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排序方式: 共有6818条查询结果,搜索用时 15 毫秒
171.
N Fujima Y Nakamaru T Sakashita A Homma A Tsukahara K Kudo H Shirato 《Dento maxillo facial radiology》2015,44(9)
Objectives:
To investigate the diagnostic value of tumour blood flow (TBF) obtained with pseudocontinuous arterial spin labelling for the differentiation of squamous cell carcinoma (SCC) and inverted papilloma (IP) in the nasal or sinonasal cavity.Methods:
We retrospectively analysed the cases of 33 patients with SCC and 8 patients with IP in the nasal or sinonasal cavity. Pseudocontinuous arterial spin labelling scanning was performed for all patients using a 3.0-T MR unit. Quantitative TBF values were measured by two neuroradiologists by respectively delineating the whole-tumour regions of interest, and the mean of them was determined as TBF value in each patient. Additionally, the presence of imaging findings of convoluted cerebriform pattern (CCP) on MR T2 weighted images was determined in all patients. As a subgroup analysis, patients with IP were divided into aggressive and non-aggressive IPs depending on their progression range. First, an intraclass correlation coefficient (ICC) of TBF values between two neuroradiologists was determined. Next, a statistical comparison of the TBF value by a Mann–Whitney U test between the patients with SCC and IP was performed. Additionally, the comparison by an ANOVA with a post hoc test of Tukey''s method among the SCC, non-aggressive IP and aggressive IP groups was also performed. If significance was observed, the diagnostic accuracy to differentiate SCCs from IPs was calculated. Diagnostic accuracy by CCP findings alone and by the combination of CCP findings and TBF were also assessed.Results:
The ICC of TBF values between two neuroradiologists was 0.82. The mean TBF values in the patients with SCC, all patients with IP, those with aggressive IP and those with non-aggressive IP were 141.2 ± 33.1, 77.8 ± 31.5, 109.4 ± 16.7 and 58.8 ± 19.9 ml 100 g−1 min−1, respectively. A significant difference was observed between SCC and IP (p < 0.001), SCC and non-aggressive IP (p < 0.01) and non-aggressive IP and aggressive IP (p < 0.01). The diagnostic accuracy values obtained with receiver operating characteristic curve analysis for the differentiation of SCC from IP and for SCC from non-aggressive IP were 0.90 and 0.92, respectively. The diagnostic accuracy was elevated (0.95 from 0.88) by adding the TBF value to CCP findings.Conclusions:
The pseudocontinuous arterial spin labelling technique can be a useful non-invasive diagnostic tool to differentiate SCC from IP in nasal or sinonasal cavity. 相似文献172.
Comparison between T1 relaxation time of Gd‐EOB‐DTPA‐enhanced MRI and liver stiffness measurement of ultrasound elastography in the evaluation of cirrhotic liver 下载免费PDF全文
173.
174.
Yoshiyuki Shioyama Hiroshi Tsuji Hiroaki Suefuji Makoto Sinoto Akira Matsunobu Shingo Toyama Katsumasa Nakamura Sho Kudo 《International journal of urology》2015,22(1):33-39
Recent advances in external beam radiotherapy have allowed us to deliver higher doses to the tumors while decreasing doses to the surrounding tissues. Dose escalation using high‐precision radiotherapy has improved the treatment outcomes of prostate cancer. Intensity‐modulated radiation therapy has been widely used throughout the world as the most advanced form of photon radiotherapy. In contrast, particle radiotherapy has also been under development, and has been used as an effective and non‐invasive radiation modality for prostate and other cancers. Among the particles used in such treatments, protons and carbon ions have the physical advantage that the dose can be focused on the tumor with only minimal exposure of the surrounding normal tissues. Furthermore, carbon ions also have radiobiological advantages that include higher killing effects on intrinsic radio‐resistant tumors, hypoxic tumor cells and tumor cells in the G0 or S phase. However, the degree of clinical benefit derived from these theoretical advantages in the treatment of prostate cancer has not been adequately determined. The present article reviews the available literature on the use of particle radiotherapy for prostate cancer as well as the literature on the physical and radiobiological properties of this treatment, and discusses the role and the relative merits of particle radiotherapy compared with current photon‐based radiotherapy, with a focus on proton beam therapy and carbon ion radiotherapy. 相似文献
175.
Anthony W.H. Chan Jianhong Zhong Sarah Berhane Hidenori Toyoda Alessandro Cucchetti KeQing Shi Toshifumi Tada Charing C.N. Chong Bang-De Xiang Le-Qun Li Paul B.S. Lai Vincenzo Mazzaferro Marta García-Fiñana Masatoshi Kudo Takashi Kumada Sasan Roayaie Philip J. Johnson 《Journal of hepatology》2018,68(6):1284-1293
176.
Daisuke Ban Atsushi Kudo Takumi Irie Takanori Ochiai Arihiro Aihara Satoshi Matsumura Shinji Tanaka Minoru Tanabe 《Asian journal of endoscopic surgery》2015,8(1):11-15
Reduced port surgery has been attracting attention in the field of minimally invasive surgery. Although the use of SILS is becoming widespread, technical difficulty has delayed its adoption for laparoscopic liver resection. Recently, advances in laparoscopic liver resection have been made in tandem with advances in surgical skill and devices. The main driver in conventional laparoscopic liver resection's evolution to become less surgically invasive seems to be single‐incision laparoscopic liver resection (SILLR). To date, most reports on SILLR have been single case reports or case series. Only a few cohort studies on conventional laparoscopic surgery and SILLR have been conducted. Recent reports have described the use of SILLR for well‐localized lesions and solitary tumors located in the anterolateral segments of the liver or left liver lobe, but its application remains limited to partial resection and left lateral sectionectomy. The feasibility and safety of SILLR have been demonstrated, but additional work is needed for standardization of the procedure. 相似文献
177.
178.
Minatoguchi S Takemura G Chen XH Wang N Uno Y Koda M Arai M Misao Y Lu C Suzuki K Goto K Komada A Takahashi T Kosai K Fujiwara T Fujiwara H 《Circulation》2004,109(21):2572-2580
179.
Sai JK Suyama M Nobukawa B Kubokawa Y Yokomizo K Sato N 《Gastrointestinal endoscopy》2005,61(2):264-268
BACKGROUND: Pancreatobiliary reflux can occur even if the pancreaticobiliary junction is normal (occult pancreatobiliary reflux), and it may be associated with gallbladder carcinoma. The aim of the present study was to examine precancerous mucosal changes in the gallbladder from patients with occult pancreatobiliary reflux. METHODS: The mucosa of the gallbladder from 13 patients who underwent cholecystectomy was examined histopathologically. These patients had an anatomically normal pancreatobiliary junction and a biliary amylase concentration greater than 10,000 IU/L. The gallbladder of patients without carcinoma was further examined by using immunohistochemical techniques to detect Ki-67, and the results were compared with those from control patients. RESULTS: Of the 13 patients, 5 (38%) had gallbladder carcinoma and 8 (62%) did not. Of the 8 patients without carcinoma, 4 (50%) had dysplasia accompanied by hyperplasia, and 2 (25%) had hyperplasia alone of the gallbladder mucosa. The Ki-67 labeling index was significantly higher in hyperplastic and dysplastic mucosa than in control gallbladder mucosa (p < 0.0004). CONCLUSIONS: Occult pancreatobiliary reflux could be associated with precancerous mucosal changes in the gallbladder, such as hyperplasia and dysplasia with increased cellular proliferation, and could be a possible risk factor for gallbladder carcinoma. 相似文献
180.