绢丝昆虫茧丝蛋白酶抑制剂含量的比较分析

以 6种绢丝昆虫的茧壳为材料 ,对茧丝蛋白酶抑制剂的含量及热稳定性进行了研究。结果表明 :家蚕品种间茧丝蛋白酶抑制剂的含量差异极显著 ,外层丝中含量较多 ,F1代的含量呈双亲中间型 ,偏向于含量较多的亲本 ,雌雄间含量无显著差异 ;家蚕茧丝蛋白酶抑制剂对热稳定性较强 ;天蚕绿茧、野蚕的茧丝中有少量的蛋白酶抑制剂存在 ,蓖麻蚕的茧丝中有微量蛋白酶抑制剂存在 ,天蚕黄茧、柞蚕茧、樗蚕茧的茧丝中基本无蛋白酶抑制剂存在。     

The failure of selenium supplementation to prevent copper-induced liver damage in Fischer 344 rats.

This study evaluates the ability of selenium (Se) supplementation to prevent experimental copper (Cu)-induced hepatocellular damage. Weanling male Fischer 344 rats were randomly assigned to groups of 15, 3 groups (A,B,C) were fed Cu-loaded diets (containing 2000 microg/g copper, added as CuSO4) and different levels of Se (added as Na2SeO3 x 5H2O) as follows: A) Cu-loaded/Se adequate diet (0.4 microg/g Se, fed basis); B) Cu-loaded/Se-supplemented diet (2 microg/g Se); and C) Cu-loaded/Se-deficient diet (< 0.2 microg/g). Three additional groups (D,E,F) were fed diets containing adequate levels of Cu (14 microg/g Cu, fed basis) and different levels of Se as follows: D) Cu-adequate/Se-adequate diet; E) Cu-adequate/Se-supplemented diet (2 microg/g Se); and F) Cu-adequate/Se-deficient (< 0.2 microg/g) diet. After 4, 8, and 12 weeks on the experimental diets, liver samples were processed for histology, histochemistry, metal analysis, glutathione peroxidase (GSH-Px) measurement, and quantification of malondialdehyde (MDA). Morphologic changes characteristic of Cu-associated hepatitis, without an increase in hepatic MDA levels, were seen in all Cu-loaded rats in each sampling. Similar changes occurred in rats fed Se-adequate, Se-supplemented and Se-deficient diets. This study demonstrates that Fischer 344 rats fed 2000 microg/g Cu develop morphologic changes due to Cu toxicity without evidence of lipid peroxidation. Furthermore, Se supplementation does not result in protection against Cu-induced liver injury.     

GIS在生态土地分类中的作用

This paper depicted the physiographic landscape features and natural vegetation situation of study area (the eastern Jilin Province), and expatiates the definition, basic characters and its development of Ecological Land Classification (ELC). Based on the combination of relief map, satellite photography for study area and vegetation inventory data of 480 sample sites, a 5-class and a 15-class ecological land type map was concluded according to 4 important factors including slope, aspect, vegetation and elevation. Ecological Classification System (ECS) is a method to identify, characterize, and map ecosystems. The Ecological Land Type (ELT) was examined and applied initially in eastern Jilin Province. Foundation item: This paper was supported by Chinese Academy of Sciences “100 people” project and the Open Research Station of Changbai Mountain Forest Ecosystem. Biography: XIAO Bao-ying (1974-), female, postgraduate in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. China Responsible editor: Zhu Hong     

关于做好党风廉政教育工作的几点思考

党风廉政教育在党风廉政建设和反腐败斗争中具有重要的作用。做好新形势下的党风廉政建设工作，就必须开展行之有效的党风廉政教育活动，并做到认识到位、意识突出、机制创新、措施完备、内容丰富和参与积极。     

哈密市奶牛结核病、布鲁氏杆菌病感染情况的调查

结核病与布鲁氏杆菌病都是对人体健康有严重危害的人畜共患传染病。据卫生部门统计，我国现有结核病病人近６００万人，每年因结核病死亡的约２５万人，是单一病菌引起死亡最多的传染病。仅１９９８年第三季度新疆结核病发现人数为 ４ ７９４人，由此可见，此病对人类健康有较大的威胁。而布鲁氏杆菌病同样是人畜共患的全身性传染病，且结核病和布鲁氏杆菌病的传播途径相同，由于人类的结核和畜禽结核有较强的相互交叉感染性，结合我地区实施“放心肉、放心奶”跨世纪“牧业工程”，我们于２０００年春、秋两季对哈密市郊区的５００余头奶牛…     

甲鱼健康快速养殖的几点思考

甲鱼健康养殖就是要求生产者尽量为甲鱼创造良好的生态条件，加强科学饲养管理，使其体质强壮，生长代谢机能及免疫系统正常，不用药或少用药，严禁使用对人体有损害而在鳖体内有储积残留的药物，如孔雀石绿、硝酸亚汞、激素等药物，减少甲鱼发病机率，从而使养成的商品鳖真正成为消费者心目中的“绿色食品”。 快速养殖则是指在健康养殖的前提下，缩短养殖周期，加快资金周转，以其降低成本，提高经济效益。 健康快速养鳖技术的要点： １．种苗 ①选择本地生产的品质优良的杂交种苗，避免近亲繁殖。 近年，亲鳖种质退化、近亲繁殖已成为鳖…     

用铬变素2R法对家蚕微孢子虫孢子染色的研究

采用铬变素 2R法 (Chromotrope 2R)染色家蚕微孢子虫 (Nosemabombycis,N .b)孢子和绿僵 (Nomuraearile yi)孢子、曲霉 (Aspergillusflavus)孢子、花粉粒 (Pollengranule)等与N .b孢子形状相似物 ,结果表明 :Chromotrope 2R法特异性地将N .b孢子染成粉红色 ,绿僵孢子、曲霉孢子、花粉粒未被染成红色 ,初步认为Chromotrope 2R法可应用于母蛾镜检的N .b鉴定 ,能明显提高N .b的检出率与准确性 ;染色N .b孢子的最佳时间与温度为 4 0min ,30℃。鉴于本染色法的条件、技术操作简便 ,染色特异性强 ,因而具有良好的应用前景     

再论新形势下的乡镇企业

乡镇企业如何走出目前的经营困境，如何确定自己的战略选择，不同的人会有不同的认识。笔者试图从经营理念和管理者收购这一“软”一“硬”两方面做一些探讨。     

Mycoplasma hyopneumoniae colonization of pigs sired by different boars

Differences in Mycoplasma hyopneumoniae colonization were evaluated in experimentally inoculated pigs sired by 3 different boars of the same genetic line. Forty-six pigs were used, including a treatment group and positive and negative control groups. The pigs were intratracheally inoculated with an M. hyopneumoniae suspension or with Friis media as a placebo. To evaluate differences in the magnitude of colonization during a 35-day period, nasal and tracheal swabs were collected weekly and tested by nested polymerase chain reaction (N-PCR). Temperature, weight and circulating antibodies were measured for 35 days. At 11 and 35 d postinoculation the pigs were necropsied and macroscopic and microscopic lesions were determined. A section of bronchus was tested by the indirect immunofluorescence test (IFAT), scanning electron microscopy (SEM) and N-PCR. The N-PCR results from the nasal and tracheal swabs showed that the pigs sired by one boar (B3) had a distinctive colonization pattern, different from that of the pigs from the other 2 boars and from the positive controls. SEM studies demonstrated that at 35 d postinoculation a higher proportion of B3 pigs had lower numbers of mycoplasmas attached to the cilia compared with B1 and B2 offspring. No significant differences were observed in temperature and weight gain among groups by ANOVA; however, with use of a 2 × 2 table, temperature differences were observed between pigs sired by boars B1 and B2 at 4 d postinoculation. No pigs seroconverted, showed gross or microscopic lesions, or had positive IFAT results. These results provide evidence of differences in patterns of colonization between pigs sired by different boars, suggesting a possible genetic effect.     

自锁封闭式启闭机闸门在灌区节水中的应用

为适应按库配水，按方收费的需要，达到节约用水的目的，研制了自锁封闭式启闭机闸门。该装置将闸门和启闭机融为一体，封闭于地下，易操作，节水。介绍了其工作原理、工程结构和施工方法。