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Cardiac sympathetic neuronal function is closely coupled with beta-adrenoceptors and adrenergic signaling. However, the recovery process of sympathetic neuronal function and beta-adrenoceptors after reperfusion following transient ischemia is not fully understood. Accordingly, this study was performed to investigate serial changes in sympathetic neuronal function and beta-adrenoceptors after transient myocardial ischemia. METHODS: The left coronary artery of male Wister rats was ligated for 15 min followed by reperfusion. A dual-tracer method of (131)I-metaiodobenzylguanidine ((131)I-MIBG) and (125)I-iodocyanopindolol ((125)I-ICYP) was used to assess cardiac sympathetic neuronal function and beta-adrenoceptor density on days 1, 3, 7, 14, and 28 after reperfusion. Myocardial norepinephrine (NE) content in ischemic regions (IR) and in remote regions (RR) and hemodynamic indices were determined. Using a membrane preparation of the rat heart after reperfusion, the maximum specific binding (B(max)) of beta-adrenoceptors was compared with (125)I-ICYP accumulation. RESULTS: The maximum value of the rate of change in left ventricular (LV) pressure (dP/dt(max)) tended to decrease on day 1 after reperfusion but recovered thereafter. Myocardial NE content was significantly reduced in IR compared with RR on day 1 (272 +/- 49 vs. 487 +/- 93 ng/g, P < 0.01), and the decrease became more severe on day 14 (36 +/- 19 vs. 489 +/- 132 ng/g, P < 0.01) and day 28 (37 +/- 14 vs. 455 +/- 216 ng/g, P < 0.01). Decrease in the IR-to-RR uptake ratio of (131)I-MIBG was modest on day 1 (0.64 +/- 0.12) and became more severe on days 7 and 14 (0.38 +/- 0.12 and 0.35 +/- 0.13, respectively). This reduction was partially restored on day 28 (0.50 +/- 0.18). In contrast, the IR-to-RR uptake ratio of (125)I-ICYP was severely decreased until day 3 (0.60 +/- 0.13 on day 1 and 0.54 +/- 0.19 on day 3) and recovered thereafter. On day 3, B(max) was significantly lower in IR than in RR (83 +/- 17 vs. 100 +/- 12 fmol/mg, P < 0.05), but the dissociation constant did not differ between the 2 regions. CONCLUSION: The recovery course of cardiac (131)I-MIBG uptake after reperfusion following transient ischemia is quite different from that of (125)I-ICYP. Simultaneous scintigraphic portrayal of beta-adrenoceptors together with (131)I-MIBG would provide useful information regarding adrenergic system signaling in patients with coronary artery disease.  相似文献   
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We followed up the patients with fulminant hepatic failure who admitted in our hospital and investigated clinical problems raised in the patients who underwent living-related liver transplantation (LRLT). Among 15 patients with fulminant hepatic failure 6 were managed without LRLT and 3 patients survived, and the survival rate was 50%. Other 9 patients received LRLT, and 2 of these 9 died with their complications after the transplantation. Thus the survival rate by LRLT in fulminant hepatic failure was 77.8%. Brain CT scan examination showed severe brain edema in a patient and the edema did not improve after LRLT. Another patient suffered from development of fungal infection in her lungs after LRLT. We suspected the presence of subclinical infection in the preoperation period. The recovery from brain edema and the existence of subclinical infection are mostly difficult to evaluate but are very important for obtaining a good output. These results suggest that LRLT is a promising procedure for treatment of fulminant hepatic failure but a close cooperation between physicians of internal medicine and transplantation surgery from preoperative management until postoperative period is necessary.  相似文献   
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In order to evaluate the load on the low back of teachers in nursery schools, basic activity, working posture, child-lifting, and desk-lifting were analyzed for eight nursery teachers using video recording. The trunk inclination angle (TIA) was also measured continuously during full workshifts for 20 nursery teachers using an inclination monitor. The nursery teachers in the 0–1 (year) age class more often adopted low working postures, sitting on the floor and kneeling, while teachers in the 4–5 age class more frequently adopted high working postures, standing and sitting on a chair. The mean of TIA among all subjects was 20°. The time spent at a TIA of more than 20° represented 43% of the workshift. The mean and time distribution of TIA did not differ between the age classes. The frequency of trunk-lifting from severe bending forward (TIA > 45°) was 86 times/hour on average. The frequency of trunk-lifting was highest in the 0–1 age class. The number of times of child-lifting was 46 in the 0–1 age class, while it was 1 in the 4–5 age class.  相似文献   
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This study was undertaken to evaluate the use of Indium-111-labeled leukocyte (111In-WBC) imaging compared with Technetium-99m pertechnetate (99mTcO4-) imaging in 19 patients with rheumatoid arthritis (RA) and 8 with osteoarthritis. Knee and wrist joints were evaluated for both radionuclides. The results indicated a good correlation of the clinical assessment of pain and swelling with joint uptake ratio (JUR) between 111In-WBC and 99mTcO4- in RA and osteoarthritis patients. We observed a discrepancy in both imagings in "burned out" cases. It was concluded that a JUR of 111In-WBC could distinguish active RA from inactive RA or osteoarthritis at a value of 1.15 and that the use of 111In-WBC was a more reliable procedure than 99mTcO4-.  相似文献   
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Fractionated stereotactic radiotherapy of small intracranial malignancies   总被引:4,自引:0,他引:4  
Purpose: To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) in patients with small intracranial malignancies.

Methods and Materials: From July 1991 to March 1997, 80 patients with a total of 121 brain or skull-base tumors were treated with FSRT alone, and were followed for periods ranging from 3 to 62 months (median 9.8). The majority of patients received 42 Gy in 7 fractions over 2.3 weeks, but in July 1993, protocols using smaller fraction doses were introduced for patients whose radiation-field diameters were larger than 3 cm or whose tumors were close to critical normal tissues.

Results: For 64 patients with metastatic brain tumors the overall median survival was 8.3 months and 1-year actuarial survival rate was 33%. Significant prognostic factors were: the presence of extracranial tumors, pre-treatment performance status, and the lung as a primary site. Patients without extracranial tumors prior to FSRT had a median survival of 21.2 months. For seven patients with high-grade glioma, 1-year actuarial local control rate was 75%, with a median survival of 10.3 months. For patients with skull-base tumors the local control was achieved in 6 of 6 patients (100%), with a median survival of 30.7 months. No one suffered from acute complications, but three patients, two of whom had undergone FSRT as the third course of radiotherapy, developed late radiation injuries.

Conclusion: Overall high local control and low morbidity rates suggest that FSRT is an effective and safe modality, even for those with a history of prior irradiation. However, patients with risk factors should be treated with smaller fraction doses.  相似文献   

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