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51.
M F Riordan C S Beardsmore A M Brooke H Simpson 《Archives of disease in childhood》1994,70(4):299-304
The relationship was studied between preschool and current respiratory symptoms and cough receptor sensitivity in children. Forty six white children aged 7 years were investigated. They were divided into three groups: (i) healthy children; (ii) children with a history of idiopathic cough; and (iii) children with a history of wheezing. Cough receptor sensitivity was assessed by the inhalation of serially increasing concentrations of nebulised citric acid. The concentration which first induced a cough was the cough threshold and was taken as a measure of cough receptor sensitivity. The cough threshold was unrelated to respiratory symptoms, bronchial responsiveness, parental smoking, and atopic status. A wide variation in cough threshold was seen. Although these results suggest that idiopathic cough is unrelated to cough receptor sensitivity as assessed by the citric acid cough threshold, it is unclear whether threshold measurements are an accurate reflection of receptor sensitivity. 相似文献
52.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
53.
Canine myocardial reperfusion injury: protection by a free radical scavenger, N-2-mercaptopropionyl glycine 总被引:5,自引:0,他引:5
S E Mitsos J C Fantone K P Gallagher K M Walden P J Simpson G D Abrams M A Schork B R Lucchesi 《Journal of cardiovascular pharmacology》1986,8(5):978-988
Oxygen-derived free radicals and their metabolites may contribute to the extension of irreversible cellular injury, which occurs on reperfusion of the previously ischemic myocardium. Therefore, therapy directed against the toxic effects of reactive oxygen species may provide protection to the ischemic myocardium, which undergoes subsequent reperfusion. We evaluated the effectiveness of N-2-mercaptopropionyl glycine (MPG), a free radical scavenger, to limit the extent of irreversible injury resulting from 90 min of ischemia followed by 6 h of reperfusion in a canine model of myocardial infarction. In three groups of dogs, MPG (20 mg/kg) was administered as a constant infusion into the left atrium. Group I received MPG for 2 h, starting 15 min before occlusion of the left circumflex coronary artery and ending 15 min after reperfusion. Group II received MPG for 1 h, starting 15 min before reperfusion. Group III received MPG for 1 h beginning 45 min after reperfusion. Each group was compared with its respective saline control group. Infarct size was reduced by 35% in Group I (32.2 +/- 5.1% vs. 47.7 +/- 3.4% of the area at risk, p less than 0.05) and Group II (31.4 +/- 3.6% vs. 47.5 +/- 5.1% of the area at risk, p less than 0.025) in comparison with the saline treated control animals. In contrast, in Group III infarct size did not differ significantly from the saline-treated control group (45.9 +/- 3.3% vs. 47.7 +/- 3.5% of the area at risk). The percent of left ventricle at risk did not differ among the groups. The beneficial effects of MPG could not be explained on the basis of hemodynamic differences. In addition, MPG did not influence regional myocardial blood flow. In vitro studies indicated that MPG effectively scavanges O2- generated by the hypoxanthine-xanthine oxidase reaction, as well as by PMA-activated polymorphonuclear leukocytes. Based on these observations, we propose that MPG exerts its beneficial effects by protecting against free radical-mediated damage during the early phase of reperfusion. 相似文献
54.
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56.
Distraction osteogenesis in the Cbfa-1+/- mouse. 总被引:2,自引:0,他引:2
S Isefuku C J Joyner A A C Reed A H R W Simpson 《Journal of orthopaedic research》2004,22(6):1276-1282
57.
OBJECTIVE--To describe the characteristics of wheeze and its relation with doctor diagnosed asthma in children aged 5 years and under. DESIGN--Questionnaire survey of population based random sample of children registered on Leicestershire Health Authority's child health index for immunisation; questionnaire completed by parents. SUBJECTS--1650 white children born in 1985 to 1989 who were surveyed in 1990. MAIN OUTCOME MEASURES--Age distribution, severity, precipitants, seasonal characteristics, and diurnal variation of wheeze, family history of asthma/atopy, and their association(s) with doctor diagnosed asthma. RESULTS--There were 1422 replies (86.2%). Two hundred and twenty two (15.6%) were reported to have wheezed and of these 121 (8.6%) had formally been diagnosed as having asthma. More than 80% of the former had recurrences of wheeze and 40% (72) had three or more episodes in the preceding 12 months. Age, number of episodes per year, the severity of shortness of breath with attacks, and precipitants other than colds were the major factors determining the probability that a wheezy child will be diagnosed as having asthma. The data also suggest that despite the strong association of symptom based criteria with the label asthma, asthma was not diagnosed by these same severity criteria in one quarter of cases. CONCLUSIONS--Clinical and physiological follow up studies of children identified as asthmatic by the above criteria during the preschool years should validate or refute the predictive value of these measures of wheeze severity. 相似文献
58.
59.
Raoul JL; Bourguet P; Bretagne JF; Duvauferrier R; Coornaert S; Darnault P; Ramee A; Herry JY; Gastard J 《Radiology》1988,168(2):541-545
Biodistribution of iodine-131-labeled Lipiodol Ultra-Fluide (I-131 LUF) injected into the hepatic artery was studied scintigraphically in 47 patients with hepatocellular carcinoma (n = 23), hepatic metastases (n = 14), or normal livers (n = 10). The investigation was extremely well tolerated. I-131 LUF concentrated mainly in the liver (L) and the lungs (l), with L/L + l activity ratios greater than 75% for all three groups of patients. I-131 LUF distribution was homogeneous in normal livers and heterogeneous in cirrhotic livers. I-131 LUF concentrated in the tumor with a tumorous (T) to nontumorous (NT) activity ratio (T/NT) of 4.3 +/- 3.6 for hepatocellular carcinoma and 2.4 +/- 0.7 for hepatic metastases. The effective half-life of I-131 LUF is more than 4.5 days for the three groups. It was eliminated mainly through the urine. Clearance from tumor is slower than from normal liver, as shown by the increase in T/NT at day 18. Biodistribution did not change in patients who had a second injection, which indicates that there is no saturation phenomenon. The results of this study suggest that LUF may be considered as a potential carrier vehicle for therapeutic agents. 相似文献
60.
L Hoffman-Goetz B MacNeil Y Arumugam J Randall Simpson 《International journal of sports medicine》1992,13(2):167-171
Acute exercise and exercise conditioning have been shown to affect the activity of natural killer (NK) cells as well as the growth of experimentally induced tumors in animals. Since psychosocial factors are also known to alter NK activity and tumor growth, isolation, a known psychosocial stressor of mice, was also investigated to see if housing condition could alter exercise-induced changes in NK cell activity and tumor growth. NK cell activity and concentration of asialo GM1 (ASGM1) positive splenocytes were measured in male C3H mice inoculated i.v. with CIRAS 3 tumor cells. Mice were housed individually or in groups of four and trained to run for eight weeks on a rodent treadmill; controls remained sedentary throughout the experimental period. At four weeks into the training protocol, mice were injected with the tumor cells and continued to run for four weeks after tumor exposure. There was a significant effect of physical activity (p less than 0.019) but not of housing on splenic NK cytotoxicity against tumor targets in vitro. When the data were analyzed by presence or absence of lung metastases, only those animals without visible lung tumors had significantly higher NK activity as a function of exercise relative to sedentary controls. There were no significant differences in the frequency of ASGM1+ splenocytes between trained and untrained animals, irrespective of presence or absence of lung tumor colonies. There was a significant effect of housing (p less than 0.02), but not of physical activity, in mice with successful tumor takes with greater numbers of group housed animals (29/59) with tumor relative to individually housed animals (13/60).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献