HSP)是生物体在受热或其他不利环境因素刺激下应激合成的一组特殊蛋白质.HSP的生物学功能广泛,不仅表现在热应激条件下参与细胞的抗损伤、修复和热耐受过程,保护细胞生命活动,而且在蛋白质折叠、跨膜运输、细胞骨架及核骨架稳定等方面发挥重要作用.由于机体的营养状况与应激能力密切相关,本文主要综述了营养元素对HSP合成的调控作用.     

食管贲门癌术后吻合口瘘的介入置管肠内营养支持

自１９９２年７月至１９９８年２月７例食管癌贲门癌术后吻合口瘘治疗中，通过Ｘ线透视监视，经鼻将营养管置入肠内以建立营养通路，从而提供肠内营养支持，结果６例治愈，成功率８５．７％。本文介绍置管及营养补给方法及效果，指出本方法在营养支持治疗上更简便、有效且经济。     

冬季培养花鲈仔稚幼鱼饵料及其营养强化的初步研究

采用自选单胞藻代替小球藻调节育苗池水质和对轮虫，卤虫营养强化；控制水温15－20℃，光照4400Lux以上，换水20－30％等培养轮虫；以及按卤虫总量的2．5－3．0％的浓鱼油胶丸营养强化卤虫等技术措施，使仔稚幼鱼从0龄至47日龄存活率达到64．80％以上，47日龄至90日龄存活率达到80．71％。     

哺乳期营养状况对小鼠性发育启动时间的影响

选用近交系BALB/c小鼠,按每只母鼠哺乳出生后小鼠数量的多少分成营养过剩、营养均衡和营养不良3组,研究哺乳期营养状况对小鼠性发育启动时间的影响,以阴门开启和阴茎包皮分离分别作为雌鼠和雄鼠性发育启动的指标。雌小鼠性发育启动年龄:营养过剩组<营养均衡组<营养不良组(P<0.002),但是,3组小鼠性发育启动时的体重没有明显差异。雄小鼠性发育年龄:营养过剩组<营养均衡组<营养不良组(P<0.01);而发育时体重:营养过剩组>营养均衡组>营养不良组(P<0.01)。哺乳期营养状况对小鼠性发育启动时间有重要影响,但影响方式存在性别差异。     

人体饮食营养配餐决策支持系统的研究与实现

介绍了营养配餐DSS(DecisionSuportSystem)的国内外现状，探讨了营养配餐的数学模型、人体饮食营养配餐DSS的实现，总结了它的意义和应用前景．主要内容有单目标与多目标数学模型、营养评价、数据流图、总体结构等．该系统对于帮助人们合理饮食、增强体质有重大的现实意义，也有很大的经济效益和社会效益．