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排序方式: 共有472条查询结果,搜索用时 15 毫秒
91.
Tomohide Hori Fumitaka Oike Hiroaki Furuyama Takafumi Machimoto Yoshio Kadokawa Toshiyuki Hata Shigeru Kato Daiki Yasukawa Yuki Aisu Maho Sasaki Yusuke Kimura Yuichiro Takamatsu Masato Naito Masaya Nakauchi Takahiro Tanaka Daigo Gunji Kiyokuni Nakamura Kiyoko Sato Masahiro Mizuno Taku Iida Shintaro Yagi Shinji Uemoto Tsunehiro Yoshimura 《World journal of gastroenterology : WJG》2016,22(47):10287-10303
Laparoscopic cholecystectomy(LC) does not require advanced techniques, and its performance has therefore rapidly spread worldwide. However, the rate of biliary injuries has not decreased. The concept of the critical view of safety(CVS) was first documented two decades ago. Unexpected injuries are principally due to misidentification of human factors. The surgeon's assumption is a major cause of misidentification, and a high level of experience alone is not sufficient for successful LC. We herein describe tips and pitfalls of LC in detail and discuss various technical considerations.Finally, based on a review of important papers and our own experience, we summarize the following mandatory protocol for safe LC:(1) consideration that a high level of experience alone is not enough;(2) recognition of the plateau involving the common hepatic duct and hepatic hilum;(3) blunt dissection until CVS exposure;(4) Calot's triangle clearance in the overhead view;(5) Calot's triangle clearance in the view from underneath;(6) dissection of the posterior right side of Calot's triangle;(7) removal of the gallbladder body; and(8) positive CVS exposure. We believe that adherence to this protocol will ensure successful and beneficial LC worldwide, even in patients with inflammatory changes and rare anatomies. 相似文献
92.
M Morishita R Shiba H Chiyo J Furuyama H Fujita Y Atsumi 《Journal of oral and maxillofacial surgery》1983,41(9):601-605
The oral manifestations of 80 reported cases of 4p- syndrome are analyzed and a new case is reported. Results indicate that the common pattern of cheilognathopharyngeal disorders in 4p- syndrome is an isolated cleft palate or a high-arched palate with micrognathia. Cases of cleft lip are only about 10% of the total. The significance of other reported aberrant phenomena cannot yet be estimated. 相似文献
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Ichiro Matsunari Yoshiharu Miyazaki Masato Kobayashi Kodai Nishi Asuka Mizutani Keiichi Kawai Akiko Hayashi Ryoko Komatsu Shoko Yonezawa Seigo Kinuya 《Annals of nuclear medicine》2014,28(5):484-497
Objective
The eXplore speCZT is a recently introduced cadmium zinc telluride-based preclinical SPECT system that has a stationary detector design with interchangeable rotating collimators. Our aim was to evaluate the performance of the eXplore speCZT using 99mTc-sources. In particular, the image quality was assessed using the National Electrical Manufacturers Association NU-4 image quality phantom as well as an in vivo mouse.Methods
Energy resolution, sensitivity and spatial resolution were measured using 99mTc sources. Image quality was assessed using NU-4 image quality phantom. The measurements were performed for 4 available collimators: (1) mouse 7-pinhole collimator (mouse PH); (2) mouse 8-slit collimator (mouse SL); (3) rat 5-pinhole collimator (rat PH); and (4) rat 5-slit collimator (rat SL). Furthermore, a mouse bone imaging study was performed using mouse PH and mouse SL.Results
The system achieved the energy resolution of 5.5 % in full-width at half maximum (FWHM) at 140 keV using a 99mTc source. Without resolution recovery function, the system provided a near millimeter transaxial and axial spatial resolution using mouse PH. Mouse SL and rat SL provided reasonably good transaxial (1.79–2.00 mm in FWHM), but much worse axial resolutions (4.55–4.96 mm in FWHM). The use of resolution recovery significantly improved spatial resolution by in average 31 ± 3 or 35 ± 4 % in FWHM or full-width at tenth maximum, respectively. In particular, a sub-millimeter resolution of 0.71 mm in FWHM was achieved in either transaxial or axial direction with mouse PH. Using NU-4 phantom, the uniformity of slit collimators as expressed as percentage standard deviation was generally better than that of pinhole collimators. The use of resolution recovery substantially improved uniformity for all the collimators tested, but caused some overestimation in recovery coefficient. Reconstruction settings such as iteration or subset number significantly affected image quality measures. Finally, bone images of acceptable quality were obtained in in vivo mouse using mouse PH with resolution recovery.Conclusions
The overall performance shows that the eXplore speCZT system is suitable for preclinical imaging-based research using small-animals. 相似文献95.
Li-air batteries have attracted considerable attention as rechargeable secondary batteries with a high theoretical energy density of 11,400 kWh/g. However, the commercial application of Li-air batteries is hindered by issues such as low energy efficiency and a short lifetime (cycle numbers). To overcome these issues, it is important to select appropriate cathode materials that facilitate high battery performance. Carbon materials are expected to be ideal materials for cathodes due to their high electrical conductivity and porosity. The physicochemical properties of carbon materials are known to affect the performance of Li-air batteries because the redox reaction of oxygen, which is an important reaction for determining the performance of Li-air batteries, occurs on the carbon materials. In this study, we evaluated the effect of the surface modification of carbon cathode materials on the charge–discharge performance of Li-air batteries using commercial Ketjenblack (KB) and KB subjected to vacuum ultraviolet (VUV) irradiation as cathodes. The surface wettability of KB changed from hydrophobic to hydrophilic as a result of the VUV irradiation. The ratio of COOH and OH groups on the KB surface increased after VUV irradiation. Raman spectra demonstrated that no structural change in the KB before and after VUV irradiation was observed. The charge and discharge capacities of a Li-air battery using VUV-irradiated KB as the cathode decreased compared to original KB, whereas the cycling performance of the Li-air battery improved considerably. The sizes and shapes of the discharge products formed on the cathodes changed considerably due to the VUV irradiation. The difference in the cycling performance of the Li-air battery was discussed from the viewpoint of the chemical properties of KB and VUV-irradiated KB. 相似文献
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Polyclonal B-Cell Lymphocytosis With Features Resembling Hairy Cell Leukemia-Japanese Variant 总被引:1,自引:0,他引:1