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1.
The aim of this study was to quantitatively describe the relationships between joint angles and muscle architecture (lengths (Lf) and angles (Θf) of fascicles) of human triceps surae [medial (MG) and lateral (LG) gastrocnemius and soleus (SOL) muscles] in vivo for three men-cosmonaut after long-duration spaceflight. Sagittal sonographs of MG, LG, SOL were taken at ankle was positioned at 15° (dorsiflexion), 0° (neutral position), +15°, and +30° (plantarflexion), with the knee at 90° at rest and after a long-duration spaceflight. At each position, longitudinal ultrasonic images of the MG and LG and SOL were obtained while the cosmonauts was relaxed from which fascicle lengths and angles with respect to the aponeuroses were determined. After space flight plantarflexor force declined significantly (26%; p < 0.001). The internal architecture of the GM, and LG, and SOL muscle was significantly altered. In the passive condition, Lf changed from 45, 53, and 39 mm (knee, 0°, ankle, −15°) to 26, 33, and 28 mm (knee, 90° ankle, 30°) for MG, LG, and SOL, respectively. Different lengths and angles of fascicles, and their changes by contraction, might be related to differences in force-producing capabilities of the muscles and elastic characteristics of tendons and aponeuroses. The three heads of the triceps surae muscle substantially differ in architecture, which probably reflects their functional roles. Differences in fiber length and pennation angle that were observed among the muscles and could be associated with differences in force production and in elastic properties of musculo-tendinous complex and aponeuroses.  相似文献   
2.
摘要 目的:探讨超声检查参数联合血清血管内皮生长因子(VEGF)、甲状腺球蛋白(Tg)、半乳糖血凝素-1(Gal-1)对于甲状腺癌的临床诊断价值及其与淋巴结转移的关系。方法:回顾性分析2017年6月至2020年6月入我院就诊的158例甲状腺肿瘤患者的临床资料。77例甲状腺癌患者纳入恶性组,81例甲状腺腺瘤患者纳入良性组,比较两组的超声检查参数及血清VEGF、Tg、Gal-1水平;此外,恶性组患者亚分组为淋巴结转移组(n=51)和无淋巴结转移组(n=26),比较两组超声检查参数及血清VEGF、Tg、Gal-1水平。以受试者工作特征(ROC)曲线分析超声检查参数联合血清VEGF、Tg、Gal-1对甲状腺癌的诊断效能。采用Sprearman相关系数分析各指标水平变化与甲状腺癌患者发生淋巴结转移的相关性。结果:恶性组患者的血管化指数(VI)、血流指数(FI)及血清VEGF、Tg、Gal-1水平均高于良性组患者(P<0.05);淋巴转移组患者的VI、FI及血清VEGF、Tg、Gal-1水平均高于无淋巴结转移组患者(P<0.05);超声检查参数VI、FI联合血清VEGF、Tg、Gal-1诊断甲状腺癌的曲线下面积为0.933、敏感度为85.50%、特异度为80.00%,均明显高于五项指标单独检测。Spearman相关性分析结果显示,超声检查参数VI、FI以及血清VEGF、Tg、Gal-1与甲状腺癌患者淋巴结转移均呈正相关(P<0.05)。结论:联合检测超声检查参数VI、FI及血清VEGF、Tg、Gal-1对甲状腺癌有较高的早期诊断价值,且上述指标均与患者淋巴结转移密切相关。  相似文献   
3.

Objectives:

To describe muscle size and architecture of the gastrocnemius medialis (GM) muscle in eleven adult males with Duchenne Muscular Dystrophy (DMD, age 24.5±5.4 years), and a control group of eleven males without DMD (CTRL, age 22.1±0.9 years).

Methods:

GM anatomical cross sectional area (ACSA), volume (VOL), physiological cross sectional area (PCSA), fascicle length (Lf) and pennation angle (θ) were assessed using B-Mode Ultrasonography. GM ACSA was measured at 25, 50 and 75% of muscle length (Lm), from which VOL was calculated. At 50% of Lm, sagittal plane images were analysed to determine GM Lf and θ. GM PCSA was calculated as VOL/Lf. The ratio of Lf and Lm was also calculated.

Results:

GM ACSA at 50% Lm, VOL and PCSA were smaller in DMD males compared to CTRL males by 36, 47 and 43%, respectively (P<0.01). There were no differences in Lf and θ. GM Lm was 29% shorter in DMD compared to CTRL. Lf/Lm was 29% longer in DMD (P<0.01).

Conclusions:

Unlike previous data in children with DMD, our results show significant atrophy in adult males with DMD, and no change in Lf or θ. The shorter Lm may have implications for joint flexibility.  相似文献   
4.
目的:研究彩色多普勒超声联合癌胚抗原(CEA)和糖链抗原15-3(CA15-3)检测在乳腺癌诊断中的价值。方法:选取我院2010年2月~2011年1月的98例乳腺肿块患者,患者均行彩色多普勒超声检查,采用化学发光免疫法检测血清CEA、CA-153水平,并结合常规活检和术后诊断进行统计学分析。对比三者联合检测与单一检测的敏感性、准确性。结果:彩色多普勒超声、血清CEA、CA15-3检查及三者联合检查诊断乳腺癌的敏感性、准确性分别为86.11%、30.56%、47.22%、97.22%和88.78%、73.47%、77.55%、94.90%,联合检查的准确性、敏感性高于单一检查,差异有统计学意义(P0.05)。结论:彩色多普勒超声检测方法联合CEA、CA15-3检查可提升乳腺癌诊断的准确性和敏感性,降低漏诊率。  相似文献   
5.
为了探讨超声对肺癌诊断的可行性价值,研究对象包括20例患者,20例可疑病例,均采用超声像,超声引导下穿刺活检和纤支镜检,常规病理检查,酶组织化学检查和电镜观察,结果超声诊断肺癌可以确认肺部肿块的存在,并可以观察肿瘤的大小,形态及内部结构,B超引导下活检可应用于周围型肺部肿块以及患者不宜行纤支镜检或镜检失败的某些中心型肺部肿块,肺癌组织酶组织化学活性反应为(NOS、LDH,CCO,ACP)的活性增高,SDH的活性降低,呈“四高、一是低”的特点,其超微结构示肺组织结构破坏,肺癌组织细胞结构不清,提示:超声像有助于发现肺部肿块,B超引导下活检是安全,快速,简便可行的有效手段,酶组织化学检查及电镜观察对肺癌的鉴别诊断有意义。  相似文献   
6.
目的:研究脐血管前置产前超声表现及临床效果。方法:回顾性分析2017年1月至2018年12月期间本院收治的34例脐血管前置孕妇临床资料,均进行产前超声检查,将结果与产后病理结果进行比较,分析超声表现。结果:同产后病理检查结果相比较,34例孕妇的产前超声诊断准确率、误诊率分别为97.06%、2.94%,数据对比差异无统计学意义(P>0.05),产前超声检查显示的胎盘及脐带入口情况主要为帆状胎盘、脐带胎盘边缘附着、边缘性前置胎盘、低置性前置胎盘、副胎盘等。结论:产前超声检查具有较高的脐血管前置诊断准确率,可为临床分娩结局的改善提供指导,适合推广应用在临床中。  相似文献   
7.
A cross sectional study on hepatobiliary abnormalities in opisthorchiasis was performed in 8936 males and females aged from 20 to 60 years from 90 villages of Khon Kaen province, Northeast Thailand. All were stool-examined for Opisthorchis viverrini infection by standard quantitative formalin/ethyl acetate concentration technique. Of these, 3359 participants with stool egg positive underwent ultrasonography of the upper abdomen. The hepatobiliary abnormalities detected by ultrasound are described here. This study found a significantly higher frequency of advanced periductal fibrosis in persons with chronic opisthorchiasis (23.6%), particularly in males. Risks of the fibrosis included intensity of infection, and age younger than 30 years. Height of left lobe of the liver, cross-section of the gallbladder dimensions post fatty meal, sludge, and, interestingly, intrahepatic duct stones were significantly associated with the advanced periductal fibrosis. Eleven suspected cholangiocarcinoma (CCA) cases were observed. This study emphasizes the current status of high O. viverrini infection rate and the existence of hepatobiliary abnormalities including suspected CCA in opisthorchiasis endemic areas of Thailand.  相似文献   
8.
产前胎儿磁共振成像的临床应用及研究进展   总被引:1,自引:0,他引:1  
出生缺陷已经成为影响我国人口素质的重要卫生问题,产前诊断是减少患儿出生缺陷的有效预防手段和措施。作为产前超声诊断重要补充的手段,胎儿MRI检查具有多方位、多参数、高质量、大视野成像的特点。尤其在中枢神经系统方面具有US无法比拟的优势,随着宫内治疗技术的开展和提高,其潜在的价值和应用前景越来越明显。近年来,随着各种快速MR成像方法的应用,胎儿MRI研究有了很大进步,不仅能有效地评估胎儿的正常解剖、发育变异及病理改变,而且功能MRI也正积极尝试用于胎儿正常发育及疾病的研究中。正硝地解释胎儿MRI的影像学表现仍是今后一段时间内胎儿MRI研究的方向。客观地认识MRI在产前检查中的优势与劣势、合理地应用不同的成像序列,有利于更准确地检出病变。  相似文献   
9.
Serial ultrasonic assessments of gestational sac (GS) and fetal biparietal diameter (BPD) were performed in the Japanese monkey (Macaca fuscata fuscata), rhesus monkey (Macaca mulatta), and crab-eating monkey (Macaca fascicularis). In the Japanese monkey, GS increased linearly for 3-8 weeks, whereas BPD increased in a linear-quadratic manner over 8 weeks to term. Ultrasonic assessments of spontaneously aborted fetuses with BPD growth retardation and diagnosis of a pelvic chocolate cyst also were reported.  相似文献   
10.
A total of 1205 primary school children were examined for cystic echinococcosis in five villages of Manisa, Turkey, to evaluate the efficacy of diagnostic methods of this infection in community-based screening surveys. Six hundred and thirty children from three villages, examined by a portable ultrasound scanner, chest microfilm and serological methods (ELISA, indirect hemagglutination) in our previous study, were designated as Study Group 1; and 575 children, from two adjacent villages, examined by ultrasonography alone in the present study, were designated as Study Group 2. In Study Group 1, hepatic cystic echinococcosis was detected in two cases (0.3%) by ultrasonography, while 43 (8.9%) and 49 (10.1%) cases were found to be positive for cystic echinococcosis by ELISA and indirect hemagglutination, respectively. Three of 575 children (0.5%) were diagnosed with cystic echinococcosis (two hepatic and one renal involvement) by ultrasonography alone in Study Group 2; and lung lesions were later detected in both cases with liver involvement by chest radiography.

Our results suggested that serological tests may be beneficial in suspected cases for confirmation and differential diagnosis, but have some drawbacks, such as discrepancy in results and high false seropositivity rates. Chest microfilm is not easy in field studies and exposure to X-ray is undesirable. As a reliable, simple, inexpensive and rapid technique, ultrasonography alone is recommended to be used in community-based screening surveys for cystic echinococcosis with confirmatory tests for suspected cases found during the screening program.  相似文献   

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