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71.
头低位模拟失重状态对前庭功能的影响 总被引:4,自引:1,他引:3
为研究头低位模拟失重对运动病症状、垂直视动眼震(VOKN)及体液重新分配的影响,在头低位-10°的模拟失重状态下,采用大视野的垂直视动刺激,观察18名正常人的运动病症状、VOKN、激素(AVP、VIP、CORT、ALDO)的反应特点。结果表明,头低位-10°状态下的大视野垂直视动刺激可以诱发出明显的运动病症状,头低位-10°的垂直视动刺激比坐位更容易诱发运动病。坐位状态VOKN慢相速度有明显的方向性不对称,敏感组VOKN方向性不对称有显著差异(P<0.05)。头低位-10°时VOKN的不对称现象不明显,向下方向运动的VOKN慢相速度显著增加。分析指出,头低位-10°状态下垂直视动刺激比坐位和秋千刺激的贡献率大。尿中CORT(皮质醇)在秋千和头低位的垂直视动刺激前后有显著性增加。提示:大视野的垂直视动刺激与头低位-10°两种刺激的结合可能成为预测空间运动病的方法之一. 相似文献
72.
73.
Rajiv Jalan Rebecca Gooday Ronan E. O'Carroll Doris N. Redhead Robert A. Elton Peter C. Hayes 《Journal of hepatology》1995,23(6)
Background/Aims: This study was designed to assess changes in: (a) neuropsychological tests, measures of memory, quality of life and scores for anxiety and depression; (b) liver function tests; and (c) the relationship between these following transjugular intrahepatic portosystemic stent-shunt.Methods: Twenty-nine patients undergoing transjugular intrahepatic portosystemic stent-shunt for recurrent variceal haemorrhage, 12 matched patients with cirrhosis and variceal haemorrhage manage with variceal band ligation and 16 normal controls were studied. Patients in any of the groups who were clinically encephalopathic were excluded from the study. Serial changes in the conventional liver function tests and Indocyanine green clearance, and psychometric function (Hospital Anxiety Depression Scale, Rivermead Behavioral Memory Test, Quality of Life and the memory and reaction sub-tests of the Cambridge Automated Neuropsychological Test Assessment Battery) were measured prior to and 1, 3, 9 and 15 months following transjugular intrahepatic portosystemic stent-shunt.Results: Over a mean follow up of 9.1 months in the transjugular intrahepatic portosystemic stent-shunt group (range 3–28), one patient (3%) developed clinically detectable encephalopathy. Sixty-seven percent of patients with cirrhosis showed evidence of subclinical encephalopathy as compared with the control population. Significant deterioration occurred in the reaction sub-tests of the Cambridge Automated neuropsychological Test Assessment Battery in patients, both in the transjugular intrahepatic portosystemic stent-shunt group and the controls with cirrhosis, during follow up. Transjugular intrahepatic portosystemic stent-shunt was followed by significant deterioration in levels of anxiety and psychological component of the quality of life. The Rivermead Behavioural Memory Test and the memory sub-test of the Cambridge Automated Neurpsychological Test Assessment Battery did, however, improve significantly at 1 and 15 months after transjugular intrahepatic portosystemic stent-shunt, respectively. Serum alanine aminotransferase, bilirubin and indocyanine green clearance deteriorated significantly following transjugular intrahepatic portosystemic stent-shunt (p<0.001, p<0.001 and p<0.0001, respectively). Significant correlation was observed between changes in the indocyanine green clearance and changes in the complex and simple reaction time subtests of the Cambridge Automated Neuropsychological Test Assessment Battery (r=0.6 and r=0.66, respectively).Conclusions: The results of this study showed that about 67% of patients with cirrhosis were subclinically encephalopathic and that temporary deterioration occurred in the Cambridge Automated Neuropsychological Test Assessment Battery during follow up, both in patients having transjugular intrahepatic portosystemic stent-shunt and in the controls with cirrhosis. These parallel the changes in the liver function tests and indocyanine green clearance. Temporary deterioration was also observed in the Quality of Life and Hospital Anxiety Depression Scale in the transjugular intrahepatic portosystemic stent-shunt group, although the measures of memory improved. Further studies should address the biochemical mechanisms of these changes and the role of prophylactic measures. 相似文献
74.
Keith May 《American journal of obstetrics and gynecology》1991,165(6):2000-2002
75.
Attenuation of myocardial injury due to oxygen free radicals(OFR) by pretreatment with OFR or calcitonin gene-related peptide 总被引:3,自引:0,他引:3
目的:研究氧自由基(OFR)及降钙素基因相关肽(CGRP)预处置对OFR所致离体大鼠心脏损伤的拮抗作用.方法:Langendorf法灌流心脏,电解KH液产生OFR.结果:CGRP或OFR预处置减轻OFR所致心脏收缩功能下降,冠脉流量减少和肌酸激酶(CK)释放增加.蛋白激酶C(PKC)抑制剂H7可取消OFR预处置的心脏保护作用(对照组,OFR损伤组,OFR预处置组,H7加OFR预处置组及H7组的CK释放量分别是110±7,215±23,169±14,240±30,113±19U·L-1).结论:OFR或CGRP预处置对OFR所致心肌损伤具有拮抗作用,该作用与PKC激活有关. 相似文献
76.
50例高血压病人ACG和 FDACG 检测的结果显示:高血压病不论舒张压高低或有无心脏增大,均有舒张功能改变,表现为A/EO 比值增高,A_2-dA/dt-min 和A_2O延长。此三项指标的异常出现率分别为40%、30%及14%,三项联合检测其中任何一项异常的出现率为54%。收缩功能无明显改变。治疗显效后,A/EO降低,A_2-dA/dt-min 缩短,说明心功能明显改善。 相似文献
77.
Department of Urology, School of Medicine, Keio University, Tokyo, Japan
Background Conventional therapy for renal cell carcinoma using interferon (IFN) has shown limited antitumor action. The purpose of our study was to investigate synergistic antitumor effects of IFN and 5-fluorouracil (5-FU), and to elucidate the mechanisms of interaction between the 2 agents in mice.
Methods Antitumor effects and biochemical modulation of murine IFN-α/β and 5-FU were determined against the murine renal cell carcinoma cell line, Renca, in vivo. The activity of thymidylate synthetase and thymidine kinase was measured using cytosolic extracts of the tumors.
Results Combination treatment with IFN-α/β and 5-FU produced a significant enhancement of growth inhibition against Renca tumor. Treatment with 5-FU resulted in a 2.7-fold increase in the total amount of thymidylate synthetase and an 11.6-fold increase in the thymidylate synthetase inhibition rate, while the administration of IFN-α/β did not significantly reduce the 5-FU-induced increase in thymidylate synthetase. The administration of IFN-α/β decreased thymidine kinase activity to 65.5% maximally, compared with that in the control mice or the mice treated with 5-FU.
Conclusions The reduction of thymidine kinase caused by treating the mice with IFN-α/β changes the utilization of exogenous thymidine for DNA synthesis, and may represent the mechanism of the additive antitumor effect of the 2 agents, through the suppression of the salvage pathway for deoxythymidine monophosphate induction. 相似文献
Background Conventional therapy for renal cell carcinoma using interferon (IFN) has shown limited antitumor action. The purpose of our study was to investigate synergistic antitumor effects of IFN and 5-fluorouracil (5-FU), and to elucidate the mechanisms of interaction between the 2 agents in mice.
Methods Antitumor effects and biochemical modulation of murine IFN-α/β and 5-FU were determined against the murine renal cell carcinoma cell line, Renca, in vivo. The activity of thymidylate synthetase and thymidine kinase was measured using cytosolic extracts of the tumors.
Results Combination treatment with IFN-α/β and 5-FU produced a significant enhancement of growth inhibition against Renca tumor. Treatment with 5-FU resulted in a 2.7-fold increase in the total amount of thymidylate synthetase and an 11.6-fold increase in the thymidylate synthetase inhibition rate, while the administration of IFN-α/β did not significantly reduce the 5-FU-induced increase in thymidylate synthetase. The administration of IFN-α/β decreased thymidine kinase activity to 65.5% maximally, compared with that in the control mice or the mice treated with 5-FU.
Conclusions The reduction of thymidine kinase caused by treating the mice with IFN-α/β changes the utilization of exogenous thymidine for DNA synthesis, and may represent the mechanism of the additive antitumor effect of the 2 agents, through the suppression of the salvage pathway for deoxythymidine monophosphate induction. 相似文献
78.
G. J. Wiener MD T. M. Morgan PhD J. B. Copper PA W.C. Wu MB BS D. O. Castell MD J. W. Sinclair PA Dr. J. E. Richter MD 《Digestive diseases and sciences》1988,33(9):1127-1133
If 24-hour esophageal pH monitoring is to be a useful diagnostic tool, it must reliably discriminate gastroesophageal reflux patients despite daily variations in distal esophageal acid exposure. To address this issue, we studied 53 subjects (14 healthy normals, 14 esophagitis patients, and 25 patients with atypical symptoms) with two ambulatory pH tests performed within 10 days of each other. Intrasubject reproducibility of 12 pH parameters to discriminate the presence of abnormal acid reflux was determined. As a group, the parameters of percent time with pH<4 (total, upright, recumbent) were most reproducible (80%). Therefore, a subject was defined as having gastroesophageal reflux disease if at least one of these three values were abnormal. Intrasubject reproducibility for the diagnosis of reflux disease was 89% for the entire sample. Among subsets, the reproducibility was 93% for the normals and esophagitis patients and 84% for the atypical symptom patients. Total percent time with pH<4 was the single most discriminate pH parameter (85%) and nearly equaled that of the three combined parameters (89%). The intrasubject variability of this parameter was determined by the mean ±2sd of the relative differences between the two test results for all 53 subjects. Total percent time with pH<4 may vary between tests by a factor of 3.2-fold or less (218% higher to 69% lower). We conclude: (1) ambulatory 24-hr esophageal monitoring is a reproducible test for the diagnosis of gastroesophageal reflux disease; and (2) the large intrastudy variability in 24-hr total acid exposure may limit this test's usefulness as a measurement of therapeutic improvement.Supported, in part, by Public Health Services Grant AM 34200-01A1 from NIADDIK. 相似文献
79.
目的:为寻求肠道G杆菌及弧菌快速鉴定的方法。方法:菌种经增菌及分离培养后,取菌落接种于综合生化培养基,并在综合生化培养基管口悬挂硫化氢和靛基质试纸条。同时以克氏双糖铁培养基作对照,置37℃培养18-24h。取综合生化管培养基,外加测试氧化酶,共获取11项生化指标。结果:对689株不同菌种与综合生化管培养基和常规双糖铁培养的测试结果,符合率为99.97%,(7577/7579)和99.79%(7563/7579)。结论:综合生化管是适合医疗卫生单位微生物实验室的一种快速检验方法。 相似文献