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D Van Nimmen J Weyne G Demeester I Leusen 《Journal of cerebral blood flow and metabolism》1986,6(5):584-589
The effect of ventriculocisternal perfusion with mock CSF with alkaline or acidic pH on the local CMRglu (LCMRglu) in the caudatoputamen was studied in artificially ventilated and relaxed rats. In control rats both lateral cerebral ventricles were perfused with mock CSF at pH 7.4. In the experimental series one cerebral ventricle was infused with normal mock CSF while the other was infused with mock CSF in which the pH was decreased or increased by changing [HCO-3]. LCMRglu was depressed in acidotic brain tissue while it was strongly increased in alkalotic brain tissue. The importance of these alterations in brain glucose metabolism for the homeostatic regulation of brain pH is discussed. 相似文献
83.
A comparison of pulmonary, cardiovascular and metabolic responses was made in 32 subjects consisting of 11 able-bodied, 8 paraplegics (T4-L3 lesions) and 13 quadriplegics (C5-C8 lesions) during maximal arm cranking exercise. A progressive continuous arm cranking test, modified for each group, was employed to elicit maximal responses with pulmonary and metabolic determinations made with open circuit spirometry and selected cardiovascular measurements made by impedance cardiography. Additionally, non-exercise static and dynamic lung function assessments were made. Quadriplegics had significantly lower (p less than 0.05) tidal volumes, vital capacities, forced expiratory volumes at 1 seconds, and maximal breathing capacities than the other two groups. The mean peak VO2 during maximal arm cranking was 28.2, 25.3 and 12.0 ml/kg.min for the able-bodied (AB), paraplegics (PP) and quadriplegics (QP), respectively. Furthermore, reduced cardiovascular function was observed in the QP as evident in the low peak HR (109 b/min), peak SV (52 ml/b) and peak Q (5.7 l/min). Values for the QP were 64% and 64% peak HR, 89% and 50% peak SV and 54% and 33% peak Q of values observed for the PP and AB groups, respectively. The peak SV and Q values were significantly lower (P less than 0.05) for the PP group when compared with the AB group. Although not statistically significant the estimated a-v O2 difference was higher for both spinal cord injured groups (14.0 and 14.6 ml O2/100 ml, PP and QP respectively). The impaired work capacity and reduced oxygen transport and utilisation of the QP group can be attributed to impaired sympathetic cardiac stimulation and a smaller available active muscle mass. 相似文献
84.
由于新药toreetrapib的临床研究未获预期结果 ,以及残存心血管危险性这一概念的提出,近年人们再次对高密度脂蛋白(HDL)及高密度脂蛋白-胆固醇(HDL-C)给予高度关注.研究提示,在关注HDL-C水平的同时,不能忽视HDL的功能状态.目前最有效和安全的升高HDL-C水平的方法 还是生活方式调节,主要包括锻炼、减轻体重和戒烟等. 相似文献
85.
Elizabeth B Haagsma Ingrid I Van Gameren Johan Bijzet Marcel D Posthumus Bouke P C Hazenberg 《Amyloid》2007,14(3):221-226
To estimate the evolution of amyloid in tissue, we studied abdominal fat aspirates of cases with familial amyloidotic polyneuropathy (FAP) longitudinally at regular intervals between 1994 and 2006. In 22 cases (13 carriers and nine patients) not yet transplanted median follow-up was 3.3 years (range 0.4-11.3). We found a significant increase in the amyloid grade of fat tissue from 2+ to 4+ and from 0 to 4+ in two of three subjects with follow-ups of >7 years, after 7 and 11 years, respectively. All other subjects remained negative or did not show a significant change. In 11 liver transplant patients, follow-up with fat aspirate was available with a median duration of 3.1 years (range 1.0-10.1). A comparison was made with cardiac amyloid as judged by the cardiac septum diameter and the serum NT-ProBNP (N-terminal pro-B-type natriuretic peptide) level. No stable increase of amyloid in fat was seen in any patient. A stable decrease of amyloid grade was seen in one patient 5 years after transplantation. In contrast, the cardiac septum diameter increased >or=4 mm in six of the 11 transplant patients. Our study shows the diagnostic utility of a regularly repeated fat aspirate in carriers at risk for the development of ATTR amyloidosis. Evolution of amyloid deposition in fat tissue is very gradual. After liver transplantation, amyloid deposition in fat tissue seems to stabilize and may even decrease in the long term, whereas amyloid deposition in cardiac tissue appears to be progressive. 相似文献
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Edited by Lauren Dundes. Walnut Creek (CA): Altamira Press, 2003. 239 pages. $27.95, paperback, $75.00, hardback. 相似文献
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