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1.

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   
2.
Research in Science Education - The aim of this paper is to show how an innovative technique can be used to introduce a method for uncovering intrinsic mechanisms that motivate changes in...  相似文献   
3.
Within the differentiated forms of education provision, this paper intends to inquire into the causality governing the relation between the use of vouchers in education and an increased enrolment segmentation or student sorting. It does so through a comparative analysis of the quasi-market reform in Chile and the quasi-monopoly system in place in Argentina. Although from a national perspective these two countries have faced very different decentralisation reforms, they have presently arrived at similar states of their education system in terms of their enrolments' socio-economic segregation. The paper shows that vouchers are not an independent variable but an intervening one within the determinants of socio-economic segmentation. The evidence from Chile and Argentina shows that enrolment segmentation is not a consequence of the introduction of vouchers, and the causal relationship between these two variables is not a clear one. That is, the family school choice decisions brought about by the introduction of systems such as vouchers appear endogenous to a series of factors that determine such choice; factors that that are evidently important in the determination of socio-economic enrolment segmentations in non-voucher systems. This article questions the validity of the highly predominant empirical analyses which take student socio-economic characteristics and school choice decisions as independent determinant variables of student results, and intends initiating further thinking of what really lies behind the inequities in education in developing countries.  相似文献   
4.
The aim of this paper is to describe the design of chemical engineering laboratory sessions in order to focus them on the learning company approach. This is an activity carried out in the classroom similar to the activities that exist in real companies. This could lead classroom practice to a more cooperative learning and a different style of experimentation. The stated goal is to make a design that seeks to motivate students in a cooperative manner to perform their experiments self-directed and self-organised. The teaching organisation and development of participatory action research are described.  相似文献   
5.
科苏梅尔天文馆是墨西哥金塔纳罗奥州四座天文馆之一,位于加勒比海中的科苏梅尔岛上。科苏梅尔岛作为旅游胜地,每年都会接待无数慕名而来的游客。当地丰富而独具特色的旅游资源为天文馆的发展带来了机遇与挑战。在发达的旅游业氛围中,科苏梅尔天文馆的目标不仅限于服务当地公众,也期望吸引更多外国游客。科苏梅尔天文馆采取的一系列的措施,使其不仅成为了岛内的教育中心,同时也成为了游客们向往的观光目标。  相似文献   
6.
When reading in the classroom, teachers may use different methods. We examined the impact of different reading conditions on comprehension. Reading aloud involved reading the text aloud for an audience. Silent reading required the students to read the text silently. Follower reading involved listening to another student read the text aloud while having the text available for individual reading. Thirty-six fifth- and sixth-grade students read texts under the three conditions and then took comprehension tests. The students performed equally well under reading aloud and silent reading. Follower reading resulted in worse comprehension. The data suggest that the follower readers focused on their individual reading, making an effort not to listen to the student reading out loud, which consumed cognitive resources. Since reading aloud in the classroom involves not only one loud reader but also a lot of follower readers, silent reading might be the smartest choice.  相似文献   
7.
Recent calls for social justice to be a key aspect of principal preparation have been made, but content related to the efficacy of dual language education has been a neglected area of educational leadership research, coursework, and principal preparation standards. We draw on scholarship focused on dual language education, social justice leadership, and the new Professional Standards for Educational Leadership to describe how principals can create dual language programs and lead for social justice and conclude with implications for preparation programs.  相似文献   
8.
This paper reviews the international (non-U.S.) evidence on the benefits of early childhood interventions. A total of 38 contrasts of 30 interventions in 23 countries were analyzed. It focuses on studies applying a quasi-experimental or random assignment. Studies were coded according to: the type of intervention (cash transfer, nutritional, educational or mixed); sample size; study design and duration; country; target group (infants, prekindergarten); subpopulations of interventions; and dosage of intervention. Cohen's D effect sizes were calculated for four outcomes: cognitive gains; behavioral change; health gains; and amount of schooling. We find children from different context and countries receive substantial cognitive, behavioral, health and schooling benefits from early childhood interventions. The benefits are sustained over time. Interventions that have an educational or stimulation component evidenced the largest cognitive effects.  相似文献   
9.
Maximal strength, power, muscle cross-sectional area, maximal and submaximal cycling endurance characteristics and serum hormone concentrations of testosterone, free testosterone and cortisol were examined in three groups of men: weightlifters (n = 11), amateur road cyclists (n = 18) and age-matched controls (n = 12). Weightlifters showed 45-55% higher power values than road cyclists and controls, whereas the differences in maximal strength and muscle mass were only 15% and 20%, respectively. These differences were maintained when average power output was expressed relative to body mass or relative to muscle cross-sectional area. Road cyclists recorded 44% higher maximal workloads, whereas submaximal blood lactate concentration was 50-55% lower with increasing workload than in controls and weightlifters. In road cyclists, workloads associated with blood lactate concentrations of 2 and 4 mmol.l-1 were 50-60% higher and occurred at a higher percentage of maximal workload than in weightlifters or controls. Basal serum total testosterone and free testosterone concentrations were lower in elite amateur cyclists than in age-matched weightlifters or untrained individuals. Significant negative correlations were noted between the individual values of maximal workload, workloads at 2 and 4 mmol.l-1 and the individual values of muscle power output (r = -0.37 to -0.49), as well as the individual basal values of serum total testosterone and free testosterone (r = -0.39 to -0.41). These results indicate that the specific status of the participants with respect to training, resistance or endurance is important for the magnitude of the neuromuscular, physiological and performance differences observed between weightlifters and road cyclists. The results suggest that, in cycling, long-term endurance training may interfere more with the development of muscle power than with the development of maximal strength, probably mediated by long-term cycling-related impairment in anabolic hormonal status.  相似文献   
10.
ObjectiveThis study sought to analyze the prospective association between vigorous-intensity physical activity (VPA) and health-related outcomes in children and adolescents.MethodsStudies reporting associations between device-measured VPA and health-related factors in children and adolescents aged 3–18 years were identified through database searches (MEDLINE, EMBASE, and SPORTDiscus). Correlation coefficients were pooled if outcomes were reported by at least 3 studies, using DerSimonian-Laird random effects models.ResultsData from 23 studies including 13,674 participants were pooled using random effects models. Significant associations were found between VPA at baseline and overall adiposity (r = −0.09, 95% confidence interval (95%CI): –0.15 to –0.03; p = 0.002; I2 = 89.8%), cardiometabolic risk score (r = –0.13, 95%CI: –0.24 to –0.02, p = 0.020; I2 = 69.6%), cardiorespiratory fitness (r = 0.25, 95%CI: 0.15−0.35; p < 0.001; I2 = 57.2%), and total body bone mineral density (r = 0.16, 95%CI: 0.06 to 0.25; p = 0.001; I2 = 0%).ConclusionVPA seems to be negatively related to adiposity and cardiometabolic risk score and positively related to cardiorespiratory fitness and total body bone mineral density among children and adolescents at follow-up. Therefore, our findings support the need to strengthen physical activity recommendations regarding VPA due to its health benefits in children and adolescents.  相似文献   
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