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Objective. Tissue inhibitor of metalloproteinase‐1 (TIMP‐1) plays a major role in the regulation of tissue growth, including cancer growth. The TIMP‐1 protein can be determined in plasma, and increased plasma levels of TIMP‐1 are associated with a poor prognosis of colorectal cancer patients. The aim of the present study was to evaluate whether tumour tissue release of the TIMP‐1 protein contributes to the increased plasma levels of TIMP‐1 observed in patients with colorectal cancer. Material and methods. Preoperative blood samples from a peripheral vein and intraoperative blood samples from a tumour artery, a tumour vein and from a peripheral vein were drawn from 24 patients undergoing elective, intended curative surgery for primary rectal cancer. TIMP‐1 levels were determined concurrently in plasma from all samples using a validated ELISA method. Counts of white blood cells and platelets were also carried out. Results. No significant differences between plasma TIMP‐1 levels could be demonstrated in any compartment. In particular, there was no significant difference in TIMP‐1 levels in plasma from tumour arteries and tumour veins. However, there was a significant decrease in neutrophil cell counts from tumour arteries to tumour veins (p<0.001). Conclusions. The present results do not support the current hypothesis that tumour cells contribute substantially to increased plasma TIMP‐1 levels observed in patients with colorectal cancer.  相似文献   
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The center of mass (COM) in functional MRI studies is defined as the center of a cerebral activation cluster. Although the COM is a well-accepted parameter for exactly localizing brain function, the reliability of COMs has not received much attention until now. Our goal was to investigate COM reliability as a function of the thresholding technique, the threshold level, and the type of COM calculation. Therefore 15 subjects were examined repeatedly using simple hand and tongue movement paradigms. Postprocessing was performed with uncorrected, corrected, and proportional thresholding as well as different threshold levels. Geometric and T-weighted COMs of left-hemispheric primary hand and tongue motor clusters were calculated. The COM variation was evaluated within and between repeated sessions depending on the different postprocessing setups. Mean COM variations over three repeated sessions varied between 1.6 mm and 9.8 mm for the hand paradigm and between 7.0 mm and 14.4 mm for the tongue task. Stringent thresholding techniques and high threshold levels were required to assess reliable results, whereas the kind of COM calculation was of lesser relevance. Thus, COM reliability cannot be presupposed; it depends strongly on the individual postprocessing techniques. This should be considered when using COMs for localizing brain function.  相似文献   
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