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Ashish Raj Honglei Zhang Martin R Prince Yi Wang Ramin Zabih 《Magnetic resonance in medicine》2006,55(3):649-658
Time-resolved contrast enhanced magnetic resonance angiography (MRA) may suffer from involuntary patient motion. It is noted that while MR signal change associated with motion is large in magnitude and has smooth phase variation in k-phase, signal change associated with vascular enhancement is small in magnitude and has rapid phase variation in k-space. Based upon this observation, a novel projection onto convex sets (POCS) algorithm is developed as an automatic iterative method to remove motion artifacts. The presented POCS algorithm consists of high-pass phase filtering and convex projections in both k-space and image space. Without input of detailed motion knowledge, motion effects are filtered out, while vasculature information is preserved. The proposed method can be effective for a large class of nonrigid motions, including through-plane motion. The algorithm is stable and converges quickly, usually within five iterations. A double-blind evaluation on a set of clinical MRA cases shows that a completely unsupervised version of the algorithm produces significantly better rank scores (P=0.038) when compared to angiograms produced manually by an experienced radiologist. 相似文献
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Marc G Weisskopf Honglei Chen Michael A Schwarzschild Ichiro Kawachi Alberto Ascherio 《Movement disorders》2003,18(6):646-651
Anxiety disorders are common in Parkinson's disease (PD). However, the risk of PD among people with anxiety has not been examined in a prospective cohort study. We examined this relation prospectively within the Health Professionals Follow-Up Study, a cohort of US male health professionals. In 1988, anxiety was assessed using the Crown-Crisp phobic anxiety index in 35,815 men without PD, stroke, or cancer at baseline. There were 189 incident cases of PD during 12 years of follow-up. After adjusting for age, smoking, and caffeine intake, the relative risk of PD among men with the highest level of anxiety (Crown-Crisp index scores of 4 and above) was 1.5 (95% CI = 1.0-2.1; P-trend = 0.01) compared to men with the lowest level of anxiety. This positive association persisted after excluding cases of PD with onset in the first 2 years of follow-up. Use of anxiolytic medication was also associated with an elevated risk of PD (RR= 1.6; 95% CI = 0.9-3.1), but adjusting for this potential confounder did not materially affect the association between anxiety and risk of PD. Our results suggest that anxiety is a risk factor for PD. Whether this association is causal or the result of shared underlying biology remains a question. 相似文献
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茎突CT薄层冠状扫描在诊断茎突过长综合征中的价值 总被引:1,自引:2,他引:1
目的 探讨“一点一线垂直法”茎突CT薄层冠状扫描在诊断茎突过长中的价值。方法测量72例双侧茎突的长度、方位、形态、厚度、尖端与咽侧壁距离,总结茎突过长病人的临床症状与诊断。 结果 ①41例67侧长度超过3.0cm,符合茎突过长的诊断;②12例12侧茎突虽未超过3.0cm(均在2.5~2.9cm),且茎突方位角>20°、末端与咽侧壁的距离<20mm,并有临床症状的应考虑茎突过长综合征;③按茎突的形态进行分型:锥型(分直锥、弧锥),束状型,分节型,发育不良型。其中分节型与临床症状有密切关系。结论 ①茎突CT薄层冠状扫描能清晰显示茎突的长度、形态、厚度、末端与咽侧壁距离,是诊断茎突过长的一种可靠方法;②“一点一线垂直法”茎突CT薄层冠状扫描无需进行图像重建,可操作性强、简捷易行、便于推广。 相似文献
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溃疡性结肠炎大鼠肠黏膜PPAR γ的表达 总被引:1,自引:0,他引:1
目的 :观察溃疡性结肠炎 (ulcerativecolitis,UC)大鼠肠黏膜中过氧化物酶体增殖物激活受体γ(PPARγ)的表达。方法 :采用免疫组化法检测了10只UC大鼠 (UC组 )和10只正常对照组大鼠结肠黏膜中PPARγ的表达情况。结果 :UC组和对照组大鼠结肠上皮PPARγ阳性细胞分别为 (11.7±3.46)个和 (81.8±15.73)个 ,UC大鼠结肠上皮PPARγ的表达明显低于对照组(P<0.001)。结论 :UC大鼠结肠黏膜上皮PPARγ的表达明显下降 ,其可能与UC的发病有关 相似文献
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DPC4基因在非小细胞肺癌中的表达及其与微血管形成的关系 总被引:1,自引:0,他引:1
目的:研究DPC4(deleted in pancreatic carcinoma locus 4,DPC4)基因在非小细胞肺癌NSCLC中的表达及其与血管内皮生长因子(VEGF)表达和肿瘤内微血管密度(MVD)的关系。方法:利用免疫组织化学SP法检测52例NSCLC组织、19例相应的癌旁正常肺组织中DPC4、VEGF的表达和MVD值。结果:DPC4在肺癌原发灶中的阳性表达率为63.5%(33/52),与癌旁正常肺组织中的阳性表达率89.5%(17/19)相比,DPC4阳性表达水平显著降低,差别有显著性意义(P<0.05);DPC4与组织学类型、肿瘤细胞分化程度无关(P>0.05),但与淋巴结转移显著相关(P<0.05)。52例NSCLC中,DPC4的表达与VEGF、MVD值均呈负相关。结论:DPC4的低表达可能是肺癌发生过程的早期事件,并可通过直接或间接的作用促进肺癌血管生成,从而促进肺癌的淋巴结转移。 相似文献
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目的:检测Fas相关死亡结构域蛋白(Fas—associated death domain protein,FADD)基因在人非小细胞肺癌(non—small cell lung cancer,NSCLC)中的突变情况,以探讨该基因在肺癌发生发展中的作用及机制。方法:采用聚合酶链反应-单链构象多态性分析(polymerase chain reaction and single—strand conformation polymorphism,PCR—SSCP)检测74例NSCLC原发灶癌组织及13例癌旁正常肺组织中FADD基因突变情况。结果:74例NSCLC组织中检出5例发生FADD基因突变,FADD基因突变与癌的淋巴结转移呈显著正相关(ri=0.378,P=0.001),与其它临床病理特征无关。结论:NSCLC中存在着FADD基因突变。FADD基因突变在NSCLC的发生发展中可能起着重要作用。 相似文献
8.
目的:以苏州市为例,研究中医药文化软实力现状,探讨苏州目前中医药文化建设方面存在的优势和不足,并提出对策和建议。方法:根据调研及文献检索等方法,从知识生产力、价值影响力、体制引导力、社会影响力等四个方面分析苏州市中医药文化软实力现状。结果:①知识生产力:苏州市省名中医人数仅次于南京市、论文发表逐年增加,而专利方面苏州中医院少于江苏省其他地市和中医药企业,连续五年专利申请量下降;②价值影响力:中医类别医院服务能力不断提升,研究生录取分数线高,能提供优质中医药服务并吸引优秀中医人才;③体制引导力:政府积极采取各项政策激励中医药发展;④社会影响力:吴门医派作为苏州中医药文化的代表,影响国内外。结论:分析苏州中医药优势,针对不足提出对策和建议,提升苏州中医药文化软实力建设。 相似文献
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Annemarie Weissenbacher Honglei Huang Tomas Surik Maria L. Lo Faro Rutger J. Ploeg Constantin C. Coussios Peter J. Friend Benedikt M. Kessler 《American journal of transplantation》2021,21(5):1740-1753
We describe a proteomics analysis to determine the molecular differences between normothermically perfused (normothermic machine perfusion, NMP) human kidneys with urine recirculation (URC) and urine replacement (UR). Proteins were extracted from 16 kidney biopsies with URC (n = 8 donors after brain death [DBD], n = 8 donors after circulatory death [DCD]) and three with UR (n = 2 DBD, n = 1 DCD), followed by quantitative analysis by mass spectrometry. Damage-associated molecular patterns (DAMPs) were decreased in kidney tissue after 6 hours NMP with URC, suggesting reduced inflammation. Vasoconstriction was also attenuated in kidneys with URC as angiotensinogen levels were reduced. Strikingly, kidneys became metabolically active during NMP, which could be enhanced and prolonged by URC. For instance, mitochondrial succinate dehydrogenase enzyme levels as well as carbonic anhydrase were enhanced with URC, contributing to pH stabilization. Levels of cytosolic and the mitochondrial phosphoenolpyruvate carboxykinase were elevated after 24 hours of NMP, more prevalent in DCD than DBD tissue. Key enzymes involved in glucose metabolism were also increased after 12 and 24 hours of NMP with URC, including mitochondrial malate dehydrogenase and glutamic-oxaloacetic transaminase, predominantly in DCD tissue. We conclude that NMP with URC permits prolonged preservation and revitalizes metabolism to possibly better cope with ischemia reperfusion injury in discarded kidneys. 相似文献