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1.
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   
2.
AIMS: To study if established diagnostic threshold values for gestational diabetes based on a 75-g, 2-h oral glucose tolerance test can be supported by maternal and perinatal outcomes. METHODS: Historical cohort study of 3260 pregnant women examined for gestational diabetes on the basis of risk indicators. Information on oral glucose tolerance test results and clinical outcomes were collected from medical records. RESULTS: There was an increased risk of delivering a macrosomic infant in women with 2-h capillary blood glucose of 7.8-8.9 mmol/l compared with women with 2-h glucose < 7.8 mmol/l. Despite treatment, 2-h glucose of 9.0-11.0 mmol/l and > or = 11.1 mmol/l were both associated with increased rates of macrosomia, spontaneous preterm delivery, hypertensive complications, and neonatal hypoglycaemia. Adverse outcomes tended to be more frequent in women with 2-h glucose > or = 11.1 mmol/l than in women with 2-h glucose of 9.0-11.0 mmol/l. CONCLUSIONS: The risk for several maternal and perinatal complications increased with the diagnostic threshold for 2-h glucose. Large-scale blinded studies are needed to clarify the question of a clinically meaningful diagnosis of gestational diabetes mellitus. Until these results are available, a 2-h threshold level of 9.0 mmol/l after a 75-g oral glucose tolerance test seems acceptable.  相似文献   
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Abstract Periodontal diseases may be the first clinical sign of human immunodeficiency virus (HIV)-infection. Since the immunosuppression and subsequent susceptibility may alter the responses of the oral tissues as well as the microflora, both periodontal treatment and result of therapy may be modified. The periodontal diseases in HIV-seropositive patients include common as well as less conventional forms of gingivitis and periodontitis, and bacteria, mycotic and viral infections are seen. Neoplasias may also involve the periodontium; most common are Kaposi's sarcoma and non-Hodgkin's lymphoma. Recent studies of unselected groups of patients indicate that periodontal health in at least some groups of HIV-seropositive patients is better than previously reported.  相似文献   
5.
Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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6.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA.  相似文献   
7.
Y chromosome deletions encompassing the AZFc region have been reported in 13% of azoospermic men and 7% of severely oligozoospermic men. We examined the impact of these Y deletions on the severity of testicular defects in 51 azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after testicular sperm extraction (TESE) and 30 men with severe oligozoospermia undergoing ICSI after ejaculation of spermatozoa. In addition, five azoospermic patients shown previously to have Y chromosome deletions underwent histological evaluation of their previously obtained testis biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y chromosome AZFc region. Of these 10, five had spermatozoa retrievable from the testis, and in two cases the wives became pregnant. Of the 41 azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa retrievable from the testis, and in 12 cases (29%) the wives became pregnant. Four of 30 (13%) severely oligozoospermic patients were found to be deleted for AZFc and in three (75%) of these pregnancy was achieved. The other 26 severely oligozoospermic couples who had no AZFc deletions underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The embryo implantation rate was not significantly different for azoospermic (22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the total of 19 infertile men who had Y chromosome deletions, 14 had deletions within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14 had some spermatozoa (however few in number) in the ejaculate or testis. Five of the Y-deleted men had deletions that extended more proximally on the Y chromosome, and in none of these could any spermatozoa be observed in either ejaculate or testis. These results support the concept that, in azoospermic or oligozoospermic men with Y chromosome deletions limited to intervals 6D-6F (AZFc), there are generally very small numbers of testicular or ejaculated spermatozoa. Larger Y deletions, including and extending beyond the AZFc region and encompassing more Y genes, tend to be associated with a total absence of testicular spermatozoa. In those cases where spermatozoa were retrieved, the presence of Y deletions had no obvious impact on fertilization or pregnancy rate.   相似文献   
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The bacterium Actinobacillus actinomycetemcomitans has been implicated in the pathogenesis of juvenile periodontitis as the etiologic agent on the basis of several lines of circumstantial evidence. A matter of extensive debate is whether A. actinomycetemcomitans is an exogenous contagious pathogen or an opportunistic pathogen that resides in the normal oral microflora. Here we show evidence of a single clone of A. actinomycetemcomitans isolated from multiple patients with juvenile periodontitis in members of families of African origin living in geographically widespread areas. The clone is characterized by a 530-bp deletion in the leukotoxin gene operon, resulting in a significantly increased production of leukotoxin.  相似文献   
10.
BackgroundEntrustable Professional Activities (EPAs) contain narrative ‘entrustment roadmaps’ designed to describe specific behaviors associated with different entrustment levels. However, these roadmaps were created using expert committee consensus, with little data available for guidance. Analysis of actual EPA assessment narrative comments using natural language processing may enhance our understanding of resident entrustment in actual practice.MethodsAll text comments associated with EPA microassessments at a single institution were combined. EPA—entrustment level pairs (e.g. Gallbladder Disease—Level 1) were identified as documents. Latent Dirichlet Allocation (LDA), a common machine learning algorithm, was used to identify latent topics in the documents associated with a single EPA. These topics were then reviewed for interpretability by human raters.ResultsOver 18 months, 1015 faculty EPA microassessments were collected from 64 faculty for 80 residents. LDA analysis identified topics that mapped 1:1 to EPA entrustment levels (Gammas >0.99). These LDA topics appeared to trend coherently with entrustment levels (words demonstrating high entrustment were consistently found in high entrustment topics, word demonstrating low entrustment were found in low entrustment topics).ConclusionsLDA is capable of identifying topics relevant to progressive surgical entrustment and autonomy in EPA comments. These topics provide insight into key behaviors that drive different level of resident autonomy and may allow for data-driven revision of EPA entrustment maps.  相似文献   
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