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61.
Rats were reared from weaning (21 days of age) either in isolation or in social groups of five for 30 days and were then tested for spontaneous locomotor activity and 7 days later for 5-hydroxytryptamine (5-HT) agonist-induced behaviour. Isolation-reared animals displayed locomotor hyperactivity when placed in a novel environment. 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) (2 mg/kg IP) and 8-hydroxy-2-(di-n-propyl-amino) tetralin (8-OH-DPAT) (0.32 mg/kg SC) elicited various components of the 5-HT behavioural syndrome in both groups of animals, with forepaw treading and flat body posture being significantly more pronounced in isolation-reared animals. 1-(2,5-Dimethoxy-4-iodophenyl)-2-aminopropane (DOI) (2.5 mg/kg IP), a 5-HT2 selective agonist, produced a significantly greater number of back muscle contractions in isolation-reared animals but there was no difference between the two groups in the number of wet-dog shakes produced. Forepaw treading and flat body posture are thought to be mediated by 5-HT1A receptor activation, and stimulation of this receptor by either 5-MeODMT or 8-OH-DPAT produced greater responding in isolation-reared rats, suggesting supersensitivity of the post-synaptic 5-HT1A receptor. Wet-dog shakes are thought to be mediated by 5-HT2 and other (none-5-HT) receptors while back muscle contractions have been shown to be mediated by 5-HT2 receptors, indicating that there is also an increase in 5-HT2 receptor responsiveness in the socially-isolated animals. In general, the results indicate post-synaptic 5-HT receptor supersensitivity in isolation-reared rats and these receptor changes may be involved in the behavioural profile observed in such rats.  相似文献   
62.
神阙穴敷贴对原发性骨质疏松症骨钙素的影响   总被引:5,自引:0,他引:5  
目的 观察神阙穴贴补血益精透皮贴对原发性骨质疏松症骨钙素 (BGP)的影响。方法 选择原发性骨质疏松症患者130名 ,分神阙穴贴药组 (补血益精穴位透皮贴剂 )、西药组 (羟乙磷酸钠片 )、中药组 (补血益精药丸 )、空白对照组。结果和结论 穴位敷贴组能显著提高骨钙素 (7.69± 1.65 )。穴位敷贴组与中药组 (7.82± 0 .99)和西药对照组 (7.13± 0 .89)对原发性骨质疏松症的骨钙素调整作用基本一致 (P>0 .0 5 )。  相似文献   
63.
目的观察葡萄糖对豚鼠心室肌细胞膜APD,IK1,IK,ICa-L的影响.方法采用全细胞膜片技术记录单个豚鼠心室肌细胞膜的动作电位时程和离子电流.比较0、10和20mmol·L-1葡萄糖对心室肌细胞跨膜离子电流的作用.结果(1)与10 mmol·L-1葡萄糖相比,0和20mmol·L-1均可使豚鼠心室肌细胞的APD缩短(P<0.05);(2)在细胞外葡萄糖浓度为10 mmol·L-1时,内向整流钾电流IK1的电流密度最大,标准化I-V曲线显示0和20mmol·L-1葡萄糖均可抑制IK1,并使I-V曲线左移,其翻转电位从-72.4移至-64.6 mV;(3)与mmol·L-1葡萄糖相比,0和20mmol·L-1葡萄糖均可增加ICa-L的电流幅度和电流密度.当钳制电位为10 mV,细胞外葡萄糖浓度为0 mmol·L-1时,ICa-L的电流密度为(-8.03±0.82)pA/pF(n=8),而10mmol·L-1和20mmol·L-1葡萄糖分别使电流密度增加为(-5.45±0.67)pA/pF和(-6.50±0.56)pA/pF;(4)当钳制电压为 70mV,细胞外葡萄糖浓度为0、10和20 mmol·L-1时,IK的电流密度分别为(18.96±2.86)pA/pF,(8.66±1.87)pA/pF,(15.32±3.12)pA/pF.结论细胞外不同浓度的葡萄糖可使豚鼠心室肌细胞APD,IK1,IK,ICa-L发生改变.细胞外葡萄糖浓度为0和20mmol·L-1对细胞膜离子电流产生相似的影响.  相似文献   
64.
65.
Despite advancements in endoscopy and pharmacology in the treatment of peptic ulcer disease the overall mortality has remained constant at 10% for the past four decades. The aim of this study was to determine the age, gender, racial distribution, incidence and causes of endoscopically diagnosed cases of upper gastrointestinal (UGI) bleeding to summarise treatments undertaken and to report their outcome. A prospective study of UGI bleeding in 128 patients was performed in two surgical wards of Kuala Lumpur Hospital, involving both elective and emergency admissions. The study group comprised of 113 (88.2%) males and 15 (11.7%) females. The mean age was 51.9 years (range 14 to 85 years) and 37.5% (48 of 128 patients) were older than 60 years. The Indian race was over-represented in all disease categories. Smoking (50.1%), alcohol consumption (37.5%), non-steroidal anti-inflammatory drugs (NSAIDs) (17.2%), traditional remedies (5.5%), anti-coagulants (2.3%) and steroids (0.8%) were among the risk factors reported. Common presenting symptoms and signs included malaena (68.8%), haematemesis (59.4%) and fresh per rectal bleeding (33.6%). The commonest causes of UGI bleeding were duodenal ulcer (32%), gastric ulcer (29.7%), erosions (duodenal and gastric) (21.9%), oesophageal varices (10.9%) and malignancy (3.9%). UGI bleeding was treated non-surgically in 90.6% of cases. Blood transfusions were required in 62.6% (67/107) of peptic ulcer disease patients. Surgical intervention for bleeding peptic ulcer occurred in around 10% of cases and involved under-running of the bleeding vessel in most high risk duodenal and gastric ulcer patients. The overall mortality from bleeding peptic ulcer disease was 4.7%. Six patients died from torrential UGI haemorrhage soon after presentation, without the establishment of a cause. Active resuscitative protocols, early endoscopy, more aggressive interventional therapy, early surgery by more senior surgeons, increasing intensive care unit beds and more active participation of multidisciplinary teams in co-ordinating management are among remedial measures advocated. Broader educational preventive strategies should target the causes of UGI bleeding.  相似文献   
66.
目的:探讨药食两用中药复方治疗绝经期综合征的作用机理。方法:以去卵巢大鼠为动物模型,已烯雌酚片为阳性对照药物,采用放射免疫测定法观察该复方对血清E2,FSH,LH,T,P,T3,T4及TSH等激素水平的影响。结果:与去卵巢空白对照组比较,该中药复方能升高血清E2值,降低血清FSH,LH,T3,T4值,差异均有显著性(P〈0.05)。结论:该中药复方能多途径调节卵巢大鼠生殖内分泌功能,改善甲状腺功能。提示其能够稳定机体内环境,缓解绝经期综合征症状。  相似文献   
67.
通过回顾人类禽流行性感冒(流感)疫苗的研究进展,展望疫苗的使用前景,探讨可能存在的问题。综述人类禽流感疫苗的研究现状,提出:基因工程疫苗是人类禽流感疫苗的发展方向,但在疫苗从实验室走向使用的过程中仍存在一些问题。为安全、有效、快速应对下一次疫情,应全面评估疫苗安全性,正确面对成本-效益问题,从法律、人力、物力、资金和技术层面支持疫苗研究、生产,提高疫苗生产力,正确评价疫苗的适用人群。  相似文献   
68.
关于我国公共卫生体系建设现状及对策的思考   总被引:1,自引:0,他引:1  
公共卫生问题直接关系到群众的身心健康,特别是全球化进程的加快,食品卫生、疾病控制等问题是各国共同面临的问题。作者通过对奥地利卫生管理、体系建设、食品安全等方面的考察,进行分析、思考,对我国卫生体制改革提出了建议。作者认为,深化卫生改革,要进一步加强食品卫生监督执法,要重视和加强职业卫生,要加强医疗救治和医疗机构监督管理,要进一步完善社会医疗保险体系,要加强卫生管理理论的培训。  相似文献   
69.
松果菊润喉片的免疫药理学研究   总被引:1,自引:0,他引:1  
目的 观察松果菊润喉片对小鼠免疫功能及其化痰的影响。方法 进行免疫及化痰实验。结果 松果菊润喉片能增强小鼠腹腔巨噬细胞碳粒廓清速度,促进抗体(溶血素)水平的产生,促进二硝基氯苯所引发的迟发性变态性反应的足趾肿胀;对气管黏膜排泄酚红有明显促进作用。结论 松果菊润喉片有促进排痰、提高机体免疫功能的作用。  相似文献   
70.
Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk.  相似文献   
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