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排序方式: 共有747条查询结果,搜索用时 15 毫秒
1.
K.A. Eaton F.M. Rimini E. Zak D.J. Brookman L.M.A. Hopkins P. J. Carmell LG. Yates C. A. Morrice B.A. Lall H. N. Newman 《Journal of clinical periodontology》1997,24(3):189-197
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth. 相似文献
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. 相似文献
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G. Griffiths R. Lall S. Chatfield A. Short P. Mackay P. Williamson J. Brown M. Levene 《Archives of disease in childhood. Fetal and neonatal edition》1997,76(3):F190
AIM—To evaluate the role of recombinant human erythropoietin (R-HuEpo) in reducing iron infusion, which may exacerbate free radical damage, leading to chronic lung disease.METHODS—A multicentre, randomised, placebo controlled, double blind study was carried out in four neonatal intensive care units in Yorkshire. Infants were randomly allocated and received either R-HuEpo (480 U/kg/wk) or placebo by twice weekly subcutaneous injection. The primary outcome measure was the number of days on respiratory support and a secondary outcome the number of blood transfusions required.RESULTS—Forty two very low birthweight (VLBW) infants were randomly allocated. There was little difference in the need for respiratory support one month after randomisation, but subsequently there was a trend towards a reduction in the proportion requiring respiratory support in the R-HuEpo group (difference at three months ?0.50, 95% confidence interval ?1.00, 0.17). During stay in hospital, the median number of blood transfusions was lower for infants in the R-HuEpo group (difference in medians ?2, 95% CI ?4, 0). The study was stopped early because of failure to recruit babies at the expected rate.CONCLUSIONS—R-HuEpo seems to reduce the number of days in oxygen for ill VLBW infants. These data could be used to construct a larger multicentre study to evaluate this effect further. 相似文献
9.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
10.
Mutation of the p53 tumor suppressor gene in spontaneously occurring osteosarcomas of the dog 总被引:8,自引:0,他引:8
Inactivation of the p53 tumor suppressor gene has been implicated in the
pathogenesis of numerous human cancers, including osteosarcomas.
Appendicular osteosarcomas of the dog appear to be a good model for their
human equivalent with regard to biologic behavior, epidemiology and
histopathology. We individually screened exons 5-8 of the p53 gene for
mutations in 15 canine appendicular osteosarcomas using 'Cold' SSCP to
compare the role of this gene in human and canine osteosarcoma
tumorigenesis. Seven of the tumors (47%) exhibited point mutations, with
one tumor possessing two mutations within different exons. Of these, seven
were missense mutations and the eighth was a 'silent' mutation potentially
affecting the exon 6-7 splicing region. Five of the missense mutations were
located in highly conserved regions IV and V, while another corresponded
with the highly conserved codon 220 mutational hotspot located outside the
conserved domains. The locations and types of mutations were nearly
identical to those reported in human cancer. These findings provide strong
evidence of the involvement of p53 mutations in the development of canine
appendicular osteosarcomas. Canine osteosarcomas appear to be a promising
model for their human equivalent on a clinical, pathologic, and molecular
level.
相似文献