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61.
Oesophageal atresia and tracheo‐oesophageal fistula are congenital anomalies of the oesophagus requiring surgical repair in infancy, either by open or thoracoscopic approach. Although mortality rates associated with this procedure are low, children may go on to have complications throughout childhood and into adulthood, most commonly related to ongoing gastrointestinal and respiratory symptoms. This review outlines the early, mid and long‐term outcomes for these children in terms of quality of life and incidence of symptoms.  相似文献   
62.
Rat skin grafted onto immunosuppressed mice is resistant to mouse anti-rat serum during the first 7-10 d after transplantation. It gradually acquires susceptibility, reaching a peak of sensitivity at 14-16 d after grafting. The grafts remain sensitive to antiserum, though at decreasing levels for an additional 3 wk, and grafts that persist beyond that time are resistant to antiserum for as long as they survive. In the study reported here, it is shown that the initial period of resistance to antiserum is due to factors acting locally within the graft and is entirely uninfluenced by the regimen of immunosuppression or the protective dressings that are used. After administration of antiserum, deposits of the injected immunoglobulin and of endogenous C3 are found on the luminal surfaces of graft vessels, although no significant tissue damage is observed. Rat skin that has become highly sensitive to antiserum 14-16 d after transplantation loses that sensitivity if it is regrafted to a new recipient, and then regains it 8-10 d later. Thus, the resistance of freshly grafted skin to antisera is associated with the process of healing into place, a conclusion that is supported by the observation that the intracutaneous administration of antisera to rats causes intense local inflammation and necrosis. The skin is therefore sensitive just before it is removed for grafting, but temporarily loses sensitivity thereafter. Resistance to antiserum during the first 3 or 4 d after transplantation is probably attributable to the fact that at that time grafts are vascularized poorly if at all. The state of resistance extends for several days after vascularization of the graft takes place and is then only gradually lost, a phenomenon that seems to be associated with the resistance of newly formed and regenerating blood vessels to vasoactive substances. This view is in accord with and, indeed, supports the idea that the induction of vascular injury is an essential step in antisera-mediated damage to tissue grafts.  相似文献   
63.
The survival of autologous red cells collected intraoperatively has been reported previously. This study measures the survival and half- life of red cells collected 3 hours after hip and knee arthroplasty. For six patients, four having knee replacements and two having hip replacements, the salvaged red cells were labeled with radioactive 51Cr. Peripheral blood was simultaneously labeled with nonradioactive 52Cr. There was no significant difference in the survival or half-life of the salvaged and the venous blood.  相似文献   
64.
We analyzed brain MRI data from 372 young adult twins to identify cortical regions in which gray matter thickness and volume are influenced by genetics. This was achieved using an A/C/E structural equation model that divides the variance of these traits, at each point on the cortex, into additive genetic (A), shared (C), and unique environmental (E) components. A strong genetic influence was found in frontal and parietal regions. In addition, we correlated cortical thickness with full-scale intelligence quotient for comparison with the A/C/E maps, and several regions where cortical structure was correlated with intelligence quotient are under genetic control. These cortical measures may be useful phenotypes to narrow the search for quantitative trait loci influencing brain structure.  相似文献   
65.
International Journal of Diabetes in Developing Countries -  相似文献   
66.
Brain-derived neurotrophic factor (BDNF) plays a key role in learning and memory, but its effects on the fiber architecture of the living brain are unknown. We genotyped 455 healthy adult twins and their non-twin siblings (188 males/267 females; age: 23.7±2.1 years, mean±SD) and scanned them with high angular resolution diffusion tensor imaging (DTI), to assess how the BDNF Val66Met polymorphism affects white matter microstructure. By applying genetic association analysis to every 3D point in the brain images, we found that the Val-BDNF genetic variant was associated with lower white matter integrity in the splenium of the corpus callosum, left optic radiation, inferior fronto-occipital fasciculus, and superior corona radiata. Normal BDNF variation influenced the association between subjects' performance intellectual ability (as measured by Object Assembly subtest) and fiber integrity (as measured by fractional anisotropy; FA) in the callosal splenium, and pons. BDNF gene may affect the intellectual performance by modulating the white matter development. This combination of genetic association analysis and large-scale diffusion imaging directly relates a specific gene to the fiber microstructure of the living brain and to human intelligence.  相似文献   
67.
A major challenge in neuroscience is finding which genes affect brain integrity, connectivity, and intellectual function. Discovering influential genes holds vast promise for neuroscience, but typical genome-wide searches assess approximately one million genetic variants one-by-one, leading to intractable false positive rates, even with vast samples of subjects. Even more intractable is the question of which genes interact and how they work together to affect brain connectivity. Here, we report a novel approach that discovers which genes contribute to brain wiring and fiber integrity at all pairs of points in a brain scan. We studied genetic correlations between thousands of points in human brain images from 472 twins and their nontwin siblings (mean age: 23.7 ± 2.1 SD years; 193 male/279 female). We combined clustering with genome-wide scanning to find brain systems with common genetic determination. We then filtered the image in a new way to boost power to find causal genes. Using network analysis, we found a network of genes that affect brain wiring in healthy young adults. Our new strategy makes it computationally more tractable to discover genes that affect brain integrity. The gene network showed small-world and scale-free topologies, suggesting efficiency in genetic interactions and resilience to network disruption. Genetic variants at hubs of the network influence intellectual performance by modulating associations between performance intelligence quotient and the integrity of major white matter tracts, such as the callosal genu and splenium, cingulum, optic radiations, and the superior longitudinal fasciculus.  相似文献   
68.
69.
Lipomas represent about 1 to 5% of all neoplasms of the oral cavity. Although relatively common, few large series of intraoral lipomas and its variants are seen in the literature. Therefore, the author presents the four cases of intra-oral lipoma with one case of histological variant of lipoma, the fibrolipoma. All lesions were removed surgically with the intra-oral approach and none showed recurrence.  相似文献   
70.
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