一例梅花鹿炭疽的诊断体会

炭疽是一种急性、烈性的人畜共患病，１９９０年以来曾先后在我市的朱王堡、双湾等乡镇暴发和零星散发。发病畜主要是牛、羊，先后有十多人感染发病，给人民的健康造成了巨大的影响。梅花鹿感染炭疽的病例在我市尚属首次。１病情介绍１９９６年８月１日早晨８时，我市辖区内一养殖场饲养的一头２月龄的梅花仔鹿突然发病，表现为全身颤栗，口吐白沫，站立不稳，呼吸急迫，心跳亢进，体温超出４３℃（体温表被撑破），８时５０分左右全身痉挛死亡。由于该席曾于３日龄时患过大肠杆菌病，故驻场兽医对尸体进行了剖检。２剖检情况　　口腔含有大…     

Assessment of the effects of age and joint disease on hydroxyproline and glycosaminoglycan concentrations in synovial fluid from the metacarpophalangeal joint of horses

OBJECTIVE: To assess the effects of age and joint disease on hydroxyproline and glycosaminoglycan (GAG) concentrations in synovial fluid from the metacarpophalangeal joint of horses and evaluate the association of those concentrations with severity of osteoarthritis and general matrix metalloproteinase (MMP) activity. SAMPLE POPULATION: Synovial fluid was collected from the metacarpophalangeal joints of foals at birth (n = 10), 5-month-old foals (10), 11-month-old foals (5), and adult horses (73). PROCEDURE: Hydroxyproline and GAG concentrations were determined in synovial fluid samples. The severity of osteoarthritis in adult joints was quantified by use of a cartilage degeneration index (CDI) and assessment of general MMP-activity via a fluorogenic assay. RESULTS: Hydroxyproline and GAG concentrations in synovial fluid were highest in neonates and decreased with age. Concentrations reached a plateau in adults by 4 years and remained constant in healthy joints. In synovial fluid from osteoarthritic joints, hydroxyproline and GAG concentrations were not increased, compared with unaffected joints, but hydroxyproline were significantly correlated with the CDI and general MMP activity. There was no significant correlation between GAG concentration and CDI value or MMP activity. CONCLUSIONS AND CLINICAL RELEVANCE: Changes in hydroxyproline concentration in synovial fluid appeared to indicate damage to collagen of the articular cartilage. In joints with osteoarthritis, the lack of high GAG concentration in synovial fluid and the absence of a significant correlation between GAG concentration and CDI values or MMP activity may severely limit the usefulness of this marker for monitoring equine joint disease.     

INVESTIGATION OF SHEEP DIPS

Groups of 30 sheep of four breeds (Merino, Dorset Horn, Romney Marsh and Border Leicester), that had been maintained under the same environmental and nutritional conditions were used in showering experiments with a diazinon emulsion. The fleeces of all breeds stripped (or depleted) diazinon from the dipping fluid. Diazinon was not deposited evenly down the length of the wool staple. On the Merino fleece, more diazinon was deposited on the outer section and less on the inner section near the skin. On the other breeds, more diazinon was found in the inner and less on the outer sections. Differences in the magnitude and location of the diazinon deposits are discussed, with the aid of supplementary in vitro dipping experiments, in relation to the compactness of the fleece and the amounts and distribution of wax, suint and dirt found there.     

系统耦合与荒漠─绿洲草地农业系统─—以祁连山一临泽剖面为例

生态系统内部自由能的积累，使系统失去平衡并趋于同其它生态系统结合，自由能驱使两个或两个以上的生态系统或亚生态系统，通过会聚，超循环和耦合而联合，从而形成具有特殊结构一功能的更高一级的新系统。系统耦合可以多途径解放生态系统中的自由能而增加农业生态系统的生产力，亦即从催化潜势，位差潜势，多稳定潜势及管理潜势中取得能输出。上述过程可作用于农业系统中的四个子系统，这四个子系统各有自己的产品：前植物生产，植物生产，动物生产，外生物生产，从而大幅度提高其生产力。在荒漠─绿洲草地农业生态系统中，本文分别计量了各个子系统的能流单位及其流程，证明它的子系统也可以成功的发生系统耦合，其中绿洲子系统应居关键地位。     

家蚕原种人工饲料适应性品系的选拔

研究了家蚕中、日系原种与杂交种对人工饲料适应性的差异；经累代定向选择，建立了苏５、青松人工饲料适应性品系，该品系对人工饲料适应性比非选拔系有明显提高，配以优良的原种饲料，进行原种稚蚕人工饲料育，综合成绩基本达到桑叶育水平。     

盐分对碱茅种子发芽影响的机制

耐碱茅种子在盐（NaCl与Na2SO4）及干旱（PEG－6000模拟）胁迫下发芽及其机制的比较研究表明，种子发芽率随溶液渗透势的降低而下降，在等渗条件下三种溶液中的发芽率次序为Na2SO4＞NaCl＞PEG。NaCl与Na2SO4主要通过影响种子吸水量及对膜的毒性影响发芽，根据相关及通径分析结果，其机制为：（1）溶液渗透势及Na+浓度决定的种子吸水对发芽的直接正效应（通径系数0．73）；（2）溶液Na+浓度引起的膜毒性对发芽的直接负效应（－0．51）；（3）种子从溶液中吸收Na使种子吸水增加对发芽的间接正效应（0．30）及使膜毒性增大对发芽的间接负效应（－0．24）。     

布鲁氏菌M5-90△WboA基因缺失株的构建及免疫效果的初步评价

为获得毒力较弱并能区分自然感染和疫苗免疫的布鲁氏菌候选疫苗株,本研究用PCR方法扩增WboA基因的上下游同源臂序列,构建重组质粒pGEM-7zf-△WboA-Sac,电转化布鲁氏菌M5-90感受态细胞,筛选布鲁氏菌疫苗株M5-90的WboA基因缺失株,并对获得的M5-90△WboA遗传稳定性、毒力、免疫保护性、抗体水平等指标进行检测.实验结果表明M5-90△WboA株的毒力比M5-90株明显减弱,差异极显著(p＜0.01),体液免疫和细胞免疫结果表明M5-90△WboA株与亲本M5-90株相比差异不显著(p＜0.05),M5-90△WboA株和亲本株的保护率分别为10％和20％,表明M5-90△WboA株与M5-90株具有相似的保护性.凝集试验和western blot试验显示M5-90△WboA株免疫小鼠的血清反应结果为阴性.本研究构建的布鲁氏菌基因缺失株M5-90△WboA具有较好的遗传稳定性,毒力比亲本株更弱,免疫保护性与亲本株相当,并能以血清学检测方法区分野毒株感染和缺失疫苗株免疫的动物.