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1.

Introduction  

The objective of this study was to analyze health care and non-health care resource utilization under routine medical practice in a primary care setting claims database and to estimate the incremental average cost per patient per year of fibromyalgia syndrome (FMS) compared with a reference population.  相似文献   
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Copy number variation (CNV) plays a role in pathogenesis of many human diseases, especially cancer. Several whole genome CNV association studies have been performed for the purpose of identifying cancer associated CNVs. Here we undertook a novel approach to whole genome CNV analysis, with the goal being identification of associations between CNV of different genes (CNV-CNV) across 60 human cancer cell lines. We hypothesize that these associations point to the roles of the associated genes in cancer, and can be indicators of their position in gene networks of cancer-driving processes. Recent studies show that gene associations are often non-linear and non-monotone. In order to obtain a more complete picture of all CNV associations, we performed omnibus univariate analysis by utilizing dCov, MIC, and HHG association tests, which are capable of detecting any type of association, including non-monotone relationships. For comparison we used Spearman and Pearson association tests, which detect only linear or monotone relationships. Application of dCov, MIC and HHG tests resulted in identification of twice as many associations compared to those found by Spearman and Pearson alone. Interestingly, most of the new associations were detected by the HHG test. Next, we utilized dCov''s and HHG''s ability to perform multivariate analysis. We tested for association between genes of unknown function and known cancer-related pathways. Our results indicate that multivariate analysis is much more effective than univariate analysis for the purpose of ascribing biological roles to genes of unknown function. We conclude that a combination of multivariate and univariate omnibus association tests can reveal significant information about gene networks of disease-driving processes. These methods can be applied to any large gene or pathway dataset, allowing more comprehensive analysis of biological processes.  相似文献   
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Extracellular, single unit recording techniques were used to measure the responses of posterior lateral line nerve fibers to a 50-Hz dipole source that slowly changed its location along the length of the fish. The flow-field equations for a dipole source were used to model the pressure gradient pattern and thus, the expected excitation pattern along a linear array of lateral line receptor organs for different source locations. Finally, excitation patterns were similarly modeled along the left and right side of the fish's head for actual steps taken by sculpin in approach pathways to the 50-Hz dipole source. Spatial histograms of posterior lateral line nerve fiber responses to different locations of the dipole source could be predicted from pressure gradient patterns modeled from the flow-field equations, confirming that the modeling approach applied to behavioral results was a good predictor of excitation patterns likely to be encoded by the lateral line periphery. An examination of how modeled excitation patterns changed from one position to the next in typical approach pathways and how patterns differed between positions from which successful and unsuccessful strikes were launched suggests that approach and strike strategies can indeed be explained by the information available in excitation patterns. In particular, changes in the spatial distribution of pressure gradient directions (polarities), available only when the source is lateral (as opposed to directly in front of the fish), appear to enhance the ability of sculpin to determine source distance. Without such information, misses are more likely to occur and successful strikes are more likely to be launched from short distances only. Accepted: 23 October 1996  相似文献   
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