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91.
利用一种微生态保健品和3种抗菌素药物,即氟哌酸、氯霉素、庆大霉素在兽医临床上用于治疗仔猪黄白痢,断奶猪的应激性腹泻,肥猪及母猪的腹泻作了对比试验,结果表明:微生态保健品对仔猪黄痢的治愈率为93%,对仔猪白痢的治愈率为95%,对断奶仔猪的应激性腹泻治愈率为94%,对肥猪及母猪的腹泻治愈率为100%。与氟哌酸、庆大霉素的疗效比较,差异显著(P<0.05);与氯霉素比较差异极显著(P<0.01). 相似文献
92.
93.
将构建的pBST2~6工程菌质粒用限制性内切酶BamHI/BglⅡ酶切,经琼脂糖凝胶电泳和电洗脱,回收147bp的目的ST1基因。随之将该基因分别重组到能有效表达K99菌毛抗原和LacZ酶的pGK99之K99基因BglⅡ位点和pUC18的BamHI位点中。通过ST1基因探针菌落原位杂交、特定酶切分析及DNA序列分析,筛选并鉴定出了理想重组子,从而构建出了能分别表达ST1融合基因产物的工程菌株pSK219和pXST1。 相似文献
94.
犬瘟热的微生物学诊断研究 总被引:13,自引:1,他引:12
对临床诊断为犬瘟热的14例病犬,取其脑组织,运用细胞培养、合胞体检查、包涵体检查、免疫荧光试验、电镜观察等5种检测方法,就犬瘟热的微生物学诊断进行了系统的研究。结果表明,犬脑组织块与猫胚(FE)细胞或非洲绿猴肾(Vero)细胞共同培养,盲传的培养物出现不稳定的细胞病变,通过对不同代次的培养物检查包涵体,并作超薄切片或负染,电镜观察犬瘟热病毒(CDV)粒子,证实分离到CDV野毒。病犬脑组织切片经HE染色检查包涵体及用CDV荧光抗体直接法检测脑抹片及接种犬脑的细胞培养物,均获得一定的阳性结果。建立的改良离子捕获电镜法,用于检测犬脑匀浆和犬脑接种细胞培养物,与离子捕获电镜法、免疫电镜法及直接电镜法相比,效果更为理想。14例临床诊断为犬瘟热的病犬,综合运用上述微生物学手段检测,结果为12例阳性,2例疑似。 相似文献
95.
96.
根据鱼藤中异黄酮类化合物在紫外光210~245nm及290~305nm处具有吸收峰这一特性,提出了用紫外分光法测定鱼藤中异黄酮类总含量的方法.在300nm波长处,浓度低于6×2.618×10-3/mol·L-1时,测定了标准系列的吸光值,结果表明吸光值与浓度近乎直线相关,相关系数为0.9977;标准系列吸光值准确性高;加样回收率达99%以上;测定样品时,重现性好. 相似文献
97.
Soil pH declined from 5.9 to 5.0 in 8 years beneath plantations of Eucalyptus saligna (Sm.) in Hawaii. In stands of Albizia falcataria, (L.) Fosberg, the soil pH change was more dramatic, declining from 5.9 to 4.6. We measured several components of soil acidity beneath four mixtures of the two tree species to gain insight on the processes responsible for the decline in soil pH. These components were studied using an empirical method of comparing acid quantity, degree of neutralization (depletion of base cations), and acid strength. The decline in soil pH differed between species as a result of differences in the degree of neutralization of the soil exchange complex; the larger decrease in soil pH under Albizia was produced by greater acidification of the exchange complex. Empirical titration curves suggested that differences in acid strength moderated the divergence in soil pH beneath the species. Had the acids accumulating in the soil under Albizia been as strong as those in the Eucalyptus soil, the difference in soil pH would have been greater. Though the two species had contrasting effects on soil pH, the differences in degree of neutralization, responsible for the pH decline, were small compared with differences in the amount of cations stored in tree biomass. Continued supply of nutrient cations (from weathering or fertilization) will ultimately control both the extent of soil pH decline and the level of productivity sustained by the forest. 相似文献
98.
Monoclonal antibodies to bovine viral diarrhea virus: cross-reactivities to field isolates and hog cholera virus strains. 总被引:2,自引:1,他引:1
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Monoclonal antibodies to bovine viral diarrhea virus (BVDV) were examined for binding with a large number of North American BVDV isolates and eight strains of the serologically related pestivirus, hog cholera virus (HCV). No single BVDV monoclonal antibody reacted with all BVDV isolates. The most cross-reactive monoclonal antibody was an anti-p80/p125 antibody which showed a positive reaction with 173 of 180 (96%) North American isolates. From a fewer number of isolates tested, one anti-gp53 monoclonal antibody also showed a high cross-reactivity (94%). All BVDV isolates showed a positive reaction with at least one of the seven monoclonal antibodies in the panel. Thus, the results indicated that a pool of these monoclonal antibodies may be used in place of polyclonal antisera for the detection of BVDV contamination of cell lines or for virus isolation. For HCV, all three anti-p80/p125 monoclonal antibodies reacted positively with all eight virus strains. In contrast, none of the anti-gp53 monoclonal antibodies were reactive to HCV strains. Thus, the anti-gp53 monoclonal antibodies may be useful for distinguishing between usually innocuous BVDV infections and the highly significant HCV infections in swine for foreign animal disease surveillance. 相似文献
99.
Comparative effects of mu and kappa opiate agonists on the cecocolic motility in the pony.
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The electrical and mechanical activity of the large intestine and its response to administration of opiate mu and kappa agonists were assessed from electrodes and inductograph coils chronically implanted on the cecocolic segment in six ponies given a diet of hay and concentrates. Before the drugs were given, migrating complexes propagating from the cecum into the colon occurred at the rate of 1.5 to 16/hour. During this propulsive activity, the cecocolic sphincter opened and closed allowing the outflow of cecal contents and preventing the backflow of colic contents. Each pony was used as its own control and was given fentanyl (0.01 and 0.05 mg/kg of body weight, IV) and U50488H (0.1 and 0.5 mg/kg, IV) at weekly intervals. The mu agonist fentanyl elicited a marked phase of inhibition of the propulsive activity and a closure of the cecocolic sphincter that lasted one to two hours depending on the dose. The kappa agonist U50488H induced an inhibition of the short spiking activity, i.e. of the resting muscle tone. It did not disturb the occurrence of migrating complexes nor that of the openings of the cecocolic sphincter. These kappa compounds may be drugs of choice to alleviate visceral pain in colic stases without inducing delay of transit unlike mu compounds. 相似文献
100.
地膜覆盖对棉枯萎病发生的影响 总被引:1,自引:0,他引:1
地膜覆盖显著降低了棉花枯萎病的发病率与病情指数,极显著地提高了棉花的产量。 相似文献