196,084 research outputs found
Psycho-affettive reactions of social-sanitary professionals and paraprofessionals facing the death of geriatric patients La Habana, Cuba, 6-9 mayo 1992.
No full textRenin-Angiotensin-Aldosterone System Is Not Involved in the Arterial Stiffening Induced by Acute and Prolonged Exposure to High Altitude
No full textThis randomized, double-blind, placebo-controlled study was designed to explore the effects of exposure to very high altitude hypoxia on vascular wall properties and to clarify the role of renin-angiotensin-aldosterone system inhibition on these vascular changes. Forty-seven healthy subjects were included in this study: 22 randomized to telmisartan (age, 40.3±10.8 years; 7 women) and 25 to placebo (age, 39.3±9.8 years; 7 women). Tests were performed at sea level, pre- and post-treatment, during acute exposure to 3400 and 5400-m altitude (Mt. Everest Base Camp), and after 2 weeks, at 5400 m. The effects of hypobaric hypoxia on mechanical properties of large arteries were assessed by applanation tonometry, measuring carotid-femoral pulse wave velocity, analyzing arterial pulse waveforms, and evaluating subendocardial oxygen supply/demand index. No differences in hemodynamic changes during acute and prolonged exposure to 5400-m altitude were found between telmisartan and placebo groups. Aortic pulse wave velocity significantly increased with altitude (P<0.001) from 7.41±1.25 m/s at sea level to 7.70±1.13 m/s at 3400 m and to 8.52±1.59 m/s at arrival at 5400 m (P<0.0001), remaining elevated during prolonged exposure to this altitude (8.41±1.12 m/s; P<0.0001). Subendocardial oxygen supply/demand index significantly decreased with acute exposure to 3400 m: from 1.72±0.30 m/s at sea level to 1.41±0.27 m/s at 3400 m (P<0.001), remaining significantly although slightly less reduced after reaching 5400 m (1.52±0.33) and after prolonged exposure to this altitude (1.53±0.25; P<0.001). In conclusion, the acute exposure to hypobaric hypoxia induces aortic stiffening and reduction in subendocardial oxygen supply/demand index. Renin-angiotensin-aldosterone system does not seem to play any significant role in these hemodynamic changes. Clinical Trial Registration - URL: https://www.clinicaltrialsregister.eu/. Unique identifier: 2008-000540-14
Disappearance of isocapnic buffering period during increasing work rate exercise at high altitude
No full textBackground At sea level, ventilation kinetics are characterized during a ramp exercise by three progressively steeper slopes, the first from the beginning of exercise to anaerobic threshold, the second from anaerobic threshold to respiratory compensation point, and the third from respiratory compensation point to peak exercise. In the second ventilation phase, body CO2 stores are used to buffer acidosis owing to lactate production; it has been suggested that this extra CO2 production drives the ventilation increase. At high altitude, ventilation increases owing to hypoxia. We hypothesize that ventilation increase reduces body CO2 stores affecting ventilation kinetics during exercise. Design In eight healthy participants, we studied the ventilation kinetics during an exercise performed at sea level and at high altitude (4559 m). Methods We used 30 W/2 min step incremental protocol both at sea level and high altitude. Tests were done on a cycloergometer with breath-by-breath ventilation and inspiratory and expiratory gas measurements. We evaluated cardiopulmonary data at anaerobic threshold, respiratory compensation point, peak exercise and the VE/VCO2 slope. Results At high altitude: (a) peak Vo(2) decreased from 2595 +/- 705 to 1745 +/- 545mi/min (P < 0.001); (b) efficiency of ventilation decreased (VE/VCO2 slope from 25 +/- 2 to 38 +/- 4, P < 0.0001); (c) at each exercise step end-tidal pressure change for CO2 was lower; and (d) the isocapnic buffering period disappeared in seven over eight participants and was significantly shortened in the remaining participant. Conclusion Exercise performed at high altitude is characterized by two, instead of three, ventilation slopes
Correlazione tra profilo autonomico e fenotipo ecocardiografico in pazienti con cardiomiopatia ipertrofica.
No full textHigh-altitude hypoxia and periodic breathing during sleep: gender-related differences
No full textHigh-altitude exposure is characterized by the appearance of periodic breathing during sleep. Only limited evidence is available, however, on the presence of gender-related differences in this breathing pattern. In 37 healthy subjects, 23 male and 14 female, we performed nocturnal cardio-respiratory monitoring in the following conditions: (1) sea level; (2) first/second night at an altitude of 3400 m; (3) first/second night at an altitude of 5400 m and after a 10 day sojourn at 5400 m. At sea level, a normal breathing pattern was observed in all subjects throughout the night. At 3400 m the apnea-hypopnea index was 40.3 ± 33.0 in males (central apneas 77.6%, central hypopneas 22.4%) and 2.4 ± 2.8 in females (central apneas 58.2%, central hypopneas 41.8%; P < 0.01). During the first recording at 5400 m, the apnea-hypopnea index was 87.5 ± 35.7 in males (central apneas 60.0%, central hypopneas 40.0%) and 41.1 ± 44.0 in females (central apneas 73.2%, central hypopneas 26.8%; P < 0.01), again with a higher frequency of central events in males as seen at lower altitude. Similar results were observed after 10 days. With increasing altitude, there was also a progressive reduction in respiratory cycle length during central apneas in males (26.9 ± 3.4 s at 3400 m and 22.6 ± 3.7 s at 5400 m). Females, who displayed a significant number of central apneas only at the highest reached altitude, were characterized by longer cycle length than males at similar altitude (30.1 ± 5.8 s at 5400 m). In conclusion, at high altitude, nocturnal periodic breathing affects males more than females. Females started to present a significant number of central sleep apneas only at the highest reached altitude. After 10 days at 5400 m gender differences in the apnea-hypopnea index similar to those observed after acute exposure were still observed, accompanied by differences in respiratory cycle length
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dati fisiopatologici desunti da una ricerca longitudinale sul deterioramento cognitivo in soggetti in età senile
No full textDispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
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