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941.
Thioredoxin (TRX) is a redox-regulating protein, induced in response to oxidative stress. The function of TRX in the urine is unknown. We show here that urinary TRX begin to increase within one hour and peaks within two hours after ischemia reperfusion of mice. Serum levels of TRX are not changed by the ischemia/reperfusion. In a time-dependent study of immunohistochemistry, TRX appears diffusely in the tubular cytosol in sham-operated mice. On the other hand, immediately after renal ischemia/reperfusion, TRX become to eccentrically-locate in the apical side of the tubular cytosol, and then TRX is detected only in the urinary lumen. In contrast, when we examine the immunolocalization of glutaredoxin, which is a member of the TRX superfamily, we find that the immunoreactivity is unchanged after renal ischemia/reperfusion. Northern blotting and in situ hybridization show that epithelial cells constitutively express TRX mRNA but neither expression levels nor distribution are altered by ischemia-reperfusion. An overexpression of hTRX in transgenic mice attenuates the reperfusion injury. These data suggests that TRX is produced in tubular cells in a steady state. The increase in the urine after ischemia-reperfusion is not mediated by a de novo induction of TRX mRNA but by a discharge of TRX protein from tubular epithelial cells. TRX is useful for the diagnosis of AKI in association with oxidative stress.  相似文献   
942.
943.
Previous research and theory (Crocker & Wolfe, 2001; Kernis, 2003) suggests that adaptive self-esteem stems from just being oneself, and is characterized by a sense of authenticity (SOA). Maladaptive self-esteem is derived from meeting external standards and social comparisons, and is characterized by a sense of superiority (SOS). Thus, the qualitative difference between SOA and SOS depends on the sources of self-esteem. We hypothesized that SOA is related to internal sources of self-esteem, while SOS is related to external sources. In order to control for covariance, global self-esteem was also examined in a questionnaire survey of self-esteem that was administered to 273 university students. The results of a partial correlation analysis showed that SOA was positively correlated with internal sources of self-esteem such as committed activities and efforts for self-development. In contrast, SOS was positively correlated with external sources of self-esteem such as approval from others and appearance. These results mainly support our hypotheses.  相似文献   
944.
In the real-time tumor-tracking radiotherapy system, fluoroscopy is used to determine the real-time position of internal fiducial markers. The pattern recognition score (PRS) ranging from 0 to 100 is computed by a template pattern matching technique in order to determine the marker position on the fluoroscopic image. The PRS depends on the quality of the fluoroscopic image. However, the fluoroscopy parameters such as tube voltage, current and exposure duration are selected manually and empirically in the clinical situation. This may result in an unnecessary imaging dose from the fluoroscopy or loss of the marker because of too much or insufficient x-ray exposure. In this study, a novel optimization method is proposed in order to minimize the fluoroscopic dose while keeping the image quality usable for marker tracking. The PRS can be predicted in a region where the marker appears to move in the fluoroscopic image by the proposed method. The predicted PRS can be utilized to judge whether the marker can be tracked with accuracy. In this paper, experiments were performed to show the feasibility of the PRS prediction method under various conditions. The predicted PRS showed good agreement with the measured PRS. The root mean square error between the predicted PRS and the measured PRS was within 1.44. An experiment using a motion controller and an anthropomorphic chest phantom was also performed in order to imitate a clinical fluoroscopy situation. The result shows that the proposed prediction method is expected to be applicable in a real clinical situation.  相似文献   
945.
A celiomesenteric trunk (CMT) accounts for fewer than 1% of all visceral artery anomalies. Aneurysms involving a CMT are exceptionally rare: our search of the literature found only eight cases reported. We treated a 73-year-old man with both a fusiform CMT aneurysm and an abdominal aortic aneurysm (AAA). The celiac artery and superior mesenteric artery were reconstructed by performing a retrograde prosthetic-graft bypass originating from the right limb of the bifurcated aortic graft used to repair the AAA. To our knowledge, this is the first report of successful surgical treatment of a CMT aneurysm and coexistent AAA.  相似文献   
946.
Endoscopists seek to conduct more aggressive surgical procedures that surpass the limitations of existing endoscopic procedures. Endoscopic pancreatic necrosectomy and natural orifice transluminal endoscopic surgery (NOTES) are typical examples of this new trend; both are performed through the gastrointestinal wall without a skin incision. Endoscopic necrosectomy is effective for managing organized pancreatic necrosis and abscesses. The necrotic tissues are removed endoscopically by directly entering the cavity of the organized pancreatic necrosis. NOTES is a possible advance over surgical intervention, as it is a less invasive, more cosmetic, and effective procedure. There are various approaches, including the esophagus, stomach, colon, and vagina; Various procedures are possible using NOTES, such as cholecystectomy, appendectomy, full-thickness stomach resection, splenectomy, gastrointestinal (GI) anastomosis, and peritoneoscopy. The requirements for NOTES include high proficiency in endoscopic techniques, including knowledge of various devices, anatomy, and surgical procedures. Since most GI endoscopists have no surgical background, to increase the usage of NOTES, GI endoscopists should form and lead teams that include various specialists. We believe that endoscopic necrosectomy and NOTES represent a major shift in the treatment paradigm because physicians can treat beyond the gastrointestinal wall and endoscopic procedures will replace surgical treatment.  相似文献   
947.
Background/Purpose  We aimed to clarify the association between the presence of micrometastases around liver metastases from gastric cancer and the results of hepatic resection. In addition, we investigated the influence of E-cadherin and matrix metalloproteinase (MMP)-7 expression on the development of micrometastases. Methods  Micrometastases around liver metastases were examined microscopically in 31 metastatic liver tumor specimens resected from 17 patients who had undergone hepatic resection for liver metastases from gastric cancer. E-cadherin and MMP-7 expression in the primary gastric tumor, the liver metastases, and the micrometastases were examined immunohistochemically. Results  Hepatic micrometastases were present in around 48% of the liver metastases, accounting for 59% of the patients. The tumor recurrence rate in the remnant liver after hepatic resection was significantly higher, and survival significantly poorer, in patients with such micrometastases than in those without. Micrometastases tended to appear around the liver metastases that had reduced E-cadherin expression. Most of the micrometastases in the lymph ducts and sinusoids showed reduced E-cadherin expression. MMP-7 expression was not correlated with the presence of micrometastases. Conclusions  About half of the hepatic metastases from gastric cancer had seeded off micrometastases, and the presence of these micrometastases was associated with a poorer result of hepatic resection. Reduced E-cadherin expression in metastatic liver tumors may be associated with the development of micrometastases.  相似文献   
948.
Background  Few studies of treatment of lateral ankle ligament rupture have given careful consideration to the activity levels of patients. In the present study, we investigated whether a patient’s activity level influences the outcome of the treatment of lateral ankle ligament rupture and whether treatment should be determined according to activity level. Methods  A total of 115 consecutive patients with lateral ankle ligament rupture were treated with short-term cast immobilization followed by functional bracing. We divided preinjury activity levels and activity levels at follow-up into four classes according to the International Knee Documentation Committee standards. Follow-up examination 1 year after injury included clinical assessment (anterior drawer test, range of motion, maximum circumference of the calf, tenderness, swelling), reinjury assessment, and functional evaluation by means of the Karlsson scoring system. Results  We found significant differences in ankle stability and reinjuries between the four groups classified by their preinjury activity level. The number of patients with ankle instability and reinjury was significantly higher in the high-activity group than in the low-activity groups. We also found significant difference between groups classified by activity level at follow-up with regard to the Karlsson score. Conclusions  The outcome of treatment of lateral ankle ligament rupture is significantly influenced by the patient activity level, and treatment may need to be determined according to this activity level.  相似文献   
949.
950.
A 4-year-old girl with a congenital choledochal cyst (Todani IV-A, Komi type A) underwent a resection of the dilated common bile duct and gallbladder. Histologic studies of the gallbladder showed a general hyperplastic change associated with cribriform proliferation at the gland base of the gallbladder. In this region, clusters of cribriform glands were found within the lymphatic vessels, compatible with lymphatic infiltration of tumor cells. However, careful histologic studies did not reveal any apparent neoplastic changes in the gallbladder and common bile duct, so a final diagnosis of epithelial atypism with reactive hypertrophy was made. The displacements observed in the lymphatics are just an incidental finding in a proliferative process of the hyperplastic gallbladder epithelium. In the follow-up observation for 3 years, the patient is doing well without evidence of tumor recurrence. These results suggest that a mere lymphatic infiltration of hyperplastic gallbladder epithelium should not be directly considered as evidence of carcinogenesis.  相似文献   
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