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41.
Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.  相似文献   
42.
五味子中联苯环辛二烯木脂素类化合物的质谱研究   总被引:4,自引:0,他引:4  
翟宏斌  丛浦珠 《药学学报》1990,25(2):110-122
本文通过低分辨和高分辨质谱和亚稳分析,对五味子甲素(schisandrin A,1)等23个从五味子科(Schisandraceae)植物中分离出的联苯环辛二烯木脂素类化合物进行了质谱裂解方式研究,总结了重要的质谱特征,为今后继续研究五味子科植物及类似新化合物的结构测定提供了可靠依据。  相似文献   
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The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality.  相似文献   
44.
Inbred Carworth Farms Nelson (CFN) congenitally hyperlipidemic rats had significantly shorter coagulation and prothrombin times and higher levels of coagulation factors, II, V, VII, VIII, and X than did controls. Conversely, congenitally hypolipidemic rats of the same strain had significantly longer coagulation and prothrombin times and lower levels of factors II, V, VII, X and XII and of blood platelets than did controls. A loop-shaped polyethylene cannula was inserted into the aorta to assess the potential for thrombosis. The hyperlipidemic group obstructed this significantly faster and the hypolipidemic group slower than did the controls. Normal CFN rats made hypertensive by unilateral renal artery clip developed hypertension together with significantly elevated serum cholesterol and factor VII and X levels. Rhesus monkeys with diet-induced hyperlipidemia showed shorter prothrombin times and higher factor X levels than did controls on normal diet. By selective breeding, two groups of squirrel monkeys were obtained. Both groups had similar serum cholesterol levels on a normal diet but one group (hyperresponders) showed higher serum cholesterol levels on a cholesterol-containing diet than did the other (hyporesponder) group. Both groups showed significantly elevated levels of factors II, V, VII, IX and X on a cholesterol-containing diet. There was good correlation between the levels of many coagulation factors and serum cholesterol in both rats and monkeys. If thrombosis is important in the genesis of atherosclerosis, these findings could indicate that elevation of plasma lipids may play a role, via the coagulation pathway, in the production of human vascular disease.  相似文献   
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用放射配体受体结合法测定表明:克塞平对多巴胺D_1受体的亲和力较异戊塞平高近20倍。两药对其它各受体的亲和力差別不大。慢性给药后,异戊塞平和克塞平均能使大鼠脑皮层5-HT_2受体的密度显著下降,而亲和力变化不明显。这种下调5-HT_2受体的作用发生在给异戊塞平后1~2周之间,给克塞平后的2~3周之间。慢性给药3周,异戊塞平和克塞平均未使大鼠脑皮层的β受体密度及亲和力产生显著变化。  相似文献   
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As the numbers of military personnel participating in the wars in Afghanistan and Iraq continue to grow, the percentage of individuals who return with both a traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) also increases. Although there appears to be significant overlap in the symptoms resulting from PTSD and TBI, the best course of treatment remains an area of controversy. The authors present initial findings from a Veterans Administration residential program for comorbid PTSD and TBI. Forty-two participants completed a program comprising psychoeducational groups and cognitive skill building that was augmented with a modification of standard cognitive processing therapy. The results suggest that residential programs that incorporate this form of cognitive therapy can anticipate meaningful participation from patients, and that it may be an effective approach to treat PTSD in individuals with a history of TBI.  相似文献   
50.

Background  

This study evaluates the existence of numerical alterations of chromosome 17 and TP53 gene deletion in gastric adenocarcinoma. The p53 protein expression was also evaluated, as well as, possible associations with clinicopathological characteristics.  相似文献   
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