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Fredrik Petersson Desai Vijayadwaja Kwok Seng Loh Kong-Bing Tan 《Head and neck pathology》2014,8(3):364-368
We present a case of non-keratinizing carcinoma of the nasopharynx (NK-NPC) with an unusual histopathological pattern. The neoplastic cells were arranged in anastomosing cords embedded in a stroma which contained a significant component of alcian blue-positive myxoid substance forming a reticular pattern. These histopathological features gave an initial impression of a salivary gland-type carcinoma. On immunohistochemistry the tumor cells were strongly and diffusely positive for cytokeratins (AE1-3 and 5/6) and p63 and there was strong and diffuse nuclear positivity for Epstein–Barr virus-encoded small RNA on in situ hybridization. This case highlights the histomorphological variability of NK-NPC. Awareness of the histological spectrum of NK-NPC is important in clinical practice and this is not always adequately highlighted in currently used standard textbooks of Head and Neck Pathology. 相似文献
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《Dental materials》2019,35(8):1065-1072
Materials used to seal the endodontic space are subjected to enzymatic degradative activities of body fluids and bacteria.ObjectivesTo assess effects of simulated human salivary, blood and bacterial esterases (SHSE) on physical properties of typical restorative material and root canal sealers.MethodsSpecimens of set methacrylate-based resin composite (BisfilTM2B; RC), calcium-silicate sealer (EndoSequence®; BC) or epoxy-resin sealer (AH-Plus®; ER) were tested after up to 28 Days exposure to phosphate buffered saline (PBS) or SHSE, using ANSI/ADA-57:2000 and ISO-6876:2012.ResultsRegardless of media, microhardness increased with time for BC remained unchanged for ER and decreased for RC (p < 0.05). SHSE moderated the increase for BC compared to PBS (28.0 ± 4.8 vs. 38.1 ± 7.9 KHN) at 7 Days, and enhanced the decrease for RC at 7 Days (55.6 ± 7.1 vs. 66.3 ± 6.5 KHN) and 28 Days (52.3 ± 9.2 vs. 62.6 ± 8.5 KHN). Compressive strength was enhanced only for BC by either media. BC expanded with time for both incubation conditions; SHSE moderated the expansion compared to PBS at 7 Days (0.026 ± 0.01% vs. 0.049 ± 0.007%). Shrinkage of ER was similar for both incubation media and was lower than that for RC (p < 0.05). Shrinkage of RC was enhanced by SHSE compared to PBS at 7 Days (0.5 ± 0.07% vs. 0.38 ± 0.08%). Weight loss was lowest for ER and highest for BC (p < 0.05). It was enhanced by SHSE compared to PBS for BC at 28 Days (2.40 ± 0.2 vs. 2.96 ± 0.19 W L%), and for RC at 7 Days (0.54 ± 0.09 vs. 0.80 ± 0.1 W L%).SignificanceSimulated body fluids and bacterial esterases affected the physical properties of test materials, suggesting potential impacts on sealing ability and resistance to bacterial ingress, and tooth strength ultimately affecting their clinical performance. 相似文献
967.
S. Chiodo A. Tessitore C. Cortis G. Cibelli C. Lupo A. Ammendolia M. De Rosas L. Capranica 《Scandinavian journal of medicine & science in sports》2011,21(1):111-119
The aim of this study was to evaluate the effects of an official Taekwondo competition on the heart rate (HR), salivary α‐amylase (sA‐A), salivary free cortisol (sC), and Profile of Mood States (POMS) in 10 young male (14±0 years) and six female (13±1 years) athletes. POMS and hormones were measured 15 min before and directly after the competition. During the recovery phase (30 and 90 min), sA‐A and sC were also measured. HR measured during the competition was expressed as a percentage of individual's maximal heart rate (%HRmax) to evaluate the intensity of exercise. During the competition, athletes spent 65% of the time working at HR>90% of individuals HRmax. A significant increase (P<0.0001) in sA‐A (115%) was observed at the end of the match. At 30 min of recovery, sA‐A returned to the pre‐competition level. The peak sC values were observed at 30 min of recovery (P<0.001), returning to the pre‐competition level at 90 min of recovery. A gender difference (P=0.01) emerged only for sC, although a similar trend was observed for female and male athletes. Significantly higher post‐match scores emerged for Anger‐hostility (pre: 6.1±1.1, post: 11.2±1.9; P=0.03) and Depression‐dejection (pre: 4.5±0.5, post: 10.2±1.9; P=0.006), whereas the reverse picture was observed for Vigour‐activity (pre: 23.2±1.2, post: 16.3±1.7; P=0.0006). Taekwondo competition results in temporary changes in the stress‐related parameters measured in this study. The present findings suggest that this experimental paradigm can represent a useful model for further research on the effects of various stressors (i.e., training and competition) in Taekwondo athletes of different levels (i.e., novice, international). 相似文献
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Alessandra BERRY Marta BORGI Livia TERRANOVA Flavia CHIAROTTI Enrico ALLEVA Francesca CIRULLI 《Psychogeriatrics》2012,12(3):143-150
Aim: An ever increasing interest in the therapeutic aspects of the human‐animal bond has led to a proliferation of animal‐assisted interventions (AAI) involving dogs. However, most of these programs lack a solid methodological structure, and basic evaluative research is needed. The purpose of this study was to test the value of dog‐assisted interventions as an innovative tool to increase quality of life in the geriatric population. Methods: Nineteen patients (men and women) with a mean age of 85 years participated in the study. Interactions between patients and visiting dogs occurred either in a social situation (socialization sessions) or in a therapeutic context (physical therapy sessions). We derived and characterized a specific ethogram of elderly‐dog interactions aimed at evaluating the effectiveness of visiting dogs in improving mood, catalyzing social interactions and reducing their everyday apathetic state. Cortisol levels were also measured in the saliva, and depressive state was evaluated. Results: Overall, results show a time‐dependent increase in social behaviour and spontaneous interactions with the dogs. Dog‐mediated interactions affected the daily increase in cortisol levels, thus having an ‘activational effect’, in contrast to the apathetic state of institutionalized elderly. Conclusions: Dog‐mediated intervention programs appear to be promising tools to improve the social skills and enrich the daily activities of the institutionalized elderly. 相似文献
970.
Andrew T. Gloster Jens Klotsche Tatiana Aggeler Noemi Geisser Gregory Juillerat Nicole Schmidlin 《Psychotherapy research》2019,29(4):503-513
Background and Objectives: Acceptance and Commitment Therapy (ACT), a behavioral therapy that targets psychological flexibility (PF), has been shown to be efficacious across a wide range of problems, including chronic work-related stress and perceived stress. ACT’s effect on the multiple levels of the acute stress response (i.e., subjective and biological) is less well understood. The aim of the current study was to test whether ACT, by working toward PF, would reduce both the endocrine and subjective evaluations of participants’ acute stress response. Methods: Participants (n?=?35) were randomized to an ACT condition or waitlist (WL). Participants in the ACT condition received a two-day ACT workshop on how to flexibly deal with stress. All participants completed a standardized laboratory stress test. Results: The ACT and WL groups did not differ on main comparisons of the endocrine response (i.e., cortisol) or subjective evaluation. Baseline levels of PF moderated some outcomes. Avoidant participants had a stronger endocrine stress reaction if they received the ACT intervention. Limitations: The control condition was a WL and not an active intervention comparison. Conclusions: ACT is not useful in reducing the acute stress response and may even be iatrogenic, at least during tasks with little real-world impact for their personal values.
Clinical or methodological significance of this article:
This was one of the first studies to investigate the impact of an ACT intervention on biological parameters.
The short-term intervention did not attenuate acute endocrine stress levels or subjective stress appraisals.
Future studies should investigate which interventions and under which conditions attenuate acute and long-term stress responses.