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Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA.  相似文献   
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BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis.  相似文献   
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We have previously reported that KU-2285, a 2-nitroimidazole with a fluorinated N1-substituent (-CH2-CF2CONH(CH2)nOH, n = 2), was a promising hypoxic cell radiosensitizer. In this study the pharmacokinetics of KU-2285 and its related compounds (n = 3 and n = 4) were compared with those of etanidazole (a 2-nitroimidazole with an N1-substituent of -CH2CONH(CH2)nOH, n = 2) and its related compounds (n = 3 and n = 4) to assess the effects of incorporation of a CF2 group. The lipophilicity of the fluorinated compounds was higher than that of etanidazole, as measured by the octanol/water partition coefficient. As the number of CH2 groups increased, the lipophilicity of the compounds in both the KU-2285 and etanidazole series increased. The brain tissue levels of the fluorinated compounds were as low as those of the etanidazole derivatives, while the biological half-lives of the fluorinated compounds in peripheral nervous tissues were shorter than those of related non-fluorinated compounds.  相似文献   
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In December 2000, health insurance in Japan was instituted for the use of intravenous immunoglobulin (IVIg) therapy for the acute phase of Guillain-Barré syndrome (GBS) that required aid to walk or worse. A nation-wide questionnaire survey was made to investigate the changes in treatment. In September 2002, a letter of inquiry was sent to experienced physicians in 620 teaching hospitals associated with the Societas Neurologica Japonica and 417 associated with the Societas Paediatrica Japonica. Totally, 356 neurologists (57%) and 223 pediatricians (53%) responded. After the introduction of IVIg health insurance coverage, more than 90% thought that GBS patients should be hospitalized and given treatment. The frequency of hospitals with an intensive care unit, however, was 70%. Before IVIg therapy's inclusion in health insurance coverage, many neurologists selected plasmapheresis (88%) rather than IVIg (4%) therapy, whereas pediatricians preferred IVIg (49%) to plasmapheresis (12%). After its inclusion, 75% of neurologists selected IVIg rather than plasmapheresis (21%), whereas pediatricians selected IVIg (86%) over plasmapheresis (5%). In March 2003, new payment system based on Diagnosis Procedure Combination was introduced into 82 large hospitals, and leads to difficulties to select IVIg in the hospitals. The payment system should be revised.  相似文献   
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Objective: Reoperative coronary bypass grafting is at high risk. Particularly in redo cases where the patent graft is running near the midline of the sternum, the graft may be exposed to injury by a median sternotomy and subsequent dissection. Whereas, off-pump bypass grafting from the left axillary artery or descending thoracic artery by a left thoracotomy approach is safe for preventing graft damage.Methods: From March 1998 to February 2002, we performed off-pump coronary artery bypass grafting by a left thoracotomy approach in 9 patients. The left axillary artery was used as the inflow vessel in 4 cases, and the descending thoracic, aorta in 5.Results: The radial artery was anastomosed proximally to the axillary artery in 4 cases and the descending thoracic aorta in one case. The saphenous vein graft was anastomosed, proximally to the descending thoracic aorta in 4 cases. Transdiaphragmatic minimally invasive bypass grafting for the right coronary artery was simultaneously performed in 3 cases. Postoperative cardiac events were ventricular arrhythmia in 6 cases and supraventricular arrhythmia in 3 cases. There was no damage to the patent grafts. Postoperative coronary angiography performed, in 8 cases revealed all the grafts to be patent without stenosis. Cardiac symptoms were not found after the operation in any of the cases.Conclusions: These procedures can prevent the injury to patent grafts caused by a median sternotomy, and will be one of the useful strategies for reoperative off-pump coronary artery bypass grafting.  相似文献   
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The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction.  相似文献   
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