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981.
982.
983.
Few studies have detected periodontal pathogens in young children, and when detected the prevalence has been relatively low. In this epidemiological study, we determined the prevalence of periodontal pathogen colonization in young children and examined the relationship between periodontitis in mothers and detection of periodontal pathogens in their children aged 18–48 months. Children were selected and enrolled randomly into the study; tongue and gingival/tooth plaque samples were harvested and analyzed by DNA probe checkerboard assay for Porphyromonas gingivalis and Bacteroides forsythus. Clinical measurements included a gingival bleeding score in the children and a periodontal screening and recording (PSR) score in the mothers. Mothers having one or more periodontal sites with probing depths > 5.5 mm were classified as having periodontitis. In this population, 71% (66/93) of the 18‐ to 48‐month‐old children were infected with at least one periodontal pathogen. Detection rates for children were 68.8% for P. gingivalis and 29.0% for B. forsythus. About 13.8% (11/80) of children had gingival bleeding in response to a toothpick inserted interproximally. Children in whom B. forsythus was detected were about 6 times more likely to have gingival bleeding than other children. There was no relationship between bleeding and detection of P. gingivalis. 17.0% (16/94) of the mothers had periodontitis. When all mother–child pairs were considered, the periodontal status of the mother was found not to be a determinant for detection of periodontal pathogens in the floral samples from the children. However, the odds ratio that a daughter of a mother with periodontitis would be colonized was 5.2 for B. forsythus. A much higher proportion of children in this population were colonized by P. gingivalis and/or B. forsythus than has been previously reported for other populations. A modest level of association between manifestations of periodontitis in mothers and detection of B. forsythus in their daughters was observed.  相似文献   
984.
A 46-year-old woman with extensive skeletal metastases from primary breast carcinoma was examined scintigraphically using99mTc HMDP. The skeletal metastatic lesions, except for the mandible and hip joint, were clinically asymptomatic and hardly detected radiographically. Marked accumulation of99mTc HMDP was shown in both the asymptomatic and symptomatic lesions, and scintigraphy is also a useful imaging modality for the identification of whole body metastatic bone lesions, especially in the early stage.  相似文献   
985.
A study of dental caries was carried out involving 1537 mothers who attended St David's Hospital, Gwynedd, between July 1986 and July 1987 for their confinement. The study was 'blind' in respect of residence. The mean DMFT value for mothers with continuous residence in the non-fluoridated Gwynedd mainland was 13.6 and the mean DMFT value for mothers living in the Anglesey Health Unit who had consumed fluoridated mains water from birth was 30% lower at 9.5 (P less than 0.0001). The confidence interval for the difference between means was 3.4-4.9. The samples from the two areas showed no significant differences in social class and age group structures. The percentage of Anglesey mothers with DMFT exceeding 15 was less than one-sixth of that for mainland mothers and the percentage of those with DMFT less than 6 was three times greater. The mean DMFS value for occlusal sites in premolars was 3.9 for mainland Gwynedd and for Anglesey 52% less at 1.9 (P less than 0.0001) with a confidence interval of 1.6-2.4. For smooth surface sites in posterior teeth, the difference was not as pronounced, with a mean DMFS value for mainland of 20.3 and for Anglesey 42% less at 11.8 (P less than 0.0001) with a confidence interval of 7.5-9.6. The results showed that child-bearing women continued to enjoy important benefits from water fluoridation into their early thirties.  相似文献   
986.
Digital subtraction arthrography and arthrofluoroscopic dynamic observation were performed for seventy cases with TMJ dysfunction syndrome. A comparative study between the findings of digital subtraction arthrography and the operative findings was carried out for eleven cases who underwent surgery. It has been found that digital subtraction arthrography can overcome the disadvantages of conventional arthrography and has important diagnostic value for TMJ dysfunction syndrome, especially for disc perforation. In addition. The procedure of digital subtraction arthrography, the normal and abnormal manifestations of digital subtraction arthrograms were described in the present study.  相似文献   
987.
This study examined the recovery of secretory IgA (S‐IgA) in saliva after hematopoietic stem cell transplantation (HSCT) in 35 children and young people between the ages of 3 and 27 years (mean = 13.6), and compared this recovery with that of serum immunologic constituents. Reference values for human salivary S‐IgA in saliva were obtained from 77 healthy control subjects between the ages of 7 and 25 years (mean = 11.4). In the 35 patients, a nadir of secretory IgA concentrations in saliva (S‐IgA) was observed between the 3rd and the 4th month, and a return to normal values 1 year after HSCT. Serum IgA concentrations reached their nadir in the 6th month, and normalized in the 18 months after HSCT. The recovery of T‐helper cells (CD4+/3+) was also delayed to beyond 18 months. We found a significant correlation between the reconstitution pattern of S‐IgA and that of T‐helper lymphocytes, but no correlation was found between the post‐transplant evolutions of S‐IgA and serum IgA, or between S‐IgA and T‐helper cells. The recovery of S‐IgA was more rapid than that of serum IgA and appeared to be T‐helper cell independent.  相似文献   
988.
989.
The effect of ketoprofen creams on periodontal disease in rhesus monkeys   总被引:1,自引:0,他引:1  
Ketoprofen creams were evaluated for the treatment of periodontal disease in a placebo-controlled, double-blind study in the rhesus monkeys, Macaca mulatta. Two formulations containing ketoprofen (1%), with or without vitamin E, were evaluated against appropriate controls (8 monkeys per group). Two weeks prior to treatment, the animals received prophylaxis on only the left side of the mouth (spontaneous model). Selected teeth on the right side of the mouth were ligated (ligature model). The creams were administered to the gingiva once daily at a standard dose of 1.8 ml per monkey for 6 months. Clinical assessments were made 2 wk before initiation, at baseline and 1, 2, 3 and 6 months post-treatment. The clinical parameters included plaque formation, gingival redness, edema, bleeding on probing and Ramfjord Attachment Level measurements (RAL). Radiographs were taken at 2 wk before initiation, baseline and at 3 and 6 months post-treatment. Digital subtraction radiography was used to measure vertical linear bone loss along the interproximal root surfaces of the left and right mandibular first molars. Gingival crevicular fluid (GCF) was collected for biochemical assays on PGE2, TxB2, LTB4, IL-1β and TNFα. There were no significant differences among groups with respect to gingival indices. Radiographic data demonstrated significant positive effects on bone activity in both groups treated with ketoprofen formulations with improvement over time in the ligature model (0.01 ≤p≤ 0.04). The placebo group exhibited bone loss of 1.96±0.48 and 1.40±0.56 mm per site at 3 and 6 months, respectively. The group treated with ketoprofen cream showed an apparent bone gain of 0.28±0.41 and 0.78±0.47 mm per site at 3 and 6 months, respectively. The group treated with ketoprofen cream containing vitamin E showed a mean bone loss of 0.41–0.48 mm per site at 3 months with improvement to an apparent bone gain of 0.31±0.44 mm per site at 6 months. The biochemical data demonstrated early and significant suppression of GCF-LTB4 by both ketoprofen formulations at 1 month, which preceded the significant suppression of GCF-PGE2 at 2 and 3 months in the ligature model (p≤0.003) and at 2 to 6 months in the spontaneous model (p≤0.02). We conclude that ketoprofen at 1% level in suitable topical vehicles can effectively inhibit GCF-LTB4 and GCF-PGE2 and positively alter alveolar bone activity in the ligature-induced model of periodontitis in the monkey.  相似文献   
990.
A statistical thermodynamical approach to the study of anion-induced adsorption of Cd(II) from halide solutions is presented. The simultaneous adsorption of metal complex and ligand is introduced in the isotherms by considering two possible mechanisms — competitive adsorption and surface complexation. These isotherms have been tested for the system Cd(II) in KBr at several ionic strengths. The experimental surface excesses of Cd(II) calculated from single-step chronocoulometry can be simulated, giving an explanation for the desorption of the metal complex at positive potentials. Also, the change in ligand adsorption promoted by the adsorption of the metal complex has been calculated. Both approaches lead to the conclusion that the anionic tricoordinate metal complex CdBr3? and the tetracoordinate CdBr42? are the absorbed species on the electrode surface, with CdBr42? dominating at higher bromide concentrations.  相似文献   
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