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61.
OBJECTIVE: The aim of this study was to visualize the arteries from the distal aorta to the ankle joint and to determine the accuracy of MR angiography for detecting stenoses and occlusions. SUBJECTS AND METHODS: Twenty-four patients with peripheral arterial occlusive disease underwent digital subtraction angiography and were examined on a 1.5-T MR scanner. The transit time for contrast material was determined with a test bolus injection. A T1-weighted three-dimensional gradient-echo sequence with short TR and TE was used for a dynamic measurement at the level of the iliac arteries, the upper leg, and the lower leg arteries. For each level a single dose of gadolinium was injected into an antecubital vein with an MR power injector. Maximal-intensity-projection reconstructions were calculated after subtraction of the first measurement at each level. Two experienced MR radiologists who were unaware of the digital subtraction angiography results interactively evaluated both the MIP reconstructions and the single slices on a workstation, first independently and then in a consensus interpretation. RESULTS: With digital subtraction angiography, 80 hemodynamically significant stenoses and 39 occlusions were detected. For the stenoses and occlusions, a sensitivity of 100% was found for MR angiography. The specificity for the assessment of stenoses and occlusions was 98% and 94%, respectively, for the iliac arteries; 98% and 94%, respectively, for the upper leg arteries; and 94% and 95%, respectively, for the lower leg arteries. Most false-positive findings of occlusion were due to metal stents present in the iliac (n = 3) and upper leg (n = 4) arteries. CONCLUSION: The MR imaging technique that we used revealed the arteries from the distal aorta to the ankle and proved to be reliable at showing arterial stenoses and occlusions.  相似文献   
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Purpose: To ascertain the views of families living with TBI patients about the nature of the problems experienced as a result of TBI, and to compare the views of Japanese family members (J-FM) and British family members (B-FM) in order to find out whether there were cultural differences in family response to TBI. Methods: Family members involved in providing care were identified by the patients. Face to face interviews were conducted with all 18 carers in B-FM and four carers in J-FM. The remaining eight carers in J-FM participated in the postal questionnaire. Questionnaires were developed to explore the nature of problems and the involvement of family such as social embarrassment. Results: Problems arising in families were almost the same reported from both groups. However families in B-FM were likely to know more about how to cope with these problems. Family members in J-FM reported more statistically significant increases in social embarrassment than those in B-FM. Conclusion: The preliminary results showed that family members living with TBI patients in both groups had experienced problems. Appropriate rehabilitation services should be developed to help families as well as TBI patients in Japan.  相似文献   
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In recent years, an increasing number of applications and products containing or using nanomaterials have become available. This has raised concerns that some of these materials may introduce new risks for humans or the environment. A clear definition to discriminate nanomaterials from other materials is prerequisite to include provisions for nanomaterials in legislation. In October 2011 the European Commission published the ‘Recommendation on the definition of a nanomaterial’, primarily intended to provide unambiguous criteria to identify materials for which special regulatory provisions might apply, but also to promote consistency on the interpretation of the term ‘nanomaterial’. In this paper, the current status of various regulatory frameworks of the European Union with regard to nanomaterials is described, and major issues relevant for regulation of nanomaterials are discussed. This will contribute to better understanding the implications of the choices policy makers have to make in further regulation of nanomaterials. Potential issues that need to be addressed and areas of research in which science can contribute are indicated. These issues include awareness on situations in which nano-related risks may occur for materials that fall outside the definition, guidance and further development of measurement techniques, and dealing with changes during the life cycle.  相似文献   
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Mycobacterium abscessus is a non‐tuberculous mycobacteria able to cause opportunistic infections in selected patient groups. During the last decades it has emerged as a cause of chronic pulmonary infection in patients with cystic fibrosis (CF). M. abscessus strains exhibit either smooth or rough colony morphology. Strains exhibiting the rough phenotype more often cause pulmonary infections in CF patients than did the smooth ones. Here, we examined phagocytosis and production of cytokines by human peripheral blood mononuclear cells, in response to M. abscessus strains with smooth and rough colony phenotype. The rough isolates all formed multicellular cords, similar to what is observed in Mycobacterium tuberculosis. Monocytes were generally unable to internalize these rough cord isolates, in contrast with the smooth ones. Furthermore, the rough M. abscessus strains induced a distinct cytokine profile differing from that induced by the smooth ones. Rough isolates induced significantly less IL‐10 and tumour necrosis factor compared to smooth strains, but more IL‐1β. Both varieties induced equal amounts of IFN‐γ, IL‐17, IL‐23, IL‐6, IL‐8 and equally little IL‐12. The ability to withstand phagocytosis might be a virulence factor contributing to the capacity of rough M. abscessus strains to give persistent pulmonary infections.  相似文献   
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In chronic myelomonocytic leukemia (CMML), colony‐forming units granulocyte/macrophage (CFU‐GM), which grow in vitro in the absence of exogenous growth factors, arise from the abnormal clone that is responsible for the overproduction of granulomonocytic cells. Previous in vitro findings including ours suggest that divergent molecular aberrations in CMML seem to converge within the GM‐CSF signaling pathway. As JAK2 is a sentinel kinase in this pathway, JAK2 inhibition may be an attractive treatment approach in CMML. We investigated the in vitro effects of the specific JAK2 inhibitor TG101209 on the autonomous CFU‐GM formation from peripheral blood mononuclear cells of patients with CMML. TG101209 was found to either block or strongly inhibit spontaneous CFU‐GM growth in all 10 patients tested. This inhibitory effect was dose dependent and significantly more pronounced as compared to the inhibitory effect on stimulated CFU‐GM growth from normal individuals. In a CMML patient with splenomegaly, who was treated with the JAK1/2 inhibitor ruxolitinib off label, we can demonstrate a spleen response and the disappearance of constitutional symptoms which was associated with a decrease in autonomous CFU‐GM formation ex vivo. Pharmacological JAK2 inhibition may be an interesting approach to be systematically studied in patients with CMML.  相似文献   
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