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1.
While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play.  相似文献   
2.
Eleven experiments were conducted on minipigs for the purpose of determining heat distribution in tissue exposed to therapeutic doses of microwaves. Temperatures were measured by means of coated thermocouples from the cutis, subcutis, musculature, and periost. Irradiation was applied to intensities of 10 W, 40 W and 60 W by means of a "Radarmed 12 S 251" circular emitter and to 60 W, 100 W and 140 W, using a trough emitter. Maximum temperature in superficial tissue layers was reached after five to ten minutes of microwave exposure. The temperature rise in the cutis and subcutis was steeper and at a higher rate than that in the muscles. Continuation of microwave irradiation did not cause any further rise in temperature, which was attributed to induction of hyperaemia. No difference regarding heat distribution was found to exist between pulsed and continuous irradiation at equal wattage.  相似文献   
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Mouse peritoneal cells (PC) in culture produce auto-antibodies lyzing bromelain-treated mouse erythrocytes (MRBCbr). These auto-antibodies have been obtained in an homogeneous form in substantial amounts after cell fusion of PC with myeloma X63.Ag8. They have been identified as the anti-Hb-auto-antibodies described by us in 1980. Once coupled to fluorescent microspheres (Ms), they were used to detect the corresponding antigen. It was found that the specific antigen was not only present on the surface of all MRBCbr but also, in a much smaller proportion, on some normal MRBC. Its distribution is not restricted to the mouse: pigeon RBC is stained heavily; human red cells give, more or less, positive reaction, according to their blood group. Some species, as horse RBC, are consistently negative. The opportunity offered by the fluorescent microspheres technique to trace the antigen recognized by the Hb-auto-antibody in the mouse tissues and on cells from other species should lead to a better understanding of the cross-antigenicity of many RBC and of the peculiar auto-immune process involving MRBCbr in the mouse.  相似文献   
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Insomnia is the most frequent sleep disorder and a public health concern that increased during the Covid 19 pandemic. Fully restrictive lockdowns during Covid are interesting periods to examine the impact of environmental and behavioural changes on the emergence of insomnia symptoms. In this cross-sectional study we aimed to (1) determine the main factors associated with insomnia symptoms during a Covid-19 fully restrictive lockdown examining the associated daily life alterations and (2) create a predictive model of insomnia symptoms. We used the data drawn from the “Covid-RythmE” study that reached volunteers from the general French population through an online survey during the last 2 weeks of the 2 month full lockdown. Associations with insomnia symptoms were tested and significant associations were entered in a Backward Stepwise Logistic Regression (BSLR) to assess the best combination to classify individuals with or without insomnia symptoms. From the 1624 participants, 50.64% suffered from mild to severe insomnia symptoms as assessed by the ISI. The best combination for explaining insomnia symptoms with 74.26% of accuracy included: age (OR = 1.15), females (OR = 1.26), smaller home sizes (OR = 0.77), environmental noises (OR = 1.59), anxiety symptoms (OR = 1.24), depressive symptoms (OR = 1.15), regularity of sleep–wake schedules (OR = 1.25), exposure to screen during the morning (OR = 1.13), and LED light during the evening (OR = 1.17). Thus, lifestyle schedule and exposure to natural synchronizers such as light, are primordial in considering in insomnia physiopathology, prevention and treatment, as well as the associated mental health status.  相似文献   
7.
A 75-year-old woman with melena was found to have a carcinoid tumor in the posterior wall of the duodenal bulb. The biology was normal. The tumor measured 10 mm in size, and endoscopic ultrasonography showed only submucosal involvement. There was no liver metastasis and no regional lymph nodes. Tumoral resection was performed laparoscopically with success. Postoperative course was uneventful. Laparoscopic resection could be an appropriate minimally invasive treatment for selected small size duodenal tumors.  相似文献   
8.
The first EORTC (European Organization of Research and Treatment of Cancer) acute myeloblastic leukemia (AML) pilot study (58872) was conducted between January 1988 and December 1991. Out of 108 patients, 78% achieved complete remission (CR), and event-free survival (EFS) and survival rates (s.e., %) at 7 years were 40 (5) and 51% (6%), respectively. It indicated that mitoxantrone could be substituted for conventional anthracyclines in the treatment of childhood AML without inducing cardiotoxicity. The aim of the next EORTC 58921 trial was to compare the efficacy and toxicity of idarubicin vs mitoxantrone in initial chemotherapy courses, further therapy consisting of allogeneic bone marrow transplantation (alloBMT) in patients with an HLA-compatible sibling donor or chemotherapy in patients without a donor. Out of 177 patients, recruited between October 1992 and December 2002, 81% reached CR. Overall 7-year EFS and survival rates were 49 (4) and 62% (4%), respectively. Out of 145 patients who received the first intensification, 39 had a sibling donor. In patients with or without a donor, the 7-year disease-free survival (DFS) rate was 63 (8) and 57% (5%) and the 7-year survival rate was 78 (7) and 65% (5%), respectively. Patients with favorable, intermediate and unfavorable cytogenetic features had a 5-year EFS rate of 57, 45 and 45% and a 5-year survival rate of 89, 67 and 53%, respectively.  相似文献   
9.
Elevated office blood pressure (BP) has previously been associated with increased levels of circulating extracellular vesicles (EVs). The present study aimed to assess the relationship between levels of platelet derived EVs, ambulatory BP parameters, and pulse wave velocity as a marker of macrovascular organ damage. A total of 96 participants were included in the study. Platelet‐derived extracellular vesicles (pEVs) were evaluated by flow cytometry (CD41+/Annexin v+). BP evaluation included unobserved automated office BP and ambulatory BP monitoring. Carotid‐femoral pulse wave velocity (PWV) was measured as a marker of macrovascular damage. pEVs correlated with nocturnal systolic BP (r = 0.31; p = .003) and nocturnal dipping (r = ‐0.29; p = .01) in univariable analysis. Multivariable regression models confirmed robustness of the association of EVs and nocturnal blood pressure (p = .02). In contrast, systolic office, 24h‐ and daytime‐BP did not show significant associations with pEVs. No correlations were found with diastolic BP. Circulating pEVs correlated with pulse wave velocity (r = 0.25; p = .02). When comparing different hypertensive phenotypes, higher levels of EVs and PWV were evident in patients with sustained hypertension compared to patients with white coat HTN and healthy persons. Circulating platelet derived EVs were associated with nocturnal BP, dipping, and PWV. Given that average nocturnal BP is the strongest predictor of CV events, platelet derived EVs may serve as an integrative marker of vascular health, a proposition that requires testing in prospective clinical trials.  相似文献   
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