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Background: Impulse oscillometry (IOS) has previously been proposed to provide greater sensitivity than spirometry when employed with indirect bronchoprovocation testing for the diagnosis of airway dysfunction in athletes. However, this recommendation is based on a highly selected population of symptomatic patients. Objective: To compare IOS, spirometry and respiratory symptoms following indirect bronchoprovocation in a screened cohort of athletes. Methods: One hundred and one recreational athletes were recruited. Respiratory symptoms were assessed via the Dyspnoea-12 questionnaire. Spirometry and IOS were performed pre and post a eucapnic voluntary hyperpnoea (EVH) challenge. Results: Ninety-four athletes completed the study. Sixteen athletes (17%) were positive for airway dysfunction based on spirometry (i.e. ≥10% fall in FEV1) and 17 athletes (18%) based on IOS (i.e. ≥50% increase in R5). Only nine athletes (10%) met both diagnostic thresholds. A poor relationship was observed between respiratory symptoms (i.e. Dyspnoea-12 score) and all spirometry and IOS variables. A direct relationship was observed between percentage change in R5 (r?=?0.65), Z5 (r?=?0.68), RF (r?=?0.65), AX (r?=?0.69) and the maximum fall in FEV1 (ΔFEV1max; p?<?0.001). A weak relationship was observed between R20 (r?=?0.27), X5 (r?=?0.37) and ΔFEV1max (p?<?0.01). Conclusion: Impulse oscillometry and spirometry do not concur precisely following indirect bronchoprovocation. However, IOS detects additional cases of airway dysfunction in athletes and therefore may provide diagnostic value in this population. Further work is required to establish diagnostic thresholds and fully determine the place of IOS in screening athletes for airway dysfunction.  相似文献   
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Direct oral anticoagulants (DOACs) are small molecule inhibitors of the coagulation proteases thrombin and factor Xa that demonstrate comparable efficacy to warfarin for several common indications, while causing less serious bleeding. However, because their targets are required for the normal host-response to bleeding (hemostasis), DOACs are associated with therapy-induced bleeding that limits their use in certain patient populations and clinical situations. The plasma contact factors (factor XII, factor XI, and prekallikrein) initiate blood coagulation in the activated partial thromboplastin time assay. While serving limited roles in hemostasis, pre-clinical and epidemiologic data indicate that these proteins contribute to pathologic coagulation. It is anticipated that drugs targeting the contact factors will reduce risk of thrombosis with minimal impact on hemostasis. Here, we discuss the biochemistry of contact activation, the contributions of contact factors in thrombosis, and novel antithrombotic agents targeting contact factors that are undergoing pre-clinical and early clinical testing.  相似文献   
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Granuloma annulare (GA) is an uncommon benign inflammatory skin condition, most often found on the extremities of young females. The subcutaneous variant of GA involving the penis is very rare. We report a case of subcutaneous GA associated with a urethral anomaly in a 15‐year‐old boy that persisted for a year. Treatment options are discussed with a review of the current literature.  相似文献   
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Traumatic brain injury (TBI) was shown to lead to the development of cerebral microbleeds (CMBs), which are associated with long term cognitive decline and gait disturbances in patients. The elderly is one of the most vulnerable parts of the population to suffer TBI. Importantly, ageing is known to exacerbate microvascular fragility and to promote the formation of CMBs. In this overview, the effect of ageing is discussed on the development and characteristics of TBI-related CMBs, with special emphasis on CMBs associated with mild TBI. Four cases of TBI-related CMBs are described to illustrate the concept that ageing exacerbates the deleterious microvascular effects of TBI and that similar brain trauma may induce more CMBs in old patients than in young ones. Recommendations are made for future prospective studies to establish the mechanistic effects of ageing on the formation of CMBs after TBI, and to determine long-term consequences of CMBs on clinically relevant outcome measures including cognitive performance, gait and balance function.

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Type 2 diabetes is a serious disease that is affecting an increasing part of the population in most countries. A new hypothesis is presented in this paper about the underlying causes and mechanisms that lead to the development of this disease. It is proposed that the disease is the price that the organism pays for having improved cognitive performance that is achieved through increased level of neurite growth dynamics of neurons. The suggested mechanism of the disease development involves neural centres that deal with the sensing of fat and sugar levels in the blood and cerebro-spinal fluid, the regulation of the mobilisation of these resources in the body, the regulation of the storage of sugar and fat in the body, and the regulation of feeding behaviour. The key idea of the proposed mechanism is that the hypothesised resource mobilisation neural centre overestimates the resource needs of neurons and generates and inflated resource requesting signals. The paper discusses how short- and long-term equilibrium regulation of fat and sugar resources may emerge and how this regulation may get imbalanced leading to the emergence of type 2 diabetes in the animal or human. The paper proposes a number of experimental tests that can confirm or deny the validity of the hypothesis formulated here. Possible implications for development of new drugs aimed to prevent or reduce the negative impacts of type 2 diabetes are also discussed.  相似文献   
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The case described is of a 7-year-old boy with recurrent long-segment left ventricular outflow tract obstruction. Due to previous pulmonary artery band stenosis and subsequent repair with a prosthetic patch, the pulmonary root was not intact. In this complicated Ross-Konno operation, the prosthetic patch was replaced with autologous tissue and the repaired pulmonary root was used successfully as an autograft.  相似文献   
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