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The purpose of this study was to assess the value of ultrasound in the measurement of periodontal bone morphology. Four patients scheduled for periodontal surgery were selected for the study. The Ocu-Scan 400 machine was used and adjusted according to the manufacturer's instructions. Teeth involved in the study were measured on the facial aspect at three different points: mesial, midfacial and distal (except one tooth measured only at the mesial point). Two different presurgical measurements were made with the use of ultrasound. The distance between the gingival margin and the crest of alveolar bone was measured during the surgical procedure. No correlation could be made between the different measurements obtained. From the results the following was concluded: measurement of alveolar bone topography with the presently available ultrasound probe is not accurate, and ultrasound measurement is a fast and painless procedure.  相似文献   
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BACKGROUND: The aim of this study was to evaluate the effect of nicotine on the strength of attachment of human gingival fibroblast cells to glass and non-diseased human root surfaces. METHODS: Human gingival fibroblast cells (HGF) were trypsinized, suspended in RPMI 1640 medium, and incubated with autoclaved human root and glass sections and nicotine (NIC) concentrations of 0 (control), 25, 50, and 100 ng/ml for 1 week. HGF attached and grew on glass and root surfaces for 4 weeks at all NIC concentrations. HGF cultures were subjected to a rotary shaker machine for 30 minutes to test the strength of attachment of these cells at 100, 150, and 200 rpm. The root and glass sections were examined at 48 hours by light microscopy. RESULTS: Control groups exhibited a monolayer of long, spindle-shaped fibroblasts with a parallel alignment and minimal overlapping. With a concentration of NIC of 50 or 100 ng/ml as well as with increasing "speeds," the number of cells attached to these surfaces decreased dramatically. When 200 rpm was used for both groups at all NIC concentrations, very few HGF remained attached to these surfaces. CONCLUSIONS: This study showed that the nature of cell attachment to either glass or root surfaces is altered by nicotine, and marked detachment was noted when nicotine exposure was coupled with vigorous agitation at different rpm. Marked detachment noted in all specimens at 200 rpm indicates that this speed is excessive for use in subsequent experimentation.  相似文献   
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Nausea and emesis are common side effects of opioid drugs administered for pain relief in cancer patients. The aim of this study was to compare the anti-emetic efficacy and safety of ondansetron, placebo and metoclopramide in the treatment of opioid-induced nausea and emesis (OIE) in cancer patients. This was a multinational, multicentre, double-blind, parallel group study in which cancer patients who were receiving a full opioid agonist for cancer pain were randomised to receive one of oral ondansetron 24 mg once daily, metoclopramide 10 mg three times daily, or placebo. Study medication was started only if the patient experienced nausea and/or emesis following opioid administration. Efficacy and safety assessments were made over a study period of 24 h from the time of the first dose of anti-emetics/placebo. The study was terminated prematurely because of the difficulties in recruiting patients satisfying the stringent entry criteria. Ninety-two patients were included in the intent-to-treat population: 30 patients received placebo, 29 patients ondansetron and 33 patients metoclopramide. There was no statistically significant difference between the groups in the proportion achieving complete control of emesis (33% of patients on placebo, 48% on ondansetron and 52% on metoclopramide) or complete control of nausea (23% of patients on placebo, 17% on ondansetron and 36% on metoclopramide). Rescue anti-emetics were required in 8 of 33 patients on metoclopramide, 4 of 29 on ondansetron, and 3 of 30 on placebo. The incidence of adverse events was very low and similar in all treatment groups. Neither ondansetron 24 mg once daily nor metoclopromide 10 mg t.d.s. given orally was significantly more effective than placebo in the control of OIE in cancer patients.  相似文献   
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