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61.
We prospectively investigated the feasibility of using quantitative ultrasound imaging (QUI) to assess the biceps brachii muscle (BBM) in individuals with chronic post-stroke spasticity. To quantify muscle echogenicity and stiffness, we measured QUI parameters (gray-scale pixel value and shear wave velocity [SWV, m/s]) of the BBM in three groups: 16 healthy BBMs; 12 post-stroke, non-spastic BBMs; and 12 post-stroke, spastic BBMs. The QUI results were compared with the Modified Ashworth Scale and Tardieu Scale. A total of 20 SWVs were measured in each BBM, once at elbow in 90° flexion and again at maximally achievable extension using acoustic radiation force impulse imaging. BBM pixel value was measured in gray-scale images captured at 90° elbow flexion using ImageJ software. Statistical analyses included analysis of variance for examining the difference in SWV and pixel values among the three groups; Bonferroni correction for testing the difference in SWV and pixel values in a paired group; t-test for examining the difference in SWV values measured at two elbow angles; and Pearson correlation coefficient for analyzing the correlation of QUI to Modified Ashworth Scale and Tardieu Scale. SWV significantly differed between spastic BBMs and non-spastic or healthy BBMs. For pixel values, each of the three groups significantly differed from the others at elbow 90° flexion. The difference in SWV measured between the two elbow angles was also significant (p?<0.01). A strong negative correlation was found between SWV and passive range of motion (R2?=??0.88, p?<0.0001) in spastic upper limbs. These results suggest that the use of QUI is feasible in quantitative assessment of spastic BBM.  相似文献   
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Prognosis of patients with chronic liver disease is determined by the extent and progression of liver fibrosis, which may ultimately lead to hepatocellular carcinoma (HCC). Liver biopsy (LB) is regarded as the gold standard to estimate the extent of liver fibrosis. However, because LB has several limitations, the foremost being its invasiveness, several non-invasive methods for assessing liver fibrosis have been proposed. Of these, transient elastography (TE) provides an accurate representation of the extent of liver fibrosis. Furthermore, recent studies have focused on the usefulness of TE for assessing the risk of HCC development and HCC recurrence after curative treatment, and developed novel models to calculate the risk of HCC development based on TE findings. These issues are discussed in this expert review.  相似文献   
65.
《Saudi Dental Journal》2022,34(8):779-787
This study aimed at comparing shear-bond strength (SBS) of different self-etching adhesive systems (Clearfil S3 Bond Plus, G-Premio BOND and IBond) to dentin without or with diode-laser irradiation before photo-polymerization and to determine the effect of storage and thermo-cycling on SBS of adhesive systems. Methods: The buccal surface of 84 extracted maxillary premolars was grounded to create flat surface. The specimens were allocated into 3 groups (n = 28) depending upon the adhesive systems, then each group was divided into two sub-group (I, II) (n = 14). After the placement of respective adhesive systems on the flat surface, adhesive system in group I was photo-polymerized immediately, while in group II, the adhesive systems were exposed to diode-laser before photo-polymerization. Composite cylinder (4 mm in diameter and 2 mm height) was built on the flat surface of each specimen. Then group I and II were divided into two sub-groups (n = 7) according to the storage time and thermo-cycling (1 day without thermo-cycling or 72 days with thermo-cycling) then all the specimens were stored in distilled water. The SBS was measured at the end of storage period. ANOVA, Duncan’s Multiple Range Test and independent t-test “P ≤ 0.05” were used for data analysis. Results: G-premio BOND showed the highest mean value of SBS followed by Clearfil S3 Bond plus without significant difference between them, while IBond revealed the least mean value. Laser irradiation had positive effect on the bond-strength of all tested adhesive systems. The results also showed that the storage with thermo-cycling had negative effect on the bond-strength in groups without laser irradiation for all tested adhesive systems, while for groups with laser irradiation, the reduction in the bond-strength of all tested adhesive systems was not significant. Conclusion: Diode-laser application prior to photo-polymerization of self-etch adhesive systems significantly increased the bond-strength to dentin and can increase the durability of composite adhesion.  相似文献   
66.
目的 研究操作人员的操作经验对白酸蚀粘接剂与牙釉质及磷酸酸蚀后牙釉质粘接强度的影响.方法 对90颗牛切牙进行牙体预备,暴露牙釉质粘接面,平均分给3组人员:无操作经验组(A组)、4年操作经验组(B组)和10年操作经验组(C组).每组又进一步分为非酸蚀亚组和预酸蚀亚组.非酸蚀亚组采用白酸蚀粘接剂和复合树脂进行牙釉质粘接,预酸蚀组预先使用磷酸酸蚀剂进行酸蚀处理,然后按照非酸蚀亚组的步骤粘接.测试粘接试样的抗剪切强度,即粘接强度,并进行单因素方差分析.结果 对于非酸蚀试样,A组[(16.32±5.99)MPa]与B组[(21.36± 4.07) MPa]粘接强度的差异有统计学意义(P =0.006),而A组与C组[(18.77±3.78) MPa]的差异无统计学意义(P=0.163);对于预酸蚀试样,A组[(21.34±5.62)MPa]与B组[(26.18± 3.57) MPa](P=0.007)、A组与C组[(25.35 ±4.51) MPa] (P=0.023)粘接强度的差异均有统计学意义.无论是非酸蚀试样,还是预酸蚀试样,B组与C组粘接强度的差异均无统计学意义(P=0.140和0.672).具有操作经验人员操作后的粘接强度高于没有操作经验的学生.此外,3组操作人员的非酸蚀亚组与预酸蚀亚组之间的差异均有统计学意义(A组P=0.025、B组P=0.002、C组P=0.000).预酸蚀处理增加了白酸蚀粘接剂与牙釉质的粘接强度.结论 操作经验对粘接强度有显著影响.为了获得最佳的粘接效果,不仅需要具有粘接理论基础知识,同时还需要一定的操作经验,并应严格按照说明书要求操作.  相似文献   
67.
实时剪切波弹性成像测量脾脏硬度评价肝硬化门静脉高压   总被引:1,自引:1,他引:0  
目的 探讨实时剪切波弹性成像(SWE)测量脾脏弹性对肝硬化门静脉高压患者的诊断价值。方法 收集64例肝硬化门静脉高压患者(PH组)和62例无门静脉高压的肝硬化患者(对照组),分别测量并比较两组患者的脾脏弹性、脾脏厚度及脾脏长径,并采用DeLong检验比较SWE脾脏弹性、脾脏厚度及脾脏长径诊断肝硬化门静脉高压的ROC曲线下面积,确定脾脏弹性诊断肝硬化门静脉高压的最佳临界值,并计算相应的敏感度和特异度。结果 PH组与对照组脾脏弹性、脾脏厚度及脾脏长径差异均有统计学意义(P均<0.001)。SWE脾脏弹性、脾脏厚度及脾脏长径诊断肝硬化门静脉高压的ROC曲线下面积分别为0.979、0.917和0.865,两两比较差异均有统计学意义(P均<0.05)。脾脏弹性诊断肝硬化门静脉高压的最佳临界值为19.98 kPa,敏感度和特异度分别为95.78%和94.27%。结论 SWE测量脾脏硬度诊断肝硬化门静脉高压的效能高于测量脾脏厚度和脾脏长度,对肝硬化门静脉高压有较高诊断价值。  相似文献   
68.
目的:探讨实时超声弹性成像技术在诊断子宫内膜癌浸润子宫肌层中的应用价值,以供参考。方法:随机选取2012年2月-2014年10月本院收治的子宫内膜癌浸润子宫肌层患者80例作为研究对象,所有患者均先接受实时超声弹性成像技术进行诊断,并按其诊断子宫肌层浸润程度结果分为两组,一组为浅肌层浸润,另一组为深肌层浸润。诊断后,对两组患者进行手术治疗,将患者的诊断结果与术后病理结果进行比较、分析,以此观察实时超声弹性成像技术在诊断子宫内膜癌浸润子宫肌层中的敏感度和准确度。结果:实时超声弹性成像技术的诊断结果与术后病理结果比较,差异无统计学意义(P0.05)。其中,实时超声弹性成像技术对浅肌层浸润组的灵敏度为61.25%,准确度为93.33%;对深肌层浸润组的灵敏度为38.75%,准确度为91.18%。结论:实时超声弹性成像技术在诊断子宫内膜癌浸润子宫肌层中,有肯定的应用价值,并且其诊断准确率较高,值得在临床中推广。  相似文献   
69.
目的 探讨超声弹性成像技术对乳腺肿瘤良恶性及淋巴结转移的诊断价值,为鉴别乳腺良恶性肿瘤提供新的途径.方法 对100例女性患者共123个乳腺实质性肿块及206个淋巴结进行实时组织超声弹性成像,以5分法对病灶及淋巴结软硬度进行评分,与手术病理结果对照.结果 123个乳腺肿块中,良性病变48个,恶性病变75个.206个淋巴结中,良性反应性增生159个,恶性转移性病变47个.结论 超声弹性成像对乳腺肿物良恶性鉴别诊断有较高价值,并为判断腋窝淋巴结的性质提供有价值的信息.  相似文献   
70.
This study aimed to compare the accuracy and inter- and intra-observer reproducibility of the measured elasticity between 2 shear wave elastography systems. Three breast radiologists examined 8 targets of 4 different levels of stiffness (size: 11 mm, 4 mm) in an elasticity phantom (Customized 049A Elasticity QA Phantom, CIRS, Norfolk, VA, USA) using 2 different shear wave ultrasound elastography systems: SuperSonic Imagine (SSI) (SSI, Aix en Provence, France) and ShearScan (RS-80A, Samsung Medison, Seoul, Korea). Three radiologists performed ultrasound (US) elastography examinations for the phantom lesions using 2 equipment over a 1-week interval. Intra- and inter-observer reproducibility and the accuracy of the measured elasticity were analyzed and compared between the 2 systems. The accuracy of shape was also analyzed by shape-matching between B-mode and elastography color image. Intra-class correlation coefficients (ICC) were used in statistical analysis. For measured elasticity, the intra-observer and inter-observer reproducibility were excellent in both SSI and ShearScan (0.994 and 0.998). The overall accuracy was excellent in both systems, but the accuracy in small lesions (4 mm target) was lower in SSI than ShearScan (0.780 vs 0.967). The accuracy of shape-matching on the elastography image was 59.0% and 81.4% in the SSI and ShearScan, respectively. In conclusion, the SSI and ShearScan showed excellent intra- and inter-observer reproducibility. The accuracy of the Young''s modulus was high in both the SSI and ShearScan, but the SSI showed decreased accuracy in measurement of elasticity in small targets and poor shape-matching between the B-mode image and color-coded elastography image.  相似文献   
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