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991.
Ultraviolet-B and PUVA share several biological events with phorbol ester tumor promoters. The effects of ultraviolet-B irradiation and topical PUVA treatment on ornithine decarboxylase activity, DNA synthesis, and protein kinase C activity, which are known to be induced or activated by phorbol ester tumor promoter, were investigated in hairless mouse skin. Ornithine decarboxylase activity was remarkably enhanced by ultraviolet-B and PUVA. Although PUVA did not affect DNA synthesis significantly, ultraviolet-B stimulated epidermal DNA synthesis approximately 5-fold over control values at 48 h. However, unexpectedly, neither cytosolic nor membrane-bound protein kinase C activity showed any change during the 2 h after either treatment. These results suggest that the protein kinase C system is not involved in the initial signal transduction system of ultraviolet-B or PUVA, unlike the case with phorbol ester tumor promoter.  相似文献   
992.
No comprehensive study on special treatment facilities for alcoholics in Japan has been reported. We conducted a questionnaire survey of alcoholism treatment wards, alcoholism treatment rooms, special outpatient clinics for alcoholics and halfway houses for alcoholics. The survey covered nearly all of such facilities in Japan. The results of the survey revealed the following characteristics: (1) The number of such facilities has increased rapidly in recent years; (2) the facilities are concentrated in cities; (3) the great majority of the facilities are privately operated; (4) many of the facilities are associated with psychiatric departments; and (5) there are very few facilities exclusively for female alcoholics. The most fundamental and important point is that the number of special treatment facilities for alcoholics is insufficient to meet current needs. These facilities have not diversified sufficiently to address adequately the changing needs of Japanese alcoholics.  相似文献   
993.
Data from a joint Japan-U.S. collaborative study were examined to determine the relationship of acculturation to drinking attitudes among Japanese in Japan and Japanese Americans in Hawaii and California. Drinking attitudes (i.e., self-reported acceptable or appropriate levels of drinking) among ethnic groups differed significantly for the nine situations studied: (1) at a bar with friends, (2) at a party at someone else's house, (3) as a parent, spending time with small children, (4) during working hours, (5) visiting in-laws, (6) with friends at home, (7) with friends after work, (8) with people at sports events and (9) before driving a car. Factor analysis was used to determine the differences in drinking attitudes among these ethnic groups. Japanese and Japanese Americans differentiated drinking situations into different categories. The major difference between the two groups was that the Japanese associated spending time with small children with a situation appropriate for drinking, such as being with friends at home, whereas Japanese Americans associated spending time with small children with a situation inappropriate for drinking, such as before driving.  相似文献   
994.
Sixteen beagles were allocated into 4 groups, each group consisting of 2 males and 2 females, which were injected sc with 1,3,5 or 7 mg paraquat/kg. The beagles were observed for 2 w after the administration. At the end of the observation period all the dying and surviving dogs were studied pathologically. The LD50 was calculated as 1.8 (1.0-6.1) in males and 3.5 (2.4-10.1) mg/kg in females. Clinical laboratory tests showed increases in segmented neutrophils and monocytes, decreases in lymphocytes, slight decreases in chloride, moderate increases in BUN, GOT, GPT and phospholipids, slight increases in uric acid, total protein, creatine, total cholesterol and total bilirubin, and prolonged prothrombin times. Marked edema, congestion and hemorrhage of lungs, as well as slight congestion in various organs, were observed grossly. In histopathological examination, marked pulmonary hemorrhage and congestion, fibroblast-like cells in alveolar septa, breakdown of alveolar walls, thickening of alveolar walls and pleura, mild congestion and degeneration of the liver, and mild degeneration of renal tubules were observed. The cause of death was respiratory distress and renal failure. The surviving animals had mild atelectasis of the lungs. Electromicroscopic examination on the surviving animals revealed the appearance of spindle-shaped cells, proliferation of type II alveolar cells and fibroblasts, mitosis of fibroblasts, and abundant collagen fiber in the lung, calcium deposition, stratification and thickening of basement membranes, and localized necrotic epithelial cells in the proximal tubules of kidneys, and stratification of intramitochondrial cristae of the liver. Pulmonary fibrosis in the switchover stage was present with participation from type II alveolar cells, fibroblasts and myofibroblasts.  相似文献   
995.
996.
Gomishi and Shosaiko-to were administered to the rats at a dose of 10-100 mg/kg daily for 2 weeks, and their effects on lipid peroxidation of rat brain were compared with that of alpha-tocopherol. Administration of Gomishi and Shosaiko-to showed almost the same suppressive action on the lipid peroxidation. Gomishi and Shosaiko-to exhibited a radical-trapping action on a stable free radical, 1, 1-diphenyl-2-picrylhydrazyl (DPPH), which was estimated photometrically. The effects of Gomishi or Shosaiko-to at concentrations of 10(-3) to 10(-5)g/ml on lipid peroxidation of rat brain homogenates were investigated. The lipid peroxidation was inhibited by the addition of these drugs, and the suppressive effect was also dependent on the concentration. These suppressive effects with Shosaiko-to were stronger than those of Gomishi. These results suggest that the radical trapping action of Gomishi or Shosaiko-to is the likely mechanism suppressing brain lipid peroxidation; Particularly, the suppressive effect on the brain's lipid peroxidation by Shosaiko-to is at least in part due to its radical trapping action and inhibition of O2-. production.  相似文献   
997.
The Tac antigen (p55, CD25) is a 55 kDa glycoprotein that binds interleukin 2 at low affinity (Kd congruent to 10-50 nM). Expression of the Tac antigen is induced in the activated human T cells to constitute the functional, high-affinity IL-2 receptors (IL-2Rs) (Kd congruent to 10 pM) in conjunction with p70-75. A monoclonal antibody, anti-Tac, recognizes this molecule and inhibits the binding of IL-2 to both high- and low-affinity IL-2Rs. This observation indicates that IL-2 and anti-Tac binding sites are located close to each other within the Tac molecule. In this report, by utilizing a novel approach, we selected cDNAs encoding the Tac antigen variants whose reactivity with anti-Tac is greatly reduced, while retaining their IL-2 binding activity. Each of the mutant cDNAs contained a point (G----A) mutation resulting in an amino acid substitution at the particular amino-terminal portion of the Tac molecule (Asp-4). These results demonstrate that N-terminal amino acid Asp-4 is involved in the epitope recognized by anti-Tac, and that IL-2 binding site and anti-Tac binding site are structurally separable from each other in the Tac molecule.  相似文献   
998.
Serum zinc and copper levels were evaluated in patients with gastric cancer who had undergone gastrectomy. These patients were divided into two age categories; namely, the aged group, comprising 39 patients over the age of 70 years, and the younger group, comprising 23 patients younger than 50 years. The data before and after surgery were compared between the two groups. Serum zinc levels in the aged group were significantly lower than those in the younger group, both before and after surgery. Serum copper levels, however, did not differ significantly between the two groups. The serum Cu/Zn ratio was also analyzed according to the histological stages of cancer (stages I to IV), and compared between the two ageclassified groups. The aged group showed a higher Cu/Zn ratio at all stages, whereas in the younger group, the ratio was significantly higher at stage IV than in the earlier stages. Preoperative serum zinc, copper, and the Cu/Zn ratio were studied in relation to the complication of anastomotic leak after surgery. The Cu/Zn ratio in the aged patients with this complication was significantly higher than that in the aged patients without it. These results suggest that the Cu/Zn ratio may be an important factor in determining nutritional parameters in the aged.  相似文献   
999.
Semiischemic forearm exercise tests were carried out in two patients with idiopathic hypoparathyroidism who had muscle cramps and high serum levels of creatine kinase. Although cubital venous lactate levels increased normally after forearm exercise, venous ammonia and hypoxanthine were greatly increased. The abnormal responses of ammonia and hypoxanthine were normalized 3 months after treatment with 1 alpha-hydroxyvitamin D3. These findings suggest that excess purine degradation occurred in exercising muscles of patients with idiopathic hypoparathyroidism.  相似文献   
1000.
The effect of hypermagnesaemia on serum levels of immunoreactive calcitonin was studied in normal human subjects. After iv administration of magnesium sulphate over 120 min, the mean (+/- SEM) serum magnesium concentration rose from the baseline level of 0.9 +/- 0.1 to 2.6 +/- 0.3 mmol/l (P less than 0.01), and thereafter remained higher than the baseline level. The magnesium infusion caused a significant increase in serum immunoreactive calcitonin levels (P less than 0.01). The rise in serum magnesium concentration was accompanied by a significant decrease in the concentrations of corrected serum calcium and whole blood ionized calcium (P less than 0.01, P less than 0.01 respectively). Our results suggest that hypermagnesaemia causes an increase in serum immunoreactive calcitonin levels in normal human subjects despite a decrease in the concentrations of corrected serum calcium and whole blood ionized calcium.  相似文献   
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