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There is no obvious difference in patient selection. The Japanese accept almost as high a proportion of diabetic patients as does the United States, and the mean age of incident patients is higher in Japan.
Renal transplantation, virtually absent in Japan, should increase mortality in U.S. dialysis patients by removing patients with the highest probability of survival, but even if one adds surviving transplant patients and studies prevalent populations, the survival rate is much better in Japan. Genetic factors are unlikely to explain differences in mortality, as older Americans live much longer than older Japanese.
We speculate that the difference lies in the practice of dialysis. Patients in the United States are generally treated by much faster and shorter dialysis than in Japan. This puts a severe burden on the cardiovascular system of older patients, leading to the poorer survival rate. Japanese physicians also appear to be better trained in dialysis and to spend more time with their patients. The nursing shortage in the United States may also contribute to the increased mortality. Whatever the explanations, the U.S. dialysis community must work to equal and, hopefully, surpass the now superior survival of Japanese dialysis patients. 相似文献
The present work proposes a solution to the challenging problem of registering two partial point sets of the same object with very limited overlap. We leverage the fact that most objects found in man-made environments contain a plane of symmetry. By reflecting the points of each set with respect to the plane of symmetry, we can largely increase the overlap between the sets and therefore boost the registration process. However, prior knowledge about the plane of symmetry is generally unavailable or at least very hard to find, especially with limited partial views. Finding this plane could strongly benefit from a prior alignment of the partial point sets. We solve this chicken-and-egg problem by jointly optimizing the relative pose and symmetry plane parameters. We present a globally optimal solver by employing the branch-and-bound paradigm and thereby demonstrate that joint symmetry plane fitting leads to a great improvement over the current state of the art in globally optimal point set registration for common objects. We conclude with an interesting application of our method to dense 3D reconstruction of scenes with repetitive objects.
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