鸡抗球虫药的体外筛选综述

抗鸡球虫药的筛选分为体内筛选和体外筛选。体外筛选具有简易、迅速、准确和经济的优点。本文在前人大量工作的基础上，总结了体外筛选的全过程，并分述了细胞培养筛选法和鸡胚培养筛选法。     

山羊孤雌胚胎的体外培养

系统地研究了培养液微滴的大小、培养液体系及血清浓度对山羊孤雌胚胎早期体外发育的影响。结果表明，培养液微滴以较大体积(200～500μL)的培养效果较好；在3种培养液中，添加10％的NGS对山羊孤雌胚胎的体外发育效果较好，囊胚率分别可达62．79％(81／129)、53．52％(38／71)、13．64％(12／88)；mCRlaa组囊胚发育率和囊胚细胞数显著低于SOFaa组和CRlaa组，SOFaa组优于CRlaa组，尽管SOFaa组和CRlaa组间无显著差异。在本试验条件下，以SOFaa培养液，山羊孤雌胚胎体外培养72h时加入10％的NGs，500μL微滴培养，其发育效果较好，囊胚率可达62．79％。     

猪肾脏中氯丙嗪和异丙嗪残留检测方法的建立

建立了猪肾脏中氯丙嗪和异丙嗪残留量检测的高效液相色谱法。猪肾脏中残留的氯丙嗪和异丙嗪,用乙腈提取,再依次用酸化乙腈和正己烷净化,氮气吹干,甲醇溶解后,用Waters高效液相色谱系统,HypersilC18柱,UV检测器,用V(乙腈)∶V(水)∶V(0.5mol·L-1乙酸铵)(50∶49∶1)为流动相,流速1.2mL/min,波长254nm测定,内标法定量。结果表明,氯丙嗪和异丙嗪在猪肾脏中的最低检测限均为10μg/kg,组织中添加量为10μg/kg时,氯丙嗪和异丙嗪的回收率分别为83%和84%,批间变异系数均小于20%。该方法样品处理简单,可同时检测氯丙嗪和异丙嗪在猪肾脏中的残留量。     

添加不同酵母培养物对瘤胃纤维分解菌群和纤维素酶活的影响

用3种酵母培养物(YC- 1、YC 2和YC- 3)分别饲喂4头带有永久性瘤胃瘘管的肉牛,研究培养物对瘤胃发酵、纤维分解酶活性和3种纤维分解菌数量的影响,结果表明:YC 2处理的乙酸、丙酸、丁酸和总 VFA浓度显著高于对照组(P<0 .05),YC 1和YC 3处理的乙酸/丙酸比例显著降低(P<0 .01);各处理均能显著提高瘤胃内羧甲基纤维素酶、水杨苷酶和木聚糖酶的活性(P<0 .01);各处理都显著提高黄化瘤胃球菌的相对比例(P<0 .01),16SrRNA特异性寡聚核苷酸探针杂交法分析测定结果表明 3 种纤维分解菌在瘤胃细菌中所占比例为 3. 80%±0 .2%。     

北京油鸡胚胎成纤维细胞系建立与生物学特性研究

采取组织块直接培养法，对北京油鸡胚胎组织进行原代和继代培养，成功地建立了成纤维细胞系。并对培养细胞进行了形态学、细胞生长动力学观察，以及核型和乳酸脱氢酶、苹果酸脱氢酶的同工酶分析。结果表明，该细胞系的群体倍增时间(PDT)为24h；细胞染色体中二倍体占主体，为76％～88％；乳酸脱氢酶、苹果酸脱氢酶同工酶电泳图谱与本室其它细胞系有明显差别；细菌、真菌、病毒、支原体检测呈阴性。该细胞系的建立，使北京油鸡这一国家重要种质资源在细胞水平上保存下来，也为基因组文库和体细胞克隆等研究提供了理想的生物材料。     

Effects of five cryoprotectants on proliferation and differentiation‐related gene expression of frozen‐thawed bovine calf testicular tissue

The cryopreservation of testicular tissue is a potential method for preserving male fertility. However, the effect of cryopreservation on bovine calf testicular tissue is scarce. This study investigated the effect of different cryoprotectants on bovine calf testicular tissue at the molecular level. Testicular tissue from ten immature bovine calves (6 months) was collected after slaughter and cryopreserved in an extender containing different concentrations of the following five cryopreservation solutions (CP): bovine serum albumin (BSA) with 5% dimethyl sulfoxide (DMSO), trehalose with 5% DMSO, DMSO and glycerol and ethylene glycol (EG). After 7‐day cryopreservation, the expression levels of three spermatogonial stem cell (SSC)‐related genes, octamer‐4 (OCT4), KIT ligand (MGF/SCF) and kit oncogene (C‐KIT), were investigated by quantitative PCR (qPCR). The cell viability was highest for the tissues preserved with 30 mg/ml BSA (77.82% ± 1.22) and 40 mg/ml trehalose (74.23% ± 1.16) compared with other groups (p < 0.05), and the level of expression of the three genes was highest with 30 mg/ml BSA (p < 0.05). Compared with other CPs, the 30 mg/ml BSA and 40 mg/ml trehalose have the better cryopreserve protection. The 30 mg/ml BSA is the most viable media for the cryopreservation of testicular tissue from cattle.     

论我国行政文化的传统特征与现代重构

以“官本位”、“人治”、集权和封闭性与排他性为特征的我国传统行政文化正受到严峻挑战。服务行政、法治化行政、参与式行政和整合行政将是我国行政文化现代重构的价值选择，从而更好推动我国社会经济的发展。     

Identification of Suspected Stem/progenitor Cells in Bovine Mammary Epithelial Cells Culture System

To develop the potential function of dairy cow mammary stem cells (DCMECs) in regulation of lactation,we identify putative DCMECs which were BrdU label retaining epithelial cells,at the same time,analysis the location of two new mammary stem cells molecular marks FNDC3B and PROCR to verify the feasibility of them to indicate DCMECs.The mRNA levels of prolactin,growth hormone,insulin-like growth factor-1 and their receptors were detected along with cell passage by Real-time quantitative PCR.The results showed that the proportion of BrdU label-retaining epithelial cells was nearly 0.4% after 25 d continuous culture (passaged 4 times) and few cells were positive for FNDC3B or PROCR.Moreover,we observed the BrdU labelled epithelial cells by asymmetric division.The mRNA levels of prolactin,growth hormone,insulin-like growth factor-Ⅰ and their receptors in primary and passage cells were extremely significant difference(P<0.01).DCMECs would rapidly lose some physiological characteristics and the ability of milk synthesis when not under the condition of induction of lactation differentiation,but a certain percentage of mammary stem/progenitor cells will be retained,whose potential effects on the regulation of lactation and mammary acinar remodeling were worthy of attention.     

椰子组培研究四十年

组织培养对于椰子快速繁殖以及全球椰子产业发展具有重要意义。本文就40年来国内外在椰子组培快繁技术,包括椰子组培技术的重要性,不同外植体如胚芽、花序、子房等在组织培养中的应用与优劣,不同培养基和培育环境对组培效果的影响等要素,进行了详细的总结和讨论。同时总结了椰子组培快繁技术的进展,分析了目前限制椰子组培快繁技术发展的因素,提出了应对策略与具体建议。本文对椰子快繁技术及椰子种质资源保存具有参考价值。     

Differential Cl−/Salt Tolerance and NaCl‐Induced Alternations of Tissue and Cellular Ion Fluxes in Glycine max,Glycine soja and their Hybrid Seedlings

The salt‐sensitive Glycine max N23674 cultivar, the salt‐born Glycine soja BB52 population, and their hybrid 4076 strain (F₅) selected for salt tolerance generation by generation were used as the experimental materials in this study. First, the effects of NaCl stress on seed germination, tissue damage, and time‐course ionic absorption and transportation were compared. When qualitatively compared with seed germination appearance in culture dishes, and tissue damages on roots or leaves of seedlings, or quantitatively compared with the relative salt injury rate, the inhibition on N23674 was all the most remarkable. After the exposure of 140 mm NaCl for 1 h, 4 h, 8 h, 12 h, 2 days and 4 days, the content of Cl^? gradually increased in the roots and leaves of seedlings of BB52, 4076 and 23674. Interestingly, the extents of the Cl^? rise in roots of the three experimental soybean materials were BB52 > 4076 > N23674, whereas those in leaves were just on the contrary. Secondly, by using the scanning ion‐selective electrode technique (SIET), fluxes of Na⁺ and Cl^? in roots and protoplasts isolated from roots and leaves were also investigated among the three experimental soybean materials. After 140 mm NaCl stress for 2, 4 and 6 days, and when compared with N23674, slighter net Cl^? influxes were observed in root tissue and protoplasts of roots and leaves of BB52 and 4076 seedlings, especially at the cellular protoplast level. The results indicate that with regard to the ionic effect of NaCl stress, Cl^? was the main determinant salt ion for salt tolerance in G. soja, G. max and their hybrid, and the difference in their Cl^?/salt tolerance is mainly attributed to the capacity of Cl^? restriction to the plant above‐ground parts such as leaves.