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《Pediatric Dental Journal》2019,29(3):116-122
ObjectiveInvestigation of dynamic occlusal contacts when food particles are being pulverized during chewing is of interest for many researchers and clinicians. However, measurement of dynamic occlusal contacts during chewing is difficult, and differences between children and adults have not been established. The purpose of this study is to test the hypothesis that dynamic occlusal contacts of children differ from those of adult females.Subjectsand methods: Thirteen healthy children (4–6 years of age; mean age 5 years, 7 months) and thirteen adult females (18–26 years of age; mean age 20 years, 7 months) with normal occlusion participated in this study. Occlusal contact area (OCA) was estimated with a developed measurement system combining 3-D digitization of tooth shape with 3-D tracking of mandibular movements (1) during the closing stroke, (2) at the maximum closing position (MCP), and (3) during the opening stroke. OCA at static maximum intercuspation (ICP) was also estimated.ResultsAt the MCP, the children's OCA was less than 76.4% of the contact area seen at the ICP. The timing of maximum OCA in children was shifted more towards the opening stroke compared with adults, and the OCA remained greater during opening in children than adults. The occurrence of the MCP was less stable in children than in adults, both between subjects and within subjects.ConclusionsWe conclude that both the amount of OCA and the pattern of occlusal contacts during the occlusal phase of chewing completely differ between children and adult females. 相似文献
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We describe two cases of acute‐onset erythema, peeling, and pruritus or tenderness isolated to the palmar surface of the hands. A detailed exposure history revealed significant periods of contact with homemade slime; given the clinical findings and timing of exposure, acute contact dermatitis of the hands was suspected. Symptoms and clinical findings resolved after avoidance of the suspected causative contactants. There are few if any reported cases of contact dermatitis to homemade slime in the literature; this serves to highlight the importance of a thorough exposure history in the evaluation of hand dermatitis. 相似文献
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Platelets have diverse roles in immune processes in addition to their key functions in haemostasis and thrombosis. Some studies imply that platelets may be possibly related to the immune tolerance induction. However, the role of platelets in the development of immune tolerance is not fully understood. The purpose of this study was to investigate the role of platelets in the development of regulatory mechanisms responsible for cutaneous inflammation using a mouse model of low zone tolerance (LZT). Mice were treated with 2,4,6‐trinitro‐1‐chlorobenzene (TNCB) 8 times every other day for tolerance induction with administration of anti‐platelet antibody or control antibody during the tolerance induction phase every 3 days. After the treatment for the tolerance induction, mice were sensitized and then challenged with TNCB. The contact hypersensitivity (CHS) was significantly decreased at 24 hours after challenge in the mice with LZT than in those without LZT. Platelet depletion via administration of anti‐platelet antibody reversed the inhibition of CHS and reduced the frequency of Foxp3+ Tregs in the inflamed skin and draining lymph nodes in mice with LZT. In addition, repeated low‐dose skin exposure resulted in elevated plasma levels of transforming growth factor (TGF)‐β1. Interestingly, platelet depletion reduced plasma TGF‐β1 levels of mice with LZT. Furthermore, the CHS response was reduced by administration of recombinant TGF‐β1 during platelet depletion in mice with LZT. Administration of anti‐TGF‐β antibody reversed the inhibition of the CHS responses. These results suggest that platelets are involved in the induction of immune tolerance via the release of TGF‐β1. 相似文献
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Hyperosmotic tear stimulates human corneal nerve endings, activates ocular immune response, and elicits dry-eye symptoms. A soft contact lens (SCL) covers the cornea preventing it from experiencing direct tear evaporation and the resulting blink-periodic salinity increases. For the cornea to experience hyperosmolarity due to tear evaporation, salt must transport across the SCL to the post-lens tear film (PoLTF) bathing the cornea. Consequently, limited salt transport across a SCL potentially protects the ocular surface from hyperosmotic tear. In addition, despite lens-wear discomfort sharing common sensations to dry eye, no correlation is available between measured tear hyperosmolarity and SCL-wear discomfort. Lack of documentation is likely because clinical measurements of tear osmolarity during lens wear do not interrogate the tear osmolarity of the PoLTF that actually overlays the cornea. Rather, tear osmolarity is clinically measured in the tear meniscus. For the first time, we mathematically quantify tear osmolarity in the PoLTF and show that it differs significantly from the clinically measured tear-meniscus osmolarity. We show further that aqueous-deficient dry eye and evaporative dry eye both exacerbate the hyperosmolarity of the PoLTF. Nevertheless, depending on lens salt-transport properties (i.e., diffusivity, partition coefficient, and thickness), a SCL can indeed protect against corneal hyperosmolarity by reducing PoLTF salinity to below that of the ocular surface during no-lens wear. Importantly, PoLTF osmolarity for dry-eye patients can be reduced to that of normal eyes with no-lens wear provided that the lens exhibits a low lens-salt diffusivity. Infrequent blinking increases PoLTF osmolarity consistent with lens-wear discomfort. Judicious design of SCL material salt-transport properties can ameliorate corneal hyperosmolarity. Our results confirm the importance of PoLTF osmolarity during SCL wear and indicate a possible relation between PoLTF osmolarity and contact-lens discomfort. 相似文献
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目的:系统评价首发精神障碍家庭照顾者的经历,为患者早期康复及照顾者心理健康问题的干预提供循证依据。方法:计算机检索The Cochrane Library、Ovid 、PubMed、Embase、Web of Science、CBM、CNKI、VIP和WANFANG DATE 数据库,检索时限均从建库至2021年7月31日,使用“JBI循证卫生保健中心质性研究质量评价标准”评价符合纳入标准的文献,并采用汇集性整合法对研究结果进行整合。结果:纳入12篇文献,提炼出60个研究结果,整理成8个类别,得出3个整合结果。分别是多维度的挑战、成长或缺如的角色结局、急需的社会支持。结论:亟需提高全民心理健康素质及去精神障碍疾病污名化,营造患者及家属无障碍化就医环境;关注家庭照顾者早期心理健康的干预,满足其社会支持的需要,提高该类人群应激应对能力,促进照顾者心理康复。 相似文献
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《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials. 相似文献
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Given that first responders experience elevated rates of posttraumatic stress disorder and suicide, there is a need for evidence-based assessments and treatments to accurately assess, diagnose, and evaluate treatment outcome. This study examined the psychometric properties of the Posttraumatic Stress Disorder (PTSD) Checklist for DSM-5 (PCL-5) in a sample of 133 firefighters/emergency medical technicians and police officers seeking treatment for PTSD. The results indicated that PCL-5 scores showed strong internal consistency and convergent and discriminant validity. Signal detection analyses indicated a good diagnostic accuracy and an optimal cutoff score of 41 for detecting PTSD. Consistent with recent studies, confirmatory factor analyses indicated that the anhedonia model of PTSD best fit the data. Overall, findings support use of the PCL-5 as a psychometrically sound measure of PTSD in individuals at high risk for exposure to trauma. 相似文献