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The Wireless Capsule Endoscopy (WCE) technology allows the visualization of the whole small intestine tract. Since the capsule is freely moving, mainly by the means of peristalsis, the data acquired during the study gives a lot of information about the intestinal motility. However, due to: (1) huge amount of frames, (2) complex intestinal scene appearance and (3) intestinal dynamics that make difficult the visualization of the small intestine physiological phenomena, the analysis of the WCE data requires computer-aided systems to speed up the analysis. In this paper, we propose an efficient algorithm for building a novel representation of the WCE video data, optimal for motility analysis and inspection. The algorithm transforms the 3D video data into 2D longitudinal view by choosing the most informative, from the intestinal motility point of view, part of each frame. This step maximizes the lumen visibility in its longitudinal extension. The task of finding “the best longitudinal view” has been defined as a cost function optimization problem which global minimum is obtained by using Dynamic Programming. Validation on both synthetic data and WCE data shows that the adaptive longitudinal view is a good alternative to the traditional motility analysis done by video analysis. The proposed novel data representation a new, holistic insight into the small intestine motility, allowing to easily define and analyze motility events that are difficult to spot by analyzing WCE video. Moreover, the visual inspection of small intestine motility is 4 times faster then by means of video skimming of the WCE.  相似文献   
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The persistent air leaks due to alveolopleural fistula is not an uncommon complication of pneumothorax, particularly secondary ones. Unidirectional flow endobronchial valves initially designed for lung volume reduction are the latest tool in the therapeutic armamentarium.We present a patient with chronic obstructive pulmonary disease (COPD) with a persistent pneumothorax in spite of three pleurodesis, which was able to be resolved with the placement of two IBV? valves.  相似文献   
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All sensory stimuli produce transient excitability changes in various central nervous system circuits. One example is prepulse inhibition (PPI), which is the inhibition generated by a preceding weak stimulus (prepulse) over the reflex response to a subsequent suprathreshold stimulus. The PPI is a ubiquitous phenomenon, common to many different sensory modalities. However, it has not yet been studied with thermoalgesic stimuli. These stimuli take a relatively long time to reach their peak, which implies some uncertainty in the exact timing of prepulse effects with respect to stimulus onset. In 20 healthy volunteers, we determined when thermoalgesic stimuli cause PPI of the blink reflex and measured conscious awareness (AW) of thermoalgesic stimulus perception using the Libet's clock. In this way, we determined the temporal relationship between AW and PPI. In a second experiment, we investigated whether prepulse effects on blink reflex also involved a change in conscious perception of the supraorbital nerve stimulus. Our results show that thermoalgesic stimuli generate PPI of the blink reflex long before subjects were consciously aware of the stimulus, confirming the already‐known principle that conscious perception is not required for PPI to take place, and that prepulse stimuli induce a change in the time of conscious perception of prepulse and pulse stimuli, in such a way that AW of both stimuli tended to become closer to each other.  相似文献   
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ObjectiveThe aim of this study was to investigate the relation between health-related physical fitness and weight status in 13- to 15-year-old Latino adolescents.MethodThe final sample consisted of 73,561 adolescents aged 13–15 years (35,175 girls) from Chile (n = 48,771) and Colombia (n = 24,790). Cardiorespiratory and musculoskeletal fitness were measured using 20-m shuttle run (relative peak oxygen uptake – VO2peak) and standing broad jump test (lower body explosive strength), respectively. The International Obesity Task Force definition was used to define weight status (i.e., underweight, normal weight, overweight, and obese).ResultsThe present study found an inverted J-shape relationship between body mass index, cardiorespiratory fitness, and musculoskeletal fitness in both genders and all age groups (p < 0.01). Results also suggest that underweight adolescents, and not just overweight and obese adolescents, have lower odds of having a healthy cardiorespiratory fitness (based on new international criterion-referenced standards) profile when compared with their normal weight peers, except in girls aged 14 (p = 0.268) and 15 years (p = 0.280).ConclusionsThe present results indicate low cardiorespiratory fitness and musculoskeletal fitness levels in underweight, overweight, and obese adolescents when compared with their normal weight peers. The findings appear to suggest that exercise programs should to decrease fat mass in overweight/obese adolescents and increase muscle mass in underweight adolescents.  相似文献   
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The ability of the 134-2C2 monoclonal antibody (mAb; CD26) to transmit an activation signal and to affect T cell proliferation has been studied. The 134-2C2 mAb, although not being mitogenic by itself, is able to increase the proliferation of purified T cells in the presence of exogenous interleukin 2 (IL2) or phorbol 12-myristate 13-acetate (PMA). No effect of our mAb was observed on the proliferation of T cells induced by other stimuli such as Sepharose-bound CD3 mAb, phytohemagglutinin or calcium ionophore. Since the co-stimulatory effect of 134-2C2 mAb on PMA-induced T cell proliferation was strongly inhibited by an anti-Tac antibody, its involvement on the IL2/IL2 receptor pathway was investigated. An increased IL2 secretion in T cells cultured with PMA plus 134-2C2 mAb was observed and Northern blot analysis showed that the mAb 134-2C2 acts synergistically with PMA favoring the induction of both IL2 and interferon-γ mRNA synthesis, as well as the enhancement of IL2 receptor and transferrin receptor mRNA expression. Studies on mechanisms implicated in signal transduction showed that 134-2C2 mAb modifies neither intracellular calcium levels nor phosphoinositide breakdown. Additionally, no effect was exerted on protein kinase C translocation. These data suggest that the CD26 antigen is involved in T cell activation in an IL2/IL2 receptor-dependent pathway.  相似文献   
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