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排序方式: 共有3918条查询结果,搜索用时 45 毫秒
31.
Hitoshi Matsuda Masayoshi Okada Chojiro Yamashita Takaki Sugimoto Yoshihisa Watanabe 《General thoracic and cardiovascular surgery》1999,47(5):234-236
A 59-year-old man with a history of the thoraco-abdominal esophagus resection with retrosternal gastric tube reconstruction for esophageal cancer complicated by anastomosis leakage and purulent pericarditis was admitted for aortic regurgitation due to infective endocarditis. Floppy vegetation and worsening cardiac failure indicated aortic valve replacement. In a median sternotomy approach, the thickest adhesion between the cervical esophagus and posterior surface of the manubrium sternae was freed using an ultrasonic osteotome. Severe adhesions in the pericardium due to purulent pericarditis were found. Median sternotomy enabled minimal exposure of the aortic root, upper right atrium, and right superior pulmonary vein for instituting extracorporeal circulation and replacing the aortic valve. The patient’s postoperative course was uneventful. For cardiac surgery in patients with a retrosternal gastric tube, left anterior or right thoracotomy may be considered to avoid gastric tube injury. Median sternotomy, however, is an alternative enabling safe heart exposure, and the ultrasonic osteotome was very useful in incising the sternum without injuring the cervical esophagus, which had no serosa. 相似文献
32.
Masayoshi Ozawa Kimiharu Iwadate Sari Matsumoto Kumiko Asakura Eriko Ochiai Kyoko Maebashi 《Legal medicine (Tokyo, Japan)》2013,15(6):293-297
Rigor mortis is an important phenomenon to estimate the postmortem interval in forensic medicine. Rigor mortis is affected by temperature. We measured stiffness of rat muscles using a liquid paraffin model to monitor the mechanical aspects of rigor mortis at five temperatures (37, 25, 10, 5 and 0 °C). At 37, 25 and 10 °C, the progression of stiffness was slower in cooler conditions. At 5 and 0 °C, the muscle stiffness increased immediately after the muscles were soaked in cooled liquid paraffin and then muscles gradually became rigid without going through a relaxed state. This phenomenon suggests that it is important to be careful when estimating the postmortem interval in cold seasons. 相似文献
33.
Hideki Kawai Sadako Motoyama Masayoshi Sarai Yukio Ozaki 《Journal of Cardiovascular Computed Tomography》2013,7(6):417-418
An 80-year-old asymptomatic man presented with ST-segment elevation in leads V1 to V5. Coronary CT angiography showed that microfistulae arising from multiple arteries may have led to myocardial infarction from intracoronary thromboembolism within the dilated left anterior descending (LAD). 相似文献
34.
Non-viral in vivo thrombomodulin gene transfer prevents early loss of thromboresistance of grafted veins. 总被引:1,自引:0,他引:1
Noriyuki Tabuchi Masayoshi Shichiri Aya Shibamiya Takatoshi Koyama Fumie Nakazawa Jihwa Chung Shinsaku Hirosawa Makoto Sunamori 《European journal of cardio-thoracic surgery》2004,26(5):995-1001
OBJECTIVE: Immediate loss of thrombomodulin activity in the endothelium of vein grafts has been demonstrated during 90 min exposure to arterial circulation; this loss of activity is ascribed as an important cause of early thrombosis. Conventional ex vivo gene transfection after vein harvest cannot cover this acute period immediately after implantation. We have established a highly efficient non-viral gene therapy protocol utilizing modified transferrin receptor-facilitated gene transfer. Using this technique, we examined whether in vivo thrombomodulin gene therapy, directed to the endothelium of rat veins 2 days prior to grafting, may prevent thromboresistance impairment of vein grafts under simulated arterial circulation. METHODS: Abdomen of SD rat was opened and cationic liposome:transferrin:thrombomodulin gene complexes or the vector without DNAs were applied to the inferior vena cava of rats while blood flow was reduced by proximal and distal clamping. After 2 days, the transfected veins were harvested and thrombomodulin expression and thromboresistance properties determined before and after exposure to an artificial circuit. RESULTS: The trial of gene transfection using variable doses of DNAs confirmed that 7.5 microg of total DNAs was the most efficient quantity for thrombomodulin gene transfection to IVCs, although accompanying an increase of gene expression in other downstream organs. By transfection of the thrombomodulin gene in IVCs, the generation capacity of activated protein C in venous endothelium increased three-fold compared with veins treated with vector alone (P<0.01). Under simulated arterial circulation, perfusion of veins treated with vector alone decreased thrombomodulin activity to 36% of preperfused levels (P<0.01), whereas transfected grafts preserved the activity at normal vein endothelium levels even after perfusion. Consequently, the increase in endothelial thrombin activity induced by simulated arterial circulation was markedly attenuated in transfected veins (P<0.01), while immunohistochemistry confirmed the preservation of endothelial lining. CONCLUSIONS: Transferrin receptor-facilitated in vivo gene transfer to the inferior vena cava resulted in sufficient thrombomodulin gene expression immediately after graft implantation and subsequent maintenance of thromboresistance even after exposure to arterial pressure. Although further studies are needed, the present results suggest the possibility of gene therapy targeting acute phases of vein graft disease. 相似文献
35.
Morimae H Maekawa T Tamai H Takahashi N Ihara T Hori A Narita H Banno H Kobayashi M Yamamoto K Komori K 《Surgery today》2012,42(2):121-126
Purpose
We conducted this study to compare the cost of open surgical repair (OR) with that of endovascular aneurysm repair (EVAR) of an abdominal aortic aneurysm (AAA).Methods
Between January 2007 and November 2008, 70 patients underwent open repair and 57 patients underwent EVAR. We evaluated the total cost, including that of the Diagnosis Procedure Combination (DPC), that of the surgical procedure, that of materials such as grafts and guide wires, and that of the anesthesia.Results
The mean costs for OR versus EVAR were as follows: DPC, ??632370 versus ??490050, respectively, which was significant; anesthesia, ??123540 versus ??86220, respectively (P?0.05); and materials, ??257770 versus ??2113280, respectively (P?0.05). Thus, the mean total cost was ??1825830 versus ??3159270 for open repair and EVAR, respectively (P?0.05).Conclusions
New technologies should not only be clinically effective, but also cost effective. EVAR is less invasive clinically, but the cost of endovascular prostheses and other materials remains high. 相似文献36.
Ryoichi Imamura Yoshitaka Isaka Ruben M. Sandoval Naotsugu Ichimaru Toyofumi Abe Masayoshi Okumi Koji Yazawa Harumi Kitamura Jyunya Kaimori Norio Nonomura Hiromi Rakugi Bruce A. Molitoris Shiro Takahara 《Clinical and experimental nephrology》2012,16(6):852-862
Background
The tissue-protective effects of erythropoietin (EPO) have been extensively investigated, and EPO administration can raise the hemoglobin (Hb) concentration. Recently, we reported that carbamylated erythropoietin (CEPO) protected kidneys from ischemia-reperfusion injury as well as EPO.Methods
To investigate the clinical applications of CEPO, we next evaluated the long-term therapeutic effect of CEPO using a tubulointerstitial model rat. We randomized remnant kidney model rats to receive saline, EPO, or CEPO for 8?weeks.Results
CEPO- and EPO-treated rats had improved serum creatinine levels compared with saline-treated remnant kidney model rats, although the Hb level was significantly increased in EPO-treated rats. Two-photon microscopy revealed that EPO/CEPO significantly ameliorated tubular epithelial cell damage assessed by endocytosis. In addition, CEPO or EPO protected endothelial cells with a sustained blood flow rate. EPO or CEPO suppressed the number of TUNEL-positive apoptotic cells with weak ??SMA staining. Furthermore, PCR analysis demonstrated that TGF-?? and type I collagen expression was attenuated in EPO- or CEPO-treated rats, accompanied by a significant decrease in interstitial fibrosis.Conclusion
We established a long-term therapeutic approach to protect tubulointerstitial injury with CEPO, and thus, the therapeutic value of this approach warrants further attention and preclinical studies. 相似文献37.
Ranalletta M Jiang H Li J Tsao TS Stenbit AE Yokoyama M Katz EB Charron MJ 《Diabetes》2005,54(4):935-943
Studies were conducted to explore altered substrate utilization and metabolism in GLUT4 null mice. Liver fatty acid synthase mRNA and fatty acid synthesis rates were dramatically increased in GLUT4 null mice compared with control mice and were supported by increased rates of the pentose phosphate pathway oxidative phase and sterol regulatory binding protein mRNA expression. Increased GLUT2 protein content, glucokinase mRNA, and glucose-6-phosphate in GLUT4 null mice may provide substrate for the enhanced fatty acid synthesis. Increased fatty acid synthesis, however, did not lead to hepatic triglyceride accumulation in GLUT4 null mice because of increased hepatic triglyceride secretion rates. GLUT4 null mice rapidly cleared orally administered olive oil, had reduced serum triglyceride concentrations in the fed and the fasted state, and increased skeletal muscle lipoprotein lipase when compared with controls. Oleate oxidation rates were increased in GLUT4 null skeletal muscle in association with mitochondrial hyperplasia/hypertrophy. This study demonstrated that GLUT4 null mice had increased hepatic glucose uptake and conversion into triglyceride for subsequent use by muscle. The ability of GLUT4 null mice to alter hepatic carbohydrate and lipid metabolism to provide proper nutrients for peripheral tissues may explain (in part) their ability to resist diabetes when fed a normal diet. 相似文献
38.
Role of positive selection of thymoma-associated T cells in the pathogenesis of myasthenia gravis 总被引:3,自引:0,他引:3
Inada K Okumura M Shiono H Inoue M Kadota Y Ohta M Matsuda H 《The Journal of surgical research》2005,126(1):34-40
BACKGROUND: A human thymoma is a thymic epithelial neoplasm and is characterized by its frequent association with myasthenia gravis. The histological characteristic of thymoma is coexistence of a large number of lymphocytes, including CD4(+)CD8(+) double positive T cells, phenotypes of the cortical thymocytes. To elucidate the role of these T lymphocytes in the pathogenesis of thymoma-associated myasthenia gravis, we examined the usage of alphabeta or gammadelta T cell receptor of the T lymphocytes in thymoma in conjunction with the positive selection event. MATERIALS AND METHODS: Thymomas were obtained from 28 patients. Nine patients were associated with myasthenia gravis. Lymphocytes were freshly isolated from the tumor tissue and were subjected to four-color flow cytometric analysis. RESULTS: The average proportion of TCRalphabeta(+) cells in thymomas associated with myasthenia gravis was 47.0% and was significantly higher (P = 0.0008) than that without myasthenia gravis (23.4%). Positive selection event was then examined in terms of CD69, a positive selection marker. The mean proportion of TCRalphabeta(+)CD69(+)CD4(+)CD8(-) cells in the myasthenic thymomas (8.22%) was significantly greater (P = 0.015) than the nonmyasthenic thymomas (2.99%). On the other hand, there was not a significant difference in the mean proportion of TCRalphabeta(+)CD69(+)CD4(-)CD8(+) cells between the myasthenic and the nonmyasthenic thymomas. CONCLUSIONS: The possible role of development of TCRalphabeta(+) T cells, especially the role of positive selection of TCRalphabeta(+)CD4(+)CD8(-) T cells in thymoma, was suggested in the pathogenesis of thymoma-associated myasthenia gravis. 相似文献
39.
Intraductal papillary mucinous tumor of the pancreas associated with autosomal dominant polycystic kidney disease 总被引:1,自引:0,他引:1
Hiroshi Naitoh M.D. Hisanori Shoji M.D. Isao Ishikawa M.D. Reina Watanabe M.D. Yuichi Furuta M.D. Shigeru Tomozawa M.D. Hiroaki Igarashi M.D. Sachiko Shinozaki M.D. Hideyuki Katsura M.D. Ryoichi Onozato M.D. Masayoshi Kudoh M.D. 《Journal of gastrointestinal surgery》2005,9(6):843-845
A 43-year-old male with a history of autosomal dominant polycystic kidney disease (ADPKD) was admitted to our center with severe abdominal pain and was diagnosed with acute pancreatitis. CT showed multiple cysts in the liver and both kidneys along with ADPKD and a cystic mass, 4 cm in diameter, in the pancreatic head. The main pancreatic duct was dilated to 1 cm in diameter. The patient was diagnosed with acute pancreatitis due to intraductal papillary mucinous tumor (IPMT), and pancreatoduodenectomy was performed. Histologic examination revealed a multiloculated cystic tumor filled with mucin in the head of the pancreas. Microscopically, the tumor was diagnosed as adenocarcinoma and was found to have invaded the main pancreatic duct. Although, in addition to our case, only seven cases with association between ADPKD and malignant neoplasms have been reported, five of these cases had neoplasms arising from the pancreas. Therefore, we suggest that some genetic interactions may exist between ADPKD and pancreatic carcinogenesis. 相似文献
40.
Sugimoto T Kume S Osawa N Isshiki K Kanasaki K Tanaka Y Chin M Shibuya K Sakaguchi M Araki S Isono M Koya D 《Nihon Jinzo Gakkai shi》2005,47(4):463-467
A 31-year-old man was admitted to the hospital because of a low-grade fever, general malaise, nausea, vomiting, and a poor appetite. On admission his renal function was severely deteriorated (serum creatinine 16.12 mg/dl, BUN 163 mg/dl), and he had severe anemia (Hb 7.5 g/dl) and thrombocytopenia (67,000/microl). A radiological examination revealed the presence of multiple cysts in his kidneys bilaterally. The patient was diagnosed as having end-stage renal disease due to polycystic kidney disease, and hemodialysis was started on the day of admission. After the initiation of hemodialysis, his symptoms and laboratory tests improved, except for anemia and thrombocytopenia. He was noted to have marked splenomegaly and dilation of the portal vein, raising the suspicion of portal hypertension as the cause of the splenomegaly and pancytopenia. To treat his pancytopenia (anemia and thrombocytopenia) and to determine the reason for his portal hypertension, a splenectomy and open-wedge biopsy of the liver were performed. Histological findings in the liver included extensive fibrosis of the portal areas with an excess of moderately dilated bile ducts, compatible with a diagnosis of congenital hepatic fibrosis. After splenectomy, his red blood cell and platelet counts returned to normal, and he was discharged on maintenance dialysis. Congenital hepatic fibrosis is often associated with autosomal recessive polycystic kidney disease (ARPKD), but not with autosomal dominant polycystic kidney disease (ADPKD). However, both his mother and older brother had multiple renal cysts, indicating that this was an unusual case of ADPKD complicated by congenital hepatic fibrosis. 相似文献