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陈述了ISO9000质量管理体系在湖南省水文水资源勘测局的建立过程及带来的管理观念转变,分析了质量管理体系对本单位的利与弊。     

我国玻璃钢渔船发展历程及建造工艺技术

介绍了我国大陆及台湾玻璃钢渔船的发展历程及台湾玻璃钢渔船迅速发展所采取的措施,概要介绍我国玻璃钢渔船相关技术法规建设及真空树脂导入成型工艺技术的应用情况及存在的问题,探讨了今后的研究方向。     

中华绒螯蟹性腺发育的形态学、组织学和组织化学变化

以组织学、组织化学方法研究了中华绒螯蟹后期的性别分化过程。结果表明，中华绒螯蟹雌雄个体在此过程中形态学变化差异显著，雌蟹最宽腹节由第一节逐渐向第五节转变，雄蟹则始终为第三节；雄蟹最长腹节长与背甲长的比率随背甲的增大而减小，而雌蟹则相反，其形态上的差异可作为区分幼蟹性别的直观依据。卵巢从发生到成熟，其颜色由透明、白色、浅咖啡色、豆沙色至深豆沙色转变；精巢的发生则早于卵巢，当卵巢仅为原始生殖细胞团时，精巢已初步具有完整的形态，并且精子出现的时间早于成熟期初级卵母细胞。组织化学研究表明，在精子发生和成熟期卵母细胞形成过程中，都存在多糖类物质积累的过程，同时卵母细胞还进行蛋白质的积累，并且蛋白质的积累早于多糖类物质的积累。     

Effects of weaning age and diets on ontogeny of digestive activities and structures of pikeperch (<Emphasis Type="Italic">Sander lucioperca</Emphasis>) larvae

Growth and ontogeny of digestive function were studied in pikeperch (Sander lucioperca) larvae weaned on artificial food at different ages. Three weaning treatments initiated respectively on day 9 (W9), day 15 (W15) or day 21 (W21) post-hatching (p.h.) were compared with a control group, fed Artemia nauplii from first feeding until the end of the rearing trial on day 36 p.h. The digestive enzyme activities and the ontogeny of digestive structures were investigated using enzymatic assays and histological methods. Growth of pikeperch larvae was significantly affected by precocious weaning. Pancreatic (trypsin and amylase) and intestinal (leucine-alanine peptidase, leucine aminopeptidase N and alkaline phosphatase) enzyme activities were detected from hatching onwards, increased at the moment of first feeding and then decreased. Pepsin secretion occurred at day 29 p. h. only, concurrently with the stomach development and differentiation of gastric glands. In the early weaning group (W9) the maturation process of intestinal enterocytes seems to be impaired and/or delayed and several signs of malnutrition were recorded. Except for alkaline phosphatase activity, no differences in enzyme activities and development of digestive structures were observed among the control, W21, and W15 groups. Moreover, at the end of the experiment, no differences in proteolytic activities were observed among larvae from the different treatments, indicating that, in surviving individuals, the digestive structures were properly developed and the larvae had acquired an adult mode of digestion. Based on the artificial diet used, our results suggested that pikeperch larvae can be weaned from day 15 p.h. without significant adverse effect on digestive capacities (except for alkaline phosphatase) or development of digestive tract, while earlier weaning impaired the onset of the maturation processes of the digestive system, both in terms of morphological structures and enzymatic activities.     

Wetlands: conservation's poor cousins

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