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991.
A case of facial duplication with its surgical correction in childhood and the consequences on facial growth is reported. It is a unique case in the duration of observation. The following structures were fully duplicated: the nose, the premaxilla, the cribriform plate, the crista galli. In addition there was an enormous facial cleft including lip, alveolus and palate. Additionally there were two rudimentary eye sockets, eyes, and two supplementary eyebrows. The monstrous hypertelorism with the facial duplication was corrected at the age of ten. The surgical procedure is described and the postoperative complications are discussed. Gross lack of growth of the middle third of the facial skeleton was observed. This was probably the consequence of the initial corrective surgery. Overgrowth of the mandible created a gorilla-like appearance by the end of the growth period. This was corrected in one operation by advancement of the middle third in three sections and repositioning of the mandible as a whole together with the mandibular anterior alveolar segment. Finally all parts of the lower half of the nose had to be enlarged, both soft tissues as well as the cartilaginous framework. A pharyngoplasty in addition to the correction of the intermaxillary abnormalities did much to improve the speech quality of the patient. A large secondary cranial defect was successfully reconstructed with the use of 14 halved ribs. In spite of the removal of four ribs from one side and three ribs from the other, there were no postoperative respiratory problems. Spontaneous rib regeneration was found where ribs had been removed one year earlier.  相似文献   
992.
The purposes of this study were to determine differences in interpretation of radiographic findings of full-mouth and panoramic surveys by junior and senior dental students and differences in their interpretive skills. The parameters of interest were caries, incipiencies, lamina dura interruptions, periodontal membrane changes, and periapical bone changes. The questions to be answered regarding the differences between the full-mouth and panoramic surveys were: (1) In which type of radiograph were the most lesions found? (2) In which type of radiograph are the most "non-existing" lesions found? (3) In which type of radiograph are the most lesions undetected? (4) Does the junior or senior dental student demonstrate the most accuracy in his interpretation?  相似文献   
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994.
Horseradish peroxidase was injected into the tail veins of adult mice. Enamel organs were excised from mice killed at predetermined intervals, fixed in formaldehyde-glutaraldehyde, incubated in diaminobenzidine medium, post-fixed in OsO4, and processed for electron microscopy. Within 5 min of peroxidase administration, the reaction product was seen extracellularly between papillary cells and between reduced ameloblasts, but not beyond the apical terminal bar apparatus. Only papillary cells took up the peroxidase intracellularly via bristle-coated vesicles. Within the papillary cells, peroxidase was also seen in tubular structures, and at 30–60 min intervals in numerous multivesicular bodies.The results demonstrate that (1) the basal terminal bar apparatus of reduced ameloblasts is permeable to peroxidase, whereas the apical is not, (2) papillary cells function in the absorption of protein from the capillaries, and (3) bristle-coated vesicles and tubular structures serve to transport absorbed protein to multivesicular bodies within papillary cells.  相似文献   
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996.
The binding of chlorhexidine to proteins in vitro has been shown to involve albumin in both serum and saliva. The binding, which is pH- and concentration-dependent, occurs both to proteins remaining in solution and to proteins precipitated during the reaction. Both reactions are reversible, although that to precipitated protein apparently involves a stronger binding. If the latter can be correlated to the in vivo situation, it is suggested as a possible explanation of the extended retention of chlorhexidine in the mouth despite the rather rapid turnover of saliva.  相似文献   
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