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71.
72.
A method for correctly assessing hydroxyl radical scavenging activity of antioxidative chemicals and/or biological compounds/materials was proposed. This method can simultaneously assess two factors, i.e. hydroxyl radical-scavenging and 5,5-dimethyl-2-hydroxy-1-pyrrolidine-N-oxide (hydroxyl radical adduct of 5,5-dimethyl-1-pyrroline-N-oxide)-reducing ability, as antioxidative properties. In this paper, some biologically common hydrophilic molecules, cell culture media, and rat plasma were tested. X-ray-induced hydroxyl radical can be detected using the electron paramagnetic resonance spin trapping technique. Using X-ray irradiation of the reaction mixture as the hydroxyl radical source, the true hydroxyl radical-scavenging ability of the subjected antioxidant can be assessed. In addition, the method simultaneously measures the reduction of 5,5-dimethyl-2-hydroxy-1-pyrrolidine-N-oxide, to estimate the reducing ability of the antioxidant. Biological materials, such as sugars and proteins, could abolish hydroxyl radical at the biological concentration. Ascorbic acid showed reducing ability at the biological concentration. The simultaneous assessment of hydroxyl radical-scavenging and reducing ability of antioxidants can be an informative index for antioxidants.  相似文献   
73.
Our purpose is to evaluate the diagnostic accuracy of apparent diffusion coefficient (ADC) measurement in differentiating malignant from benign uterine endometrial cavity lesions. We retrospectively evaluated 25 uterine endometrial cavity lesions in 25 female patients: endometrial carcinoma (n = 11), carcinosarcoma (n = 2), submucosal leiomyoma (n = 8), and endometrial polyp (n = 4). Diffusion-weighted images were performed at 1.5 T with b factors of 0–1,000/mm2. The region of interest was defined within the tumor on T2-weighted EPI image and then manually copied to an ADC map. Thereby, the ADC value was obtained. We compared ADC values between malignant and benign lesions using Student’s t-test. The mean and standard deviation of ADC values (×10−3 mm2/s) were as follows: endometrial carcinoma, 0.98±0.21; carcinosarcoma, 0.97±0.02; submucosal leiomyoma, 1.37±0.28; and endometrial polyp, 1.58±0.45. The ADC values differed significantly between malignant (0.98±0.19) and benign lesions (1.44±0.34) (P < 0.01). We defined malignant tumors as cases with an ADC value less than 1.15 × 10−3 mm2/s for obtaining the highest accuracy. Sensitivity, specificity, and accuracy were 84.6%, 100%, and 92%, respectively. ADC measurement can provide useful information in differentiating malignant from benign uterine endometrial cavity lesions.  相似文献   
74.
BACKGROUND: Cryopreservation is one solution to the problem of donor organ deficit. To investigate the effect of cryopreservation on tracheal allografts, we performed 2 experiments in rats. METHODS: In Experiment 1, we assessed second-set graft rejection. Two weeks after primary heterotopic transplantation (Group 1, fresh isografts; Group 2, fresh allografts from Lewis rats; and Group 3, cryopreserved allografts from Lewis rats; n = 5, respectively), each animal underwent secondary heterotopic grafting with isografts and allografts from Lewis and Wistar Furth rats (n = 5, respectively). Four weeks after the secondary transplantation, all grafts were retrieved for histologic analysis. In Experiment 2, we assessed the long-term results of allograft cryopreservation, without immunosuppression therapy. Six months after transplantation of fresh (Group 4) and cryopreserved (Group 5) allografts, the tracheal segments (each group, n = 5) were histologically evaluated. RESULTS: In Experiment 1, only the secondary allografts from Lewis rats in Group 2 did not maintain lumen structure and often showed dislocated or destroyed cartilage. Second-set graft rejection was specifically recognized in Group 2, but not in Group 1 or 3. In Experiment 2, the cryopreserved allografts appeared almost normal and lumen rigidity was preserved 6 months after transplantation. These allografts were superior to the fresh allografts in patency and in cartilage dislocation and mononuclear cell infiltration scores, but not in the viable chondrocyte ratio. CONCLUSIONS: We conclude that cryopreservation may produce successful long-term results because of its immunomodulatory effect on tracheal allografts.  相似文献   
75.
Purpose: We examined the feasibility and effectiveness of bronchial arterial infusion (BAI) as induction chemotherapy before surgery for locally advanced non-small cell lung cancer (NSCLC). Methods: Eighteen patients with locally advanced NSCLC were given BAI consisting of cis-diamminedichloroplatinum (CDDP) (50–100 mg/m2) as induction chemotherapy before surgery (induction BAI). Six patients with clinical stage IIIA cancer had bulky N2 metastatic lymph nodes, and 12 patients with clinical stage IIIB cancer had T4 disease. Results: Of the 18 patients, 12 (67%) showed a partial response to the BAI therapy. Standard pulmonary resection was performed in 5 patients, pulmonary resection with the combined resection of adjacent organs was performed in 10 patients, and pulmonary resection with carinal resection and reconstruction was performed in 3 patients. Complete resection was possible in 14 patients (78%). There were no serious BAI therapy-related complications or postoperative deaths. The 5-year survival rate of the 18 patients was 35.7% and the median survival time (MST) was 19.4 months. Survival was better when complete resection was achieved after the induction BAI, especially in patients with stage IIIB (T4) disease. Conclusion: Based on our preliminary findings, BAI with CDDP as induction chemotherapy is feasible and may be an effective therapeutic modality for locally advanced NSCLC. Received: July 26, 2001 / Accepted: March 5, 2002  相似文献   
76.

Background  

Renal prognosis and outcome of Japanese kidney donors, who have lower preoperative glomerular filtration rate (GFR) and are generally older than their counterparts abroad, have scarcely been investigated. Here, the longitudinal changes in renal function of Japanese kidney donors were studied to clarify the prevalence and consequences of low GFR.  相似文献   
77.

Objective

The purpose of this nonrandomized retrospective study was to report our new procedures using polyethylene glycolic acid (PGA) felt with fibrin sealant to prevent severe pancreatic fistula in patients undergoing pancreatic surgery.

Methods

From 2000 to 2008, 54 and 63 patients underwent pancreaticoduodenectomy (PD) and distal pancreatectomy (DP), respectively. Of those patients, we applied PGA felt with fibrin sealant to 18 PD patients and 26 DP patients. In PD patients, the PGA felt was wrapped around the pancreatic suture site, while in DP patients, the PGA felt was wrapped around the predictive division site. The pancreaticojejunostomy site in PD patients and the cut stump in DP patients were coated with fibrin sealant. We compared the occurrence rates for severe postoperative pancreatic fistula (POPF) that occurred after PD or DP both with and without our new procedures.

Results

Before introduction of our procedures, severe POPF developed in 14 of 36 PD patients (39%) and 10 of 37 DP patients (27%). In contrast, after introduction of our procedures, the incidence of POPF was only one in both of 18 PD (6%; P?=?0.016) and 26 DP (4%; P?=?0.017) patients.

Conclusion

In summary, our procedure using PGA felt with fibrin sealant may reduce the risk of severe POPF.  相似文献   
78.

Background

This retrospective study evaluated the surgical learning curve and outcomes of thoracolaparoscopic esophagectomy.

Patients and Methods

The study group comprised a series of 92 patients with preoperatively diagnosed resectable thoracic esophageal cancer. Additionally, the surgical outcomes in 79 esophageal cancer patients receiving open esophagectomies were compared. All patients underwent thoracolaparoscopic esophagectomy in the lateral decubitus position. The short- and long-term outcomes were evaluated, and the surgical learning curve was assessed.

Results

The total operation time was 477.8?±?102.2 min, the thoracoscopic time was 157.9?±?61.3 min, the total blood loss was 554.4?±?280.5 ml, and the number of retrieved lymph nodes was 34.3?±?14.3. Postoperative morbidity was observed in 23 patients. After the surgeon??s first 40 cases, the surgical technique and short-term outcomes were stable. The 5-year disease-specific survival was 66.6% and the 5-year overall survival was 64.6% in patients receiving R0 thoracolaparoscopic esophagectomy. Comparison of 5-year disease-specific survival rate according to tumor?Cnode?Cmetastasis stage between patients receiving R0 thoracolaparoscopic esophagectomy and conventional open esophagectomy showed that there were no significant differences in survival in any stage between the two groups. Loco-regional recurrence was observed in 6 patients, distant recurrence in seven, and combined recurrence in nine after R0 thoracolaparoscopic esophagectomy. There was no significant difference in the pattern of recurrence between the two groups.

Conclusions

Thoracolaparoscopic esophagectomy for esophageal cancer was technically feasible and oncologically satisfactory, according to the surgical learning curve.  相似文献   
79.
Catamenial pneumothorax is a subclass of secondary spontaneous pneumothorax occurring in women in their third or fourth decade of life. We describe a classic and typical case of this disease. Although it is believed to be rare historically, the recent study showed the much higher prevalence. It is essential to consider this disease in recurrent spontaneous pneumothorax of a middle-aged woman.  相似文献   
80.
BACKGROUND: Pulmonary metastasectomy has become the standard therapy for various metastatic malignancies to the lungs; however, few data have been available about lung metastasectomy for hepatocellular carcinoma. To confirm the role for resection of pulmonary metastases for such tumors, we reviewed our institutional experience. METHODS: Between 1993 and 2005, 12 patients with pulmonary metastases from hepatocellular carcinomas underwent complete pulmonary resection. All patients had undergone curative resection of their primary hepatocellular carcinomas and also had obtained or had obtainable locoregional control of their primaries. Various perioperative variables were investigated retrospectively to analyze the possible prognostic factors for overall survival and pulmonary metastases-free survival after pulmonary metastasectomy. RESULTS: Nine patients were male and three were female (median age, 53 (range, 43-80) years). Overall survival rate after metastasectomy was 80.8%, 57.7%, and 28.9% at 1, 2, and 5 years, respectively. Pulmonary metastases-free survival rate was 64.2%, 32.1%, and 21.4% at 1, 2, and 5 years, respectively. Five patients presented recurrences in the remaining liver before pulmonary metastases, but hepatic recurrences at this interval did not affect an overall survival after pulmonary metastasectomies. Two patients had undergone living-related liver transplantation. The maximum tumor size of the pulmonary metastasis < 3 cm was the only favorable prognostic factor for overall survival (P = 0.0006), whereas there was no significant prognostic factor for pulmonary metastases-free survival. CONCLUSIONS: Pulmonary metastasectomy for hepatocellular carcinoma in selected patients was well justified when the maximum tumor size was <3 cm.  相似文献   
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