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Effects of supervised daily dental plaque removal by children after 3 years   总被引:1,自引:0,他引:1  
The benefits of a school-based plaque removal program are presented. Children in grades 5-8 were included in a study which was designed to determine the effect on oral hygiene, gingival inflammation and dental caries of removing dental plaque through supervised daily flossing and toothbrushing in school. A fluoride-free dentifrice was used. Controls did not receive instruction in plaque removal procedures nor did they engage in plaque removal activities at school. For three school years the students in the treatment group practiced daily plaque removal, supervised by trained personnel. All participants were examined initially for plaque (PHP), gingival inflammation (DHC) and dental caries (DMFS). Girls in the treatment group showed a significant reduction (28%) in mean plaque scores and, for girls and boys, the mean changes in gingivitis scores were significantly reduced (40% and 17%, respectively). Adjusted mean incremental DMF surface scores were 13 % lower in the treatment group than in the control group. The difference between groups was not statistically significant and was accounted for entirely by the findings in mesial and distal surfaces (26%). This difference approached statistical significance (P= 0.07).  相似文献   
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Sj?gren's syndrome is a common autoimmune rheumatic disease. The most common symptoms of Sj?gren's syndrome are extreme tiredness, along with dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia). Saliva plays an essential role in numerous functions of the mouth. Xerostomia can be caused by medications, chronic diseases like Sj?gren's syndrome, and medical treatments, such as radiation therapy and bone marrow transplant. Xerostomia can eventually lead to difficulty in swallowing, severe and progressive tooth decay, or oral infections. Despite having excellent oral hygiene, individuals with Sj?gren's syndrome have elevated levels of dental caries, along with the loss of many teeth, early in the disease. Sj?gren's syndrome alters the protein profile and brings about a change in the composition of saliva. There is an increase in the levels of lactoferrin, beta(2)-microglobulin, sodium, lysozyme C, and cystatin C, and a decrease in salivary amylase and carbonic anhydrase. Up to 90% of individuals with Sj?gren's syndrome have antibodies targeting the Ro 60 and La autoantigens. Natural aging, regardless of Sj?gren's syndrome, is also another factor that brings about a significant change in the composition of saliva. The most prevailing cause of xerostomia in elderly persons is the use of anticholinergic medications. Currently, there is no cure for Sj?gren's syndrome, and treatment is mainly palliative.  相似文献   
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W F Voyles  D C Fisher  E C Mathews 《Postgraduate medicine》1985,78(6):151-5, 158, 161-4
Ultrasound is of proven clinical utility for imaging cardiac structures. Doppler ultrasonic techniques can be used with or without echocardiography for noninvasive hemodynamic studies. The usefulness of Doppler ultrasonic techniques in the noninvasive laboratory has been shown recently at the Massachusetts General Hospital, Boston. In 61 of 100 consecutive patients in a prospective study, Doppler ultrasound provided clinical information that could not be obtained with echocardiographic studies alone. The advantages of this technique for noninvasive cardiac studies are now being recognized in the general medical community. The results of ongoing clinical investigations will help define the role of Doppler echocardiography as a clinically useful diagnostic tool for cardiac evaluation.  相似文献   
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Tourette syndrome (TS) is a neurodevelopmental disorder with a complex genetic etiology. Through an international collaboration, we genotyped 42 single nucleotide polymorphisms (p < 10−3) from the recent TS genomewide association study (GWAS) in 609 independent cases and 610 ancestry‐matched controls. Only rs2060546 on chromosome 12q22 (p = 3.3 × 10−4) remained significant after Bonferroni correction. Meta‐analysis with the original GWAS yielded the strongest association to date (p = 5.8 × 10−7). Although its functional significance is unclear, rs2060546 lies closest to NTN4, an axon guidance molecule expressed in developing striatum. Risk score analysis significantly predicted case–control status (p = 0.042), suggesting that many of these variants are true TS risk alleles. Ann Neurol 2014;76:310–315  相似文献   
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Fenobam is a negative allosteric modulator of the metabotropic glutamate receptor subtype 5 (mGluR5) with inverse agonist activity and is expected to contribute to the treatment of neuropsychiatric disorders involving dysfunction of mGluR5 including Fragile X syndrome. This study examined whether [11C]ABP688, an antagonist PET radioligand, competes with fenobam for the same binding site in the nonhuman primate brain and would allow examination of occupancy‐plasma concentration relationships in the evaluation of the drug for target disorders in the human brain. Four paired PET studies with [11C]ABP688 were performed in baboons at a baseline condition and after intravenous treatment with fenobam at different dose levels (0.3–1.33 mg/kg). Total distribution volume (VT) and binding potential (BPND) using the cerebellum as a reference region were obtained by the plasma reference graphical method. Then it was examined whether occupancy follows a dose‐dependent, saturating pattern that was predicted by a modified first‐order Hill equation in individual regions. Baseline regional VT and BPND values agreed with previously published data. Occupancy showed dose‐dependent and saturating patterns in individual regions, reaching >90% occupancy at 1.33 mg/kg dose of fenobam in the majority of regions. To our knowledge, this is the first use of PET to characterize the mGluR5 therapeutic drug fenobam. This study demonstrates a proof of principle for determining the in vivo occupancy of fenobam in primates. The results indicate that [11C]ABP688 and PET may be useful for examination of occupancy of mGluR5 by fenobam, which should prove to be useful for designing future studies and treatment of human disease states. Synapse 68:565–573, 2014 . © 2014 Wiley Periodicals, Inc.  相似文献   
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