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We propose a quantitative and systematic investigation of the differential pathlength factor (DPF) behavior for skeletal muscles and its dependence on different factors, such as the subcutaneous adipose tissue thickness (ATT), the variations of the tissue absorption (µa) and reduced scattering (µ′s) coefficients, and the source-detector distance. A time domain (TD) NIRS simulation study is performed in a two-layer geometry mimicking a human skeletal muscle with an overlying adipose tissue layer. The DPF decreases when µa increases, while it increases when µ′s increases. Moreover, a positive correlation between DPF and ATT is found. These results are supported by an in-vivo TD NIRS study on vastus lateralis and biceps brachii muscles of eleven subjects at rest, showing a high inter-subject and inter-muscle variability.  相似文献   
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The discrimination between active chronic hepatitis B (CHB) and the clinically quiescent infection (CIB) is not always easy, as a significant portion of patients falls in a “grey” zone. Hepatitis B core‐related antigen (HBcrAg) is a now quantifiable serological marker with potential applications in diagnosis and therapy monitoring. The aim of the present study was to evaluate the HBcrAg serum levels in HBeAg‐negative HBV infection, and its ability in identifying the clinical profile, in comparison with HBsAg serum levels. HBcrAg was retrospectively assessed on serum samples from a population of treatment‐naive HBeAg‐negative patients by ChemiLuminescent Enzyme Immunoassay (CLEIA). HBsAg and HBV‐DNA data were collected. Serological data were associated to clinical profile, defined in the subsequent follow‐up of at least 1 year. In the overall population of 160 HBeAg‐negative patients, HBcrAg results weakly correlated with qHBsAg levels (Spearman r = 0.471, < 0.0001) and correlated closely with HBV‐DNA (Spearman r = 0.746, P < 0.0001). HBcrAg levels were significantly higher in 85 CHB patients relative to 75 CIB carriers. A value of 2.5 logU/mL produced the optimal cut‐off to identify CIB patients, with diagnostic accuracy comparable to HBsAg levels. In long‐term clinical evaluation, a single measurement of HBcrAg at the established cut‐off was optimally consistent with clinical outcome. Conversely, the HBsAg cut‐off performed well in the true quiescent phase and less in more difficult‐to‐categorize patients. In conclusion, single‐point use of HBcrAg serum levels provides an accurate identification of CIB and represents a useful tool for patient classification.  相似文献   
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Macrophages play a central role in immune and tissue responses of granulomatous lung diseases induced by pathogens and foreign bodies. Circulating monocytes are generally viewed as central precursors of these tissue effector macrophages. Here, we provide evidence that granulomas derive from alveolar macrophages serving as a local reservoir for the expansion of activated phagocytic macrophages. By exploring lung granulomatous responses to silica particles in IL‐1‐deficient mice, we found that the absence of IL‐1α, but not IL‐1β, was associated with reduced CD11bhigh phagocytic macrophage accumulation and fewer granulomas. This defect was associated with impaired alveolar clearance and resulted in the development of pulmonary alveolar proteinosis (PAP). Reconstitution of IL‐1α?/? mice with recombinant IL‐1α restored lung clearance functions and the pulmonary accumulation of CD11bhigh phagocytic macrophages. Mechanistically, IL‐1α induced the proliferation of CD11blow alveolar macrophages and differentiated these cells into CD11bhigh macrophages which perform critical phagocytic functions and organize granuloma. We newly discovered here that IL‐1α triggers lung responses requiring macrophage proliferation and maturation from tissue‐resident macrophages. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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We propose a new algorithm, based on a linear regression model, to statistically estimate the hemodynamic activations in fNIRS data sets. The main concern guiding the algorithm development was the minimization of assumptions and approximations made on the data set for the application of statistical tests. Further, we propose a K-means method to cluster fNIRS data (i.e. channels) as activated or not activated. The methods were validated both on simulated and in vivo fNIRS data. A time domain (TD) fNIRS technique was preferred because of its high performances in discriminating cortical activation and superficial physiological changes. However, the proposed method is also applicable to continuous wave or frequency domain fNIRS data sets.OCIS codes: (000.5490) Probability theory, stochastic processes, and statistics; (170.2655) Functional monitoring and imaging; (170.6920) Time-resolved imaging; (170.1470) Blood or tissue constituent monitoring  相似文献   
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International Journal of Legal Medicine - When dealing with complex crimes such as rape and assault, every trace takes on an essential role. The hands are often the only means of defence and...  相似文献   
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A magnetic resonance diffusion fiber tracking study in neonate diagnosed with left hemisphere hemimegalencephaly is presented. Despite diffuse morphologic deformities identified in conventional imaging, all major pathways were identifiable bilaterally with minor aberrations in vicinity of morphologic lesions.  相似文献   
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