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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

The oxygen cost of cycling in patients with chronic obstructive pulmonary disease and the effect of increasing ventilatory requirements /

Gravel, Geneviève January 2005 (has links)
The objective of this study was to assess the oxygen cost of various intensities of steady-state cycling. VO2 (ml·min -1·kg-1) was measured at rest, during unloaded cycling (UL), 20 Watts, 50% (SS50) & 65% (SS65) of peak watts in 40 COPD patients (64 +/- 9 yrs; FEV1/FVC: 48 +/- 17 % predicted; FEV1:36 +/- 14 % predicted) and 28 age-matched healthy controls (CTRL). Despite higher VE (L·min -1) in COPD vs. CTRL (UL: 20.6 +/- 3.4 vs. 15.4 +/- 4.1; 20W: 24.3 +/- 4.5 vs. 17.8 +/- 4.2), VO2 at rest, at UL and 20W was not higher in COPD compared to CTRL. In addition, comparable slope and intercept coefficients for the VO2 vs. Watt relationship were obtained in COPD and CTRL for submaximal cycling of low to moderate intensity. (Abstract shortened by UMI.)
52

The effects of ß-blockers on exercise parameters in heart failure /

Bridges, Eileen Joan January 2002 (has links)
Purpose. To examine the outcome of a 6-month treatment with carvedilol or metoprolol on peak and submaximal exercise performance and ventilatory efficiency in patients with heart failure (HF). / Methods. 27 patients with HF were randomized to receive either metoprolol or carvedilol for 6 months and compared with 12 healthy controls. Maximal exercise capacity was assessed at baseline and after 6 months with a symptom limited incremental treadmill protocol (RAMP). Submaximal exercise was determined to be the portion of exercise below a respiratory exchange ratio of 1.0. Peak heart rate (HR), oxygen uptake (VO2), and ventilatory equivalent for O2 and CO2 were recorded. The slopes of the VE vs. VCO2, VE vs. VO2 and VE/VCO2 vs. VO2 relationships were calculated for each subject from submaximal values. / Results. Resting HR decreased to similar extent in both treatment groups. There were no other significant changes in resting hemodynamics or ventricular function. Peak VO2 and HR decreased significantly in both treatment groups. Peak VE/VCO2 and submaximal VCO 2 vs. VE slope were not changed significantly after therapy. / Conclusion. beta-blocker treatment with either metoprolol or carvedilol does not decrease the slope of the VCO2 vs. VE relationship. The present observations may suggest that the exaggerated ventilatory response of patients with moderate HF is not mediated by beta-adrenergic receptors.
53

Effects of NaCl on growth and physiology of Pinus leiophylla seedlings

Jimenez-Casas, Marcos 11 1900 (has links)
Identification of salt- resistant tree species and genotypes is needed for rehabilitation of lands affected by salinity in Mexico. This dissertation consists of four studies for analyzing the responses of Pinus leiophylla seedlings to salt. In the first study, resistance to salt stress was studied in six-month-old seedlings from eight different sources of seed collected from the areas with contrasting precipitation levels. Plants from the xeric areas were shorter and had smaller stem diameters but were less sensitive to salt stress and recovered faster from salt injury compared with the plants from mesic sites, suggesting that morphological and physiological adaptations to drought were helpful with salt stress resistance. In the second study, fascicle needle production and tissue ion accumulation were examined in NaCl-treated three-month-old seedlings from two populations of the xeric origin and two populations from the mesic areas. Seedlings from the xeric population of San Felipe developed fewer fascicles and had shorter needles compared with seedlings from the remaining three populations. NaCl treatment delayed the emergence of fascicles and reduced the fascicle needle production and needle length. However, the extent of needle injury and ion accumulation in shoots were lower in the San Felipe seedlings compared with the other studied populations. In the third study, the effects of branch pruning and seedling size on total transpiration and accumulation of Na+ and Cl- in tissues were examined. Total plant transpiration, as affected by plant size and branch pruning, was correlated with Na+ and Cl- needle concentrations and needle necrosis. Branch pruning reduced ion accumulation in the shoots and needle necrosis levels in short seedlings but not in the tall seedlings. In the fourth study, sprouting and physiological responses of 16 month-old-seedling to salt were examined. NaCl treatment concentrations of 100, 150, and 200 mM reduced gas exchange and root hydraulic conductance, caused needle injury and triggered sprouting of adventitious shoots. Sprouting from the upper parts of the main stem and lateral branches was three times greater with 100 and 150 mM NaCl compared with 200 mM NaCl treatment but, at the base of the stem, sprout numbers were similar for all NaCl treatments.
54

An apparatus for determining the CO_2 gas-exchange of a forest tree in the field

HAGIHARA, Akio, 萩原, 秋男, HOZUMI, Kazuo, 穂積, 和夫, HANDA, Shigeru, 半田, 繁 03 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
55

Synchronized delivery of inspired nitric oxide : effects on oxygenation and pulmonary tension during artificial ventilation /

Heinonen, Erkki. January 2002 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 4 uppsatser.
56

Respiratory drive assessment : an evaluation of the breath-by-breath occlusion pressure method in man /

Hellström, Lars Gösta, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 7 uppsatser.
57

Physiological responses to exercise in standardbred trotters with special reference to total blood volume /

Funkquist, Pia, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Bilagan utgöres av sammanfattnig på svenska med titeln: Fysiologiskt svar på arbete hos varmblodiga travhästar i relation till total blodvolym. Härtill 5 uppsatser.
58

Effect of body posture on regional ventilation and perfusion at normal and increased gravity /

Petersson, Johan, January 2006 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 5 uppsatser.
59

Leaf phenology, fecundity, and biomass allocation of the invasive shrub Lonicera maackii (Rupr.) maxim in contrasting light environments /

Lieurance, Deah M. January 2004 (has links)
Thesis (M.S.)--Ohio University, November, 2004. / Includes bibliographical references (p. 48-49)
60

Predicting survival probability for major congestive heart failure events in patients attaining a low peak respiratory exchange ratio during cardiopulmonary exercise testing

Kenjale, Aarti. January 1900 (has links)
Thesis (M.S.)--The University of North Carolina at Greensboro, 2008. / Directed by Paul Davis; submitted to the Dept. of Kinesiology. Title from PDF t.p. (viewed Jul. 20, 2010). Includes bibliographical references (p. 104-112).

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