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41.
Abstract A former double-blind study evaluated the effect of a 14–day period of systemic and topical folate supplementation on gingival inflammation during pregnancy (Pack & Thomson 1980). The current experiment was similar to the earlier one except that supplementation was for 28 days during the eighth month only. Thirty women during their 32nd week of pregnancy were randomly divided into three equal groups. Control Group A received placebo mouthwash (MW) and placebo tablets; Group B received placebo MW and one 5 mg folate tablet daily; Group C received placebo tablets and rinsed with folate MW twice daily for 1 min. At the beginning and end of the experimental period, oral status was determined using a plaque index (PII) and a gingival index (GI). Each subject furnished a 1–week diet record which was analysed for dietary folate. No differences in parameters existed between groups at the commencement of the study except for folate levels which were lower in Group B. Results confirmed the findings of the former experiment. Group C showed highly significant improvement in Gl despite no significant changes in PII (0.00 < p < 0.01), whilst in Group B, changes in gingival health were not statistically significant (0.05 < p < 0.10). No significant changes were demonstrated in Group A. Folate levels increased significantly in Groups B and C. Dietary folate was similar in all groups. 相似文献
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Pack AM Morrell MJ Marcus R Holloway L Flaster E Doñe S Randall A Seale C Shane E 《Annals of neurology》2005,57(2):252-257
Antiepileptic drugs, particularly cytochrome P450 enzyme inducers, are associated with disorders of bone metabolism. We studied premenopausal women with epilepsy receiving antiepileptic drug monotherapy (phenytoin, carbamazepine, valproate, and lamotrigine). Subjects completed exercise and nutrition questionnaires and bone mineral density studies. Serum was analyzed for indices of bone metabolism including calcium, 25-hydroxyvitamin D, parathyroid hormone, insulin growth factor I, insulin binding protein III, and bone formation markers, bone-specific alkaline phosphatase, and osteocalcin. Urine was analyzed for cross-linked N-telopeptide of type I collagen, a bone resorption marker. Calcium concentrations were significantly less in subjects receiving carbamazepine, phenytoin, and valproate than in those receiving lamotrigine (p = 0.008). Insulin growth factor-I was significantly reduced in subjects receiving phenytoin compared with those receiving lamotrigine (p = 0.017). Subjects receiving phenytoin had significantly greater levels of bone-specific alkaline phosphatase (p = 0.007). Our results demonstrate that phenytoin is associated with changes in bone metabolism and increased bone turnover. The lower calcium concentrations in subjects taking carbamazepine or valproate compared with those taking other antiepileptic drugs suggest that these antiepileptic drugs may have long-term effects. Subjects receiving lamotrigine had no significant reductions in calcium or increases in markers of bone turnover, suggesting this agent is less likely to have long-term adverse effects on bone. 相似文献
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BACKGROUND: We have not found any reports on the effect of physiotherapy after knee replacement. PATIENTS AND METHODS: In a prospective randomized controlled trial, we randomized two groups to receive or not receive outpatient physiotherapy following total knee arthroplasty. 120 patients were recruited over 2 years, each followed up for 1 year. Inclusion criteria were age between 55-90 years, less than 40 degrees of fixed flexion contracture and the ability to walk at least 10 meters unaided preoperatively with monoarticular arthrosis. RESULTS: We found no statistically significant benefit of outpatient physiotherapy at any of the three times measured. After adjusting for baseline differences between the two treatment groups, the mean difference in knee flexion 1 year postoperatively was only 2.9 degrees. This mean difference is of no clinical significance. INTERPRETATION: We concluded that in a preselected group of patients following primary total knee arthroplasty, inpatient physiotherapy with good instructions and a well-structured home exercise regime can dispense with the need for outpatient physiotherapy. 相似文献
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Kang JL Pack IS Hong SM Lee HS Hah JS Nam W Leonard S Castranova V 《Toxicology and applied pharmacology》2001,172(2):140-149
One proposed mechanism for the development of silica-induced fibrosis is prolonged pulmonary inflammation and lung damage resulting from the secretion of reactive mediators from alveolar macrophages. Metalloporphyrins have antioxidative and antiinflammatory activities. However, the molecular basis for the antiinflammatory action of zinc tetrakis(N-methyl-4'-pyridyl) porphyrinato (ZnTMPyP) has not been elucidated. The objective of this study was to determine whether ZnTMPyP exhibited the ability to inhibit the production of reactive oxygen species (ROS), the activation of NF-kappaB, or the secretion of IL-1 in RAW 264.7 cells, and whether such inhibitory activity was related to the ROS-scavenging ability of ZnTMPyP. The results indicate that, although ZnTMPyP is not cytotoxic to RAW 264.7 cells, it is a potent inhibitor in ROS production by RAW 264.7 cells in response to various stimulants, such as silica, zymosan, or phorbol myristate acetate. ZnTMPyP is also effective in reducing stimulant-induced DNA-binding activity of NF-kappaB and silica-induced tyrosine phosphorylation of IkappaB-alpha. ZnTMPyP also inhibits LPS-induced IL-1 production. However, ZnTMPyP exhibits relatively weak ability to directly scavenge hyroxyl or superoxide radicals. On the basis of effective concentrations of ZnTMPyP, these results suggest that ZnTMPyP directly acts as an inhibitor of cellular activation in addition to exhibiting an antioxidant effect. Therefore, it is suggested that further studies concerning the effects of ZnTMPyP using in vivo oxidative stress models or its effects on the cytotoxic process of human diseases associated with lung inflammation and injury are warranted. In addition, ZnTMPyP may be a useful tool to investigate the molecular mechanisms involved in stimulant-induced signal pathways. 相似文献
50.
Integration of periorbital titanium implants in irradiated bone: case report and histologic evaluation 总被引:1,自引:0,他引:1
Pack M Röser K Eufinger H 《The International journal of oral & maxillofacial implants》1999,14(2):290-294
Extraoral implants are used increasingly frequently in the wake of ablative tumor surgery and adjuvant radiation or chemotherapy for craniofacial rehabilitation with facial prostheses and epitheses. However, high rates of nonintegration and implant loss have been reported for extraoral implants, especially for those in the periorbital region following irradiation. This case report and corresponding histologic evaluation describe the osseointegration pattern in irradiated periorbital bone, based on the example of 3 retrieved, clinically integrated, stable titanium screw implants. 相似文献