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971.
11 patients with lingual carcinoma were treated by artery chemoembolization with 100 mg CDDP-AMS microcapsules (CDDP 13.6 mg) through lingual artery, and the average diameter of microcapsules was 56.3 microns. There was no obvious carcinoma cell or carcinoma tissue in pathologic specimens of the tissue after 4 weeks of treatment. After 5-6 weeks of chemoembolization, the clinical tumor ulcer disappeared, but it was difficult to judge the change of the tumor because of local fiber tissue. After 6 months, by observation of 4 patients whose tumors had not been excised, it was found that the infiltuation mass of primary carcinoma disappeared and tongue body became soft. It suggests that artery chemoembolization with CDDP-AMS microcapsules is an efficient way of lingual carcinoma treatment.  相似文献   
972.
This study investigates a potential role for TGFβ1 in the pathogenesis of cyclosporin A-induced gingival overgrowth (CsA-OG). TGFβ1 was localized immunohistochemically in the connective tissue of both normal gingiva and CsA-OG. Intense staining for TGFβ1 was detected at the tips of the dermal papillae of the overgrown gingiva. In addition, fibroblasts derived from healthy gingiva and fibroblasts derived from CsA-OG were cultured both as monolayers or embedded in a 3D-collagen gel. Fibroblast activity was monitored in terms of protein and collagen production in the presence of (i) 1 ng/ml TGFβ1 (ii) 500 ng/ml CsA, or (iii) 500 ng/ml CsA and 1 ng/ml TGFβ1. In monolayer culture TGFβ1 significantly increased protein and collagen production in all cell strains (p<0.05); however, there was no difference in response between fibroblasts from overgrown and healthy tissue. The production of both protein and collagen was significantly lower in the presence of the combination of CsA and TGFβ1 when compared with the maximal stimulation produced by TGFβ1 alone. In gel, TGFβ1 significantly elevated matrix production by all overgrown cell strains (p<0.05) but had little or no effect on the normal cell strains. The combination of CsA and TGFβ1 in gel cultures reduced protein and collagen production by overgrown cell strains compared with TGFβ1 alone. It is concluded that the cellular activity of gingival fibroblasts is dependant on culture conditions and that fibroblasts derived from overgrown gingival tissue are more responsive to TGFβ1 than normal gingival fibroblasts when cultured in type I collagen gel.  相似文献   
973.
974.
975.
Abstract. The immunogenic potential of a root canal disinfectant (FA 6/25) with a reduced formaldehyde concentration (one-third of that in Formocresol) was studied after application to one incisor tooth per guinea-pig, both presensitized and non-presensitized. Skin reaction after occlusive patch testing was studied. Several indications were found that the disinfectant caused an allergic reaction.  相似文献   
976.
Daily variations in occlusal contacts   总被引:1,自引:0,他引:1  
In this study the location and severity of occlusal contacts in the morning and evening on 3 separate days were recorded for 10 women. Biofeedback therapy was used after evening recordings to encourage muscle relaxation. The findings suggest that occlusion and occlusal contacts change throughout the day and depend on the physical state of the masticatory muscles and the mental state of the patient. Although this conclusion is understandable, its effects on the philosophies of occlusal rehabilitation are questionable. Further studies are needed to evaluate the significance of the contact variations in occlusal restorations placed at different times.  相似文献   
977.
978.
Rats were fed a low calcium diet deficient in vitamin D for 14 days. Changes in alkaline phosphatase activities in odontoblasts dissected out from incisor teeth were studied biochemically. A strong increase in pNPP-ase, PPi-ase, total ATP-degradation and Ca2+- ATPase was observed in the deficient animals compared with animals fed a control diet.  相似文献   
979.
Actinomyces viscosus 19246, T14V and T14AV, Streptococcus mutans and Streptococcus sanguis consumed complement in vitro. Complement (C) profile analysis revealed that C4 and C3–9 were consumed concomitantly in unadsorbed human serum. In serum from which naturally occurring agglutinating antibodies had been removed, the same microorganisms caused C3–9 consumption in the absence of a demonstrable loss of C4 activity. Congenitally C4-deficient guinea-pig serum (C4D) supported a similar consumption of C3–9. The Gram-positive plaque microorganisms tested activated serum complement by the classical as well as the alternate pathways. Dental plaque microorganisms may cause a similar activation of gingival crevicular fluid complement in vivo, thus resulting in complement-mediated inflammatory processes.  相似文献   
980.
Several physical properties of nine commercial root canal sealers were evaluated in vitro and were compared with those of two experimental endodontic materials based on polycarboxylate formulations. Flow, setting time, compressive strength, radiopacity, adhesion to root dentin, and solubility were evaluated. The zinc oxideeugenol root canal sealers were typically of low strength and high solubility. These sealers and the Diaket polyvinyl resin sealer showed no adhesion to dentin. The epoxy resin AH26 showed superior properties with respect to strength, flow, radiopacity, and adhesion; solubility of this material was high. The polycarboxylate formulation showed significantly higher values over the commercial sealers in properties of strength, adhesion, and reduced solubility. The tensile adhesive bond strength of the polycarboxylate to root dentin was twice that of AH26. A wide variation in properties of the commercial materials tested showed the empirical nature of these "sealers." Further testing of polycarboxylate endodontic sealers is indicated.  相似文献   
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