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991.
Selective neuronal survival and upregulation of PCNA in the rat inner retina following transient ischemia 总被引:1,自引:0,他引:1
Ju WK Kim KY Hofmann HD Kim IB Lee MY Oh SJ Chun MH 《Journal of neuropathology and experimental neurology》2000,59(3):241-250
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells. 相似文献
992.
Effect of melatonin on the regulation of proenkephalin and prodynorphin mRNA levels induced by kainic acid in the rat hippocampus 总被引:1,自引:0,他引:1
The in vivo short-term effect of melatonin on kainic acid (KA)-induced proenkephalin (proENK) or prodynorphin (proDYN) mRNA, and on AP-1 protein levels in the rat hippocampus, were studied. Melatonin (5 mg/kg) or saline was administered intraperitoneally (i.p.) to rats 30 min prior to and immediately after i.p. injection of KA (10 mg/kg). Rats were sacrificed 1 and 3 h after KA injection. The proENK and proDYN mRNA levels were significantly increased 3 h after KA administration. The elevations of both proENK and proDYN mRNA levels induced by KA were significantly inhibited by the preadministration with melatonin. The increases of proENK and proDYN mRNA levels induced by KA were well-correlated with the increases of c-Fos, Fra-2, FosB, c-Jun, and JunB protein levels, which were significantly increased 3 h after KA administration and effectively inhibited by administration with melatonin. In an electrophoretic mobility shift assay, both AP-1 and ENKCRE-2 DNA binding activities were increased by KA, which were also attenuated by the administration of melatonin. In addition, cross-competition studies revealed that AP-1 or ENKCRE-2 DNA binding activity was effectively reduced by the 50x unlabeled cross-competitor. Therefore, these data suggest that melatonin has an inhibitory role in KA-induced gene expression, such as proENK and proDYN mRNA expression, and this may be due to a reduction of KA-induced AP-1 or ENKCRE-2 DNA binding activity. 相似文献
993.
Effects of small dose of brotizolam on P300 总被引:1,自引:0,他引:1
Hayakawa T Uchiyama M Enomoto T Nakajima T Kim K Shibui K Kudo Y Ozaki S Nakajima T Suzuki H Urata J Okawa M 《Psychiatry and clinical neurosciences》2000,54(3):319-320
Nine healthy men (mean age, 22.2 years) participated in two experimental sessions cross-overed randomly in a double blind manner; one with a placebo and the other with 0.125 mg of brotizolam (BTZ) administered in the morning. Resting electroencephalogram and event-related potential under oddball paradigm was recorded before and 1, 2, 4, 6 and 8 h after the administration. Mean 30-msec bin amplitude from 240 msec to 450 msec after the stimulus was compared between placebo and drug sessions in order to observe P300. Brotizolam reduced the amplitude of P300 at 6 h after administration. It was noted that the effects of BTZ were most marked at Fz. 相似文献
994.
Histoclinical Analysis of Early Colorectal Cancer 总被引:5,自引:0,他引:5
To evaluate the clinicopathologic characteristics of early colorectal cancer (ECC), histopathologic and clinical features
of 90 ECC patients who underwent surgical resection (not including the endoscopic polypectomized cases) and 1704 patients
with advanced colorectal cancer were analyzed. Smaller size, better histologic differentiation, less lymph node (LN) metastasis,
and better clinical outcome were observed in those with ECC than in patients with more advanced lesions. LN metastasis was
found in 5 patients with ECC among the 56 patients who underwent bowel resection (8.9%). Tumors with LN metastasis were more
frequently associated with deep submucosal invasion, absence of an adenomatous component within the tumor, sessile configuration,
and lymphovascular invasion. Tumors showing deep submucosal layer invasion were associated with a more unfavorable histologic
grade, lymphovascular invasion, LN metastasis, sessile morphology, and absence of an adenomatous component within the tumor.
Recurrence was observed in two patients who underwent local excision for their submucosal cancer. One of the patients was
salvaged after bowel resection, but one patient died of distant metastasis. From our data analysis and literature review,
extensive submucosal invasion, lymphovascular invasion, sessile configuration, and tumors with no adenomatous component should
be considered high risk factors for LN metastasis and recurrence after limited therapy. 相似文献
995.
Motoyama Y Ohnishi H Koshimae N Kanemoto Y Kim YJ Yamada T Kobitsu K 《Neurologia medico-chirurgica》2000,40(12):632-636
A 53-year-old female presented with an unruptured, large basilar trunk aneurysm manifesting only as headache with no neurological deficits, including absence of cranial nerve dysfunction. Cerebral angiography disclosed a large aneurysm with a wide neck arising from the midbasilar artery. We treated the aneurysm surgically via the posterior petrosal approach. Five angled clips were applied sequentially to the aneurysm and the basilar artery was successfully reconstructed. Electrophysiological monitoring was continued during the operation and showed no changes. Following the operation, the patient suffered from transient right abducens nerve palsy, which persisted for 3 months. Postoperative angiography showed that the aneurysm was obliterated, and the patency of the basilar artery was preserved. 相似文献
996.
Transient hyperemia immediately after rapid decompression of chronic subdural hematoma 总被引:5,自引:0,他引:5
Kim CH 《Neurosurgery》2000,47(3):791-792
997.
Blood lead concentrations and body iron status were investigated in 279 children. Blood lead concentrations showed no increase during iron depletion phase (stage I) but markedly increased from the phase of iron deficient erythropoiesis (stage II). Increased blood lead concentrations in anaemic subjects significantly decreased after iron supplementation. 相似文献
998.
Peripheral hypoechoic lesions of the prostate: evaluation with color and power Doppler ultrasound 总被引:6,自引:0,他引:6
OBJECTIVE: To assess the usefulness of color and power Doppler ultrasound in predicting the benignity and malignancy of the peripheral hypoechoic lesion of the prostate. METHODS: Thirty-nine patients who had peripheral hypoechoic lesions on transrectal ultrasound were evaluated with color and power Doppler ultrasound followed by lesion-specific transrectal ultrasound-guided biopsies. The interpretation of color and power Doppler ultrasound was not performed separately and flow signals were categorized using a combination of the two modalities. The amount of flow signals within the lesion was evaluated and categorized into three groups: increased/equal/decreased flow compared to surrounding normal tissue on ultrasound. Doppler spectra could be obtained from the lesions in 23 patients. The amount of flow signals and resistive indexes of the spectra of the lesions were compared with those of surrounding normal tissue using the Mann-Whithney U test. RESULTS: Transrectal ultrasound-guided biopsy of the hypoechoic lesions revealed prostate cancer in 20 patients and benign prostatic diseases in 19. Flow signals within the lesions were of increased/equal/decreased flow compared to surrounding normal tissue in 16/2/2 in the prostate cancer group and 3/9/7 in the benign disease group, respectively. The difference was statistically significant (p = 0.0003). Resistive indexes of the lesion were 0.58-1.0 (mean 0.75) in the prostate cancer group and 0.57-1.0 (mean 0.80) in the benign disease group, and there was no significant difference between the two groups (p = 0.82). If we consider an increased flow signal within a peripheral hypoechoic lesion as a sign of prostate cancer, color power Doppler ultrasound has a sensitivity of 80%, a specificity of 84%, and an accuracy of 82%. CONCLUSION: Evaluation of peripheral hypoechoic lesions of the prostate with color and power Doppler may enhance the diagnostic capability of transrectal ultrasound. 相似文献
999.
1000.
It has been suggested that transient osteoporosis or the bone marrow oedema syndrome (BMOS) may be the initial phase of osteonecrosis of the femoral head (ONFH) and that there may be a common pathophysiology. In this study, we have assessed the MR images of 200 consecutive patients with ONFH in respect of the BMO pattern in order to test this hypothesis. This pattern was not observed in the early stage of ONFH. The initial abnormal finding detected on the MR images was an abnormal band of intensity at the junction between the necrotic area and the normal bone. Structural damage of the head seems to result in the appearance of the BMO pattern and the development of pain in ONFH. There was no finding to support the existence of a continuum between BMOS and ONFH. 相似文献