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31.
Hypoxia-ischemic insult in neonatal rats induced slowly progressive brain damage related to memory impairment 总被引:4,自引:0,他引:4
Mishima K Ikeda T Aoo N Takai N Takahashi S Egashira N Ikenoue T Iwasaki K Fujiwara M 《Neuroscience letters》2005,376(3):194-199
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function. 相似文献
32.
K Kunishio N Mishima T Matsuhisa K Tsuno N Matsumi T Satoh K Matsumoto T Furuta A Nishimoto T Shiraishi 《Journal of neurosurgery》1990,72(2):268-272
The proliferative capacity of brain-tumor cells was analyzed in vitro and in situ using monoclonal antibody (MAb) against deoxyribonucleic acid (DNA) polymerase alpha. For the in vitro studies, two cultured human glioma cell lines were investigated using MAb against DNA polymerase alpha, the MAb Ki-67, a serum against proliferating cell nuclear antigen (PCNA/cyclin), bromodeoxyuridine (BUdR), and an anti-BUdR MAb. During exponential growth of the cells, the percentage of polymerase alpha-positive cells (the "polymerase alpha score") ranged from 72.0% to 77.1%, the Ki-67-positive cells (the "Ki-67 score") ranged from 43.4% to 59.4%, the PCNA/cyclin-positive cells from 30.9% to 41.4%, and the BUdR labeling index from 28.6% to 39.3%. For the in situ studies, tissue from 60 human brain tumors and from two normal human brains was investigated and the polymerase alpha scores and Ki-67 scores were compared. In normal brain tissue, no immunostaining was found by either method. In brain tumors, both the polymerase alpha scores and the Ki-67 scores correlated with the histological grade of malignancy. Polymerase alpha scores were generally higher than Ki-67 scores in the same specimen, especially in malignant brain tumors. These findings suggest that immunostaining of DNA polymerase alpha is a convenient and important new method by which to estimate the cellular proliferation rate of brain tumors. Polymerase alpha scores may be closer to the growth fraction of the individual tumor than the MAb Ki-67 or other scores. 相似文献
33.
Yuta Kobayashi Alberto Ricci Isidoro Rossodivita Francesco Amenta 《Naunyn-Schmiedeberg's archives of pharmacology》1994,349(6):559-564
In the present study, the pharmacological characteristics and the anatomical localization of dopamine D2-like receptor sites in the extraparenchymal and in the intraparenchymal portion of the rabbit pulmonary artery were investigated using combined radioligand binding and light microscope autoradiography with [3H]-spiroperidol (spiperone) as a ligand. The ligand was bound to sections of the pulmonary artery in a manner consistent with the labelling of dopamine D2-like receptors with an equilibrium dissociation constant (K
d) of about 2.4±0.07 nmol/l and a maximum density of binding sites of 65±4.5 fmol/mg tissue. In contrast, binding experiments made with sections of rabbit lung did not allow the evaluation of specific binding. Light microscope autoradiography showed the development of specific silver grains within the tunica adventitia of extraparenchymal branches of rabbit pulmonary artery and of large and, to a lesser extent, of medium-sized intraparenchymal branches of the pulmonary artery. No silver grains were found within small branches of the pulmonary artery or of the pulmonary vein. Development of adventitial silver grains was inhibited by compounds active at dopamine receptors. The greater sensitivity to displacement by domperidone, haloperidol, (–)-sulpiride and bromocriptine than to displacement byN-propyl-norapomorphine, quinpirole or clozapine suggests that the [3H]-spiroperidol binding sites observed in extraparenchymal, large and medium-sized branches of the pulmonary artery belong, probably, to the dopamine D2 receptor subtype. The possible pre-junctional localization of these sites is discussed.
Correspondence to: R Amenta 相似文献
34.
SHBG titer (maximum binding capacity of sex hormone binding globulin for 17 beta-estradiol), percentage of plasma unbound estradiol, plasma unbound estradiol concentration, plasma total estradiol concentration and total testosterone concentrations were determined in ten normal premenopausal women to study the regulation mechanism of plasma unbound estradiol concentration and the physiological role of SHBG in the mechanism. The percent of unbound estradion was 1.48+/-0.37 (mean+/-standard deviation). The unbound estradiol concentration was 1.24+/-0.74 pg/ml. The total estradiol and testosterone concentrations were 84+/-50 pg/ml and 0.8+/-0.09 ng/ml. SHBG titer was 42+/-15 pmol/ml. SHBG-testosterone ratio was 51+/-11.9. There was a significantly positive correlation between total estradiol concentration and unbound estradiol concentration (r=0.95, p<0.005, y=64X+4.6). A positive correlation between unbound estradiol and bound estradiol concentration (r=0.94, p<0.005, y=0.08+0.014X) was also observed. On the other hand, there was a significant inverse relationship between unbound estradiol concentration and SHBG-testosterone ratio (r=-0.88, p<0.005, y=78-23X). These data indicate that total estradiol and testosterone and SHBG-testosterone ratio play an important role in the regulation system of unbound estradiol. 相似文献
35.
The purpose of this investigation was to analyse nurse's role in the organization of the health work at the Informatics Department of the Health Bureau of the city of Ribeir?o Preto, regarding the process of municipalization. We verified that nurses were involved in the organization of this area since its implementation. Nurses also performed organization and control activities related to the production, storage and analysis of the necessary data about the different stages of the health care, as well as training and supervising activities of the individuals who work with the information system. 相似文献
36.
Mishima K Sawada S Tanigawa N Okuda Y Kobayashi M Koyama T 《Cardiovascular and interventional radiology》1999,22(2):155-158
Four patients were treated by placement of an expandable metallic stent (two Gianturco Z-stents, two Ultraflex stents) for malignant colorectal strictures. All four patients were able to defecate after stent placement. Stent migration was recognized in one patient. Two patients suffered from tenesmus after stent placement. 相似文献
37.
Because the usual arterial cannulation was not possible, two small infants successfully underwent cardiovascular operation with an arterial cannula in the supraceliac aorta through the gastrohepatic ligament for cardiopulmonary bypass. Follow-up 2.5 years after operation revealed no morbidity. Cannulation of the supraceliac aorta is unusual but should be considered as a valuable surgical option in special cases such as ours. 相似文献
38.
The present study was designed to examine the usefulness of 2,3-dimercaptosuccinic acid (DMSA) for the purpose of reducing cis-diamminedichloroplatinum (DDP)-induced nephrotoxicity and effective clinical use of DDP and safe. The effectiveness of DMSA on the DDP-excretion in rat kidney was observed by measuring the platinum concentration using Atomic Absorption Instrument. Co-administration of DMSA (1.0 or 2.0 mmol/kg) 1 hour after DDP injection (20 mumol/kg) showed more decrease in the platinum concentration than that immediately after DDP injection. The alleviating effect of DMSA on DDP toxicity was evaluated by lipid peroxidation, enzymatic antioxidants, and glutathione levels. The administration of DDP alone caused a significant increase in lipid peroxidation and significant decreases in enzymatic antioxidants and glutathione levels in the kidney. Co-administration of DMSA (2.0 mmol/kg) 1 hour after DDP injection showed the most effective reduction of these enzymatic damages caused by DDP. These findings suggested that the co-administration of DMSA (2.0 mmol/kg) 1 hour after DDP injection leads DDP to effective excrete from renal tissue and suppresses the lipid peroxide reaction and results in reduction of nephrotoxicity. 相似文献
39.
Comparison of low attenuation areas on computed tomographic scans between inner and outer segments of the lung in patients with chronic obstructive pulmonary disease: incidence and contribution to lung function 总被引:5,自引:1,他引:4
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BACKGROUND: The low attenuation areas on computed tomographic (CT) scans have been reported to represent emphysematous changes of the lung. However, the regional distribution of emphysema between the inner and outer segments of the lung has not been adequately studied. In this study the regional distribution of low attenuation areas has been compared by quantitative CT analysis and the contribution of the regional distribution to pulmonary function tests evaluated in patients with chronic obstructive pulmonary disease (COPD). METHODS: Chest CT images and the results of pulmonary function tests were obtained from 73 patients with COPD. The lung images were divided into inner and outer segments in the upper (cranial), middle, and lower (caudal) sections. The percentage ratio of low attenuation area to corresponding lung area (LAA%) was then calculated. The LAA% of each segment was also compared with the results of pulmonary function tests. RESULTS: The mean (SD) LAA% of the inner segment was 39.1 (18.5) compared with 28.1 (13.2) for the outer segment (p<0.0001). Linear and multiple regression analyses revealed that airflow limitation is closely correlated with the inner segment LAA% of the lower lung. In contrast, the carbon monoxide transfer factor is closely correlated with the inner segment LAA% of the upper lung. CONCLUSION: Low attenuation areas on CT scans are more often found in the inner segment of the lung than in the outer segment, and the contribution of the inner segment to pulmonary function tests may be greater than the outer segment. 相似文献
40.