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1.
BACKGROUND: The therapies for refractory ulcers on the oral mucosa are symptomatic and very unsatisfactory. We hypothesized that application of growth factors might be able to achieve successful remission of the lesion. We evaluated the effects of systemic administration and topical application of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on impaired wound healing of ulcers in the rabbit gingiva. METHODS: Almost uniform round ulcers could be created on the gingiva of the rabbits by chemical injury with acetic acid. When the submandibular glands were removed or i.v. injection of cisplatin (CDDP) and peplomycin sulfate was performed before ulcer formation, healing of the ulcers took longer than in untreated rabbits. To ascertain whether or not human EGF and bFGF affect rabbit cells, we first examined the effects of EGF and bFGF on the proliferation of the cells derived from rabbit gingiva. We then applied EGF or bFGF in these impaired healing models. RESULTS: EGF and bFGF promoted proliferation of the fibroblasts, and EGF also promoted proliferation of the keratinocytes isolated from gingival tissue of rabbits in vitro. Systemic injections of EGF and bFGF in rabbits, which had their submandibular glands removed, and topical application of bFGF accelerated healing of ulcers created in rabbits injected with CDDP and peplomycin sulfate. The ability of bFGF to promote the healing of ulcers was much greater than that of EGF. CONCLUSION: Basic FGF may be effective for refractory oral mucosal lesions.  相似文献   
2.
This study focuses on obtaining more information about the site of anastomosis, with three-dimensional examination using methylmethacrylate resin (Mercox) corrosion casts. Seventy microvascular anastomoses were performed in Wistar albino rats, divided into two groups before sacrifice. In Group 1 (35), Mercox was injected into the vessels, whereas in Group 2 (35), the tissues were prepared without injecting Mercox. Both groups were compared under the scanning electron microscope (SEM). The SEM preparation in Group 1 was simple, easy, and artifacts were significantly minimized. The anastomotic site could be well appreciated in three-dimensional views. Clear negative imprints of the endothelial surface were achieved without any breakage in the Mercox corrosion cast, and it can be reliably used in the evaluation of small vessel anastomosis.  相似文献   
3.
PURPOSE: The purpose of this study was to test the functional and histologic fate of costochondral grafts (CG) in temporomandibular joint (TMJ) reconstruction for unilateral ankylosis in the sheep. MATERIALS AND METHODS: Five pure-bred adult Merino sheep were used. Ankylosis was induced by articular damage, disc removal, and placement of a bone graft. At 3 months, a gap arthroplasty was performed with a CG from the thirteenth rib. The sheep were sacrificed 3 months after CG reconstruction. The range of jaw movements were recorded at first operation, at lysis of ankylosis, and at sacrifice. The joints were examined radiologically, macroscopically, and histologically. RESULTS: All sheep showed a decrease in masticatory function, as shown by weight loss and decreased jaw opening, during the ankylosis period. On release, they regained weight and increased the range of jaw movement. Histologically, the joint space was filled with fibrous tissue. However, the partial spaces around the CG head were covered by fibrous tissue and/or fibrous cartilage. CONCLUSIONS: This study shows that, when CGs are used with a gap arthroplasty in a fibrous and bony ankylosed TMJ, masticatory function is restored.  相似文献   
4.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
5.
There have only been a few studies on the role of mineral intake in tooth loss. We investigated the association between mineral intake and the prevalence of tooth loss in Japan. We used the baseline data on 1002 pregnant women who were enrolled in the Osaka Maternal and Child Health Study between November 2001 and March 2003. Tooth loss was defined as the previous extraction of one or more teeth. Nutrient intake was assessed by a validated diet history questionnaire. Prevalence odds ratios and confidence intervals were estimated by applying a multiple logistic regression model. The adjusted odds ratio upon comparison of the highest quartile with the lowest quartile of magnesium intake was 0.64 (95% confidence interval, 0.42-0.99), showing a tendency for an inverse dose-response relationship (p for linear trend = 0.05). There were no associations between the level of consumption of calcium, phosphate, iron, zinc, or copper and tooth loss. The present findings suggest that intake of magnesium is related to reduced prevalence of tooth loss among young Japanese women.  相似文献   
6.
12 giant intracranial aneurysms were studied by MRI. Intraluminal thrombosis was observed in 9 aneurysms. Thrombosis was found more frequently in larger aneurysms. Thrombi were formed posteriorly or inferiorly in the lumen of 4 among 5 IC-cavernous aneurysms. Location of the neck of the aneurysms and stagnation of blood flow influenced by gravity may be causative factors determining the location of thrombi. In 6 aneurysms intraluminal thrombi were inhomogeneous on MRI, suggesting that the thrombi had been formed at different times. New thrombi were formed between the aneurysmal wall and the old thrombus in 3 cases. Dissection of the aneurysmal wall by residual blood flow in the lumen or hemorrhage in the aneurysmal wall may be one of the growth mechanisms of giant intracranial aneurysms.  相似文献   
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8.
A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.  相似文献   
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10.
To elucidate the mechanisms of the intracellular signal transduction elicited with bradykinin in NG108-15 neuroblastoma x glioma hybrid cells, we examined the activation of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) by bradykinin stimulation. When the extract of NG108-15 cells was immunoprecipitated with the affinity-purified antibody to brain CaM kinase II, a 50-kDa protein in the immunoprecipitate mainly became autophosphorylated in a Ca2+/calmodulin-dependent manner. The results suggest that the 50-kDa protein is the subunit of CaM kinase II in NG108-15 cells. The Ca2+/calmodulin-independent activity (autonomous activity) of the enzyme increased twice within 10 s by stimulation with 1 microM bradykinin in the cells. The increase in the autonomous activity of the enzyme had two phases: the transient early-peak phase and the long late-plateau phase. The former was abolished by the pretreatment of the cells with 10 mM caffeine or 20 microM BAPTA-AM, and the latter was abolished by the removal of the extracellular Ca2+ with 1 mM EGTA or by the pretreatment with 1 microM nifedipine. Stimulation of 32P-labeled NG108-15 cells with 1 microM bradykinin increased the autophosphorylation of CaM kinase II and this increase was abolished by pretreatment with caffeine or BAPTA-AM. These results suggest that CaM kinase II is activated via the inositol phospholipid signaling pathway induced with bradykinin in NG108-15 cells.  相似文献   
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