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11.
12.
Tsuyoshi Takeda Hiroyuki Ishida Yukio Horiuchi Yasushi Nakao Yutaka Yabe 《Journal of orthopaedic science》1997,2(6):372-377
We examined radiographs of the elbows of the pitching arms of 79 professional baseball pitchers (mean age, 25.1 years; mean
duration of professional career, 4.7 years) and noted the frequency and size of spurs, bone fragments, and intra-articular
loose bodies according to site. The influence of duration of professional baseball career on these osteoarthritic changes
was also investigated. The olecranon tip was the most frequent site of spurs (62/79; 78.5%), and fragmentation of the spur
was detected in 17 joints. The frequency of spurs was also high at the medial margin of the olecranon, the tip of the coronoid
process, the medial margin of the sigmoid notch, the medial margin of the trochlea and the olecranon fossa. In 38 subjects,
spurs were observed at the distal portion of the radial notch of the ulna. However, few pitchers had osteoarthritic changes
in the humeral capitellum or radial head. Intra-articular loose bodies were detected in 4 of 79 joints (5.1%), and bone fragments
were present below the medial humeral epicondyle in 25 of 79 joints (31.6%). Osteoarthritic changes in the elbow joint appeared
to be attributable mainly to traction stress and impingement associated with extension and valgus strain. Significant osteoarthritic
changes were often found in professional pitchers whose careers exceeded 5 years. 相似文献
13.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
14.
Yuichi Sanada Kazuhiro Yoshida Hiroyuki Itoh Satoko Kunita Kazuto Jinushi Hideo Matsuura 《Journal of hepato-biliary-pancreatic sciences》2007,14(4):401-409
We report a case of groove pancreatitis (GP) associated with a true pancreatic cyst. An 81-year-old man who had suffered epigastric pain for 4 months was referred to Saisekai Kure Hospital. Computed tomography and endoscopic retrograde pancreatography showed a cystic lesion in the groove area of the pancreas. Serum amylase elevation and imaging findings suggested GP due to the cyst. Six weeks of medical treatment did not improve the clinical symptoms. Therefore, pancreatoduodenectomy was performed. Histologic examination revealed a true cyst with intraluminal necrosis, which produced a protein plug that obstructed the Santorini duct. The parenchyma surrounding the groove area showed marked fibrosis and inflammatory cell infiltration. GP due to true pancreatic cyst was diagnosed. Although GP is usually caused by overconsumption of alcohol, which leads to changes in the pancreatic juice and the ultimate blockage of pancreatic outflow, the histologic features in our patient suggest that true pancreatic cyst stands as a secondary cause of GP. 相似文献
15.
16.
Shiro Oka Shinji Tanaka Iwao Kaneko Hiroyuki Kanao Kazuaki Chayama 《Digestive endoscopy》2007,19(Z1):S30-S33
Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future. 相似文献
17.
Novel SCN5A mutation (Q55X) associated with age-dependent expression of Brugada syndrome presenting as neurally mediated syncope. 总被引:1,自引:0,他引:1
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism. 相似文献
18.
Shuro Yoshino Takayuki Matsumoto Koichi Kurahara Hiroyuki Kobayashi Mitsuo Iida Tadahiko Fuchigami 《Digestive endoscopy》2006,18(1):59-61
We present a 70‐year‐old man who had two episodes of melena during the preceding 8‐year period. He had a Dieulafoy‐like lesion in a diverticulum in the third portion of the duodenum. While emergency endoscopy revealed neither apparent blood nor clots around the diverticular orifice, there was a non‐bleeding vessel in the fundus of the diverticulum. The vessel ceased bleeding after argon plasma coagulation and, since then, the patient has not experienced bleeding. In cases of gastrointestinal bleeding of obscure origin, duodenal diverticulum should be considered as a possible source of bleeding, even when endoscopy discloses no apparent bleeding. 相似文献
19.
Clinical evaluation of a potassium nitrate dentifrice for the treatment of dentinal hypersensitivity
Toshihiko Nagata Hiroshi Ishida Hiroyuki Shinohara Seiji Nishikawa Shinji Kasahara Yoichi Wakano Shusaku Daigen Emanuel S. Troullos 《Journal of clinical periodontology》1994,21(3):217-221
Abstract The effectiveness of a 5% potassium nitrate dentifrice as a daily home treatment for dentinal hypersensitivity was evaluated in a double-blind study in 36 Japanese subjects who complained of cold and/or tactile hypersensitivity. The subjects were divided into 2 groups, with 18 being given a 5% potassium nitrate dentifrice (treated group) and the other 18 a vehicle paste (control group). Both groups were instructed to brush their teeth 2 × a day. The hypersensitivity levels of the affected teeth were assessed by 2 stimuli, one tactile and the other cold air, and by the perception of pain. The results of all 3 assessment methods indicated that the potassium nitrate dentifrice significantly decreased the level of hypersensitivity at weeks 4, 8, and 12. In the treated group, a rapid decrease of positive scores for both the cold air stimulus and the subjective symptoms appeared from week 2. Although a significant decrease of the assessment score was also observed in the control group, the reduction rate of the score was much greater in the treated group by ail 3 assessment methods at weeks 4, 8, and 12. Complete relief of subjective symptoms throughout the 12 weeks’examination was noted in 67% of the subjects in the treated group, but in only 6% in the control group. These results suggest the usefulness of a 5% potassium nitrate dentifrice in Japanese patients with dentinal hypersensitivity. 相似文献
20.
Yuko Takeyama Keiki Ogino Hiroyuki Segawa Haruo Kobayashi Taizo Uda Tatsuya Houbara 《Basic & clinical pharmacology & toxicology》1995,76(1):50-55
Abstract: The effects of zinc on the production of active oxygen species were investigated in rat neutrophils by chemilumi-nescence and spectrophotometric assays. The luminol-dependent chemiluminescence in unstimulated neutrophils showed a single peak. Zinc at concentrations lower than 0.1 mM augmented the intensity of chemiluminescence and showed a bimodal pattern, the first peak of which was inhibited by superoxide dismutase and catalase, while the second peak disappeared in the presence of catalase, but was unaffected by superoxide dismutase. At the same concentrations of zinc, O2? and H2O2 production increased, but secretion and activity of myeloperoxidase were not affected. Zinc at 0.1 mM enhanced the second peak of luminol-dependent chemiluminescence, and concomitantly O2? and H2O2 production of neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine. Homogenized neutrophils showed a bimodal pattern on induction by zinc, the second peak of which was inhibited slightly by catalase and completely by sodium azide, but was not inhibited by superoxide dismutase. Zinc-induced O2? production was inhibited by pertussis toxin, but was not significantly inhibited by a protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), or a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). These results suggest that zinc can augment luminol-dependent chemiluminescence by increasing O2? production through the classical signal transduction pathway, and by increasing H2O2 not via O2?. 相似文献