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991.
Carlos A. ávila-Orta Zoe V. Qui?ones-Jurado Miguel A. Waldo-Mendoza Erika A. Rivera-Paz Víctor J. Cruz-Delgado José M. Mata-Padilla Pablo González-Morones Ronald F. Ziolo 《Materials》2015,8(11):7900-7912
Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 1013 to 105 Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods. 相似文献
992.
Optical coherence tomography (OCT) is a noninvasive imaging tool used in vivo in real time for diagnosis, treatment delineation and monitoring of basal cell carcinoma (BCC). Features of BCC on OCT have been widely described and reviewed. However, the diagnostic accuracy of OCT in these various applications is unclear. We systematically reviewed the literature to assess the accuracy of OCT in diagnosis and management of BCC using the Embase and Medline databases. In total 179 unique references were identified in the initial search, of which 22 studies with 556 histologically proven BCCs were eligible. Assessment of the quality of eligible studies was undertaken using the STROBE criteria. Data extraction and quality assessment were performed independently by the two authors. This systematic review provides an overview of the clinical applications of OCT in the diagnosis and management of BCC. OCT has been suggested to be useful in the diagnosis, treatment planning and treatment monitoring of BCC. As the technology improves and its utility increases, further studies with good methodological quality will be needed to implement OCT into daily practice. 相似文献
993.
994.
995.
Umar Nadia K. Badshah Maaz B. Sandrasegaran Kumar Ghabril Marwan Agarwal Saurabh Tann Mark Lacerda Marco Kwo Paul Y. 《Digestive diseases and sciences》2015,60(7):2196-2200
Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be... 相似文献
996.
997.
Kimberly M. Avallone 《The Journal of asthma》2015,52(5):498-504
Objective: Despite its negative effects, smoking is more common among individuals with asthma compared to those without. Anxiety sensitivity (fear of arousal-related sensations) is associated with both smoking and asthma; however, no research, to date, has examined the interplay between these three factors. Thus, the purpose of the current study was to evaluate the mediating role of anxiety sensitivity in the association between asthma diagnosis and smoking status. Methods: The current study was a secondary analysis of data from three existing datasets of non-smokers and smokers with and without asthma (n?=?433; 56.3% female, Mage?=?34.01 years, SD?=?13.9). Participants provided information on their asthma diagnosis status and smoking status and completed self-report measures. Results: As hypothesized, after controlling for gender, race and age, there was a significant indirect effect of asthma diagnosis on smoking status through anxiety sensitivity (95% CI?=?0.07–0.48). Conclusions: These results indicate that the association between asthma diagnosis and smoking status appears to be driven, in part, by anxiety sensitivity and suggest that anxiety sensitivity may serve as an important target for prevention and intervention efforts for smokers with asthma. 相似文献
998.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献
999.
<正>Photobiomodulation (PBM)-the irradiation of cells or tissues with low-intensity red to near-infrared light-is emerging as an effective means of enhancing cell and tissue resilience and repair. As reviewed elsewhere (Gordon et al., 2019), the intracellular effects of 相似文献
1000.
K.-C. Sung D.-C. Seo S.-J. Lee M.-Y. Lee S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(5):489-495