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101.
Christina Erbe Dr/HR Sandra Hornikel Irene Schmidtmann Heiner Wehrbein 《Journal of orofacial orthopedics》2011,72(1):13-20
Objective
The placement of orthodontic bands usually increases plaque accumulation due to numerous mechanical retention sites. The purpose of this investigation was to evaluate the amount and distribution pattern of biofilm in the oral (palatal and lingual) and interproximal regions surrounding orthodontic bands.Materials and Methods
We evaluated the formation of biofilm on 32 orthodontic bands which had been placed intraorally for 6?C37?months. Two parameters were measured: the percentage of surface covered by biofilm (quantity) and the biofilm distribution pattern of accumulation. We measured these two parameters in four regions of interest: the mesial and distal interproximal regions, as well as the mesial and distal regions of the oral attachment.Results
The quantity of biofilm formation was similar in all four regions of interest, ranging from 13.3% to 16.8%. In contrast to biofilm quantity, distribution patterns differed in the four regions. In the mesial and distal interproximal regions it appeared as extensive insular areas in 87.5% and 71.9%, respectively, whereas it appeared more often supragingival and linear in nature in regions adjacent to the oral attachment, i.e. in 65.6% and 68.8%, respectively.Conclusion
Our results indicate that firstly, oral hygiene in the palatal and lingual regions of orthodontic bands seems as difficult as it is in the interproximal areas, thus requiring thorough hygiene in both areas. Secondly, orthodontic patients with a history of periodontal disease require special attention regarding the use of orthodontic bands. 相似文献102.
Sex hormones play a key role in bone homeostasis, and oral contraceptive (OC) use may affect bone mass in women. However,
the nature of the association between OC use and bone remains controversial. This paper critically reviews studies on OC use
and bone published between January 2009 and August 2010. Studies of OC use and bone mass mainly focus on adolescents or young
adults and showed mixed results. Weak evidence suggests that OC use has no effect or a beneficial effect on bone mass, except
in women commencing OCs shortly after menarche, and a consistently negative effect on bone turnover markers. A limited number
of studies have examined the effect of ultra-low-dose OC (20 μg ethinyl estradiol) on bone mass in adolescents or young adults,
and present conflicting results. The lack of randomized trials indicates that further high-quality prospective studies are
required to investigate the effect of OC use on bone mass, particularly the optimal dose and timing of initiation of OC use
in adolescents requiring contraception. 相似文献
103.
A. A. Venn E. Tambutté S. Lotto D. Zoccola D. Allemand S. Tambutté 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(39):16574-16579
The challenges corals and symbiotic cnidarians face from global environmental change brings new urgency to understanding fundamental elements of their physiology. Intracellular pH (pHi) influences almost all aspects of cellular physiology but has never been described in anthozoans or symbiotic cnidarians, despite its pivotal role in carbon concentration for photosynthesis and calcification. Using confocal microscopy and the pH sensitive probe carboxy SNARF-1, we mapped pHi in short-term light and dark-incubated cells of the reef coral Stylophora pistillata and the symbiotic anemone Anemonia viridis. In all cells isolated from both species, pHi was markedly lower than the surrounding seawater pH of 8.1. In cells that contained symbiotic algae, mean values of pHi were significantly higher in light treated cells than dark treated cells (7.41 ± 0.22 versus 7.13 ± 0.24 for S. pistillata; and 7.29 ± 0.15 versus 7.01 ± 0.27 for A. viridis). In contrast, there was no significant difference in pHi in light and dark treated cells without algal symbionts. Close inspection of the interface between host cytoplasm and algal symbionts revealed a distinct area of lower pH adjacent to the symbionts in both light and dark treated cells, possibly associated with the symbiosome membrane complex. These findings are significant developments for the elucidation of models of inorganic carbon transport for photosynthesis and calcification and also provide a cell imaging procedure for future investigations into how pHi and other fundamental intracellular parameters in corals respond to changes in the external environment such as reductions in seawater pH. 相似文献
104.
Magnussen CG Fryer J Venn A Laakkonen M Raitakari OT 《Ultrasound in medicine & biology》2006,32(9):1323-1329
Flow-mediated dilation (FMD) and common carotid intima-media thickness (CIMT) are intermediate endpoints for cardiovascular disease. The purpose of this study was to determine whether a portable ultrasound machine was capable of valid measurements of FMD and CIMT compared with a clinic-based machine under similar conditions. Vascular images were taken on 23 apparently healthy young adults with the portable type and clinic type instruments. The analyses revealed a high level of agreement between the two machines for measurements of mean [corrected] CIMT (mean difference [MD] = -0.025 mm, limits of agreement [LOA] = -0.080, 0.029 mm), maximum [corrected] CIMT (MD = 0.001 mm, LOA = -0.065, 0.065 mm) and FMD measures of brachial diameter (baseline MD = 0.199 mm, LOA = -0.210, 0.608 mm, maximum MD = 0.218 mm, LOA = -0.162, 0.597 mm). Reasonable agreement was found for %FMD measurements (MD = 0.27%, LOA = -4.91, 5.44%). The within-machine coefficient of variation results for mean [corrected] CIMT (5.0%), maximum [corrected] CIMT (4.3%), baseline (6.3%) and maximum (5.4%) brachial diameter and %FMD (30.1%) were comparable with normal within-subject variation. We conclude that the portable ultrasound machine can provide measurements of FMD and CIMT that are highly comparable with measurements obtained from a clinic-based machine under similar clinical conditions. 相似文献
105.
106.
107.
Pelvic fracture injuries of the female urethra 总被引:3,自引:0,他引:3
OBJECTIVE: To review pelvic fracture urethral injuries in women, generally regarded as rare and thus discussed infrequently. PATIENTS AND METHODS: Twelve patients (age range 7-51 years) with such injuries were reviewed; most had associated injuries, generally more severe than seen in males with urethral injuries. RESULTS: Patients with milder injuries, perhaps damaging just the innervation of the urethra, presented with incontinence; more severe injuries seemed to cause a longitudinal tear in the urethra but again patients presented mainly with incontinence problems. The most severe injuries were associated with complete rupture of the urethra and a distraction defect suggesting an avulsion injury. These problems were difficult to treat both reconstructively and in providing continence. CONCLUSIONS: Pelvic fracture urethral injuries occur in females, but less often than in males. The female urethra seems relatively resistant to injury; differing degrees of severity of pelvic trauma cause different types of urethral injury but in general, a more severe injury is needed to damage it than is necessary in males. 相似文献
108.
109.
Skipping breakfast among Australian children and adolescents; findings from the 2011–12 National Nutrition and Physical Activity Survey
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Kylie J. Smith Monique C. Breslin Sarah A. McNaughton Seana L. Gall Leigh Blizzard Alison J. Venn 《Australian and New Zealand journal of public health》2017,41(6):572-578
Objective : Skipping breakfast has been linked with poor diet quality, higher BMI and adverse cardiometabolic outcomes. This study aimed to determine the prevalence and correlates of skipping breakfast among Australian children and adolescents. Methods : A total of 1,592 2–17‐year‐olds completed two 24‐hour recalls, collected via face‐to‐face and telephone interview, in the 2011–12 National Nutrition and Physical Activity Survey. Breakfast was an eating occasion of ≥210kJ named as ‘breakfast’ by the participant. Child, household and adult correlates of skipping breakfast were reported. Odds ratios were calculated using ordinal regression. Linear regression was used to examine differences in dietary intake. Survey weights were applied to give nationally representative estimates. Results : Most (86.8% of boys, 81.4% of girls) ate breakfast on both days, 11.8% of boys and 14.8% girls skipped on one day and 1.4% boys and 3.8% girls skipped on both days. Characteristics associated with skipping breakfast were being female, being older, being underweight or overweight/obese, poorer diet, lower physical activity, inadequate sleep, lower household income, greater socioeconomic disadvantage, and being from a single‐parent home. Conclusion : Skipping breakfast was common among Australian adolescents but few consistently skipped. Implications for public health : Interventions to increase breakfast should target adolescents, particularly girls, and low SEP households. 相似文献
110.
Eruptive syringoma is a very rare variant of syringoma. It is a benign adnexal tumor of the intraepidermal portion of eccrine sweat ducts. Here we report a 32-year-old female presented with classical asymptomatic eruptive syringomas involving her face and extremities. 相似文献