Effects of Sewage on the Chemical Composition of Piracicaba River,Brazil

Water samples were collected from 7 locations along major rivers of Piracicaba River basin for 22 months. The 4 upstream points represent non-polluted sites and the 3 downriver points represent polluted sites. Due to sewage input, concentrations of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), major conservative cations and anions increased significantly in the polluted sites. The major increases were observed for sodium, chloride and sulfate. Nitrate was an exception for this pattern, with similar concentrations between polluted and non-polluted sites. The probable cause was reduction of nitrate to ammonium in the polluted sites, where anoxic conditions prevail. Most of the variables had an inverse correlation with water discharge, especially in the polluted points. The sewage load was diluted by precipitation and surface waters.     

Influence of inorganic and organic fertilization on soil microbial biomass, metabolic quotient and heavy metal bioavailability

 We studied the long-term effects (12 years) of municipal refuse compost addition on the total organic carbon (TOC), the amount and activity of the microbial biomass (soil microbial biomass C, B_C and metabolic quotient qCO₂) and heavy metal bioavaiability in soils as compared to manuring with mineral fertilizers (NPK) and farmyard manure (FYM). In addition, we studied the relationships between among the available fraction [Diethylenetriaminopentacetic acid (DTPA) extractable] of heavy metals and their total content, TOC and B_C. After 12 years of repeated treatments, the TOC and B_C of control and mineral fertilized plots did not differ. Soils treated with FYM and composts showed a significant increase in TOC and B_C in response to the increasing amounts of organic C added. Values of the B_C/TOC ratio ranged from 1.4 to 2, without any significative differences among soil treatments. The qCO₂ increased in the organic-amended soil and may have indicated microbial stress. The total amounts of metals in treated soils were lower than the levels permitted by the European Union in agricultural soils. DTPA-extractable metals increased in amended soils in response to organic C. A multiple regression analysis with stepwise selection of variables was carried out in order to discriminate between the influence exerted on DTPA-extractable metals by their total content, TOC and B_C. Results showed that each metal behaved quite differently, suggesting that different mechanisms might be involved in metal bioavailability Received: 31 October 1997     

农用运输车可靠性分析评价研究

以ＹＬ２２０８ＣＷ型四轮农用运输车可靠性试验为依据,参照有关的国家和前机械工业部标准,对该车可靠性进行了分析,计算和评价,并开发了农用运输车可靠性评价计算机系统,提出了提高和改进其可靠性的途径。     

细粒棘球蚴细胞系(13G-5)细胞代谢抗原的免疫原性和反应原性

应用培育成功的人源细粒棘球蚴细胞系(13G-5)细胞的天然代谢抗原,接种昆明小鼠,于接种后第14天给免疫小鼠接种人源细粒棘球蚴原头节约1 000 个,于200 d 剖检观察有无包囊形成,病理切片鉴定;并用该抗原作为诊断抗原,使用间接血凝(IHA)、琼脂扩散(AGD)试验,检测临床确诊的细粒棘球蚴病人血清。以多房棘球蚴病人血清、细颈囊尾蚴羊血清及正常人血清作为对照。结果表明,该抗原能使60% 的小鼠获得完全抵抗细粒棘球蚴原头节攻击的能力,未完全获得保护的小鼠形成包囊的数量、大小较对照组明显减少,且为不育囊;使用该抗原IHA 检测31 份血清,阳性24 份,阳性率77.42% ,AGD检测30 份血清,阳性13 份,阳性率43.33% ,2 种方法对多房棘球蚴病人血清和细颈囊尾蚴羊血清及正常人血清不起反应。     

Reovirus serology in broiler parents and their progeny and its correlation with performance.

An intensive vertically integrated monitoring program for broiler breeders and their offspring was set up in a Belgian poultry integration between 1993 and 1997. Serology for anti-reovirus antibodies was performed by enzyme-linked immunosorbent assay on blood samples taken from the broiler parents throughout rearing and production and also on blood samples taken at day-old and at slaughter from the broilers. Furthermore, production parameters of the birds were registered. All data were used two by two in a simple correlation study to calculate the degree to which these variables were linearly correlated. The reovirus antibody pattern indicated frequent field infections breaking through vaccinal immunity in the broiler parents. Under the epidemiologic conditions of this study, high antibody titers in the parents or in the broilers at day-old were significantly correlated with poor feed conversion, increased mortality, increased slaughterhouse condemnation, and low production score in the broilers. These correlations strongly support the view that reovirus infections can be economically important under European conditions of broiler production. Improvement of reovirus vaccines or the vaccination scheme in broiler parents or both may lead to better production results in the broiler offspring.     

梅花鹿幼鹿人工培育技术的研究

本试验首先通过幼鹿日粮调配寻求最佳合理的日粮配合,首次制定出了幼鹿发育阶段精料年供量曲线。通过对幼鹿采用直线培育措施,加强饲养管理,取得了显著的效果。其中日增重提高３５ ％ ,初角茸产量提高了３ 倍,头锯茸产量提高了７７－９ ％ ,创造了历史最高产,幼公鹿出生５ 个月开始产茸,幼母鹿培育至１７ 个月即可参加配种,配种准胎率１００ ％ ,仔鹿成活率达到９２ ％ 。     

河水氨污染急性死鱼模拟试验

为了查明河水中氨污染对常见淡水鱼类危害程度,设计本项模拟试验。经测定：水中氨氮含量＞ ４ ｍ ｇ／Ｌ时,淡水鱼就会出现急性中毒现象。不同种类、大小的淡水鱼对氨氮的忍耐度不同,呈一定规律。中毒症状主要表现为鳃部呼吸、血液循环障碍及体表应激反应     

太湖中大银鱼_太湖新银鱼和寡齿新银鱼群体的遗传结构

利用ＲＡＰＤ技术对太湖中的大银鱼,太湖新银鱼,寡齿新银鱼的遗传结构进行了研究,共在太湖中的６个采样片采到大银鱼和太湖新银鱼样品,在两个采样片得到了寡齿新银鱼的样品。结果表明,太湖中不同水域的三种银鱼没有明显的遗传差异,三种银鱼中,大银鱼的遗传相似性指数显示最大,太湖新银鱼的次之,寡齿新银鱼的最小,说明大银鱼的遗传变异性最小,寡齿新银鱼的最大,太湖新银鱼的遗传变异性界两者之间。     

Antigenicity of cortical bone allografts in dogs and effect of ethylene oxide-sterilization.

The aims of the present study were to determine the antigenicity of cortical bone allografts and the effect of ethylene oxide-sterilization (EO-sterilization). Cortical bone allografts from one donor dog were implanted in a muscle pouch in four groups of four dogs each. The grafts were either fresh, EO-sterilized, demineralized or demineralized and EO-sterilized. The immune response against the grafts was determined by measuring the antibody response against surface antigens of donor cells and by the mixed lymphocyte reaction. Dogs receiving EO-sterilized grafts or bone matrix did not demonstrate an immune response. Only two of the four dogs with fresh cortical bone grafts showed a very weak immune response. This suggests a priming of the host by the fresh bone grafts. However, implanting skin grafts from the donor dog subdermally, in one dog of each of the groups, four months after implanting the bone grafts did not induce a secondary immune response. Macroscopic and histologic examination of the bone grafts five months after their implantation consistently revealed graft resorption (activity of osteoclasts) and vascularization of the fresh bone grafts, but not of EO-sterilized fresh grafts. For most EO-sterilized grafts, a strong inflammatory reaction was present in the tissues surrounding the graft and this was not apparent around the non-sterilized grafts. The absence of resorption and the presence of the inflammation seemed to be unwanted effects of the EO-sterilization. The EO-sterilisation did not affect osteoinduction since osteocytes were observed in the EO-sterilized demineralized grafts. Results indicate that cortical bone allografts used in the present study are very weak antigens and that the EO-sterilization procedure used has no effect on osteoinduction, but decreases bone resorption.