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81.
Clinical evaluation of a bioluminescent enzyme immunoassay for detecting norovirus in fecal specimens from patients with acute gastroenteritis
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82.
83.
Continuation of antithrombotic therapy may be associated with a high incidence of colonic post‐polypectomy bleeding
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Tomoyoshi Shibuya Osamu Nomura Tomohiro Kodani Takashi Murakami Hirofumi Fukushima Yuzuru Tajima Kohei Matsumoto Hideaki Ritsuno Hiroya Ueyama Yoshihiro Inami Dai Ishikawa Kenshi Matsumoto Naoto Sakamoto Taro Osada Akihito Nagahara Tatsuo Ogihara Sumio Watanabe 《Digestive endoscopy》2017,29(3):314-321
84.
Renal, adrenal, gonadal, ureteral and inferior phrenic arteries vary in their level of origin and in their calibre, number and precise anatomical relationship to other structures. Studies of the origin and early development of these arteries have evoked sharp disputes. The ladder theory of Felix, which states that ‘All the mesonephric arteries may persist; from them are formed the phrenic, suprarenal, renal and internal spermatic arteries’ has been generally quoted in the anatomical textbooks without rigorous verification for 100 years. In this study, we re-examined this theory by performing micro-injection of dye and resin into rat (Rattus norvegicus) embryos. Our results revealed that most of the mesonephric arteries had degenerated before the metanephros started its ascent. The definitive renal, adrenal, gonadal, ureteral and inferior phrenic arteries appeared as new branches from the gonadal artery and/or directly from the abdominal aorta to the para-aortic ridge. Coincidental to this, the anatomical architecture of the inter-renal vascular cage, which consists of the interlobar and arcuate arteries and their collateral veins, was completed within the developing metanephros. We demonstrated that the delicate renal vascular cage switched from the primary renal artery to the definitive renal artery and that the route of venous drainage changed from the posterior cardinal vein to the inferior (caudal) vena cava. 相似文献
85.
Taiji Takahashi Michiro Otaka Masaru Odashima Kumiko Tamaki Makiko Takada Yuko Izumi Tomoyoshi Shibuya Naoto Sakamoto Hideaki Itoh Sumio Watanabe 《Journal of Clinical Biochemistry and Nutrition》2010,47(1):64-73
Recent studies have indicated that heat shock proteins (HSPs), which function as molecular chaperones, play important roles in cellular responses to stress-related events. However, the gender difference in the expression of HSP in the gastric mucosa remains unclear. In order to understand the mechanism of gender difference in the prevalence or severity of gastric mucosal lesions, the expression level of HSP and the correlation of estrogen to HSP induction in the gastric mucosa were evaluated in this study. The basal expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. The gastric ulcer index was significantly higher in male rats compared to female rats observed after 12 h water immersion stress exposure. At this time point, the expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. An estrogen-treatment significantly induced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Inversely, an ovariectomy dramatically reduced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Our results suggested that estrogen might play an important role in gastric mucosal protection with the induction of gastric mucosal HSPs. 相似文献
86.
Takehiro Kukitsu Tetsuji Takayama Koji Miyanishi Atsushi Nobuoka Shinichi Katsuki Yasushi Sato Rishu Takimoto Takuya Matsunaga Junji Kato Tomoko Sonoda Sumio Sakamaki Yoshiro Niitsu 《Clinical cancer research》2008,14(1):48-54
PURPOSE: Long-standing ulcerative colitis (UC) predisposes patients to the development of colorectal cancer, but surveillance of colitis-associated cancer by detecting the precancerous lesion dysplasia is often difficult because of its rare occurrence and normal-looking appearance. In sporadic colorectal cancer, aberrant crypt foci (ACF) have been reported by many investigators to be precursor lesions of the adenoma-carcinoma sequence. In the present study, we analyzed the genetic background of ACF to determine whether they could be precursors for dysplasia, and we examined the usefulness of endoscopic examination of ACF as a surrogate marker for surveillance of colitis-associated cancer. EXPERIMENTAL DESIGN: ACF were examined in 28 UC patients (19 patients with UC alone and 9 patients with UC and dysplasia; 2 of those patients with dysplasia also had cancer) using magnifying endoscopy. K-ras, APC, and p53 mutations were analyzed by two-step PCR RFLP, in vitro--synthesized protein assay, and single-strand conformation polymorphism, respectively. Methylation of p16 was analyzed by methylation-specific PCR. RESULTS: ACF that appeared distinct endoscopically and histologically were identified in 27 out of 28 UC patients. They were negative for K-ras, APC, and p53 mutations but were frequently positive for p16 methylation (8 of 11; 73%). In dysplasia, K-ras and APC mutations were negative but p53 mutation (3 of 5; 60%) and p16 methylation (3 of 5; 60%) were positive. There was a significant stepwise increase in the number of ACF from patients with UC alone to patients with dysplasia and to patients with cancer. Univariate and multivariate analyses showed significant correlations between ACF and dysplasia. CONCLUSIONS: We have disclosed an ACF-dysplasia-cancer sequence in colitis-associated carcinogenesis similar to the ACF-adenoma-carcinoma sequence in sporadic colon carcinogenesis. This study suggests the use of ACF instead of dysplasia for the surveillance of colitis cancer and warrants further evaluation of ACF as a surveillance marker in large-scale studies. 相似文献
87.
Yamamoto Satoshi; Mitsumori Kunitoshi; Kodama Yukio; Matsunuma Naochika; Manabe Sunao; Okamiya Hideaki; Suzuki Hiroshi; Fukuda Tatsuya; Sakamaki Yoshiyuki; Sunaga Masao; Nomura Gakushi; Hioki Kyoji; Wakana Shigeharu; Nomura Tatsuji; Hayashi Yuzo 《Carcinogenesis》1996,17(11):2455-2461
In this study, we investigated the carcinogenic response oftransgenic mice carrying the human prototype c-Ha-ras gene,namely Tg rasH2/CB6F1 mice, to various genotoxic carcinogensand compared it with that of control non-transgenic CB6F1 mice(non-Tg mice). The present studies were conducted as the firststep in the evaluation of the Tg rasH2/CB6F1 mouse as a modelfor the rapid carcinogenicity testing system. Short-term ( 相似文献
88.
We treated two children with neuroblastoma and during the course of chemotherapy, avascular necrosis of the femoral head occurred. The main pathogenetic factor of this necrosis may be the toxic effect of cyclophosphamide.Abbreviations VMA
vanillylmandelic acid
- HVA
homovanillic acid 相似文献
89.
90.