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21.
Repetitive or acute treatment of methamphetamine (MAP) or amphetamine (AMP) induces sensitization to both subsequent challenge treatment of the drugs, and exposure to emotional and physiological stress. In addition, chronic treatment of AMP enhanced DA utilization/release in striatum. Similarly, repetitive exposure to footshock or tail shock stress induces sensitization of noradrenaline or 3-methoxy-4-hydroxyphenylglycol (MHPG) to subsequent mild stress and to small amounts of AMP or MAP injection. Striatum, nucleus accumbens and prefrontal dopaminergic systems have an important role in the development of this sensitization. Immediate early gene (IEG) expression in the hypothalamus, nucleus accumbens and striatum may be involved in this process. Neurobiological vulnerability to schizophrenia may be induced by the interaction of multiple gene disposition and environmental insult, and schizophrenia onset and/or relapse in response to mild, non-specific stress. Stress-sensitive systems therefore are postulated in the pathophysiology of schizophrenia. In this regard, mesolimbic DA systems may be involved in the pathophysiology of schizophrenia. In contrast to MAP- or AMP- and stress-induced sensitization, haloperidol and clozapine induce IEG expression in the caudate-putamen and amygdala. Collectively, MAP- or AMP-induced sensitization may, in part, share an early functional process of neurobiological mechanisms.  相似文献   
22.
Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.  相似文献   
23.
A novel dimeric flavonol glycoside linked through a methylene group, kunzeagin A (1), and six new chromone C-glucosides, kunzeachromones A-F (2-7), were isolated along with seven known compounds from the leaf extract of Kunzea ambigua. The structures of these compounds were elucidated on the basis of spectroscopic analyses and chemical properties. Kunzeachromones A-F provided additional examples of galloylated C-glucosidic chromones occurring in the Myrtaceae. Kunzeagin A (1) and major constituents of this plant (6-C- and 8-C-glucosylchromones and their monogallates) exhibited potent inhibitory effects on activation of Epstein-Barr virus early antigen induced by 12-O-tetradecanoylphorbol 13-acetate in Raji cells.  相似文献   
24.
The present study was undertaken to determine whether or not adrenalectomy influences anesthesia and increase in brain 5-HT induced by pentobarbital and if such is the case, whether or not aldosterone or ACTH inhibit the effect of adrenalectomy. Male Wistar rats were adrenalectomized or sham-operated and injected with aldosterone (20mug5hg i.p.), ACTH (5.0 mg/kg i.p.) or the vehicle (1.0 ml/kg i.p.) everyday for 1 week after a postoperative interval of 3 days. These rats ware given a normal diet and 1% saline approximately 5% glucose solution. Animals were injected with pentobatbital (50 mg/kg i.p.) 18 hr after the last injection of each hormone. It was found that adrenalectomy enhanced "pentobarbital-anesthesia", although there was no such effect in the adrenalectomized rats pretreated with each hormone. Adrenalectomy inhibited an increase of 5-HT in the brain after pentobarbital, but the hormone pretreatment to those rats did not antagonize the inhibition of the 5-HT increase.  相似文献   
25.
Licochalcone A, 3-a,a-dimethylallyl-4,4'-dihydroxy-6-methoxychalcone, from the root of Glycyrrhiza inflata Beta (Leguminosae) (Xin-jiang liquorice) showed anti-inflammatory action towards mouse ear edema induced by arachidonic acid (AA) and 12-O-tetradecanoylphorbol 13-acetate (TPA) by topical application. Anti-tumour promoting action of licochalcone A was also observed in vivo for mouse skin papilloma initiated by dimethylbenz[a]anthracene (DMBA) and promoted by TPA. It inhibited in vitro 32Pi-incorporation to phospholipids in HeLa cells promoted by TPA. A competitive interaction of licochalcone A with the TPA-receptors in the cell membrane has been suggested.  相似文献   
26.
Y Takatsu  R Hattori  K Sakaguchi  Y Yui  C Kawai 《Chest》1985,88(1):147-149
A 19-year-old man with untreated systemic lupus erythematosus had an acute myocardial infarction. A coronary arteriogram five hours after the onset of symptoms revealed total occlusion of the left anterior descending coronary artery. Reperfusion was achieved by coronary thrombolytic therapy with urokinase. Four weeks later, a coronary arteriogram showed only minimal luminal irregularities at the original site of occlusion, where significant reduction in diameter could be induced by ergonovine maleate. This case suggests that coronary arterial involvement in systemic lupus erythematosus may be related to coronary arterial spasm.  相似文献   
27.
Background Oxaliplatin is a newly developed antitumor platinum complex that is known to have low nephrotoxicity. The inhibitory effects of oxaliplatin on several tubular functions were compared with those of cisplatin and carboplatin, using a renal cortical slice system.Methods and results Rat renal cortical slices were incubated with 0.25mM to 2.0mM of oxaliplatin, cisplatin, on carboplatin at 37°C for 120min. Para-amino hippuric acid (PAH) accumulation, gluconeogenesis, and ATP content in the rat renal slices were determined. PAH accumulation was not inhibited by carboplatin, but it was signific-antly inhibited by oxaliplatin and cisplatin. Inhibition of PAH accumulation by cisplatin was greater than that by oxaliplatin. Gluconeogenesis was not decreased by carboplatin, but it was suppressed by oxaliplatin and cisplatin in a dose-dependent manner. The decrease in gluconeogenesis induced by oxaliplatin was significantly greater than that induced by cisplatin. ATP content in the renal slices was decreased by oxaliplatin, cisplatin, and carboplatin to almost the same extent. As an in vivo experiment, 21.6mmole/kg of oxaliplatin, cisplatin, or carboplatin was injected into rats; then blood urea nitrogen (BUN) and serum creatinine were determined on day 4. Significantly elevated levels of BUN and serum creatinine were observed only in the rats injected with cisplatin.Conclusions Oxaliplatin did not cause nephrotoxicity in the in vivo study; however, the nephrotoxic pattern of oxaliplatin observed in the renal cortical-slice system resembled that of cisplatin. The reason why oxaliplatin is less nephrotoxic than cisplatin in vivo could not be fully elucidated in the present experiment using the renal cortical-slice system.  相似文献   
28.
Owing to the disparity between the supply of kidney donors and demand, the use of organs from older deceased donors was initiated in recent years. The potentially poor outcome of these grafts is a major concern. This retrospective study compares graft and patient 1-year survivals between recipients from expanded-criteria donors (ECD; n = 30) and standard-criteria donors (SCD; n = 104). Rates of delayed graft function (DGF), acute rejection (AR), and chronic injury in the pre-implantation biopsy were also assessed. Increasing donor age was associated with increased rates of DGF, and DGF correlated with AR. Cold ischemia time >30 hours was associated with worse graft outcomes. Induction with Simulect correlated with better patient survival compared with Timoglobulina. Chronic injury pre-implantation biopsy correlated with worse renal function, but graft survival was similar. Death-censored graft survival at 1 year was 90% and patient survival 82%, and these were similar in ECD and SCD recipients. Selection of transplant candidates for ECD kidneys must be performed with caution. One-year graft survival was similar to that of SCD kidneys, but kidney function was worse during the same period. This may result in poorer graft survival over longer follow-up.  相似文献   
29.
Annals of Nuclear Medicine - Amyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of...  相似文献   
30.
PURPOSE: Strontium-89 chloride (89Sr) is a new radiopharmaceutical that provides effective pain relief for metastatic bone lesions, and is expected to be available soon in the palliative management for metastatic bone pain in Japan. Because of relatively long physical half life (50.5 days), 89Sr may affect to the radioactive draining-water system by exceeding the limits of activity concentration for radioactive drain. In this article, the influence of 89Sr use on the radioactive drainage system was simulated. METHODS: The standard tank capacity of drainage and draining frequency was determined from the results of questionnaire carried out for the nationwide medical and research institutes where radioisotope treatment are performed. On the assumption that 89Sr of 148 MBq for one therapy was used twice a week and several common radionuclides were used as the same activity as used at Chiba Cancer Center, the influence of 89Sr was estimated. The calculation was performed using the activity contamination ration into the draining-water system of each radionuclide of 0.01, which was legally determined. RESULTS: The simulation revealed that the sum of the contamination ratios of individual radionuclides exceeded a legal value of 1.0 in standard drainage with the capacity of 5 m3 and 10 m3 and draining frequency of 7 times per year. The actual contamination ratios of common radiopharmaceuticals measured at Chiba Cancer Center ranged from 1/100 to 1/1000 of the legal values. CONCLUSION: It is necessary that the legal value of activity contamination ratios into the draining-water system should be reassessed before starting 89Sr therapy.  相似文献   
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