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排序方式: 共有10000条查询结果,搜索用时 531 毫秒
61.
Marion Tardieu Najat Salameh Line Souris David Rousseau Laurène Jourdain Hanadi Skeif François Prévot Ludovic de Rochefort Denis Ducreux Bruno Louis Philippe Garteiser Ralph Sinkus Luc Darrasse Marie Poirier-Quinot Xavier Maître 《NMR in biomedicine》2022,35(7):e4701
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain. 相似文献
62.
目的通过线性法测量皮质下缺血性血管病(SIVD)患者脑萎缩,分析其与认知功能损害的相关性。方法共纳入SIVD组50例,健康对照组50例。所有入组对象均完成一般情况评定、Mo CA量表评估认知功能、头颅MRI检查,线性法进行脑萎缩测量。结果 SIVD组代表脑室系统横径的测量值及脑沟测量值,除桥池宽度外,均较对照组显著增大(P 0. 05)。SIVD组的脑萎缩测量相对值除脑干指数外,均显著高于对照组(P 0. 05)。SIVD组双侧侧脑室两额角间最宽距离、双侧侧脑室额角两侧尾状核头间最小距离、第三脑室宽度、双侧侧脑室腰部外侧壁最小距离与Mo CA评分呈显著负相关(P 0. 05)。SIVD组脑萎缩测量相对值中的额角指数、尾状核指数、哈氏值、第三脑室宽度与视空间能力、计算力、延迟记忆和定向力均呈负相关(P 0. 05)。结论 SIVD患者存在明显的皮质和皮质下萎缩,并与认知功能损害相关。哈氏值、额角指数、尾状核指数、第三脑室宽度可作为SIVD患者脑萎缩的预测指标,提示执行功能/视空间及计算力、记忆力的损害。 相似文献
63.
PurposeType B aortic dissection is a rare but life-threatening disease. Thoracic endovascular aortic repair (TEVAR) was widely used for Type B aortic dissection patients in the last decade due to the lower mortality and morbidity compared with open chest surgical repair (OCSR). AKI in type B aortic dissection is a well-recognized complication and indicates poor short-term and long-term outcome. The objective of this concise review was to identify the risk factors and the impact of AKI on type B aortic dissection patients.Methods and resultsA literature search was performed using PubMed, Embase, MEDLINE, and Cochrane Library with the search terms ‘type B aortic dissection’ and ‘acute kidney injury’ (AKI), and all English-language literatures published in print or available online from inception through August 2020 were thoroughly reviewed. Studies that reported relative AKI risks and outcomes in type B aortic dissection patient were included. Major mechanisms of AKI in type B aortic dissection included renal hypoperfusion, inflammation response, and the use of contrast medium. Type B aortic dissection patients with AKI significantly had increased hospital stay duration, need of renal replacement therapy, and 30-d and 1-year mortality.ConclusionsAKI in type B aortic dissection is a well-recognized complication and associated with poor short-term and long-term outcome. Early identification of high-risk patients, early diagnosis of AKI, stabilization of the hemodynamic parameters, avoidance of nephrotoxic drugs, and optimization of the use of contrast agents are the major strategies for the reduction of AKI in type B aortic dissection patients. 相似文献
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65.
摘要:目的对尿液 10项肾损伤标志物检测试剂进行性能评价,并评估其临床适用性。方法对北京利德曼公司尿液a1 微球蛋白(u-a|MG)、总蛋白(u-TP)、免疫球蛋白G(u-IgG) 、微量清蛋白(u-Alb)、中性粒细胞明胶酶相关脂质运载蛋白(u-NGAL)、半胱氨酸蛋白酶抑制剂C(u-CysC).视黄醇结合蛋白(u-RBP)、β2微球蛋白(u-β2MG)、N-乙酰-β-D-氨基葡萄糖苷酶(u-NAG).、转铁蛋白(u-Trf)检测试剂盒进行性能评价。正确度和精密度验证参考美国临床和实验室标准协会(CLSI)EP15-A3,验证物质采用ERM-DA470k、ERM-DA471、B2M-NIBSC等参考物质及纯度物质;线性验证参考CLSI EP06;抗干扰能力参考CISI EP07;不同检测系统间比对参考CISI EP09。结果正确度方面,10 项标志物检测试剂测定标准物质在低值、中值、高值的偏倚分别为-2.69% ~4.67%、-3.60% ~3.33% .-2.38% ~3.02%;不精密度方面,重复性以不精密度表示,在低值和高值处分别为1.90%~5.43%、0.63% ~2.42%,室内不精密度为2.27%~5.63%、1.09%~3.41%,均满足临床要求;10项尿液标志物线性范围在0.06~4.40 mg/L至21.83~2 146.77 mg/L之间。抗干扰方面,u-1 MG、u-Alb、u-β2MG、u-Trf 、u-CysC、u-NAG分别在血红蛋白终浓度≤8 g/L、≤8 g/L、≤4 g/L、≤4 g/L、≤2g/L、≤1 g/L时,未受到明显干扰(百分偏差≤+ 10%) ,而u-TP、u-IgG、
u-RBP、u-NGAL在血红蛋白终浓度≥0.125 g/L时即受干扰。不同检测系统间偏差超出临床允许范围。结论尿液 10项肾损伤标志物的正确度、精密度、线性范围和抗血红蛋白干扰能力满足临床需要,不同检测系统间标志物测量结果可比性欠佳。 相似文献
66.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
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69.
目的 探讨重型创伤后急性弥漫性脑肿胀(PADBS)患者保守治疗与手术治疗的疗效。方法 分析 2016年1月—2019年12月该院神经外科收治的44例重型PADBS患者,根据治疗方式分为手术组和保守治疗组,统计入院时格拉斯哥昏迷量表(GCS)评分、头颅CT检查情况、伤后6个月格拉斯哥预后量表(GOS)评分等资料。结果 两组患者入院时年龄、性别及GCS评分比较,差异无统计学意义(P>0.05)。两组患者伤后6个月时GOS评分比较,差异无统计学意义(P>0.05),但两组住院时间比较,差异有统计学意义(P<0.05),手术组长于保守治疗组。结论 重型PADBS在无瞳孔变化及GCS评分下降的情况下,可密切观察病情下选择保守治疗。 相似文献
70.
Kui Li Jiawen Wang Shengxiong Liu Sen Su Chenjian Feng Xiaoxiang Fan Zhiyong Yin 《中华创伤杂志(英文版)》2015,18(2):65-73
Objective: To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.
Methods: In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.
Results: In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.
Conclusions: The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism. 相似文献