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In play, children often explore mathematical ideas that are vital for future learning. Children’s play also reveals gender differences in both colour and toy preferences. The authors examined how gender-related colour preferences of 5-year-olds are related to preferences for math-specific games/toys and gendered beliefs about math. Spanish preschoolers (N?=?143) completed a self-report measure of gendered beliefs about math. Children then indicated their favourite colour and were given five math-specific games/toys in that colour. Play times for each game/toy were recorded. Three findings emerged. First, girls preferred games/toys of particular colours (pink/purple) that differed from boys’ preferences (blue/red). Second, play time with math games/toys did not differ between girls and boys. Third, 5-year-olds of both genders thought that girls liked math more than boys did. This is the youngest age at which these gendered beliefs about math have been shown, and suggests new theorizing about stereotypes, gender, and math.  相似文献   
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Epithelioid cells with foamy cytoplasm (histiocytoid features) are typical histopathologic findings among benign and malignant histiocytic neoplasms such as xanthoma and atypical fibroxanthoma. However, these changes are unusual in melanoma, which is typically composed of nested and variably pigmented atypical epithelioid cells. Here, we report a patient with metastatic melanoma in lymph nodes presenting with prominent balloon cell/histiocytoid features expressing melanocytic markers, after treatment with nivolumab. This report suggests that the spectrum of neoplasms with histiocytoid features should be expanded to include melanoma, a pattern that, to the best of our knowledge, is uncommon, especially in the setting of post‐neoadjuvant therapy.  相似文献   
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Understanding the factors that determine the type and amount of formal care is important for predicting use in the future and developing long-term policy. In this context, we jointly analyze the provision of care at both the extensive (choice of care) and the intensive margin (number of hours of care received). In particular, we estimate and test, for the first time in this area of research, a sample selection model with the particularities that the first step is a multinomial logit model and the hours of care is an interval variable. Our results support the complementary and task-specific models which evidence has been found in other countries. Furthermore, we obtain evidence of substitution between formal and informal care for the male, young, married and unmarried subsamples. Regarding the hours of care, we find significant biases in predicted hours of care when sample selection is not taken into account. For the whole sample, the average bias is 2.77% for total hours and 3.23% for formal care hours. However, biases can be much larger (up to 10–15%), depending on the subsample and the type of care considered.  相似文献   
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Abstract

effect of acidic fibroblast growth factor (aFCF) was investigated on junctional communication of rat Schwann cells (SC) in culture. As measured by dye transfer, the incidence of coupling between SC was very low during the phase of proliferation and increased slowly and progressively with time under culture conditions that induced the myelinating phenotype. Treatment with aFCF alone or in combination with heparin decreased markedly coupling between SC in both culture stages. The coupling inhibition was rapid, the earliest effects being apparent 5-15 min after addition of grdwth factor, and was transient with a slower recovery of coupling at 1-3 h. The uncoupling effect of aFCF could be prevented by an inhibitor of protein-tyrosine kinase. Addition of heparin to cultures decreased the most effective aFCF concentration by 100-fold, from 100 ng ml-1 to 1 ng ml-1 The dose-response curves exhibited a characteristic windowshape. The results suggest that FGF might be involved in the regulation of the junctional communication between rat SC via tyrosine kinases. [Neurol Res 2000; 22: 685-691]  相似文献   
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ObjectiveTo find out the opinions of health professionals on adolescent alcohol drinking and their evaluation of the existing legal regulation measures.MethodologyDesign: Qualitative and exploratory study, based on semi-structured interviews.Setting: Four cities representing four different regions in Spain: Palma de Mallorca, Granada, Barcelona and Pamplona.Participants: A total of 36 physicians and nurses from four Spanish regions, working in Primary Care and Emergency Care, selected by intentiones samples.Measurements: A total of 36 deep interviews, analysed using the software Nudist Vivo 4.0.ResultsHealth professionals accept their important role in preventing and intervening in adolescent alcohol drinking. Generally, they consider it as a public health problem. Prevention is associated with Primary Care, while the Emergency Departments act in specific situations of alohol abuse. Adolescents infrequently visit Primary Care, thus prevention must centre on education system and constant coordination between health professional and parents. Health personnel do not have sufficient knowledge on legal regulations. They consider educational measures as more efficient than sanctions.ConclusionsSpecific professional training is required in order to guarantee the coordination between the health and education systems and the family.  相似文献   
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