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Purpose

Although mental health problems such as depression after disasters have been reported, positive psychological factors after disasters have not been examined. Recently, the importance of positive affect to our health has been recognised. We therefore investigated the frequency of laughter and its related factors among residents of evacuation zones after the Great East Japan Earthquake of 2011.

Methods

In a cross-sectional study on 52,320 participants aged 20 years and older who were included in the Fukushima Health Management Survey in Japan’s fiscal year 2012, associations of the frequency of laughter with changes in lifestyle after the disaster, such as a changed work situation, the number of family members, and the number of address changes, and other sociodemographic, psychological, and lifestyle factors were examined using logistic regression analysis. The frequency of laughter was assessed using a single-item question: “How often do you laugh out loud?”

Results

The proportion of those who laugh almost every day was 27.1%. Multivariable models adjusted for sociodemographic, psychological, and lifestyle factors demonstrated that an increase in the number of family members and fewer changes of address were significantly associated with a high frequency of laughter. Mental health, regular exercise, and participation in recreational activities were also associated with a high frequency of laughter.

Conclusion

Changes in lifestyle factors after the disaster were associated with the frequency of laughter in the evacuation zone. Future longitudinal studies are needed to examine what factors can increase the frequency of laughter.
  相似文献   
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We investigated the frequency, site, amount, and direction of facial asymmetry in human adults with mandibular prognathism and examined if these characteristics were associated postnatally with cardinal clinical signs that may indicate a predisposition to facial asymmetry. Two hundred twenty young Japanese adults (69 men and 151 women) who exhibited skeletal Class III malocclusions were selected. The sample was divided into a Postnatal Factor Group and a Nonpostnatal Factor Group. The former group included those who had: (1) received orthodontic treatment using a chin cap; (2) exhibited clinical symptoms of temporomandibular joint (TMJ) disorder; (3) reported a history of maxillofacial trauma; or (4) radiographic abnormality of the condyles. Subjects with a deviation of more than 2 mm from the facial midline associated with any of the 4 landmarks (ANS, U1, L1 and Me) were classified as asymmetric and the asymmetry was measured on a postero-anterior (P-A) cephalogram. Radiographic facial asymmetry was found frequently (70%-85%, for Menton), and most obviously in the lower jaw (P < .05). Lateral displacement toward the left side of the face occurred more often than right-sided deviation (P < .001, for Menton). However, the Postnatal Factor Group showed a higher proportion of subjects with lateral deviation toward the right side (P = .0031) and a greater amount (P < .0001) of chin deviation. This was due to the fact that the subjects having TMJ problems as a postnatal factor showed no directional uniqueness in jaw deviation and exhibited a longer distance of deviation.  相似文献   
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OBJECTIVE: To clarify the useful findings for determining whether the submandibular mass is intraglandular or extraglandular. STUDY DESIGN: Forty-eight patients with swelling of the submandibular region were reviewed. The relationship between the lesion and the submandibular gland and the displacement of the anterior facial vein were analyzed. RESULTS: The accuracy of the predictions based on the relationship between the lesion and the submandibular gland (SMG) was 87% on contrast-enhanced CT (CECT), 85% on CT sialography (CTS), and 91% on MRI. Although the displacement of the facial vein outside the lesion suggested an intraglandular lesion, and inside the lesion suggested an extraglandular lesion, these were not sufficient to differentiate the lesions in 7 out of 23 CECT cases and 4 out of 11 MRI cases. CONCLUSION: The finding of a relationship between the lesion and the SMG is the most important finding of this study.  相似文献   
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The purpose of this study was to evaluate the surface roughness and resistance to toothbrush abrasion of three experimental paint-on composite resins developed for the shade modification of crown and bridge resins. The paint-on resins had less filler volume fraction than restorative composites or the crown and bridge resins and consequently were of low viscosity. The maximum surface roughness (Rmax) and the maximum depth loss by abrasion for the paint-on resins following 40,000 cycles of brushing ranged from 2.45 to 4.07 microm and 8.63 to 13.67 microm, respectively. Rmax values were 37.7-67.5% lower than that for the crown and bridge resin subjected to the same test. Wear depth was 19.9-49.4% lower than for the crown and bridge resin. These results suggest that the paint-on resins are expected to have adequate resistance to toothbrush abrasion and may therefore be suitable for clinical use.  相似文献   
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This study showed the influence of the push-back operation on the occurrence of sleep-related apnea in cleft-palate patients with an analysis of arterial oxygen saturation (SpO2) during sleep, polygraphic analysis of nasal air flow, and chest wall movements. The postoperative SpO2 was lower than that of the presurgical period in all cases, requiring from five to nine days to recover to presurgical levels. According to polygraphic analysis this depression of SpO2 was caused by peripheral obstructive apnea, while, in spite of the cessation of nasal airflow, chest wall movement continued.  相似文献   
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So-called Stafne's bone cavity of the mandible were detected by panoramic radiography in 24 patients seen at the Second Department of Oral and Maxillofacial Surgery, Meikai University Hospital, and five associated hospitals. Unilateral and asymptomatic, all lesions were situated near the angle of the mandible, except for the one case that involved the anterior portion of the mandible. The mean age of the patients was 53 years with a range of 31 to 78 years, and included 22 men and 2 women. In this report, radiographic interpretation of the lesion was done, and a radiographic classification was made as follows:
  1. (Indentation type): The inferior border of the mandible is involved.
  2. (Medium type): The lesion is situated above the inferior border of the mandible but below the mandibular canal.
  3. (Deviation type): Deviation of the mandibular canal is suspected.
  4. (Anterior type): The radiolucency is located in the anterior portion of the mandible.
  相似文献   
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OBJECTIVE: To investigate the laterality of the normal asymmetry of the human face, examining differences in laterality in relation to sex, growth stage, and skeletal classification. MATERIALS AND METHODS: A total of 1800 Japanese subjects (651 males and 1149 females; mean age, 15 years 3 months; range, 4 years 2 months to 59 years 11 months) were selected. Individuals in the sample were categorized according to sex, one of three growth stages, and one of three skeletal patterns. Differences in length between distances from the points at which ear rods were inserted to the facial midline and the perpendicular distance from the soft-tissue menton to the facial midline were measured on a frontal facial photograph. Subjects with a discrepancy of more than 3 standard deviations of the measurement error were categorized as having left- or right-sided laterality. RESULTS: Of subjects with facial asymmetry, 79.7% had a wider right hemiface, and 79.3% of those with chin deviation had left-sided laterality. These tendencies were independent of sex, age, or skeletal jaw relationships. In this regard, during pubertal growth, the proportion of subjects with wider right hemiface decreased (P < .0001), whereas the proportion of those with a wider left hemiface increased (P < .01), despite a consistent tendency for right-sided dominance. CONCLUSION: These results suggest that laterality in the normal asymmetry of the face, which is consistently found in humans, is likely to be a hereditary rather than an acquired trait.  相似文献   
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