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831.
Gaspar R Chiappa Audrey Borghi-Silva Leonardo F Ferreira Claúdia Carrascosa Cristino Carneiro Oliveira Joyce Maia Ana Cristina Gimenes Fernando Queiroga Danilo Berton Eloara M V Ferreira Luis Eduardo Nery J Alberto Neder 《Journal of applied physiology》2008,104(5):1341-1350
Patients with chronic obstructive pulmonary disease (COPD) have slowed pulmonary O(2) uptake (Vo(2)(p)) kinetics during exercise, which may stem from inadequate muscle O(2) delivery. However, it is currently unknown how COPD impacts the dynamic relationship between systemic and microvascular O(2) delivery to uptake during exercise. We tested the hypothesis that, along with slowed Vo(2)(p) kinetics, COPD patients have faster dynamics of muscle deoxygenation, but slower kinetics of cardiac output (Qt) following the onset of heavy-intensity exercise. We measured Vo(2)(p), Qt (impedance cardiography), and muscle deoxygenation (near-infrared spectroscopy) during heavy-intensity exercise performed to the limit of tolerance by 10 patients with moderate-to-severe COPD and 11 age-matched sedentary controls. Variables were analyzed by standard nonlinear regression equations. Time to exercise intolerance was significantly (P < 0.05) lower in patients and related to the kinetics of Vo(2)(p) (r = -0.70; P < 0.05). Compared with controls, COPD patients displayed slower kinetics of Vo(2)(p) (42 +/- 13 vs. 73 +/- 24 s) and Qt (67 +/- 11 vs. 96 +/- 32 s), and faster overall kinetics of muscle deoxy-Hb (19.9 +/- 2.4 vs. 16.5 +/- 3.4 s). Consequently, the time constant ratio of O(2) uptake to mean response time of deoxy-Hb concentration was significantly greater in patients, suggesting a slower kinetics of microvascular O(2) delivery. In conclusion, our data show that patients with moderate-to-severe COPD have impaired central and peripheral cardiovascular adjustments following the onset of heavy-intensity exercise. These cardiocirculatory disturbances negatively impact the dynamic matching of O(2) delivery and utilization and may contribute to the slower Vo(2)(p) kinetics compared with age-matched controls. 相似文献
832.
Gerald J. Bargman Richard L. Neu Tadashi Kajii José Carneiro Leão Lytt I. Gardner 《Human genetics》1967,4(1):13-17
A female infant, first seen at age 7 months and again at 1 3/12 years, exhibited the following physical findings: low birth weight at full term; mental and growth retardation; brachycephaly; micrognathia; high arched palate; low set, slanted malformed pinnae; scant medial eyebrow hair; small, short nose with prominent skin folds over the nasal bridge; short neck; both hands were hypoplastic between thumb and index finger; a tendency to hold thumbs in pronation; abnormal dermatoglyphics; rocker-bottom feet; big toes kept in dorsi-flexed position; mottled skin; hypoplastic clitoris and labia minora.Cytogenetic studies on the patient revealed that 83% of the karyotyped peripheral leucocytes had 46 chromosomes and 17% had 47 chromosomes. Metaphases with 46 chromosomes exhibited the normal female complement. Metaphases with a count of 47 consistently had an extra chromosome in the C group. A labelled metaphase with 47 chromosomes showed only 1 late-replicating chromosome. The sex chromatin count was positive (30%) and no buccal cells with more than one sex chromatin body were observed.This study was supported in part by grants T1-AM-5277 and AM-02504 from the National Institutes of Health, United States Public Health Service.Postdoctoral trainee, National Institute of Arthritis and Metabolic Diseases. 相似文献
833.
V T Carneiro R A Caldas 《Comparative biochemistry and physiology. B, Comparative biochemistry》1983,75(1):61-64
Carboxylesterase activity corresponding to types A and B has been demonstrated in intact T. cruzi epimastigotes as shown by the hydrolysis of several esters of p-nitrophenol and the effect of suitable inhibitors. The in situ carboxylesterase activity was described by the Michaelis Menten kinetic approach. The apparent Vmax for the acetate and butyrate esters were 66.5 and 165.3 nmol hydrolysed per min and mg of protein respectively. An Arrhenius plot of the temperature dependent activity showed two sharp linear regions with a transition temperature of 31.6 degrees C. and energies of activation of 6.2 and 14.1 kcal/mol. The in situ carboxylesterase activity was inhibited 26% by paraoxon and 56% by N-ethylmaleimide, but not by p-chloromercuribenzoate. 相似文献
834.
Prof. Luiz de Siqueira Carneiro 《Mycopathologia》1968,36(3-4):365-366
835.
836.
837.
Robert L. Carneiro 《American anthropologist》1997,99(1):204-205
Foundations of Social Inequality. T. Douglas Price and Gary M. Feinman. eds. New York: Plenum Press, 1995. 290 pp. 相似文献
838.