獭兔消化道pH及主要消化酶变化规律研究

试验选用15日龄、30日龄、60日龄、90日龄和成年獭兔各15只,对獭兔不同肠段(十二指肠、空肠和回肠、盲肠)pH、淀粉酶、胰蛋白酶、糜蛋白酶、脂肪酶和乳糖酶活性进行测定.结果表明:肠段不同,pH和酶活性不同.15日龄后獭兔各肠段pH变化不大,相同日龄pH:回肠>空肠>十二指肠.随着日龄的增加,淀粉酶、胰蛋白酶、糜蛋白酶和脂肪酶活性增加,乳糖酶的活性逐渐降低;相同日龄淀粉酶、胰蛋白酶、糜蛋白酶活性:空肠>回肠>十二指肠,乳糖酶活性:空肠>十二指肠>回肠.盲肠pH、淀粉酶和乳糖酶活性低于小肠,纤维素酶在60日龄后迅速增加;盲肠各消化酶活性90日龄后基本稳定.     

美国法律法规制定程序

在美国,国会通过的是法律授权,由总统签署后变成法律,联邦政府部门根据法律给予的授权制定实施法律的法规、规章。联邦政府部门制定法规时,要遵守《行政程序法》(Administra-tive Procedure Act,APA)规定的要求,还要考虑立法对小企业的影响(管理灵活性法,The Regu-latory Flexibility Act),对环境的影响(国家环境政策法,The National Environmental Policy Act),对法规中包含的任何信息收集的必要条件的影响(减少文书工作法,The Paperwork Reduction Act)等。APA规定了制定法规、规章的要求,包括联邦机构制定、修改或废除某项法规…     

罗非鱼源无乳链球菌S-核糖基高半胱氨酸酶基因（luxS）的克隆及其推导蛋白的三维结构预测

利用PCR技术对罗非鱼源无乳链球菌(Streptococcus agalactiae)S-核糖基高半胱氨酸酶（luxS）基因全长DNA进行了扩增、克隆和序列测定,采用ExPAsy软件包预测了推导蛋白的特性,利用Swiss-Model服务器建立了luxS 的三维结构,利用Swiss-PDBviewer软件进行了蛋白质三维结构的分析。预测结果显示,罗非鱼源无乳链球菌luxS推导蛋白包括保守的酶活性中心和锌结合位点,具有影响生物被膜形成、毒力因子调控等特性功能;经拉氏构象图（Ramachandran plot）分析,所构建的luxS的空间结构合理。     

鲢抗菌肽Hepcidin的基因克隆和表达及抑菌活性分析

利用同源克隆的方法从鲢（Hypophthalmichthys molitrix）的肝脏中克隆出抗菌肽Hepcidin cDNA（GenBank登入号KF312213）后,通过pET32a（+）构建含抗菌肽Hepcidin的重组质粒的pET-Hep/Rosetta菌株,在37 ℃、28 ℃和16 ℃下分别用0.5 mmolL-1和1.0 mmolL-1 IPTG诱导表达,产物用Ni SepharoseTM亲和层析柱纯化并进行体外抑菌试验。鲢Hepcidin cDNA总长度755 bp,ORF为282 bp,5'UTR为108 bp,3'UTR为365 bp,编码93氨基酸,信号肽24个氨基酸,前域42个氨基酸和成熟肽27个氨基酸。pET-Hep/Rosetta在28 ℃和16 ℃主要是可溶性表达,37 ℃主要是包涵体表达。纯化的产物经15% SDS-PAGE电泳验证为目的产物。目的产物、pET32/Rosetta产物以及氟苯尼考的体外抑菌试验表明,目的表达产物对无乳链球菌（Streptococcus agalactiae）、金黄色葡萄球菌（Staphylococcus aureus）、嗜水气单胞菌（Aeromonas hydrophila)等具有很好的抑菌效果。     

Papular dermatitis induced in guinea pigs by the biting midge Culicoides sonorensis (Diptera: Ceratopogonidae).

Histological, ultrastructural, and virological examinations were performed on abdominal skin from guinea pigs after a blood meal by colony-bred biting midges, Culicoides sonorensis. Small, superficial, cutaneous, crateriform ulcers with necrosis of superficial dermis developed at feeding sites and healed within 24-48 hours. Animals developed nonpruritic erythematous papules 5 days after feeding that persisted until the study ended at 12 days after feeding. Papules corresponded histologically to foci of epidermal hyperplasia and superficial interstitial dermatitis with intraepidermal micropustules and scattered intraepidermal polykaryons. The principal ultrastructural changes were spongiosis in germinal epithelium and neutrophilic-histiocytic exocytosis. No viral agents or broken mouthparts were identified in lesions. The dermatitis may represent a host reaction to persisting insect salivary secretion and should be considered as an additional consequence of blood feeding in future studies involving biting midges.     

Sex Ratio and Potential Fecundity of Atlantic Salmon (Salmo salar L.) Caught by Anglers on the Elorn River (Northern Brittany, France) during 1979 and 1980

Analysis of the sex ratio of angling Atlantic salmon catches from March to mid-June on the Elorn river in 1979 and 1980 showed a majority of females among the spring salmon population. Comparison between serodiagnostic technique and visual observations of gonads indicated that the former method provided a very low error margin for sex ratio determination on all females in the early stages of maturation and entering rivers. Study of sexual characteristics of spring salmon bearing copepod parasites or not indicated that fish entering freshwater would initiate a new stage of the ovogenesis process characterized by a failure of about 30% of the oocytes and a correlation between fecundity and size that did not exist at the time of the entry into freshwater.     

Could a diet enriched with n‐3 highly unsaturated fatty acids be considered a promising way to enhance the immune defences and the resistance of Penaeid prawns to environmental stress?

The prawn Penaeus stylirostris (Stimpson), when fed for 28 days with n‐3 highly unsaturated fatty acid (HUFA)‐enriched feed pellets, demonstrated an enhanced resistance to variations in environmental parameters (a decrease in temperature and salinity over a 4‐day period from 28 °C to 17 °C and from 35‰ to 10‰ respectively) and an improvement in their immune defence potential, i.e. increased agglutination titre of plasma and increased respiratory burst of haemocytes.     

工程施工中三大要素的监管

通过对某公司二个工程项目的现场施工监管 ,阐明了作为工程施工的三大要素(质量、投资、进度 )的监管及控制以及它们相互之间的关系