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51.
(1) Functional commencements of the neuronal elements in the cerebellar cortex of young rats were studied electrophysiologically by means of laminar field potential analyses in the cortex on stimulation of the cerebellar surface (Loc) and the white matter (WM). (2) The antidromic action potential of Purkinje cells on the WM stimulation was observed at one day after birth. The climbing fiber excitation of Purkinje cells on the stimulation was noted at 3 days after birth. (3) The mossy fiber-granule cell synapses were found to function at 10 days after birth and the Golgi cell inhibition of granule cells could be proved at the same time. The excitatory action of parallel fibers and the inhibitory action of basket-stellate cells on Purkinje cells appeared simultaneously at about 12 days after birth. The transverse distribution across the cerebellar folium of the basket-stellate cell inhibitory action on Purkinje cells was found to be narrow up to 60 days after birth. (4) These results concerning the dates of commencement of excitatory and inhibitory synaptic actions in the cerebellar cortex were compared with those of synaptogenesis studied morphologically, and some implications of the dates in the functional development of the cerebellar cortex were discussed. 相似文献
52.
Restenosis after percutaneous transluminal coronary angioplasty: pathologic observations in 20 patients 总被引:14,自引:0,他引:14
M Nobuyoshi T Kimura H Ohishi H Horiuchi H Nosaka N Hamasaki H Yokoi K Kim 《Journal of the American College of Cardiology》1991,17(2):433-439
Histopathologic examination was performed in 20 patients undergoing antemortem coronary angioplasty. Thirty-four lesions were dilated and the interval between coronary angioplasty and death ranged from several hours to 4 years. Intimal proliferation of smooth muscle cells, as a major cause of restenosis, was observed in 83% to 100% of 28 lesions examined 11 days to 2 years after coronary angioplasty. In 20 lesions examined within 6 months, proliferating smooth muscle cells were predominantly of the synthetic type and there was abundant extracellular matrix substance chiefly composed of proteoglycans. In eight lesions examined between 6 months and 2 years, contractile type smooth muscle cells were dominant and extracellular matrix was composed chiefly of collagen. In three lesions examined after 2 years, evidence of antemortem coronary angioplasty was hardly identifiable and these lesions were almost indistinguishable from conventional atherosclerotic plaque. These temporal changes in histologic pattern provide a pathologic background for clinical reports that restenosis is predominantly found within 6 months after coronary angioplasty. Morphometric analysis revealed that the extent of intimal proliferation was significantly greater in lesions with evidence of medial or adventitial tears than in lesions with no or only intimal tears. 相似文献
53.
A bout of eccentric exercise confers protection against subsequent bouts of the same exercise. This study investigated whether the protective effect would be produced similarly between old and young adults. Eight old men (70.5 ± 4.1 years) and ten young men (20.4 ± 2.0 years) performed two bouts of eccentric exercise of the elbow flexors (six sets of five eccentric actions) separated by 4 weeks. Changes in maximal isometric strength, range of motion (ROM), upper arm circumference (CIR), plasma creatine kinase (CK) activity, myoglobin (Mb) concentration, and muscle soreness (SOR) before, immediately after, and 1, 24, 48, 72 and 96 h following exercise were compared between bouts, and between groups by a two-way repeated measures ANOVA. Changes in the measures following the first bout were significantly (P < 0.05) smaller for the old than the young group. The young group showed significantly (P < 0.05) smaller changes in all measures following the second bout than the first bout; however, the old group had the protective effect only for ROM, Mb, and SOR. The magnitude of the effect observed for ROM and Mb concentration in the old group was significantly (P < 0.05) smaller compared with that of the young group. These results suggest that the protective effect conferred by the first bout was less for the old than the young group. This may be due to the less muscle damage after the first bout in the old subjects, but it is also possible that the protective effect of old adults does not last as long as that of young adults. 相似文献
54.
Hideyuki Mizuno Tatsuaki Kanai Yohsuke Kusano Susumu Ko Mari Ono Akifumi Fukumura Kyoko Abe Kanae Nishizawa Munefumi Shimbo Suoh Sakata Satoshi Ishikura Hiroshi Ikeda 《Radiotherapy and oncology》2008,86(2):258-263
INTRODUCTION: The characteristics of a glass dosimeter were investigated for its potential use as a tool for postal dose audits. Reproducibility, energy dependence, field size and depth dependence were compared to those of a thermoluminescence dosimeter (TLD), which has been the major tool for postal dose audits worldwide. MATERIALS AND METHODS: A glass dosimeter, GD-302M (Asahi Techno Glass Co.) and a TLD, TLD-100 chip (Harshaw Co.) were irradiated with gamma-rays from a (60)Co unit and X-rays from a medical linear accelerator (4, 6, 10 and 20 MV). RESULTS: The dosimetric characteristics of the glass dosimeter were almost equivalent to those of the TLD, in terms of utility for dosimetry under the reference condition, which is a 10 x 10 cm(2) field and 10 cm depth. Because of its reduced fading, compared to the TLD, and easy quality control with the ID number, the glass dosimeter proved to be a suitable tool for postal dose audits. Then, we conducted postal dose surveys of over 100 facilities and got good agreement, with a standard deviation of about 1.3%. CONCLUSIONS: Based on this study, postal dose audits throughout Japan will be carried out using a glass dosimeter. 相似文献
55.
A patient who received antithymocyte globulin therapy for aplastic anemia due to D-penicillamine therapy is described. Bone marrow recovery and peripheral blood recovery were complete 1 month and 3 months, respectively, after treatment, and blood transfusion or other therapies were not necessary in a follow-up period of more than 2 years. Use of antithymocyte globulin may be the optimal treatment of D-penicillamine-induced aplastic anemia. 相似文献
56.
Asano K Ohkuma H Kudo K Takemura A Suzuki S Kubo O 《No shinkei geka. Neurological surgery》2002,30(6):631-637
We report successful operations for a meningeal hemangiopericytoma using sufficient amounts of Preoperative Autologous Transfusion (PAT) and Hemodilutional Autologous Transfusion (HAT). A 23-year-old woman with amenorrhea and bilateral visual field disturbance was found to have a huge intracranial tumor. MRI showed a well-enhanced cystic mass in the left middle fossa, suprasellar, intrasellar, sphenoidal sinus, and cavernous sinus. Preoperatively, the tumor was thought to be a cystic pituitary tumor or meningioma. Surgical removal was planned in three steps. The first operation was carried out via the transsphenoidal approach. Total blood loss was 1348 ml and 2 MAP infusion were required to control bleeding. Histopathological diagnosis was hemangiopericytoma. After preparation of PAT 400 ml and HAT 800 ml, we carried out the second partial removal operation mainly via the interhemispheric approach. Total blood loss was 1829 ml and required autologous transfusion only. After preparation of PAT 1200 ml and HAT 400 ml, the last total removal operation was carried out mainly via the pterional and subtemporal approach. Total blood loss was 1813 ml and required autologous transfusion only. We needed 2 MAP infusion in the first operation, but were able to perform total removal successfully without homologous blood transfusion because a sufficient amount of PAT and HAT had been prepared preoperatively. Hemangiopericytoma required postoperative radiation therapy to avoid local recurrence. After successful removal of the tumor surgically, postoperative radiation therapy was able to be carried out efficiently. 相似文献
57.
58.
PURPOSE: This study investigated changes in indirect markers of muscle damage after endurance exercise of the elbow flexors and compared the changes with those after maximal eccentric actions (Max-ECC) of the elbow flexors. METHODS: Eighteen male students rhythmically lifted (1 s) and lowered (1 s) a light dumbbell (1.1-1.8 kg: 9% of MIF) in 60-180 degrees of elbow joint angle for 2 h (2-h Ex). Maximal isometric force (MIF), relaxed (RANG) and flexed elbow joint angles (FANG), upper-arm circumference (CIR), muscle soreness (SOR), B-mode ultrasound (US), and plasma creatine kinase (CK) activity were assessed before and immediately after, and up to 96 h after exercise. RESULTS: All measures were altered significantly (P < 0.05) after 2-h Ex in a similar time course to Max-ECC; however, changes in RANG, FANG, CIR, US, and CK (peak: 356 +/- 121 IU.L-1) were significantly (P < 0.05) smaller compared with those after Max-ECC. SOR developed immediately after 2-h Ex and peaked 24-48 h after exercise. MIF dropped to 44.1% of the preexercise level, which was significantly (P < 0.05) lower than that after Max-ECC (58.1%), immediately postexercise. MIF recovered to 79.8% at 24 h, and 97.8% at 96 h postexercise, which was a significantly (P < 0.05) faster recovery compared with that of Max-ECC (73.1% at 96 h). CONCLUSION: These results showed low-intensity continuous muscle contractions (3600 times) resulted in muscle damage; however, the magnitude of the muscle damage was less severe, and the recovery was faster compared with 12 maximal eccentric muscle actions. 相似文献
59.
A 57-year-old woman complained of lumbago of 1 year’s duration. Radiographs showed a compression fracture of the third lumbar
vertebra. CT and MR images revealed an enhancing mass confined to the vertebral body suggestive of a malignant process. A
blood-pool scintigram with 99mTc-human serum albumin combined with DTPA (HSA-D) revealed marked accumulation. This strongly suggested a hemangioma, which
was confirmed by biopsy.
Received: 26 October 2000 Revision requested: 21 November 2000 Revision received: 23 December 2000 Accepted: 28 December 相似文献
60.
Increasing methylation of the CDKN2A gene is associated with the progression of adult T-cell leukemia 总被引:12,自引:0,他引:12
In this study, we examined the methylation status of the CDKN2A gene in patients with different forms of adult T-cell leukemia (ATL) using Southern blot analysis, methylation-specific PCR (MSPCR), and nucleotide sequencing. We found that the CDKN2A gene was more frequently methylated in fresh tumor cells isolated from patients with acute ATL (47%) or lymphoma-type ATL (73%) than in those with less malignant chronic (17%) and smoldering (17%) ATL. In addition, deletions of the CDKN2A gene were found in 24% of acute ATL patients; thus, abnormalities of the CDKN2A gene totaled 71% in acute ATL patients. In contrast, no CDKN2A gene methylation was found in asymptomatic carriers or uninfected individuals. Methylation of the p15 gene was not found in any samples from 36 ATL patients. Direct sequencing of the CDKN2A gene after sodium bisulfite treatment of genomic DNA revealed that the methylation of CpG sites had occurred in 24 of 32 ATL cases (75%) including chronic and smoldering ATL, even when MSPCR and the Southern blot had failed to detect CDKN2A gene methylation. Among fresh ATL samples with methylation, methylation was detected in the promoter region and exon in 17 of 24 cases, and methylation in the exon without promoter region was detected in 7 of 24 cases. In one case, the pattern of methylation proved to be different between peripheral blood cells and lymph node cells, suggesting the presence of multiple subclones with regard to methylation patterns, despite the same HTLV-I integration site. Quantitative PCR showed a marked decrease in CDKN2A mRNA expression in the cells with a methylated CDKN2A gene, especially if the promoter region was methylated. These findings suggest that CpG methylation decreases CDKN2A expression and represents a critical factor in the disease progression of ATL. 相似文献