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A biocompatible microporous composite of PMMA (poly-methyl-methacrylate), PHEMA (poly-hydroxy-ethyl-methacrylate) and calcium hydroxide bone replacement graft material (Bioplant HTR Synthetic Bone) was evaluated in 16 maxillary molar and 10 mandibular molar Grade II furcations in 13 patients. Following initial preparation, full thickness flaps were raised to gain access to the furcations; mechanical hand and ultrasonic root and defect debridement and chemical tetracycline root preparation were performed; furcation and adjacent osseous defects in each patient were grafted with HTR Synthetic Bone; and the host flaps replaced or slightly coronally positioned. Weekly, then monthly deplaquing was performed until surgical re-entry at 6-12 months. Patients were then followed on approximate 3-month recalls for > or = 6 yr. Evaluation of the primary clinical outcome of furcation grade change showed that in the maxilla 5/16 furcations were clinically closed, 9/16 were Grade I, and 2/16 remained Grade II; while in the mandible 3/10 were clinically closed, 5/10 were Grade I, and 2/10 remained Grade II. Other significant clinical changes included decrease in mean horizontal furcation probing attachment level from 4.4 mm at surgery to 2.2 mm at re-entry to 2.0 mm at 6 yr, decrease in probing pocket depth from 5.4 mm at surgery to 3.0 mm at re-entry to 3.2 mm at 6 yr, and improvement in vertical clinical probing attachment level from 5.4 mm at surgery to 4.2 mm at re-entry to 4.1 mm at 6 yr (all p < 0.05 from surgery to re-entry and surgery to 6 yr, n.s. from re-entry to 6 yr via ANOVA). These favorable results with HTR polymer are similar to several reports with other graft materials and with GTR barriers, and suggest that HTR polymer may have a beneficial effect in the clinical management of Grade II molar furcations. 相似文献
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The present studies were designed to evaluate the developmental toxicity of chlorpropham in mice. The first study was conducted to determine administration time, and the second study was designed to evaluate dose-response effects. Chlorpropham was administered to pregnant mice by gavage on Days 8, 8.3, 9, 9.3, 10, and 11 of gestation at a level of 3000 mg/kg bw, and the females were killed on Day 18 of gestation. The administration on Day 8.3 of gestation induced the highest percentage of external malformations with brachyury occurring among more litters than in other groups. Chlorpropham was administered to pregnant mice by gavage at a level of 0 (control), 750, 1500, and 3000 mg/kg bw on Day 8.3 of gestation, and the females were killed on Day 18 of gestation. The total resorption rate was significantly increased in the 3000 mg/kg bw group. The average fetal body weight of each sex was significantly reduced in the 3000 mg/kg treatment group. The total incidence of external malformations was significantly increased in the two highest dose groups in a dose-related manner. Again brachyury was significantly increased in the 3000 mg/kg bw group. 相似文献
377.
NK Ayisi EK Wiredu T Sata C Nyadedzor VK Tsiagbe M Newman CN Cofie K Taneguchi 《Canadian Metallurgical Quarterly》1997,74(12):784-791
Ninety-nine patients at Center for Disease Control (CDC) clinical stage IV were studied. Twelve (12.12%) of these patients turned out to be HIV seronegative. Ten out of the 12 HIV negative patients were immunocompetent whereas the other two had proportional decreases in both CD4+ and CD8+ T-lymphocytes. HIV-1, HIV-2, and dual infection, were detected in 51.5%, 2%, and 22.2% respectively of clinical AIDS patients. The other 12.12% of clinical AIDS patients were indeterminate for HIV antibodies. All HIV positive patients with the exception of two, were immunocompromised with respect to CD4+ and CD8+ T-lymphocyte counts. Two healthy spouses and three children of patients who died from the disease were seronegative for HIV antibodies. Herpes simplex virus type 2 (HSV-2) and cytomegalovirus (CMV) antibody titres were higher in HIV infected than uninfected blood. Patients with chronic diarrhoea, lymphadenopathy, pneumonia, and tuberculosis, either alone or in combination of two or more of such symptoms, were found to be more likely to be confirmed by serology and immunology as definitive AIDS patients in Ghana. In postmortem studies on 20 patients, pneumonia due to tuberculosis constituted the major cause of death. Toxoplasmosis, cytomegaloviral eosophagitis and enteritis, and cryptococcosis were the major opportunistic infections detected. Programmed cell death (apoptosis) was found by the DNA gel electrophoresis method to be an unlikely major mechanism of accelerated culture induced death of PBMCs from CDC stage IV AIDS patients. 相似文献
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A 4 month old female German Shepherd was presented for the work-up of a heart murmur that has been detected by the referring veterinarian. Clinical examination and thoracic radiography showed an enlargement of the right ventricle, and an increased pulmonary perfusion. Echocardiography showed an interatrial communication (atrial septum defect), and colour Doppler allowed the confirmation of a left to right shunt. The article discusses the diagnostic possibilities of this rare congenital cardiac malformation in the dog. 相似文献
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