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21.
M. R. Wang C. Y. Chai J. S. Kuof 《Clinical and experimental pharmacology & physiology》1994,21(1):21-29
1. In chloralose-urethane anaesthetized cats, the dorsal cardiovascular reactive area (DCRA) in the parvocellular reticular nucleus dorsomedial to the facial nucleus, and the ventral cardiovascular reactive area (VCRA) ventromedial to the facial nucleus, were stimulated by microinjections of sodium glutamate (100–200 nmol) or electric current. 2. Stimulation of DCRA, with a long latency of 15–20 s, elicited a marked increase of blood flow in the contralateral femoral artery with little change to moderate increase in systemic arterial blood pressure (ABP). In the relatively dorsal portion of DCRA, however, a smaller increase of blood flow in the ipsilateral femoral artery was elicited. 3. On the other hand, stimulation of VCRA with a short latency (3–5 s) evoked an increase of blood flow in both femoral arteries which was more prominent on the contralateral side. The responses were accompanied with decreases in the blood flow of other vascular beds with only a slight increase or minimal change in ABP. 4. The data suggest that DCRA and VCRA are both viscerotopically organized to alter the resistance of individual vascular beds for redistribution of blood flow. 相似文献
22.
Bronwyn A. Kingwell Lisa Krause Stevo Julius 《Clinical and experimental pharmacology & physiology》1994,21(1):31-39
1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator. 相似文献
23.
David Langton Diana Way Lisbeth Trigg Duncan Blake Barry McGrath 《Clinical and experimental pharmacology & physiology》1990,17(3):219-223
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process. 相似文献
24.
K.M. SIVANANDAIAH V.V. SURESHBABU S.C. SHANKARAMMA 《Chemical biology & drug design》1995,45(4):377-379
Deprotection of the tert-butoxycarbonyl group during solid-phase synthesis of peptides can be conveniently and efficiently carried out using a neutral reagent, silicon tetrachloride/sodium iodide (iodotrichlorosilane). This simple and rapid method has been advantageously employed during the solid-phase synthesis of the pituitary hormone, oxytocin. 相似文献
25.
影响脐血IgE值因素的研究 总被引:2,自引:0,他引:2
目的 本研究对影响脐血IgE值的可疑因素进行分析 ,探讨影响儿童食物过敏的可疑因素。方法 选取孕期妇女 10 5名及其所生婴儿 ,采用标准问卷调查获取资料 ,对影响脐血IgE的因素进行分析。 结果 母亲的过敏性疾病史、父亲过敏性疾病史中的皮炎表现型、孕期妇女过敏性疾病发作史、有过敏史妇女孕后期摄入过量的牛奶和鸡蛋均与脐血IgE值的上升有关 ,且上述 5个因素对脐血IgE水平的影响依次降低。 结论 母亲的过敏性疾病史和父亲过敏性疾病史中的皮炎表现型是导致新生儿脐血IgE值升高的主要危险因素 ;同时 ,妊娠期加强对有过敏史妇女的保护 ,防止过敏性疾病的复发 ,在孕后期控制有过敏史妇女牛奶、鸡蛋等大分子食物致敏原的摄入 ,有助于降低脐血IgE值。 相似文献
26.
血瘀证的研究发展脉络与评述 总被引:6,自引:0,他引:6
吴承玉 《南京中医药大学学报》2004,20(3):133-136
主要从4个方面论述了血瘀证50年来研究进展.理论研究,着重从古今文献论述血瘀证定义和含义;客观研究,着重对生理、生化、血液流变学、免疫学、病理学和微循环等方面对血瘀证进行研究;血瘀证的动物模型研究,主要对血瘀证动物模型的建立与造模方法和途径进行研究;诊断标准研究,包括诊断标准、诊断指标的研究。并对上述内容进行了评述,并提出了展望。 相似文献
27.
Luis Hernandez-Garcia Gregory R Lee Alberto L Vazquez Chun-Yu Yip Douglas C Noll 《Magnetic resonance in medicine》2005,54(4):955-964
A new approach to modeling the signal observed in arterial spin labeling (ASL) experiments during changing perfusion conditions is presented in this article. The new model uses numerical methods to extend first-order kinetic principles to include the changes in arrival time of the arterial tag that occur during neuronal activation. Estimation of the perfusion function from the ASL signal using this model is also demonstrated. The estimation algorithm uses a roughness penalty as well as prior information. The approach is demonstrated in numerical simulations and human experiments. The approach presented here is particularly suitable for fast ASL acquisition schemes, such as turbo continuous ASL (Turbo-CASL), which allows subtraction pairs to be acquired in less than 3 s but is sensitive to arrival time changes. This modeling approach can also be extended to other acquisition schemes. 相似文献
28.
D. Rothenbacher M. Weyermann G. Fantuzzi H. Brenner 《Clinical and experimental allergy》2007,37(8):1143-1149
BACKGROUND: Adipokines are involved in the regulation of many inflammatory processes and are present at very high concentrations in cord blood of term infants. OBJECTIVE: We analysed data of a large prospective birth cohort study to examine whether adiponectin and leptin concentration in cord blood are determinants of wheezing disorders in children within the first 2 years of life. METHODS: Seven hundred and forty mothers and their newborns were included in this analysis. Adiponectin and leptin concentrations were measured in cord blood. The cumulative incidence of physician-reported asthma or obstructive bronchitis was recorded during a 2-year follow-up. RESULTS: During the first 2 years of life, asthma or obstructive bronchitis was reported by the caring paediatricians for 157 (19.6%) of the children. We found a strong interaction of cord blood adiponectin and history of atopic disease in the mother with respect to the risk of physician-reported asthma or obstructive bronchitis (P=0.006). Compared with children with cord blood levels in the middle quintile (reference category), the odds ratios for physician-reported asthma or obstructive bronchitis in the bottom quintile and top quintile were 0.14 [95% confidence interval (CI) 0.02-0.90] and 2.12 (95% CI 0.67-6.66), respectively (P for trend=0.0003), among children of mothers with a history of atopy. This association was independent of other established risk factors. Leptin levels in cord blood were not associated with risk of asthma or obstructive bronchitis. CONCLUSIONS: In children of mothers with a history of atopy, concentrations of adiponectin in cord blood could play an important role in determining risk of wheezing disorders in early childhood. 相似文献
29.
AIMS: The efficacy of three education programmes for Type 2 diabetic patients was tested in a randomized trial. A didactic-oriented training programme (treatment A) was compared with a self-management-oriented programme delivered in group sessions (treatment B). The latter programme was compared with a more individualized approach (treatment C). METHODS: One hundred and eighty-one Type 2 diabetic patients (age 55.6 +/- 6.3 years, diabetes duration 6.6 +/- 6.2 years, HbA(1c) 7.8 +/- 1.6%, female 49.7%) took part. Efficacy was assessed 3 months (t1) after baseline (t0) and at a follow-up 15 months (t2) after baseline. RESULTS: The fall in HbA(1c) in treatment B at t1 was sustained at t2 (t0 8.1 +/- 1.8%, t1 7.3 +/- 1.7%, t2 7.4 +/- 1.9%). In treatment A, HbA(1c) was unchanged throughout (t0 7.6 +/- 1.5%, t1 7.5 +/- 1.3%, t2 7.7 +/- 1.7%; treatment A vs. treatment B; P < 0.05). With the more individualized approach of treatment C, there was a fall in HbA(1c) at t1, but this was not sustained at t2 (t0 7.8 +/- 1.6%, t1 7.1 +/- 1.3%, t2 7.6 +/- 1.6%; treatment B vs. treatment C; P = 0.73). There were also significant benefits in treatment B subjects compared with treatment A in further medical (body mass index and fasting blood glucose), psychological (control, irritability and hunger dependency of eating behaviour, and trait anxiety) and behavioural (exercise) variables. There were no significant benefits of the more individualized treatment C compared with group treatment B. No significant differences were found regarding triglyceride levels, high-density lipoprotein, diabetes-related knowledge, negative well-being, urine or blood glucose levels or foot care. CONCLUSION: Self-management training had a significantly higher medium-term efficacy than didactic diabetes education. The group sessions were more effective than a more individualized approach. 相似文献
30.
去除白细胞输血的临床意义 总被引:1,自引:0,他引:1
目的:评估去除白细胞输血的临床应用价值。方法:251例患者接受了去除白细胞红细胞悬液761U,(每人1 ̄8U不等),对其中200U红细胞悬液滤除白细胞前、后分别进行白细胞计数和血红蛋白测定,并对其输血反应进行了观察。结果:发现应用白细胞滤器后,其白细胞数比过滤前显著减低,过滤前、后白细胞数分别为(6.16±1.44)×109/L与(0.12±0.10)×109/L(P<0.01),血红蛋白过滤前、后无显著性差异,分别为:(161.58±23.31)g/L与(157.84±22.35)g/L,P>0.05。251例接受去白细胞受血者均未出现输血反应。结论:白细胞滤器能有效去除白细胞,去除白细胞能减少非溶血性输血反应。 相似文献