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Gas station attendants are potentially exposed to carcinogenic substances. This study aimed to evaluate chronic occupational exposed gas station attendant’s according to genetic parameters and its relationship with cancer predisposition. Forty gas station attendants were recruited and paired with 40 control subjects. Thousand cells from each subject were analyzed counting the number of pyknotic (PYC), karyolitic (KYL), karyorrhetic (KHC), condensed chromatin (CC), binucleated (BN), basal cells (BC), Nuclear buds (Nbud), and differentiated cells (DIFF). More 2.000 differentiated cells were analyzed counting micronucleated (MNi) and nuclear buds (NBud). We observed a statistical increase in BC and decrease in DIFF (p < 0.05). PYC, CC, KYL, MN, NBud were statistically increased (p < 0.05). All in all, our data showed elevated DNA damage, chromosomal instability, and cell cycle disturbing in our group of gas station attendants. It is a clear risk for their health in future and could be classified as a cancer predisposition.  相似文献   
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Objective: Describe the use of assistive technology to enhance communication opportunities for older adults.

Methods: A systematic review was conducted in two databases, PubMed and Web of Science, by using two different searches in each. The search was limited to original articles, in English language, including people aged 60 years and older that used any type of assistive technology for communication. The articles found in the initial search were filtered by title, abstracts and the remaining articles were fully read.

Results: Eighteen studies were included in this review after the reading of full-texts. Most of the studies included apparently healthy participants with communication limitations due to aging related changes and the others included people with some pathology that prevent them from normal communication.

Conclusion: Four categories of assistive technology were identified: assistive technology for people with speech problems; robot or videoconferencing systems; Information and Communication Technologies and, other types of assistive technology for communication, such as hearing aids and scrapbooks. Assistive technology for communication of older adults is not only used by people with disabilities that prevent them from usual communication. They are mostly for older adults without a pathological communication problem.  相似文献   

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Diabetes mellitus (DM) leads to a decrease in bone mass and increase the risk of osteoporosis and in this context, many treatments have shown to accelerate bone metabolism. It seems that low-level laser therapy (LLLT) is able of stimulating osteoblast activity and produced increased biomechanical properties. However, its effects on bone in diabetic rats are not fully elucidated. The aim of this study was to evaluate the effects of LLLT on bone formation, immunoexpression of osteogenic factors, biomechanical properties and densitometric parameters in diabetic rats. Thirty male Wistar rats were randomly distributed into three experimental groups: control group, diabetic group, and laser-treated diabetic group. DM was induced by streptozotocin (STZ) and after 1 week laser treatment started. An 830-nm laser was used, performed for 18 sessions, during 6 weeks. At the end of the experiment, animals were euthanized and tibias and femurs were defleshed for analysis. Extensive resorptive areas as a result of osteoclasts activity were noticed in DG when compared to control. Laser-treated animals showed an increased cortical area. The immunohistochemical analysis revealed that LLLT produced an increased RUNX-2 expression compared to other groups. Similar RANK-L immunoexpression was observed for all experimental groups. In addition, laser irradiation produced a statistically increase in fracture force, bone mineral content (BMC) and bone mineral density compared to DG. The results of this study indicate that the STZ model was efficient in inducing DM 1 and producing a decrease in cortical diameter, biomechanical properties and in densitometric variables. In addition, it seems that LLLT stimulated bone metabolism, decreased resorptive areas, increased RUNX-2 expression, cortical area, fracture force, BMD, and BMC. Further studies should be developed to provide additional information concerning the mechanisms of action of laser therapy in diabetic bone in experimental and clinical trials.  相似文献   
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This study aimed to identify risk factors for the incidence of peri‐implant pathology. One‐thousand, two‐hundred and seventy‐fifty patients (255 cases and 1020 controls), rehabilitated with dental implants, were included. Peri‐implant pathology was defined as the presence of peri‐implant pockets ≥ 5 mm, bleeding on probing, vertical bone loss, and loss of attachment ≥2 mm. Cases and controls were matched for age, gender, and duration of follow‐up. A logistic regression model was used, with estimation of the OR for each variable and interaction, with a level of significance of 5%. The risk factors for peri‐implant pathology were: history of periodontitis (OR = 19), bacterial plaque (OR = 3.6), bleeding (OR = 2.9), bone level on the medium third of the implant (OR = 13.9), lack of prosthetic fit or non‐optimal screw joint (OR = 5.9), metal–ceramic restorations (OR = 3.9), and the interaction between bacterial plaque and the proximity of other teeth or implants (PROXI) (OR = 4.3). PROXI (OR = 0.44) exerted a protective effect when independent. Based on the results, peri‐implant pathology represents a group of multifactorial situations with interaction of biological and biomechanical components in its pathogenesis. It was possible to model the condition and to assess, with high precision, the risk profile of each patient.  相似文献   
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This study aimed to evaluate the impact of dental caries treatment on oral health‐related quality of life (OHRQoL) among schoolchildren and the responsiveness of the Child Perceptions Questionnaire (CPQ8‐10) instrument. Brazilian schoolchildren, 8–10 yr of age, were randomly selected and assigned to two groups – dental caries treatment (DCT) and caries‐free (CF) – according to their caries experience [decayed, missing, or filled primary teeth (dmft) and decayed, missing or filled secondary teeth (DMFT) values of ≥0]. The CPQ8‐10 instrument was administered at baseline and at 4 wk of follow‐up (i.e. 4 wk after completion of dental treatment). In the DCT group, increases in CPQ8‐10 scores were observed between the baseline and follow‐up results. However, longitudinal evaluation of the CF group demonstrated no statistically significant difference in CPQ8‐10 scores. Responsiveness of the CPQ8‐10 instrument (magnitude of change in CPQ8‐10 scores) in the DCT group was greater (effect size >0.7) than in the CF group. The findings of this study show that dental caries treatment has an important impact on OHRQoL of children. The CPQ8‐10 was considered an acceptable instrument for longitudinal measurement of changes in OHRQoL.  相似文献   
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