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排序方式: 共有663条查询结果,搜索用时 15 毫秒
21.
Piaw CS Kiam OT Rapaee A Khoon LC Bang LH Ling CW Samion H Hian SK 《Cardiovascular and interventional radiology》2006,29(2):230-234
Background: Transesophageal echocardiography (TEE) is a trusted method of sizing atrial septal defect (ASD) prior to percutaneous closure
but is invasive, uncomfortable, and may carry a small risk of morbidity and mortality. Magnetic resonance imaging (MRI) may
be useful non-invasive alternative in such patients who refuse or are unable to tolerate TEE and may provide additional information
on the shape of the A0SD.
Purpose: To validate the accuracy of ASD sizing by MRI compared with TEE.
Method: Twelve patients (mean age 30 years; range 11–60 years) scheduled for ASD closure underwent TEE, cine balanced fast field
echo MRI (bFFE-MRI) in four-chamber and sagittal views and phase-contrast MRI (PC-MRI) with reconstruction using the two orthogonal
planes of T2-weighted images as planning. The average of the three longest measurements for all imaging modalities was calculated
for each patient.
Results: Mean maximum ASD length on TEE was 18.8 ± 4.6 mm, mean length by bFFE-MRI was 20.0 ± 5.0 mm, and mean length by PC-MRI was
18.3 ± 3.6 mm. The TEE measurement was significantly correlated with the bFFE-MRI and PC-MRI measurements (Pearson r = 0.69, p = 0.02 and r = 0.59, p = 0.04, respectively). The mean difference between TEE and bFFE-MRI measurements was −1.2mm (95% CI: −3.7, 1.3) and between
TEE and PC-MRI was 0.5 mm (95% CI: −1.9, 2.9). Bland–Altman analysis also determined general agreement between both MRI methods
and TEE. The ASDs were egg-shaped in two cases, circular in 1 patient and oval in the remaining patients.
Conclusion: ASD sizing by MRI using bFFE and phase-contrast protocols correlated well with TEE estimations. PC-MRI provided additional
information on ASD shapes and proximity to adjacent structures. 相似文献
22.
目的:研究炎宁冲剂的抗炎与解热作用。方法:采用角叉菜胶致大鼠足跖炎性肿胀。二甲苯致小鼠耳毛细血管通透性增高,以及大鼠皮下羧甲基纤维素囊中白细胞出游等急性炎症模型研究炎宁冲剂的抗炎作用。采用啤酒酵母液引起家兔发热的方法研究炎宁冲剂的解热作用。结果:炎宁冲剂对以上实验动物均具有明显的抗炎和解热作用。结论:炎宁冲剂对急性炎症具有明显的抗炎作用。对啤酒酵母液引起家兔发热具有明显解热作用。 相似文献
23.
王文志 杨定焯 蒋建军 吴涛 程晓光 周琦 卓铁军 张华俦 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 HS Barden LS Weynan KG Fqukner 孟迅吾 《中国神经再生研究》2008,12(50):9997-10000
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。
目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。
设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。
对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。
方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。
主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。
结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。
结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。 相似文献
24.
S. W. Woo PhD S. Bang HS M. W. Chung PhD S. K. Jin PhD Y. S. Kim† MD PhD S. H. Lee‡ MD PhD 《Journal of clinical pharmacy and therapeutics》2009,34(5):561-567
Background & Objective: Angiotensin converting enzyme (ACE) inhibitors are used widely in therapy for hypertension, congestive heart failure and myocardial infarction. However, coughing, one of their major adverse effects limits their use. It is documented that Asians are more liable to coughing than Europeans. The aim of this study was to investigate genetic polymorphism involved in ACE inhibitor-induced coughing.
Methods: We monitored hypertensive subjects ( n = 110) treated with ACE inhibitors, and tested for any associations between ACE inhibitor-induced coughing and polymorphisms in the genes for ACE and the bradykinin B2 receptor, which are suspected to be related to coughing.
Results & Discussion: We found no significant differences between the groups with coughing and without coughing in the frequency of ACE I/D (Insertion/Deletion) polymorphisms. One single nucleotide polymorphism was discovered in the promoter (−58T/C) and, one in intron-exon junction upsteam of exon 2 (−59C/A), of the bradykinin B2 receptor gene. However, no significant correlation was found between those genotypes or allele distributions and ACE inhibitor-induced coughing.
Conclusion: We found no significant links between polymorphisms of the ACE gene or bradykinin B2 receptor gene with ACE inhibitor-induced coughing in hypertensive Koreans. But, the topic remains controversial and requires more study. 相似文献
Methods: We monitored hypertensive subjects ( n = 110) treated with ACE inhibitors, and tested for any associations between ACE inhibitor-induced coughing and polymorphisms in the genes for ACE and the bradykinin B2 receptor, which are suspected to be related to coughing.
Results & Discussion: We found no significant differences between the groups with coughing and without coughing in the frequency of ACE I/D (Insertion/Deletion) polymorphisms. One single nucleotide polymorphism was discovered in the promoter (−58T/C) and, one in intron-exon junction upsteam of exon 2 (−59C/A), of the bradykinin B2 receptor gene. However, no significant correlation was found between those genotypes or allele distributions and ACE inhibitor-induced coughing.
Conclusion: We found no significant links between polymorphisms of the ACE gene or bradykinin B2 receptor gene with ACE inhibitor-induced coughing in hypertensive Koreans. But, the topic remains controversial and requires more study. 相似文献
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28.
JME Kovoor RD Thomas HS Chandrashekhar PN Jayakumar S Pillai SK Shankar 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):406-411
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature. 相似文献
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30.
Premedication with intramuscular dexamethasone may decrease the rate of early recurrent intussusception by amelioration of lymphoid hyperplasia. 相似文献