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81.
Hidenori Kanazawa Kenichi Utano Shigeyoshi Kijima Takahiro Sasaki Yasuyuki Miyakura Hisanaga Horie Yoshikazu Nakamura Hideharu Sugimoto 《Japanese journal of radiology》2014,32(5):274-281
Objectives
The purpose of this study was to compare the degree of colorectal distention between manual insufflation using room air and automatic insufflation using carbon dioxide for computed tomography colonography performed as a preoperative examination for patients with colon cancer.Materials and methods
Participants comprised 200 patients who underwent computed tomography colonography immediately after colonoscopy from October 2011–2012. The first 100 patients were examined using manual insufflation, and the remaining 100 patients were examined using automated insufflation. Two radiologists independently assessed colorectal distention using a 4-point scale in six segments: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Mean scores of the two radiologists were used to analyze whether any differences existed between techniques in terms of the degree of distention per segment.Results
Mean distention values for the colonic lumen were better using the automated technique than with the manual technique in both positions (p < 0.05). In segments, distention was significantly better using the automated technique than using the manual technique in the sigmoid and descending colon for prone patients, and in all segments for supine patients.Conclusions
Automated carbon dioxide insufflation offered significantly improved colorectal distention scores compared to manual room air insufflation. 相似文献82.
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
83.
Shuetsu Fukushi Hideki Tani Tomoki Yoshikawa Masayuki Saijo Shigeru Morikawa 《Viruses》2012,4(10):2097-2114
The family Arenaviridae, genus Arenavirus, consists of two phylogenetically independent groups: Old World (OW) and New World (NW) complexes. The Lassa and Lujo viruses in the OW complex and the Guanarito, Junin, Machupo, Sabia, and Chapare viruses in the NW complex cause viral hemorrhagic fever (VHF) in humans, leading to serious public health concerns. These viruses are also considered potential bioterrorism agents. Therefore, it is of great importance to detect these pathogens rapidly and specifically in order to minimize the risk and scale of arenavirus outbreaks. However, these arenaviruses are classified as BSL-4 pathogens, thus making it difficult to develop diagnostic techniques for these virus infections in institutes without BSL-4 facilities. To overcome these difficulties, antibody detection systems in the form of an enzyme-linked immunosorbent assay (ELISA) and an indirect immunofluorescence assay were developed using recombinant nucleoproteins (rNPs) derived from these viruses. Furthermore, several antigen-detection assays were developed. For example, novel monoclonal antibodies (mAbs) to the rNPs of Lassa and Junin viruses were generated. Sandwich antigen-capture (Ag-capture) ELISAs using these mAbs as capture antibodies were developed and confirmed to be sensitive and specific for detecting the respective arenavirus NPs. These rNP-based assays were proposed to be useful not only for an etiological diagnosis of VHFs, but also for seroepidemiological studies on VHFs. We recently developed arenavirus neutralization assays using vesicular stomatitis virus (VSV)-based pseudotypes bearing arenavirus recombinant glycoproteins. The goal of this article is to review the recent advances in developing laboratory diagnostic assays based on recombinant viral proteins for the diagnosis of VHFs and epidemiological studies on the VHFs caused by arenaviruses. 相似文献
84.
85.
86.
Okuda R Kinoshita M Morikawa J Jotoku T Abe M 《Clinical orthopaedics and related research》2002,(396):173-178
The results of a dome-shaped osteotomy of the proximal third of the fifth metatarsal in patients with symptomatic bunionette deformity were reviewed. The series was comprised of eight patients (10 feet; mean age of patients, 21 years). The average followup was 30 months. All patients were free from pain at the fifth metatarsophalangeal joint and were satisfied with the results of this procedure. The mean angle between the longitudinal axes of the fifth metatarsal and the proximal phalanx was 18.9 degrees before surgery and 2.6 degrees after surgery. The mean angle between the longitudinal axes of the fourth and fifth metatarsals was 12.2 degrees before surgery and 4.8 degrees after surgery. The overall results were good in all 10 feet. Three feet had delayed union at the osteotomy site, but union was obtained in all feet. The osteotomy site of the fifth metatarsal in feet with delayed union was more proximal than that of the other feet. Therefore, proximal osteotomy of the fifth metatarsal should be done not at the base, but at the proximal site of the diaphysis to prevent delayed union. A proximal dome-shaped osteotomy corrects the deformity and relieves the symptoms, but careful attention should be paid to the osteotomy site. 相似文献
87.
Nakamura T Maruyama K Kashiwabara H Sunayama K Ohata K Fukazawa A Yasumi K Sugimura H Nakamura S 《Surgery today》2002,32(3):282-284
We report herein a rare case of diverticulitis causing a high serum level of carbohydrate antigen (CA) 19-9. A 52-year-old
man was admitted to our hospital with lower abdominal pain. Laboratory data showed evidence of inflammation and a high serum
level of CA 19-9 (370 U/ml). Computed tomography demonstrated thickening of the wall of the sigmoid colon. He was diagnosed
as having diverticulitis of the sigmoid colon and was treated with antibiotics. Although his symptoms improved, the presence
of a malignancy such as colorectal cancer could not be completely ruled out because of the persistently high serum level of
CA19-9. A laparotomy was performed and the sigmoid colon was found to be adherent to the bladder. Under a diagnosis of diverticulitis,
a sigmoidectomy was performed. Pathological examination revealed diverticulitis of the sigmoid colon, but there was no evidence
of malignancy in the resected specimen. The serum CA19-9 level decreased to normal postoperatively and immunohistochemical
staining revealed CA19-9 antigen in the cytoplasm of the diverticular epithelium. Therefore, a possible explanation for the
high level of this tumor marker was diverticulitis of the sigmoid colon.
Received: June 6, 2001 / Accepted: September 11, 2001 相似文献
88.
Atsushi Takeno MD Ichiro Takemasa MD Shigeto Seno PhD Makoto Yamasaki MD Masaaki Motoori MD Hiroshi Miyata MD Kiyokazu Nakajima MD Shuji Takiguchi MD Yoshiyuki Fujiwara MD Toshiro Nishida MD Toshitsugu Okayama PhD Kenichi Matsubara PhD Yoichi Takenaka PhD Hideo Matsuda PhD Morito Monden MD Masaki Mori MD Yuichiro Doki MD 《Annals of surgical oncology》2010,17(4):1033-1042
Background
Peritoneal relapse is the most common pattern of tumor progression in advanced gastric cancer. Clinicopathological findings are sometimes inadequate for predicting peritoneal relapse. The aim of this study was to identify patients at high risk of peritoneal relapse in a prospective study based on molecular prediction.Methods
RNA samples from 141 primary gastric cancer tissues after curative surgery were profiled using oligonucleotide microarrays covering 30,000 human probes. Firstly, we constructed a molecular prediction system and validated its robustness and prognostic validity by 500 times multiple validation by repeated random sampling in a retrospective set of 56 (38 relapse-free and 18 peritoneal-relapse) patients. Secondly, we applied this prediction to 85 patients of the prospective set to assess predictive accuracy and prognostic validity.Results
In the retrospective phase, repeated random validation yielded ~68% predictive accuracy and a 22-gene expression profile associated with peritoneal relapse was identified. The prediction system identified patients with poor prognosis. In the prospective phase, the molecular prediction yielded 76.9% overall accuracy. Kaplan–Meier analysis of peritoneal-relapse-free survival showed a significant difference between the “good signature group” and “poor signature group” (log-rank p = 0.0017). Multivariate analysis by Cox regression hazards model identified the molecular prediction as the only independent prognostic factor for peritoneal relapse.Conclusions
Gene expression profile inherent to primary gastric cancer tissues can be useful in prospective prediction of peritoneal relapse after curative surgery, potentially allowing individualized postoperative management to improve the prognosis of patients with advanced gastric cancer. 相似文献89.
Kolev Y Uetake H Iida S Ishikawa T Kawano T Sugihara K 《Annals of surgical oncology》2007,14(10):2738-2747
Background Many studies have shown that angiogenesis plays an important role in the process of cancer development and progression. Vascular
endothelial growth factor (VEGF) has a potent angiogenic activity, and cyclooxygenase-2 (COX-2) supports angiogenesis by regulated
production of angiogenic factors, including VEGF. The purpose of this study was to examine the expression of VEGF in combination
with COX-2 and CD34, their correlation with various clinicopathological factors, and their prognostic significance in human
gastric carcinoma.
Methods Specimens from 169 patients with different grade and stage gastric carcinoma were investigated by immunohistochemistry for
COX-2 and VEGF expression. Tumor microvessel density was assessed with CD34 immunostaining. Correlations between the expression
of VEGF, COX-2, CD34, and various clinicopathological factors were studied. The effect of these proteins on patient survival
was determined.
Results COX-2 and VEGF were positively expressed in 36.7% and 50.3% of the patients, respectively. Positive correlation was found
between VEGF and COX-2 and between VEGF and CD34. VEGF expression was correlated with depth of invasion; metastatic lymph
nodes; lymphatic and venous invasion; and tumor, node, metastasis system stage. Patients with positive staining for VEGF showed
far lower disease-free (64.9% vs. 81.3%) and overall (58.3% vs. 76.9%) survival rates than VEGF-negative patients. In multivariate
analysis, only tumor location, depth of invasion, and lymph node metastasis were shown to be independent prognostic factors.
Conclusions VEGF expression correlates with angiogenesis and tumor progression and is a valuable prognostic factor in patients with gastric
carcinoma. 相似文献
90.
Background We investigated factors affecting 5-year survival in patients undergoing hepatic resection for colorectal cancer metastases,
including events long after initial hepatectomy. Although retrospective studies have demonstrated survival benefit of hepatectomy
for metastatic colorectal cancer, few have included sufficient 5-year survivors to identify survival-related factors throughout
the clinical course.
Methods We divided 156 patients with hepatectomy for colorectal cancer metastases into 5-year survivors (n = 64) and patients dying
before 5 years after hepatectomy (n = 92). Clinicopathologic data were compared retrospectively with respect to long-term
outcome.
Results By multivariate analysis, large liver tumors (adjusted relative risk, 2.029; P = .011), short tumor doubling time (1.809; P = .026), and origin from poorly differentiated primary adenocarcinoma (12.632; P = .001) compromised survival, whereas initial treatment-related variables did not. Although no difference was seen in initial
treatment-related variables between 5-year survivors with recurrence after hepatectomy and patients dying before 5 years,
repeat surgery was used more frequently in survivors (P < .001), typically with adjuvant chemotherapy.
Conclusions Reoperations for each recurrence of metastases, followed by additional chemotherapy, frequently resulted in long survival. 相似文献