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61.
MD Margolin AG Cogan M Taylor D Buck TN McAllister C Toth BS McAllister 《Canadian Metallurgical Quarterly》1998,69(8):911-919
The posterior maxilla has traditionally been one of the most difficult areas to successfully place dental implants due to poor bone quality and close approximation to the maxillary sinus. Sinus augmentation procedures have become a viable means of assuring adequate bone for the placement of dental implants in this area. However, with the techniques currently employed, a considerable variation in the quality of bone attained with the sinus augmentation procedure exists. The purpose of this in vivo study was to evaluate the healing response and bone formation stimulated by 3 doses of recombinant human osteogenic protein-1 (rhOP-1), 0.25, 0.6, and 2.5 mg OP-1 per gram of collagen matrix; natural bone mineral; or collagen matrix alone (control) placed in the maxillary sinus of adult chimpanzees. Results were assessed using clinical, histologic, and radiographic techniques. Radiographic analysis of the computed tomography scans taken at 1 week, and 2.5, 4.5, and 6.5 months revealed a more rapid mineralization with the 2.5 mg OP-1/g collagen matrix and natural bone mineral treatment groups. The incremental bone mineral density (BMD) increase for these 2 treatments from 1 week to 2.5 months was over 2.5 times the increase found with the collagen matrix alone; these 2 treatments also had a higher BMD at the most superior slices evaluated when compared to the other 3 groups. Biopsy specimens were taken at 3.5, 5.5, and 7.5 months and for all 5 treatment groups bone formation was observed at all time points in the majority of the specimens. At 7.5 months the 2.5 and 0.6 mg OP-1/g collagen matrix treatment groups had an increase in the percent bone area when compared to the matrix alone control. In conclusion, these results demonstrate that sinus augmentation with natural bone mineral or 2.5 mg OP-1/g collagen matrix induce comparable radiographic and histologic evidence of bone formation and that both of these treatments performed superior to the control group of collagen matrix alone based upon all methods of evaluation. 相似文献
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Studies in laboratory animals have demonstrated that dietary supplements of organoselenium, 1,4-phenylenebis(methylene)selenocyanate (p-XSC) inhibit colon carcinogenesis. Diverse chemopreventive agents and clinically used anticancer drugs have been shown to induce apoptosis in colonic tumors. Inducing apoptosis is a key mechanism for the effectiveness of some chemopreventive agents; however, failure of apoptosis is now believed to contribute to the development of human cancer. In this study, we determined the number of apoptotic bodies in the colon tumors of rats fed a low-fat (LF) or a high-fat (HF) diet with or without p-XSC treatment. At 5 weeks of age, male F344 rats were divided into four groups, which were then maintained on one of the following diets: LF, 5% corn oil; HF, 23.5% corn oil; and LF and HF supplemented with 20 ppm p-XSC. In addition, the LF or HF diet with p-XSC supplements was administered either during the initiation stage or postinitiation. At 7 weeks of age, all rats except those intended for vehicle (normal saline) treatment were given 15 mg/kg of body weight of azoxymethane once weekly for 2 weeks. The animals were sacrificed 38 weeks after carcinogen treatment, and their colonic tumors were examined for appearance of apoptosis. The LF diet significantly increased the percentage of apoptosis as compared to the HF diet; the percentage of apoptosis in LF and HF diets were 12.4 and 2.9. The colon tumors that were present in the groups fed p-XSC together with a LF or a HF diet after carcinogen administration (postinitiation period) had a higher number of apoptotic bodies than those that were present in the animals fed p-XSC before carcinogen treatment (initiation period). The extent of apoptosis was weak when p-XSC was given with a HF diet (4.4%) during the initiation phase, but it was high significant when p-XSC was administered with LF diet (25.2%). Taken together, our data suggest that administration of LF diet supplemented with p-XSC increases apoptosis as compared to a HF diet alone. 相似文献
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J Barrette R Bellwied P Braun-Munzinger WE Cleland T Cormier G Dadusc G David J Dee O Dietzsch M Fatyga SV Greene JV Germani JR Hall TK Hemmick N Herrmann RW Hogue B Hong K Jayananda D Kraus BS Kumar R Lacasse D Lissauer WJ Llope TW Ludlam R Majka SK Mark JT Mitchell M Muthuswamy E O'Brien C Pruneau FS Rotondo da Silva NC J Simon-Gillo U Sonnadara J Stachel H Takai EM Takagui TG Throwe L Waters C Winter D Wolfe CL Woody N Xu Y Zhang Z Zhang C Zou 《Canadian Metallurgical Quarterly》1995,52(5):2679-2683
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OBJECTIVE: The authors examined the efficacy of intramuscular flunitrazepam compared with intramuscular haloperidol for the immediate control of agitated or aggressive behavior in acutely psychotic patients. METHOD: Twenty-eight actively psychotic inpatients, aged 20-60 years, who were under treatment with neuroleptic agents were selected for the study. Each was randomly assigned on a double-blind basis to receive either 5 mg i.m. of haloperidol (N=13) or 1 mg i.m. of flunitrazepam (N=15) during an aggressive event. Verbal and physical aggression was measured over time with the Overt Aggression Scale. Patients were also rated with the Brief Psychiatric Rating Scale and the Clinical Global Impression scale. RESULTS: Both flunitrazepam and haloperidol exhibited acute antiaggressive activity. This beneficial effect, as assessed by the Overt Aggression Scale, was obtained within 30 minutes. CONCLUSIONS: Intramuscular flunitrazepam may serve as a convenient, rapid, safe, and effective adjunct to neuroleptics in reducing aggressive behavior in emergency psychiatric settings. 相似文献
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PURPOSE: To evaluate the efficacy of topical mitomycin C in treating conjunctival and corneal epithelial dysplasia and neoplasia. METHODS: Seven eyes of seven patients with conjunctival and corneal epithelial dysplasia and neoplasia were treated with one drop of topical mitomycin C 0.04% four times a day for 7 days in alternate weeks. The patients' charts were reviewed retrospectively. Patients with either multiple recurrences or extensive ocular surface involvement were treated. In all eyes, the diagnosis of epithelial dysplasia or neoplasia was confirmed by histopathology before the onset of therapy. Patients were examined at least every 14 days during treatment and examined at intervals after completion of treatment. RESULTS: With topical mitomycin C, six eyes of seven patients had complete clinical regression of their conjunctival and corneal epithelial dysplasia and neoplasia. One eye of one patient had partial clinical regression of conjunctival and corneal epithelial dysplasia. Follow-up after completion of topical mitomycin C therapy and excision of residual disease ranged from 2 to 16 months (mean, 9 months; SD, 4.3 months) and was without clinical sign of recurrence. Topical mitomycin C therapy was associated with transitory ocular discomfort, conjunctival injection, tearing, photophobia, and punctate epithelial keratopathy. CONCLUSION: In this small series of eyes, topical mitomycin C was effective as a treatment for conjunctival and corneal epithelial dysplasia and neoplasia. 相似文献
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