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71.
72.
The auditory brainstem response (ABR) and the eighth nerve compound action potential (CAP) were measured using click stimuli to investigate the agerelated alteration in the auditory function in 66 guinea pigs consisting of four age groups. With advancing age, a gradual elevation of the thresholds in both the ABR and CAP was clearly seen, together with the prolonged latencies for waves I, II, III, and IV to clicks at 95 dBpeSPL in the ABR. There were some individual differences in either threshold elevation or latency prolongation of both the ABR and CAP in aged guinea pigs. These findings suggest that the effect of individual differences on degenerative aging processes of the auditory system should be considered in selected aged animals, although a significant elevation of the neural auditory threshold is clearly found with advancing age as a whole.  相似文献   
73.
A 60-year-old woman with superficial spreading melanoma in situ, measuring 2.5 mm in diameter, was examined. She had noticed a very small pigmented lesion 1.2 mm in diameter on her left lower leg in April of 1989. By April of 1990, it had grown to 2.5 mm in diameter. Its edge was irregular, and its color was variegated black to brown. Skin surface markings had disappeared in the center portion. Histopathologically, the lesion was asymmetrical. Atypical large cells nested in the lower epidermis and were scattered singly in the mid and upper epidermis, as seen in Paget's disease. At the periphery of the lesion, single large tumor cells were scattered in the mid epidermis. The tumor cells reacted to monoclonal anti-melanoma antibody HMB-45.  相似文献   
74.
Active specific immunotherapy using the immune reaction of a low-dose irradiated tumor tissue was studied on the transplanted MM46 tumor of female C3H/He mice after radiotherapy. MM46 tumor cells were inoculated into the right hind paws of mice. On the 5th day, irradiation with the dose of 3000 rad was performed. On the 11 th day, tumor cells and mononuclear cells, which were separated from the low-dose irradiated tumor tissue (2000 rad on the fifth day), were injected into the left hind paws of the tumor-bearing mice. Effectiveness of this active specific immunotherapy against tumor was evaluated by the regression of tumor and survival rate of mice. Tumor was markedly regressed and survival rate was significantly increased by the active specific immunotherapy.  相似文献   
75.
PURPOSE: A single-arm phase II multicenter trial of the combination of cyclophosphamide (C), epirubicin (E), and 5-fluorouracil (F) followed by docetaxel as neoadjuvant chemotherapy is being conducted by the Japan Breast Cancer Research Group. This report describes an interim analysis of the clinical response and safety of 79 patients who finished preoperative chemotherapy and surgery. PATIENTS AND METHODS: Patients with operable breast cancer received C at 500 mg/m2, E at 100 mg/m2, and F at 500 mg/m2 every 21 days for 4 cycles followed by docetaxel at 75 mg/m2 every 21 days for 4 cycles. RESULTS: Of the 79 patients evaluable for analysis the median age was 46 years (28-59), and 61 patients (77.2%) had T2 tumors. A total of 312 of 316 (98.7%) cycles of CEF and 296 of 312 (94.9%) cycles of docetaxel were administered. Average total cumulative dose was 92% and 95% for CEF and docetaxel, respectively. The rate and grade of edema, neuropathy, arthralgia and myalgia were higher with docetaxel than with CEF. The overall clinical response rate was 70.9%. Breast conserving surgery was performed in 31 of 42 patients (73.8%) with a base-line tumor size of more than 3 cm. CONCLUSIONS: Interim data suggest that CEF followed by docetaxel is an active and tolerable neoadjuvant chemotherapy regimen. A final analysis is planned for 2005.  相似文献   
76.
The fate of stem cells, such as neural stem cells and hematopoietic stem cells, depends on strictly regulated signaling events including activation of nuclear receptors, resulting in subsequent gene induction. Recently, we demonstrated that PPARgamma, a ligand-activated nuclear receptor, plays an important role in regulating the proliferation and differentiation of murine neural stem cell (NSC). NSC prepared from heterozygous PPARgamma-deficient mouse exhibited a slower growth rate compared with that of wild-type mouse, which was also demonstrated in PPARgamma-knockdown NSC that was generated by the lentiviral-vector-mediated RNA interference approach. These studies have important implications for understanding central nervous system functions and developing a therapy for neurodegenerative disorders. In this review, recent findings on stem cell biology, especially focusing on nuclear receptors in NSCs, including our current study, will be discussed.  相似文献   
77.
We describe a 16-year-old girl with malignant fibrous histiocytoma (MFH) of the heart complicated by factor XI deficiency. The preoperative diagnosis was left atrial myxoma. We decided to perform the operation owing to a normal bleeding time. Operative findings suggested a malignant tumor. The patient was a Jehovah's Witness, and extensive excision was not performed because blood transfusion was not allowed. We resected as much of the tumor and left atrial appendage as possible. The pathologic diagnosis was MFH. Excessive bleeding was not observed during the operation. Bleeding time helps to determine whether a surgical procedure is indicated in patients with factor XI deficiency.  相似文献   
78.
A 58-year-old man presented with an extremely rare case of "pure type" spinal tanycytic ependymoma associated with hematomyelia manifesting as sensory disturbance of the bilateral hands and weakness of the right arm. Magnetic resonance imaging demonstrated a tumor in the spinal cord from C-2 to C-4 levels. The soft gelatinous tumor was subtotally resected and the adjacent chronic liquid hematoma was aspirated. The immunohistochemical and ultrastructural findings indicated a diagnosis of tanycytic ependymoma.  相似文献   
79.
Measurements of changes in finger skin blood flow with laser Doppler perfusion imaging (LDPI) in response to cold provocation test (10 degrees C, 10 min) were performed in 12 men suffering from vibration induced white finger (VWF) and 13 exposed controls. The mean perfusion values in both groups reduced markedly as a result of immersion of the hand in cold water. In the controls, however, the mean value increased gradually until the end of the cold provocation, while that in the VWF subjects remained at the lowest level. After removal of the hand from the cold water, the skin blood perfusion in the controls recovered rapidly and nearly reached the baseline value. In the VWF subjects, it had a slight increase immediately following the cold immersion but no tendency to rise as the time span increased. Analysis of covariance controlling for possible confounders revealed that the VWF subjects had significantly lower perfusion values compared to the controls in the last several minutes of the cold provocation and the following recovery. These findings suggest that the LDPI technique enables visualizing and quantifying the peripheral vascular effects of cold water immersion on the finger skin blood perfusion and thus has the potential of providing more detailed and a&curate information that may help detect the peripheral circulatory impairment in the fingers of vibration-exposed workers.  相似文献   
80.
Purpose We evaluated the relationship between liver histology and postoperative improvement of liver function after surgery for Budd-Chiari syndrome (BCS).Methods Over a period of 23 years, we operated on 46 patients with BCS by reconstructing the occluded inferior vena cava (IVC) and reopening as many occluded hepatic veins as possible. We divided the patients into a liver cirrhosis group (group I, n = 30) and a hepatic fibrosis or liver congestion group (group II, n = 16), and compared the ages, duration of illness, preoperative liver function, changes in liver function, and changes in esophageal varices (EV).Results There were no hospital deaths. In group I the patients were older, and the duration of illness was longer. The group I patients also had a lower thrombotest percentage and a higher serum ammonia. The indocyanine green clearance (ICG) test showed more remarkable improvement in liver function in group II. The rate of disappearance of EV was also higher in group II.Conclusion Surgery during the early stage of BCS is important in improving postoperative liver function.  相似文献   
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