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51.
The sympathetic nervous system is believed to play a major role in regulating cardiovascular function during exercise. However, only a few direct measurements of sympathetic nervous activity during whole body dynamic exercise have been attempted. In the present study, we have established a method to allow routine measurement of renal sympathetic nerve activity (RSNA) and cardiovascular function during treadmill exercise in rats. We trained Wistar rats to run on the treadmill for a week before the surgery. At least 2 days before the experiment, electrodes for recording RSNA, electrocardiogram and electromyogram, and catheters for the measurements of systemic arterial and central venous pressures were implanted under aseptic conditions. Satisfactory signal to noise ratios were obtained in 80 %, 60 % and 40 % of the group at 1-3 days, 4-7 days and 8-10 days after the surgery, respectively. RSNA was successfully recorded without contamination by external noise during treadmill exercise. Treadmill exercise resulted in an abrupt increase in RSNA, by 82 % at 0.5 min, and then reached a stable level of ~40 % during the period of 5-30 min after the onset of treadmill exercise. This experimental model allows us to study the neural mechanisms involved in the regulation of cardiovascular function during dynamic exercise in rats.  相似文献   
52.
Two flat adenomas and a flat mucosal carcinoma of the colon were reported in patients with synchronous and metachronous colonic carcinomas. These lesions were almost flat and were not detected by preoperative endoscopic examinations. Colonoscopists should be aware of the presence of flat adenomas, which can be easily missed, and recognize them as lesions that play an important role in the "adenoma-carcinoma sequence."  相似文献   
53.
We present five cases of adenomatous hyperplasia (AH) containing minute hepatocellular carcinoma (HCC) in cirrhotic liver. All the patients were Japanese, four males and one female, ranging in age from 60 to 80 years. Two of the specimens were obtained at surgery and the others at autopsy. The AH specimens ranged from 2.0 to 3.0 cm in diameter, and the maximum diameter of HCC foci in the AH was 2.0 cm. Histologically, apart from the HCC foci, the AH specimens showed intrinsic atypia, suggesting preneoplastic change. These features included an increase of both cellularity and the nucleo-cytoplasmic ratio, distortion of cord structure and pseudoacinar formation. All of the AH specimens contained typical portal triads. Details of diagnostic imaging were also obtained in four cases. The findings of the present study support the possibility that AH with intrinsic atypia is a preneoplastic lesion of HCC. The sequence of "adenomatous hyperplasia with intrinsic atypia-HCC foci" would thus represent part of the early phase of hepatocarcinogenesis in humans.  相似文献   
54.
S Ohno  D Korenaga  H Kuwano  M Mori  K Sugimachi 《Cancer》1989,63(10):1951-1955
The relationship between DNA ploidy and effects of preoperative hyperthermo-chemo-radiotherapy were investigated in 118 patients who underwent esophageal resection and reconstruction for carcinoma of the esophagus, including 56 treated with hyperthermo-chemo-radiotherapy (HCR therapy) and 62 treated with chemo-radiotherapy (CR therapy). DNA ploidy patterns were grouped into low and high ploidies, according to the degree of dispersion and the peak value on the DNA histogram. In the low ploidy group, there were no significant differences in the prognosis and histologic effects between the HCR and CR therapies. In the high ploidy group, however, the difference in survival curves was statistically significant, the 3-year survival rates of patients given HCR therapy and CR therapy being 26.7% and 10.7%, respectively (P less than 0.05). The HCR therapy increased the rate of "markedly effective" in the resected tissue compared with findings in cases of CR therapy. These findings show the positive effects of the HCR therapy for carcinoma of the esophagus, especially for patients with an aneuploid profile and a poor prognosis.  相似文献   
55.
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 1971–1975 to 62.3%during 1981–1985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 1971–1975and 69.7% during 1981–1985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 37–40 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe.  相似文献   
56.
Two Puralpha-binding proteins (PurBPs) were found in nuclear extract from mouse brain during P4-P10 by the overlay assay. At P14, they were decreased significantly in nuclear extract and increased in the S3 fraction, indicating their dynamic translocation during development. Western blot analysis also demonstrated concomitant translocation of Puralpha with the PurBPs during P7-P14, when neuronal circuit proceeds. Immunocytochemical study with cultured hippocampal neurons from rat E18 confirmed that nuclear Puralpha was translocated to cytoplasm after plating for 7-14 days. These results suggest that spatiotemporal translocation of Puralpha with the PurBPs from nuclei to cytoplasm has a crucial role in neuronal development.  相似文献   
57.
By Western blot analysis, the expression level of aquaporin (AQP) 5 in the submandibular gland (SMG) was found to be different among individual rats of the Sprague-Dawley (SD) strain. Such differences were observed for AQP5 but not for AQP1 and consequently the SD strain was divided into two groups, one expressing a high level of AQP5 and the other a low one. The difference in average intensity of expression between the two groups was more than twofold. Immunohistochemical analysis of the SMG demonstrated that the AQP5 protein was localized in the basal and apical/lateral plasma membrane of acinar cells in rats expressing the high level of AQP5. In the rat expressing the low level, however, this channel protein was localized strongly in the apical/lateral plasma membrane, but only very weakly in the basal membrane of the acinar cells. Such a diverse localization of AQP5 was confirmed by Western blotting as well. Breeding between brother and sister was repeated for two times within high expressers and low expressers to obtain the third generation progenies (F2); the AQP5 level of the SMG in the third generation (F2 rats) from high expressers was significantly higher than the F2 from low expressers. Our present study suggests the existence of genetic variation in the expression of a water channel protein, AQP5, in rats.  相似文献   
58.
A case of giant cell carcinom of the pancreas is reported herein. The patient is a 67-year-old Japanese woman complaining of ascites, general fatigue, loss of weight, abdominal distention, nausea, and vomiting. Cytological diagnosis of ascites revealed adenocarcinoma. At autopsy, a whitish tumor measuring around 5 cm in diameter was found at the head of the pancreas. Metastasis was seen only in the liver. Histological examination displayed bizarre multinucleated giant cells occasionally phagocytosing the tumor cells and neutrophils.  相似文献   
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