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Colloidal crystals (CCs) are periodic arrays of monodisperse microparticles. Such CCs are very attractive as they can be potentially applicable as versatile photonic devices such as reflective displays, sensors, lasers, and so forth. In this article, we describe a promising methodology for synthesizing monodisperse magnetite microparticles whose diameters are controllable in the range of 100–200 nm only by adjusting the base concentration of the reaction solution. Moreover, monodisperse magnetite microparticles in aqueous suspensions spontaneously form the CC structures under an external magnetic field, leading to the appearance of Bragg reflection colors. The reflection peak can be blue-shifted from 730 nm to 570 nm by the increase in the external magnetic field from 28 mT to 220 mT. Moreover, the reflection properties of CCs in suspension depend on the microparticle concentration in suspension and the diameter of the magnetite microparticles. Both fine-control of microparticle diameter and investigation of magneto-optical properties of CCs would contribute to the technological developments in full-color reflective displays and sensors by utilizing these monodisperse magnetite microparticles.  相似文献   
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One and a half ventricle repair for Ebstein’s anomaly   总被引:2,自引:0,他引:2  
The surgical strategy for patients having Ebstein’s anomaly and hypoplastic right ventricle is controversial. An 11-year-old boy patient having such condition, with estimated end-diastolic volume index of the atrialized and functional right ventricle being 70% of normally expected values, underwent biventricular repair. Immediately after the surgery, however, he developed right heart failure with the central venous pressure of 11 mmHg. He consequently underwent additional bidirectional cavopulmonary anastomosis, thereby converting the biventricular repair into one and a half ventricle repair. He recovered uneventfully and is doing well 2 years after the surgery.  相似文献   
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We report an extremely rare case of a gastric duplication cyst together with an aberrant pancreatic ductal system, which communicated with the stomach rather than the pancreatic ductal system with no evidence of pancreatitis. A 46-year-old woman developed severe abdominal pain after a 10-year history of occasional mild abdominal pain. Upper gastrointestinal barium radiography showed a rigidity of the stomach wall, and gastroscopy revealed a fistula orifice at a greater curvature of the gastric body. Subsequent endoscopic suction of mucous secretion from within the fistula provided immediate pain relief. Abdominal computed tomography and ultrasonography showed a cystic mass contiguous with the stomach wall. Surgical exploration revealed an uncommon anomaly of a gastric duplication cyst with the aberrant pancreatic lobe. The patient made an uneventful recovery and remains well 4 years after surgery. We also herein review ten other similar cases of this uncommon congenital anomaly reported in the literature. Received: August 20, 2001 / Accepted: January 8, 2002  相似文献   
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A 73-year-old man on dialysis for chronic renal dysfunction was referred to our hospital for surgical treatment of an abdominal aortic aneurysm (AAA). Preoperative angiography showed a remarkably developed meandering artery branching from the inferior mesenteric artery (IMA). The superior mesenteric and celiac arteries were occluded at the origin, and all blood flow to the abdominal organs was apparently supplied by collateral circulation from the IMA. Considering the risk of mesenteric ischemia after aortic clamping in conjunction during surgery, we used a perfusion catheter with a 12-F balloon to create a shunt to the IMA from the subclavian artery. The operation was successful and the patient recovered uneventfully. We describe this surgical procedure for its effectiveness in preventing postoperative mesenteric ischemia in a rare case of an AAA with complex branching lesions.  相似文献   
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OBJECTIVE: A joint study was undertaken by the Japanese Society of Renal Cancer to investigate the present status of partial nephrectomy in Japan and to speculate about what may be the indications for partial nephrectomy in patients with renal cell carcinoma. METHODS: Data were tabulated for 469 patients from participating medical institutions and various clinical factors were investigated with regard to disease progression (local recurrence and distant metastasis). RESULTS: Disease progression was observed in 21 patients (4.5%). No significant relation to disease progression was observed for sex, laterality, tumor histology, grade and tumor size. Although patients with solitary tumors displayed excellent prognosis irrespective of tumor diameter, patients with multiple tumors displayed a high likelihood of disease progression. Patients older than 77 years old and patients with imperative indication were found to have a poorer prognosis. CONCLUSION: In patients with solitary tumors, partial nephrectomy can be actively performed, even if the patient displays elective indications and the tumor is >4 cm in diameter. In patients displaying multiple tumors with imperative indications, the decision whether to perform partial nephrectomy should be made by the patients and their physicians after considering the impact on curability and the quality of life.  相似文献   
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Ischemia/reperfusion injuries are a major problem in liver resections and transplantations. Tumor necrosis factor-alpha has been widely investigated as a key mediator in the mechanism of ischemia/reperfusion injury. Upstream signal transduction mechanisms for tumor necrosis factor-alpha have not been well documented. Therefore, we assessed c-Jun N-terminal kinase activation during warm hepatic ischemia/reperfusion injuries in a rat model. Male Wistar rats were subjected to 30 minutes of ischemia followed by reperfusion. Hepatic enzymes, histological examinations, microfluorographs, and tumor necrosis factor-alpha protein production (in the serum and liver tissue) were analyzed during the course of reperfusion. c-Jun N-terminal kinase activity was measured by a radioisotope kinase assay. Ischemia/reperfusion injuries were characterized by an elevation in hepatic enzyme, the histological degeneration of hepatocytes, and an increase in the number of nonviable cells. Moreover, increased endothelial-adherent leukocytes and tumor necrosis factor-alpha protein production were also observed. c-Jun N-terminal kinase activity at 60 minutes after reperfusion was 12.4 times higher than the pre-ischemia level. These results suggest that c-Jun N-terminal kinase may play some role in the mechanism of ischemia/reperfusion injuries.  相似文献   
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Background  

Surgical trauma may be associated with enhanced tumor growth and establishment. The authors studied the effect of carbon dioxide (CO2) pneumoperitoneum versus laparotomy on tumor necrosis factor-α (TNFα), migration inhibitory factor (MIF) expression, and nuclear factor kappa B (NFκB) activity in human gastric cancer.  相似文献   
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