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41.
《HIV clinical trials》2013,14(2):110-115
AbstractAlthough liver biopsy still remains the globally accepted gold standard for assessing liver disease, the more recent introduction of noninvasive markers in form of blood tests as well as transient elastography have led to the development of new algorithms for assessing liver disease in HIV and hepatitis coinfected individuals. Other hot topics in coinfection include need and outcome for liver organ transplantation in the increasing number of HIV-infected patients with end-stage liver disease as well as development of new agents and strategies for treatment of hepatitis B or C coinfection. 相似文献
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Xiaohua Zhou Chuang Wang Shaodong Qiu Lin Mao Fei Chen Shaona Chen 《Ultrasound in medicine & biology》2018,44(12):2759-2767
The present study investigated the potential of ultrasound shear wave elastography (SWE) in assessment of muscle stiffness in muscle injury. SWE was performed on the injured muscle in 30 New Zealand rabbits that were randomly assigned to three groups: the contusion group, which was not treated with an efficient therapeutic strategy after muscle injury; the treatment group, which was treated with a therapeutic scheme after muscle injury; and the healthy group, which was not injured and served as a control. Both the mean Young's modulus (Emean) and the maximum Young's modulus (Emax) were obtained pre-injury and 0.5, 1, 3, 5, 7, 14 and 28 d post-injury. At these time points, a rabbit in each group was randomly selected for biopsy for histopathological observation as well as comparison with Young's modulus. Eventually, all muscle tissues were collected for histologic analysis of collagen fiber formation. The contusion group had the highest Young's modulus, followed by the treatment group and then the healthy group (p < 0.05). In both the contusion and treatment groups, Emean and Emax gradually increased within 1–3 d after injury, followed by a gradual decrease. Compared with the healthy group, histopathologic analysis of the contusion and treatment groups revealed the myofibril destruction process, inflammatory reaction and myofibril regeneration. The amount of collagen fibers in the contusion group was maximal compared with the treated and healthy groups (p?=?0.001 and p < 0.001, respectively). There were more collagen fibers in the treatment group than in the healthy group (p?=?0.003). The abundance of collagen fibers was positively correlated with the value of Young's modulus (Emean: r?=?0.706, p < 0.001; Emax: r?=?0.761, p < 0.001). Thus, SWE can be used to detect pathologic changes in injured muscle and to monitor therapeutic effects. 相似文献
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冷红英 《中国初级卫生保健》2014,(1):77-79
目的评价江苏省疾病预防控制中心脊髓灰质炎(脊灰)实验室所用细胞系对脊灰病毒的敏感性,制备江苏省脊灰实验室的标准毒株(QC)。方法采用96孔微量培养板滴定法。结果江苏省脊灰实验QC3次独立的细胞敏感性实验结果的滴度波动为±0.5 log 10CCID50,同时用中国疾病预防控制中心病毒病预防控制所国家脊灰实验室提供的已知滴度的Sabin参考株(China Sabin Test Reference Strain;CSTRS)做平行对照,CSTRS株3次滴度结果与其本身提供的参考值相比较,其滴度波动也均为±0.5细10CCID50。结论江苏省脊灰实验室QC结果符合实验要求,脊灰实验室所用细胞系对脊灰病毒的敏感性未下降。是敏感、有效的。 相似文献
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Golo Petzold Melissa Porsche Volker Ellenrieder Steffen Kunsch Albrecht Neesse 《Ultrasound in medicine & biology》2019,45(2):402-410
The aim was to evaluate the influence of food intake on liver stiffness measurement (LSM), performed with 2-D shear wave elastography (Logiq E9, GE Medical Systems, Wauwatosa, WI, USA). One hundred healthy volunteers were prospectively enrolled. Mean age was 25.8 (19–55) y, and mean body mass index was 22.43 (17.3–30.8) kg/m². Patients fasted for at least 3 h and subsequently ingested a liquid meal of 800 kcal. Liver stiffness and portal vein velocity were measured before and after food intake. Food intake resulted in significantly higher LSM values compared with baseline LSM (5.74 ± 0.94 kPa vs. 4.80 ± 0.94 kPa, p < 0.001). On multiple linear regression analysis, body mass index was significantly positively correlated with the LSM increase after food intake (p?=?0.01). No correlation between the increase in LSM and the increase in post-prandial portal vein velocity was observed (r?=?0.09). In summary, food intake has a significant influence on LSM. There is an 11% risk of misclassifying non-fasting, healthy patients as having significant fibrosis. 相似文献
46.
《European journal of radiology》2014,83(1):e1-e7
PurposeTo develop and evaluate a computer-assisted method of quantifying five-point elasticity scoring system based on ultrasound real-time elastography (RTE), for classifying benign and malignant breast lesions, with pathologic results as the reference standard.Materials and methodsConventional ultrasonography (US) and RTE images of 145 breast lesions (67 malignant, 78 benign) were performed in this study. Each lesion was automatically contoured on the B-mode image by the level set method and mapped on the RTE image. The relative elasticity value of each pixel was reconstructed and classified into hard or soft by the fuzzy c-means clustering method. According to the hardness degree inside lesion and its surrounding tissue, the elasticity score of the RTE image was computed in an automatic way. Visual assessments of the radiologists were used for comparing the diagnostic performance. Histopathologic examination was used as the reference standard. The Student's t test and receiver operating characteristic (ROC) curve analysis were performed for statistical analysis.ResultsConsidering score 4 or higher as test positive for malignancy, the diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 93.8% (136/145), 92.5% (62/67), 94.9% (74/78), 93.9% (62/66), and 93.7% (74/79) for the computer-assisted scheme, and 89.7% (130/145), 85.1% (57/67), 93.6% (73/78), 92.0% (57/62), and 88.0% (73/83) for manual assessment. Area under ROC curve (Az value) for the proposed method was higher than the Az value for visual assessment (0.96 vs. 0.93).ConclusionComputer-assisted quantification of classical five-point scoring system can significantly eliminate the interobserver variability and thereby improve the diagnostic confidence of classifying the breast lesions to avoid unnecessary biopsy. 相似文献
47.
《Public Health Forum》2014,22(1):20.e1-20.e4
Measuring burnout symptoms with COPSOQ, a standardized and validated questionnaire, is an important contribution to risk assessment of work. Comparison between the results found in a certain company and datasets in the COPSOQ database allows to estimate the severity of burnout occurance and to develop suitable measures of prevention. It is essential to have reliable knowledge about the factors which influence burnout symptoms positively as well as negatively. This knowledge can be analyzed due to a large number of assessments carried out with the aim of improving occupational health. 相似文献
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Lujing Li Xinchuan Zhou Xinbao Zhao Shaoyun Hao Jiyi Yao Wenjing Zhong Hui Zhi 《Ultrasound in medicine & biology》2017,43(11):2582-2590
Non-mass breast lesions on ultrasound (US) are areas without an associated mass. The purpose of this study was to evaluate whether combining B-mode US with color Doppler US and strain elastography (SE) improves US differentiation between benign and malignant non-mass breast lesions and the decision for biopsy. In this prospective study, three different radiologists analyzed the US images of 77 non-mass lesions independently and recorded Breast Imaging Reporting and Data System (BI-RADS) categories for four data sets. The image characteristics and BI-RADS categories of the four data sets were analyzed by another radiologist. The final diagnosis was made on the basis of pathologic findings. Values for area under the receiver operating curve (AUC), sensitivity, specificity and accuracy were compared among the data sets. The AUC of B-mode US combined with both color Doppler US and SE was greater than that of B-mode US alone (0.666 vs. 0.828) (p = 0.011). The specificity of making the decision for biopsy increased from 6.5% to 38.7% when B-mode US was combined with color Doppler and SE, without a statistically significant change in sensitivity (p < 0.001). Combined use of color Doppler and SE could improve the diagnostic value of B-mode US in distinguishing benign from malignant non-mass breast lesions and the specificity of making the decision for biopsy of non-mass breast lesions. 相似文献