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51.
Age- and sex-related differences in the nerve growth factor distribution in the rat brain. 总被引:2,自引:0,他引:2
Levels of the nerve growth factor (NGF) have been measured in various brain regions of young and aged male and female rats of Wistar strain by means of a highly sensitive two-site enzyme immunoassay system for beta-NGF. Among the ten regions examined, the amount of NGF per wet weight of tissue was found to be highest in the hippocampus, irrespective of the sex and age. The NGF concentration in the hippocampus of female rats at 3 months of age was comparable to that of same aged males. Further, there was no significant difference in the NGF levels of the hippocampus between young and age males. However, the NGF level was significantly lower in aged females as compared to that in 3- or 4-month-old females, and hence the marked male-female difference was found in the NGF levels in aged Wistar rats. 相似文献
52.
53.
The characteristics of a glial Na+,K+-pump dependent on extracellular K+ within epileptogenic cortex were studied electrophysiologically, biochemically and histochemically in vitro using slices from cobalt-induced epileptogenic cortex of rat. When the extracellular K+ concentration ([K+]o) was varied between 4 and 40 mM, the mean slope of membrane potential plotted against [K+]o was about 57 mV in glia from the normal cortex (tissue A) and about 44 mV in glia from the epileptogenic cortex (tissue B); whereas no significant difference in the resting membrane potential of these tissues was observed. In glia from tissue B, a marked transient hyperpolarization above control level was caused by replacement of elevated [K+]o with the normal medium. Ouabain abolished these phenomena observed in glia from tissue B, but had no effect on the membrane potential during normal [K+]o. Reduction of extracellular Na+, Ca2+ and Cl− did not significantly affect the membrane potential of glia from either tissue. In tissue A, the cells marked by intracellular injection of horseradish peroxidase after intracellular recording were protoplasmic astrocytes; in tissue B, fibrous astrocytes with abnormal processes predominated. K+-dependent stimulation of Na+,K+-ATPase activity of the astrocyte-enriched fraction and its membrane preparation from tissue B was much larger than that from tissue A. A certain amount of the reaction product of K+-pNPPase activity was seen on glial plasma membrane within tissue B but not on that from tissue A. The above findings suggest that a glial Na+,K+-pump within actively firing epileptogenic cortex may be modified to increase in its activity. 相似文献
54.
K Koshimura T Kato I Tohyama S Nakamura M Kameyama 《Journal of the neurological sciences》1986,76(2-3):143-150
The maximum activity of choline acetyltransferase (ChAT), the affinity for choline or acetyl-CoA and the isozyme pattern in the cerebral cortex of 5 cases of Alzheimer type dementia (ATD) and 6 age-matched control subjects were examined post-mortem. Maximum activities of ChAT were estimated in 5 cerebral cortical areas of Brodmann: 4, 7, 10, 17 and 22. A significant reduction in maximum activities of ChAT was found in all cortical areas for the cases of ATD. The affinity for choline or acetyl-CoA was measured in the frontal cortex (Brodmann's areas 4 and 6) and in the temporal cortex (Brodmann's areas 21 and 22). The affinity was significantly decreased in both cortices of demented patients. A significant correlation was observed between maximum activity of ChAT and the affinity for choline or acetyl-CoA. The isozyme pattern obtained by column chromatography on Sephadex G-200 was similar to that obtained by centrifugation on a sucrose density gradient. The isozyme pattern of ATD was different from that of the control subjects. These results suggest qualitative as well as quantitative abnormalities in the ChAT in autopsied brains of ATD. 相似文献
55.
Eighteen patients received gastrectomy for primary cancer of the gastric remnant were studied clinico-histopathologically. Gastric ulcer had been the most common condition requiring previous gastric surgery, and Billroth II resection had been the most often employed procedure. The cancer of the gastric remnant was in an advanced stage in all patients. Tumors were detected in the sutured or anastomosed region (especially the latter) of the remnant stomach in a great majority of the patients studied. In spite of combined resection of the adjacent organs, such as spleen, pancreas and colon in most patients, curative resection could be done in only a half of them and the prognosis was poor in general. These observations seem to stress the importance of following up gastrectomized patients periodically and precautiously by endoscopic examination with multiple biopsy, because early detection of cancer of remnant stomach may lead to improvements in therapeutic results. 相似文献
56.
57.
To clarify the role of serotonin in cerebral ischemia, we examined the effects of selective serotonin reuptake inhibitors, citalopram and clomipramine, on ischemic neuronal damage in the gerbil. Pretreatment with citalopram (40 mg/kg i.p.) and clomipramine (20 mg/kg i.p.) protected against neuronal destruction of hippocampal CA1 pyramidal cells following 5 min of forebrain ischemia. Furthermore, microdialysis assays showed that a striking increase in extracellular excitatory amino acid levels during ischemia was significantly inhibited by pretreatment with citalopram and clomipramine. However, citalopram (40 mg/kg i.p.) did not alter the extracellular amino acid concentrations in normal gerbils. Thus, serotonin reuptake inhibitors have a protective effect against ischemic neuronal damage. Furthermore, the present result suggests that the protective effect is mediated through prevention of the accumulation of extracellular excitatory amino acids during and after ischemia. 相似文献
58.
From 1965 to 1968, 7716 Japanese-American men were examined and tested for serum cholesterol. After 22 years, 1380 incident cancer cases were identified. Of the site-specific cancers, only colon cancer cases had a significantly lower mean serum cholesterol value than that of noncases (213.0 mg/dl vs 219.0 mg/dl). When the study subjects were separated into either a low, middle or high group, based on their serum cholesterol values, there was a significant inverse trend for cases of oral/pharyngeal/esophageal cancer combined. The association was present for cases diagnosed within 10 years of examination (p = 0.012), but not for cases diagnosed after 10 years. This suggests that the inverse association is due to the metabolic effects of undiagnosed oral/pharyngeal/esophageal cancer upon serum cholesterol levels. These results are discussed in relation to other studies on serum cholesterol. 相似文献
59.
M Kato 《Nihon Jibiinkoka Gakkai kaiho》1991,94(7):990-997
To examine the difference between response of nasal mucosa to specific antigen and that to non-specific stimulus in the same patient, specific nasal provocation was performed using the house dust antigen disk while nasal respiratory resistance was continuously measured by Rhinograph. On the other hand, non-specific nasal provocation was performed with inhalation of methacholine while nasal respiratory resistance was continuously measured with Astograph. Thereafter the resulting response curves were analyzed. Subjects were 12 males and 9 females, who had nasal obstruction, watery rhinorrhoea and sneeze, and were proved to have allergic rhinitis by house dust. To analyze specific response curve, primary nasal respiratory resistance (Rrs.N), reacting time (Ta) and slope signifying increase of nasal respiratory resistance (delta Rrs.N) were used as parameters. To analyze non-specific response curve, primary nasal respiratory resistance (Rrs.N.cont), minimum dose of methacholine that caused an increase of nasal respiratory resistance (Dmin.N) and slope signifying increase of nasal respiratory resistance (Sd.N) were used as parameters. Ta and Dmin.N reflect sensitivity of nasal mucosa. Their values become smaller, it means sensitivity of nasal mucosa becomes higher. Delta Rrs.N and Sd.N reflect reactivity of nasal mucosa. Their values become larger, it means reactivity of nasal mucosa becomes larger.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
O Shinohara S Kato H Yabe M Yabe C Kubota R Mitsuda M Kimura 《The American journal of pediatric hematology/oncology》1991,13(3):263-268
Growth of the patients with hematological malignancies, aplastic anemia, Fanconi's anemia, and Wiscott-Aldrich syndrome who had been treated with bone marrow transplantation (BMT) was studied. Fourteen out of 21 patients showed suppression of linear growth after BMT. Recovery of the growth velocity after 1-2 years tended to occur if BMT was performed at younger age. Six of eight patients with chronic graft-versus-host-disease (CGVHD) had impaired growth after BMT, whereas eight of 13 (61%) without CGVHD did. Provocative tests for growth hormone (GH) performed 5-72 months after BMT revealed three boys who showed poor response to more than two different stimuli. Two of these three boys had prolonged suppression of growth. Neither the age at BMT, difference in disease, nor presence of posttransplant growth retardation gave significant difference in the response of GH to provocative tests. It was concluded that approximately two-thirds of marrow-grafted children experienced transient decrease in growth velocity after BMT. 相似文献