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81.
82.
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
83.
Robert Kollmorgen 《Arthroscopy》2019,35(3):824-825
Anatomical understanding of the peritrochanteric space and abductor insertions has been well documented in the literature. Extrapolating this knowledge to perform a “successful” abductor tendon repair has led to controversy over the best method to achieve a durable, stable repair and improve patient outcomes. I feel that the debate in the hip over single- versus double-row fixation is only beginning and we are in for a ride to uncover the best method, as we have with the shoulder over the last 15 years. What is best? Single or double row? 相似文献
84.
Darren R. Feldman MD Yasser Ged MBBS Chung-Han Lee PhD Andrea Knezevic MS Ana M. Molina MD Ying-Bei Chen PhD Joshua Chaim DO Devyn T. Coskey MS Samuel Murray MS Satish K. Tickoo MD Victor E. Reuter MD Sujata Patil PhD Han Xiao MD Jahan Aghalar MD Arlyn J. Apollo MD Maria I. Carlo MD Robert J. Motzer MD Martin H. Voss MD 《Cancer》2020,126(24):5247-5255
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86.
Luis J García-Flórez Guillermo Gómez-álvarez Ana M Frunza Luis Barneo-Serra Manuel F Fresno-Forcelledo 《World journal of gastrointestinal surgery》2015,7(9):196-202
AIM: To establish the association between lymph node involvement and the response to neoadjuvant therapy in locally advanced rectal cancer.METHODS: Data of 130 patients with mid and low locally advanced rectal adenocarcinoma treated with neoadjuvant chemoradiation followed by radical surgery over a 5-year period were reviewed. Tumor staging was done by endorectal ultrasound and/or magnetic resonance imaging. Tumor response to neoadjuvant therapy was determined by T-downstaging and tumor regression grading (TRG). Pathologic complete response (pCR) is defined as the absence of tumor cells in the surgical specimen (ypT0N0). The varying degrees TRG were classified according to Mandard’s scoring system. The evaluation of the response is based on the comparison between previous clinico-radiological staging and the results of pathological evaluation. χ2 and Spearman’s correlation tests were used for the comparison of variables.RESULTS: Pathologic complete response (pCR, ypT0N0, TRG1) was observed in 19 cases (14.6%), and other 18 (13.8%) had only very few residual malignant cells in the rectal wall (TRG2). T-downstaging was found in 63 (48.5%). Mean lymph node retrieval was 9.4 (range 0-38). In 37 cases (28.5%) more than 12 nodes were identified in the surgical specimen. Preoperative lymph node involvement was seen in 77 patients (59.2%), 71 N1 and 6 N2. Postoperative lymph node involvement was observed in 41 patients (31.5%), 29 N1 and 12 N2, while the remaining 89 were N0 (68.5%). In relation to ypT stage, we found nodal involvement of 9.4% in ypT0-1, 22.2% in ypT2 and 43.7% in ypT3-4. Of the 37 patients considered “responders” to neoadjuvant therapy (TRG1 and 2), there were only 4 N+ (10.8%) and the remainder N0 (89.2%). In the “non responders” group (TRG 3, 4 and 5), 37 cases were N+ (39.8%) and 56 (60.2%) were N0 (P < 0.001).CONCLUSION: Response to neoadjuvant chemoradiation in rectal cancer is associated with lymph node involvement. 相似文献
87.
88.
Christopher N. Cooley Tyler J. Beranek Matthew A. Warpinski Robert Alexander Amanda O. Esquivel 《The American journal of emergency medicine》2019,37(2):199-203
Introduction
In the United States there has been a large increase in participation in lacrosse for both males and females. The purpose of this study was to analyze the number of head injuries, injury rates (calculated using the reported number of participants) and types of head injuries that are seen in emergency departments in the United States.Methods
We compared injuries between male and female lacrosse participants. This was a retrospective study using a publicly available database produced by the US Consumer Product Safety Commission and information about lacrosse participation from US Lacrosse.Results
A linear regression was performed and showed a positive correlation between number of head injuries to males and time from 2002 to 2010 (R2?=?0.823; p?=?0.001). While the number of injuries to the head in female lacrosse participants was not significant. There was a negative correlation between the number of head injuries to males from 2010 to 2016 (R2?=?0.800; p?=?0.007), but again, there was no significance for female injury count (R2?=?0.417; p?=?0.117). Other significant differences between head injuries in males and females included the mechanism of injury and the type of injury recorded.Conclusion
The most recent data from 2010 to 2016, suggest that both males and females have had a decrease in injury rate. However the total number of female head injuries is not significantly decreasing and as the sport continues to grow there will likely be more total head injuries and visits to the emergency department. 相似文献89.
M. Masson Regnault J. Castañeda-Sanabria M.H.T. Diep Tran M. Beylot-Barry H. Bachelez N. Beneton O. Chosidow A. Dupuy P. Joly D. Jullien E. Mahé M.-A. Richard M. Viguier F. Tubach E. Sbidian C. Paul The PsoBioTeq Study Group 《Journal of the European Academy of Dermatology and Venereology》2020,34(2):293-300
90.