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91.
Insufficient agreement on scoring hip quality might be caused by differences in the assessability of a radiograph (exposure, contrast, positioning, and diagnostic quality). We studied the agreement in assessability of standard ventrodorsal hip-extended radiographs by experienced (nine) and inexperienced (21) observers, using the standard subjective method of quality control, currently applied in screening programs. The effect of assessability on the agreement of scoring hip quality [dysplastic vs. nondysplastic and the final Federation Cinologique International (FCI) score] was also investigated. There was a significant difference ( P <0.0001) in agreement on assessability between the experienced and inexperienced observers. In 68% of evaluations, experienced observers stated that the radiograph was assessable. Inexperienced observers evaluated the radiographs as being assessable in only 46.5% of evaluations. Increased interobserver agreement on assessability of a radiograph did not increase the overall interobserver agreement in the diagnosis of hip dysplasia, nor did it result in consistent scoring of the hip status from that radiograph, despite a significant ( P <0.05) increase in agreement of FCI scoring with an increasing agreement on assessability at a one to five ratio in the experienced group. The inconsistent evaluation of radiographic quality, as well as the inconsistent evaluation of the hip quality, caused differences in diagnosing hip dysplasia and FCI scoring in the same dog ranging from excellent hips to moderate hip dysplasia. Therefore, the credibility of the FCI screening method for canine hip dysplasia, using the standard hip-extended radiographic view, as currently applied in most European countries, is questionable.  相似文献   
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Experienced and inexperienced observers evaluated the assessability of 50 radiographs (25 dogs) and determined the hip status (dysplasia/nondysplasia and final scoring according Fédération Cynologique Internationale [FCI]‐criteria) individually. A radiographic technical quality assessment was performed in a separate reading session. Interobserver agreement in determining dysplasia/nondysplasia and FCI‐scoring did not significantly increase with the increasing quality of a radiograph, irrespective whether these observers are experienced or not. There was a significant agreement between the technical quality assessment and assessability (P<0.0005). Despite the effort to objectify radiographic quality and to present high‐quality radiographs to observers, interobserver agreement on dysplasia/nondysplasia and final scoring, remains low, even in the experienced group. Although increased radiographic quality narrows the range of scoring, the range remains unacceptably high.  相似文献   
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噬菌体用于柞蚕空胴病生物防治的研究   总被引:2,自引:0,他引:2  
应用柞蚕链球菌噬菌体对作蚕空胴病进行生物防冶的结果证明:用噬菌体卵面消毒具有明显的效果,而用钠一噬菌体其效果更为明显,对蚕卵的孵化率无明显影响。大面积生产鉴定证明:蚕茧的产量可增产4倍。方法简便、安全、有效,易于推广。  相似文献   
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VAN DER KAMP  B. J. 《Forestry》1969,42(2):185-201
The stages in the formation of Peridermium pini lesions aredescribed. The hyphae of the parasite were septate, uninucleate,and intercellular, with unbranched haustoria penetrating allphloem cells and xylem parenchyma cells. Lesion extension occurredby apical growth of the hyphae along the outer edge of the functionalphloem. The hyphae stretched unbroken across the active cambium.Active centripetal and longitudinal growth of the mycelium occurredin the resin ducts of the xylem, the hyphae commonly reachingthe pith. Spermogonia were produced in late summer and fall,aecia appeared in spring. In lesion xylem, tracheids were shorter,rays taller, more numerous and wider, but ray cell height remainedunchanged. Fusiform rays increased in number and size and verticalresin ducts increased in number. Changes in xylem tissues didnot become evident until two to four years after invasion ofthe cambium by the mycelium. Invasion of the secondary phloemresulted in an increase in number and size of the longitudinalphloem parenchmya cells, while changes in phloem rays were similarto those in xylem rays.  相似文献   
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