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21.
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22.
Miriam Delgado-Verde Javier Amores-Salvadó Gregorio Martín-de Castro José Emilio Navas-López 《知识管理研究与实践》2014,12(3):261-275
Although the importance of intellectual capital has already been highlighted in the management literature, few articles have focused on the importance of its green counterpart, green intellectual capital. Nowadays, when environmental concerns cannot be ignored by firms, it is therefore time to explore the role of green intellectual capital in environmental improvement. For that reason, our research aims to explore the relationships between green intellectual capital components and the environmental performance of the firms. In particular, we try to show the importance of green organizational and social capital in the development of environmental product innovations, which are vital to the development and implementation of environmental strategies since, as scholars have pointed out, they generate some of the greatest environmental impacts. The empirical results show that green organizational capital has an indirect impact on environmental product innovation through green social capital, meaning that the latter is a significant mediator of that relationship, and at the same time emphasizing that informal relationships play a key role in the improvement of the environmental performance of the firm and, more specifically, in the development of environmental product innovations. 相似文献
23.
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
24.
Javier Noya Salces Pedro M. Gómez-Carmona Diego Moliner-Urdiales Manuel Sillero-Quintana 《Journal of sports sciences》2014,32(13):1263-1270
AbstractThe aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively. 相似文献
25.
26.
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
27.
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29.
Miguel Á. Conde Francisco J. García-Peñalvo María J. Rodríguez-Conde Marc Alier María J. Casany Jordi Piguillem 《Interactive Learning Environments》2014,22(2):188-204
The tools used in learning processes are in a continuous state of flux. One of the most significant changes is the application of Information and Communications technologies (ICTs) to educational contexts. This provides new possible ways to carry out learning activities, new learning services, the possibility to use new kinds of contents and activities, etc. However, ICTs have not provided as many advantages as they were supposed to, so changes are necessary. In this context, a new set of tools, Web 2.0, offers a new way to understand the Web, in which the user is the centre. Further, users can cooperate in order to define contents. This concept is also applied in technology-mediated learning but there are important problems when one tries to integrate such tools and concepts with existing systems. This paper explores the integration of these tools in traditional learning environments, the various possibilities and their advantages and drawbacks. After that, an interoperability scenario is described and two experiences are presented to show how 2.0 tools can be integrated in learning activities, and its effect in educational process. 相似文献
30.