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91.
OBJECTIVE: Vessel bifurcations are prone to atherosclerotic plaque accumulation. Using volumetric intravascular ultrasound analysis, we investigated atheroma distribution at human coronary bifurcations in vivo. METHODS: We analyzed plaque distribution in 49 left anterior descending coronary artery-diagonal and 20 left circumflex coronary artery-obtuse marginal bifurcations with <50% angiographic stenosis. Cross-sections were analyzed at 1 mm intervals in segments 5 mm proximal and distal from the bifurcation. Planimetry of the lumen and external elastic membrane (EEM) was performed and plaque thickness measured at four different points relative to the branch: 0 degrees, 90 degrees, 180 degrees and 270 degrees. EEM, lumen and plaque volume and percentage plaque burden (plaque volume/EEM volume) were calculated in the proximal and distal segments. The side-branch take-off angle was analyzed in the cross-sectional images. RESULTS: Volumetric analysis showed that EEM, lumen and plaque were larger (P<0.001) in proximal segments than distal segments, whereas percent plaque burden was similar in these segments. Plaque accumulated on the opposite wall to the flow divider. Plaque distribution tended to be more eccentric in distal segments (P=0.05) compared to proximal segments. In 26 of 69 lesions, an asymmetric side-branch take-off was found and was associated with asymmetric plaque distribution compared to those lesions that had a symmetric side-branch take-off (P<0.01). CONCLUSION: We found characteristic patterns of plaque distribution at coronary bifurcations. Proximal segments demonstrated larger plaque volume than distal segments, despite similar percentages of plaque burden. Plaque volume accumulated opposite to the flow divider, especially in distal segments. The side-branch take-off angle in the cross-sectional plane influenced the plaque distribution in bifurcation lesions.  相似文献   
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Rapid tranquillization is a pharmacological intervention sometimes employed in mental health care for the management of acute behavioural disturbance. It is a form of restrictive practice, which, along with seclusion and restraint, is a conventional and controversial intervention in the therapeutic management of risk in mental health settings. This study surveyed mental health nurses practice in rapid tranquillization. A self‐report questionnaire was utilized which addressed aspects such as definitions of rapid tranquillization, presence of rapid tranquillization policy, types of incidents where it is used and postintervention monitoring. The results demonstrate that rapid tranquillization is an intervention used in the management of acute behavioural disturbance in various mental health settings in Ireland. Respondents showed a basic understanding of rapid tranquillization as an intervention; however, some areas reported not having a specific rapid tranquillization policy. There was some evidence of a variation in postrapid tranquillization monitoring of psychiatric/mental health and physical health. Service user debriefing following rapid tranquillization was reported to be common; however, the content of this was not elaborated on. In the light of variations in practice, specific training and the development of rapid tranquillization policies are recommended.  相似文献   
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IgG4-related disease is a newly recognized fibro-inflammatory condition. The purpose of this report is to present a patient with 11 years of follow-up, who revealed characteristic features of IgG4-related disease with systemic, orbital and corneal involvement and showed a favorable response to steroids and rituximab treatment.  相似文献   
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Exposure to polyunsaturated fatty acids (PUFA) influences immune function and may affect the risk of allergy development. Long chain PUFAs are produced from dietary precursors catalyzed by desaturases and elongases encoded by FADS and ELOVL genes. In 211 subjects, we investigated whether polymorphisms in the FADS gene cluster and the ELOVL2 gene were associated with allergy or PUFA composition in serum phospholipids in a Swedish birth-cohort sampled at birth and at 13 years of age; allergy was diagnosed at 13 years of age. Minor allele carriers of rs102275 and rs174448 (FADS gene cluster) had decreased proportions of 20:4 n-6 in cord and adolescent serum and increased proportions of 20:3 n-6 in cord serum as well as a nominally reduced risk of developing atopic eczema, but not respiratory allergy, at 13 years of age. Minor allele carriers of rs17606561 in the ELOVL2 gene had nominally decreased proportions of 20:4 n-6 in cord serum but ELOVL polymorphisms (rs2236212 and rs17606561) were not associated with allergy development. Thus, reduced capacity to desaturase n-6 PUFAs due to FADS polymorphisms was nominally associated with reduced risk for eczema development, which could indicate a pathogenic role for long-chain PUFAs in allergy development.  相似文献   
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BACKGROUND: The aim of this study was to compare the histomorphologic appearance of atherosclerosis in amputated legs of diabetic and non-diabetic patients. METHODS: Twenty-eight legs amputated below the knee for chronic ischaemia were studied. Fourteen legs were amputated in patients with diabetes (10 Type II, 4 nonclassified) and 14 in non-diabetics. The mean age of patients at the time of the amputation was 63.3 years in diabetics and 63.9 years in non-diabetics. Samples were taken from the main arteries at the following levels: the midleg, 5 cm above the ankle, 3 cm below the ankle and 10 cm below the ankle. Cross-sections of the arteries were examined with light microscopy and the severity of the occlusive disease determined using morphometric analysis. Medial calcification and chronic inflammation were assessed semiquantitatively. RESULTS: Arteries at 5 cm above the ankle were more severely stenotic in diabetics than in non-diabetics (p<0.05). In both diabetics and non-diabetics the posterior tibial and plantar arteries appeared to be the most stenotic. Medial calcification tended to be more prominent in diabetics than in non-diabetics. Chronic inflammation in the arterial wall occurred at the same degree in diabetics and non-diabetics. In non-diabetics chronic inflammation was more severe in the posterior tibial and plantar arteries than in the anterior tibial and dorsalis pedis arteries (p<0.04). Chronic arterial inflammation correlated with the severity of chronic arterial occlusive disease (p<0.0002). CONCLUSIONS: In diabetics occlusive disease in amputated legs is more severe in arteries above the ankle than in non-diabetics. However, no difference was demonstrated in this series in arteries of the ankle and foot. Diabetics are likely to have more medial calcification in the arteries than non-diabetics. Chronic inflammation in the arterial wall is associated with more severe stenosis.  相似文献   
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