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21.
《Gait & posture》2016
Increased muscle co-contraction during gait is common in individuals with knee pathology, and worrisome as it is known to amplify tibiofemoral compressive forces. While knees with articular cartilage defects (ACD) are more vulnerable to compressive forces, muscle co-contraction has never been reported in this population. The purpose of this study was to evaluate the extent to which individuals with ACDs in the knee demonstrate elevated quadriceps to hamstrings muscle co-contraction on the involved limb during gait compared to the uninvolved limb and to healthy controls. We also explored the impact of participant characteristics and knee impairments on co-contraction. Twenty-nine individuals with full-thickness knee ACDs (ACD group) and 19 healthy adults (control group) participated in this study. Participants performed five gait trials at self-selected speed, during which activity of the quadriceps and hamstrings muscles were collected with surface electromyography. Three-dimensional motion capture was used to define phases of gait. Quadriceps strength and self-reported outcomes were also assessed in the same session. There were no differences in quadriceps: hamstrings co-contraction between the ACD and control groups, or between the involved and uninvolved limb for the ACD group. For both ACD and control groups, co-contraction was highest in early stance and lowest in late stance. Quadriceps strength was consistently the strongest predictor of muscle co-contraction in both the ACD and the control groups, with individuals with lower strength demonstrating greater co-contraction. Further study is needed to understand the effect of increased muscle co-contraction on joint compressive forces in the presence of varied quadriceps strength. 相似文献
22.
Fetal and Neonatal Imaging and Strategy of Primary Neonatal Heart Transplantation in Hypoplastic Left Heart with Ebstein's Anomaly 下载免费PDF全文
James M. Hammel M.D. David A. Danford M.D. Robert L. Spicer M.D. Shelby Kutty M.D. F.A.C.C. F.A.H.A. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(3):598-601
We present the anatomic constellation of mitral stenosis/aortic atresia variant of hypoplastic left heart syndrome, Ebstein's anomaly, and partial anomalous pulmonary venous return, an exceeding rare congenital heart defect. Prenatal echocardiography led to concern about the capacity of the right ventricle to increase cardiac output with lung expansion and pulmonary arterial runoff at birth, prompting the precaution of extracorporeal membrane oxygenator standby at delivery. Stage I palliation was not attempted, and control of pulmonary arterial blood flow was achieved with pulmonary artery banding, allowing sufficient ongoing hemodynamic stability. Orthotopic cardiac transplantation, repair of hypoplastic aortic arch, and primary sutureless repair of left pulmonary veins was performed, using dual‐site arterial cannulation and continuous mild hypothermic cardiopulmonary bypass. We discuss how this unique echocardiographic anatomy influenced the surgical decision and point out how it guided therapy toward a strategy of primary transplantation rather than standard staged surgical palliation. 相似文献
23.
Wojciech Szychta M.D. Ph.D. Gheorghe Cerin M.D. Ph.D. F.E.S.C. Bogdan Adrian Popa M.D. Armienti Felice M.D. Guido Lanzillo M.D. Ph.D. Marco Diena M.D. Grzegorz Opolski M.D. Ph.D. F.E.S.C. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1040-1043
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning. 相似文献
24.
Michelle A Smith Rowan Michael Rolands G Aravindan Soma Dash Syed I Shah Deni S Galileo Patricia A Martin-DeLeon 《Asian journal of andrology》2015,17(2):261-268
Titanium dioxide (TiO2) nanoparticles (TNPs) are widely used commercially and exist in a variety of products. To determine if anatase TNPs (ATNPs) in doses smaller than previously used reach the scrotum after entry in the body at a distant location and induce sperm defects, 100% ATNP (2.5 or 5 mg kg−1 body weight) was administered intraperitoneally to adult males for three consecutive days, followed by sacrifice 1, 2, 3, or 5 weeks later (long-) or 24, 48 or 120 h (short-term exposure). Transmission electron microscopy revealed the presence of ANTP in scrotal adipose tissues collected 120 h postinjection when cytokine evaluation showed an inflammatory response in epididymal tissues and fluid. At 120 h and up to 3 weeks postinjection, testicular histology revealed enlarged interstitial spaces. Significantly increased numbers of terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling-positive (apoptotic) germ (P = 0.002) and interstitial space cells (P = 0.04) were detected in treated males. Caudal epididymal sperm from the short-term, but not a long-term, arm showed significantly (P < 0.001) increased frequencies of flagellar abnormalities, excess residual cytoplasm (ERC), and unreacted acrosomes in treated versus controls (dose-response relationship). A novel correlation between ERC and unreacted acrosomes was uncovered. At 120 h, there were significant decreases in hyperactivated motility (P < 0.001) and mitochondrial membrane potential (P < 0.05), and increased reactive oxygen species levels (P < 0.00001) in treated versus control sperm. These results indicate that at 4–8 days postinjection, ANTP induce structural and functional sperm defects associated with infertility, and DNA damage via oxidative stress. Sperm defects were transient as they were not detected 10 days to 5 weeks postinjection. 相似文献
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26.
赵亮亮 《中国CT和MRI杂志》2021,(2)
目的探讨128层CT血管造影心肌桥-壁冠状动脉(MB-MCA)图像特征及与冠脉动脉粥样硬化的相关性。方法收集2018年1月至12月于我院进行冠状动脉成像检查的126例患者临床及影像学资料,总结所有患者MB-MCA检出率情况及与冠状动脉硬化的相关性。结果126例患者MB-MCA检出率为65.08%,其中LAD中段检出率最高,浅表型最为多见;CT检出位于MB-MCA近侧动脉硬化斑块发生率最高(63.41%,P<0.05),检出MB-MCA患者斑块检出率为(52.22%)与未检出MB-MCA患者斑块检出率(45.45%)比较无差异(P>0.05);且CT检出MB-MCA患者累及段数和斑块的狭窄程度与未检出MB-MCA患者相比较无统计学意义(P>0.05),但检出MB-MCA患者的斑块主要分布于动脉近段,而未检出MB-MCA患者的斑块主要位于中段和远段(P<0.05)。结论128层CT血管造影可较好地检出MB-MCA,且主要好发于LAD,以浅表型更为多见。但MB-MCA的形成与冠状动脉硬化无直接联系,当MB出现收缩和功能血流减少的时候可能会导致冠状动脉硬化的形成。 相似文献
27.
Transradial interventions (TRI) are becoming increasingly popular because of accumulating recent evidence suggesting improved survival and reduced morbidity. Complications, though rare, do occur, especially for operators on their learning curve. The complications are best prevented by utilization of proper technique. Forearm hematoma are preventable and easy to treat, but a delay in detecting and managing them can lead to disastrous consequences compartment syndrome being the most dreaded one. This review deals with tips and tricks to prevent as also treat the common and rare complications. 相似文献
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29.
目的探讨胫前动脉踝上穿支皮瓣修复足踝部软组织缺损的临床疗效。方法回顾性研究2018年4月至2019年6月采用胫前动脉踝上穿支皮瓣修复足踝部软组织缺损19例的资料,其中男11例,女8例;年龄为21~75岁,平均39岁。根据前踝上穿支皮瓣解剖学基础,按照足踝部软组织缺损大小和形状,在小腿下端前外侧设计并切取皮瓣转位修复创面。切取胫前动脉踝上穿支皮瓣面积为6.0 cm×5.0 cm^14.0 cm×8.0 cm,均为带蒂皮瓣转位。根据皮瓣成活、感染控制、弹性色泽、外观形态、供区瘢痕、皮肤感觉、患者认可等情况,对患者足踝部软组织缺损的修复情况进行综合评价。结果本组19例皮瓣全部成活,软组织缺损、肌腱、骨质及钢板外露均得以修复。供区均I期愈合。术后门诊随访2~16个月,皮瓣血运良好,颜色接近周围正常皮肤,臃肿不明显,患者对外观表示满意;供区皮片愈合良好,无明显增生、挛缩及溃疡,踝关节功能良好。结论胫前动脉踝上穿支皮瓣是修复足踝部软组织缺损较为理想的方法之一,手术操作简便,穿支较恒定,血供可靠,具有一定的临床应用价值。 相似文献
30.
《The Surgical clinics of North America》2022,102(5):809-820