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11.
Gracia-Marco L Tomas C Vicente-Rodriguez G Jimenez-Pavon D Rey-Lopez JP Ortega FB Lanza-Saiz R Moreno LA 《Journal of sports sciences》2010,28(13):1383-1389
The aims of this study were to identify differences between the sexes in extra-curricular participation in sports and to determine its association with body fat and socio-demographic factors in Spanish adolescents. A total of 2165 adolescents (1124 males and 1041 females) aged 13.0-18.5 years from the AVENA Study participated. Participants filled in an ad hoc questionnaire for extra-curricular participation in sports, which was the dependent variable. Independent variables were: age, percent body fat, and father's and mother's educational level and occupation. Chi-square tests and logistic regression were applied. Bivariate analysis showed for male adolescents that age and father's occupation were related to extra-curricular participation in sports. In addition, body fat and mother's education and occupation (all P?0.05) were related to extra-curricular participation of in sports for female adolescents. Logistic regression analysis showed that the likelihood of involvement in extra-curricular participation in sports was 5.3-fold (3.86-7.38) higher for males than females. Age and father's education in both males and females were independently associated with extra-curricular participation in sports. In summary, Spanish male adolescents were shown to engage in more extra-curricular sports than females. In addition, age and father's education (in both sexes) were associated with the participation of their offspring in extra-curricular sports during adolescence. 相似文献
12.
Cadore E Lhullier F Brentano M Silva E Ambrosini M Spinelli R Silva R Kruel L 《Journal of sports sciences》2008,26(10):1067-1072
The aim of present study was to examine the relationships between serum and salivary values of free testosterone, dehydroepiandrosterone, and cortisol before and after a session of resistance exercise. Twenty-eight healthy men (mean age 40 years, s = 4) participated in the present study. Serum and salivary samples were collected at rest and after a multiple-sets resistance exercise protocol, of approximately 25 minutes duration. Concentrations of free testosterone, dehydroepiandrosterone, and cortisol were measured using radioimmunoassay kits. No significant correlation was observed between serum free testosterone and salivary testosterone (r = 0.22 to 0.26, P > 0.05). Serum cortisol was significantly correlated with salivary cortisol before (r = 0.52, P = 0.005) and after (r = 0.62, P = 0.001) the exercise protocol. Serum and salivary concentrations of dehydroepiandrosterone were significantly correlated before (r = 0.68, P < 0.001) and after (r = 0.7, P < 0.001) exercise. The results of the present study suggest that even under exercise conditions, the salivary values of cortisol and dehydroepiandrosterone can reflect the behaviour of these hormones in blood. However, further studies are necessary to verify if salivary testosterone reflects the behaviour of serum free testosterone during resistance exercise. 相似文献
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Ruth Neustifter Markie L.C. Blumer Jessica O'Reilly Francisco Ramirez 《Sex education》2015,15(5):540-552
The literature on the impact of entertainment media on sex education is typically pathology-focused, unclear regarding the effects of such usage, and void of dialogue between those who actually work in the areas of sexuality education and entertainment. To address this gap, this paper is the product of joint authorship between media figures from varied sexually-focused programming fields and academics who teach and conduct research in the areas of sexuality and relational health. The authors focus on the role that various forms of entertainment media play in educating members of the public and college classrooms in the areas of sex and sexuality. Additionally, examples of the inclusion of entertainment media in educational contexts are discussed. 相似文献
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16.
Lino J. Alvarez-Vázquez Francisco J. Fernández Aurea Martínez 《Journal of The Franklin Institute》2014
This work deals with an environmental problem related to controlling eutrophication inside a sensitive zone, by means of a regulation of the wastewater discharges in the region. After setting a detailed mathematical formulation of the optimal control problem posed on a free-boundary moving domain, we present several theoretical results on existence-regularity of optimal solutions, and their characterization by a first order optimality system. In the second part of the work a complete numerical algorithm for the resolution of the control problem is proposed, and several numerical examples are also given. 相似文献
17.
Silvia Izquierdo álvarez Eva Barrio Ollero Francisco Miguel Llinares Sanjuan Fabiola Lorente Martínez María Teresa Calvo Martín 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):159-166
Introduction:
Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.Case and methods:
The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).Results:
Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.Conclusion:
The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events. 相似文献18.
Sara Baratchi Francisco J. Tovar-Lopez Khashayar Khoshmanesh Megan S. Grace William Darby Juhura Almazi Arnan Mitchell Peter McIntyre 《Biomicrofluidics》2014,8(4)
Shear stress is the major mechanical force applied on vascular endothelial cells by blood flow, and is a crucial factor in normal vascular physiology and in the development of some vascular pathologies. The exact mechanisms of cellular mechano-transduction in mammalian cells and tissues have not yet been elucidated, but it is known that mechanically sensitive receptors and ion channels play a crucial role. This paper describes the use of a novel and efficient microfluidic device to study mechanically-sensitive receptors and ion channels in vitro, which has three independent channels from which recordings can be made and has a small surface area such that fewer cells are required than for conventional flow chambers. The contoured channels of the device enabled examination of a range of shear stresses in one field of view, which is not possible with parallel plate flow chambers and other previously used devices, where one level of flow-induced shear stress is produced per fixed flow-rate. We exposed bovine aortic endothelial cells to different levels of shear stress, and measured the resulting change in intracellular calcium levels ([Ca2+]i) using the fluorescent calcium sensitive dye Fluo-4AM. Shear stress caused an elevation of [Ca2+]i that was proportional to the level of shear experienced. The response was temperature dependant such that at lower temperatures more shear stress was required to elicit a given level of calcium signal and the magnitude of influx was reduced. We demonstrated that shear stress-induced elevations in [Ca2+]i are largely due to calcium influx through the transient receptor potential vanilloid type 4 ion channel. 相似文献
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20.
José L. Arco-Tirado Francisco D. Fernández-Martín Juan-Miguel Fernández-Balboa 《Higher Education》2011,62(6):773-788
The purposes of this study were, on one had, to determine the impact of a peer tutoring program on preventing academic failure
and dropouts among first-year students (N = 100), from Civil Engineering, Economics, Pharmacy, and Chemical Engineering careers; while, on the other hand, to identify
the potential benefits of such tutoring program on the cognitive and metacognitive learning strategies and social skills of
student mentors in their last year of studies or already in a postgraduate program (N = 41) at the University of Granada (Spain). After building and selecting the measurement instruments necessary to gather
demographic and academic relevant information on both samples, and assigning first-year students to either an experimental
or control group, the intervention consisted of ten 90-min tutoring sessions during the first semester lead by student tutors
who, in turn, had undergone four 3-h training sessions on tutoring contents like planning and time management, cognitive and
metacognitive learning strategies, motivational strategies and the use of materials designed ad hoc for this program. The results show differences in favour of the treatment group on grade point average, performance rate,
success rate and learning strategies and, also, statistically significant pre-post differences for the tutors on learning
strategies and social skills. 相似文献