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1.
附红细胞体病是由立克次氏体引起的一种散在的热性、溶血性入畜共患传染病,病猪以急性黄疸性贫血和发热为特征。弓形体病是由刚地弓形虫在多种动物和入的有核细胞内寄生引起的一种入畜共患的原虫病。本文通过对某猪场发生猪附红细胞体与弓形体混合感染的诊治,从发病情况、临床症状、剖检变化、实验室诊断、治疗等方面对该病进行了阐述。  相似文献   
2.
Porcine epidemic diarrhea virus (PEDV) is the causative agent of neonatal diarrhea in piglets, which causes high mortality rates. In this study, the immunoprophylactic effects of chicken egg yolk immunoglobulin (Ig Y) against PEDV were investigated in neonatal pigs. Ig Y was found to reduce the mortality in piglets after challenge exposures. The field application of Ig Y also revealed significant differences in survival rates of piglets given Ig Y, as compared with placebo or control. The results in this study indicated that Ig Y against PEDV could be an alternative way of supplementing prophylactic measures like colostral antibodies from sows.  相似文献   
3.
This study was performed to evaluate the effect of beta-tricalcium phosphate and poly L-lactide-co-glycolide-co-epsilon-caprolactone (TCP/PLGC) membrane in the repair of partial bone defects in canine proximal humerus. Three adult mixed-breed dogs were used during the experimental period. The length of the defect was quarter of the full length of humerus, and width of the defect was quarter of middle diameter of the lateral aspect of humerus. The humeri of each dog were divided into treatment (TCP/PLGC) and control groups. The defect was covered with TCP/PLGC membrane in treatment group. To evaluate regeneration of the bone, computerized tomography (CT) and histopathologic examination were performed. The radiopaque lines were appeared at the original defect sites in TCP/PLGC group but below the original site in control at 4th week. Radiopacity and thickness of the defect sites, and radiopaque lines were more increased at 8th week than those of 4th week. Histopathologic findings revealed fibrous connective tissue migration into the defect and the migration inhibited the structure of new cortex to be placed in the original level in control whereas new cortex growth was found in the level of original line in TCP/PLGC group. However, the new cortical bone in the TCP/PLGC group was thinner and less organized than the adjacent intact cortex, and the amount of new cancellous bones were also scanty. The result suggested that TCP/PLGC membrane is a good guided bone regeneration material to restore the original morphology of humerus in partial defect.  相似文献   
4.
Thirty-four dogs with no deep pain perception due to acute thoracolumbar intervertebral disc disease underwent decompression surgery within 1 week of diagnosis. All dogs underwent hemilaminectomy. Adipose derived mesenchymal stem cells (AD-MSCs) were transplanted into the injured spinal cord parenchyma for the AD-MSCs transplant dogs. Long-term outcome was evaluated at the end of the follow-up period (> 6 months). AD-MSCs combination treatment showed better recovery outcomes compared to decompression surgery alone. These results indicate that this stem cell therapy is a potential therapeutic strategy to overcome the limitations of treatment for spinal cord injury in clinical medicine.  相似文献   
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Summary None of the tested cultivars of lettuce was found resistant to Stemphylium leaf spot, a common disease in Israel. Within a Lactuca saligna population collected in wild lettuce in Israel, resistance was traced. Interspecific crosses of L. saligna x L. sativa were made and the mode of inheritance of resistance to this disease was studied. Resistance is apparently controlled by two genes: one dominant (Sm1) and one recessive (sm2).Contribution No. 1176-E 1984 series, from the ARO.  相似文献   
7.
D2型细胞质与有些普通小麦材料的细胞核互作,可产生特异核质互作不育现象,其中有的表现为长光照敏感型雄性不育。文章研究了具有D2型细胞质的光敏不育系Ae.crassa—Norin26、核质杂种NC2134及克引11、克引12在黑龙江省克山地区自然条件下的育性表现,并以NC2134为细胞质供体,与20个小麦品种(系)杂交,获得一些核质代换系材料,对其育性及主要性状进行观察研究。结果表明:(1)在自然条件下,播种期对育性有影响,随着播种期推迟,Ae.crassa—Norin26不育度增加,1 999年4月22日播种达到全不育,Norin26则在所设播种条件下表现正常可育;(2)NC2134表现可育,这与其可能携带雄性不育的恢复基因有关,克引11、克引12在正常播种情况下表现高度不育甚至全不育;(3)不育系的不育性表现为不同程度的雄蕊心皮化;(4)不同普通小麦材料其核质杂种育性表现不同,有些材料其核质代换低世代分离出一定比例的高不育、半不育及可育株,通过进一步的核置换,可转育成相应的D2型细胞质不育系。  相似文献   
8.
Angle-resolved photoemission experiments reveal evidence of an energy gap in the normal state excitation spectrum of the cuprate superconductor Bi2Sr2CaCu2O8+delta. This gap exists only in underdoped samples and closes around the doping level at which the superconducting transition temperature Tc is a maximum. The momentum dependence and magnitude of the gap closely resemble those of the dx2-y2 gap observed in the superconducting state. This observation is consistent with results from several other experimental techniques, which also indicate the presence of a gap in the normal state. Some possible theoretical explanations for this effect are reviewed.  相似文献   
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10.
Post‐weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS) are two recently described conditions of pigs at the late nursery and fattening stages. The aim of this short communication was to describe the first reported occurrence of these conditions and of porcine circovirus type 2 (PCV2) infection in Greece. The clinical signs, gross post‐mortem changes and histopathological changes observed in affected pigs, were similar to those previously described for both PDNS and PMWS. As in previous reports, the lesions were associated with PCV2 infection, which was demonstrated by immunohistochemical and in situ hybridization methods.  相似文献   
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