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11.
Patrick J. Taylor 《Canadian Medical Association journal》1991,145(10):1362-1363
12.
M. D. Taylor M. L. de Ceballos S. Rose P. N. Chong P. Jenner C. D. Marsden 《Journal of neural transmission (Vienna, Austria : 1996)》1991,3(2):99-108
Summary Aged common marmosets were treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP; 0.5–2.0 mg/kg/week i.p.) for 16 or 24 weeks, observed for a total of 30 weeks and then killed for measurement of biochemical pramaters in basal ganglia. The MPTP treatment induced a marked depletion in dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid levels in the caudate nucleus and putamen. In contrast, the concentrations of five neuropeptides: [Met5]-enkephalin, [Leu5]-enkephalin, cholecystokinin, substance P and neurotensin as measured by a combined HPLC/RIA method, remained unaltered in all basal ganglia regions examined. Enkephalin precursor levels, as reflected by cryptic [Met5]-enkephalin content, were increased in the putamen, but not in the caudate nucleus, as a consequence of MPTP administration. Cryptic [Leu5]-enkephalin content remained unchanged in the striatum of MPTP treated marmosets. Overall, these results suggest an increase in striatal [Met5]-enkephalin release following chronic MPTP treatment of aged marmosets. However, the chronic treatment of aged marmosets with MPTP does not reproduce the neuropeptide alterations characteristic of Parkinson's disease. 相似文献
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Increased production of peroxidation products associated with cardiac operations. Evidence for free radical generation 总被引:7,自引:0,他引:7
D Royston J S Fleming J B Desai S Westaby K M Taylor 《The Journal of thoracic and cardiovascular surgery》1986,91(5):759-766
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved. 相似文献
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PRIMARY LYMPHOSARCOMA OF THE STOMACH 总被引:3,自引:3,他引:0
Taylor ES 《Annals of surgery》1939,110(2):200-221
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Introduction
Although ependymoma is the third most common pediatric brain tumor, we know little about the genetic/epigenetic basis of its initiation, maintenance, or progression. This is due in part to the heterogeneity of the disease, as well as the small sample size of the cohorts analyzed in most studies. 相似文献18.
NTS fallout-induced multiple myeloma in Utah. 总被引:1,自引:0,他引:1
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Predicting failure in polytetrafluoroethylene vascular access grafts for hemodialysis: a pilot study
C R Shackleton D C Taylor A R Buckley V A Rowley P L Cooperberg P D Fry 《Canadian journal of surgery》1987,30(6):442-444
In order to determine if serial, noninvasive evaluation of polytetrafluoroethylene (PTFE) vascular access grafts could identify a subgroup of patients at risk for thrombosis, the authors studied flow characteristics, using duplex ultrasonic scanning, in 18 hemodialysis patients with forearm loop grafts. On average, five examinations were performed per patient over the 10-month study period. Seven episodes of thrombosis occurred in six patients. The mean Doppler flow in grafts that subsequently thrombosed was significantly lower than in those that did not (544 +/- 218 ml/min versus 843 +/- 391 ml/min, p less than 0.001). The interval from last examination to thrombosis ranged from 13 to 58 days. At a defined cut-off flow of 450 ml/min, this test yielded a sensitivity of 83% and a specificity of 75% for episodes of thrombosis occurring within 2 to 6 weeks. The authors conclude that episodes of thrombosis in PTFE arm loop grafts are usually preceded by significantly lower Doppler-measured flow than grafts that do not thrombose and that it may be possible, by this means, to identify grafts at risk. 相似文献
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