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J H Coote B M Stone G Tsang 《European journal of applied physiology and occupational physiology》1992,64(2):178-181
The structure of sleep in lowland visitors to altitudes greater than 4000 m is grossly disturbed. There are no data on sleep in long-term residents of high altitudes. This paper describes an electroencephalographic study of sleep in high altitude dwellers who were born in and are permanent residents of Cerro de Pasco in the Peruvian Andes, situated at 4330 m. Eight healthy male volunteers aged between 18 and 69 years were studied. Sleep was measured on three consecutive nights for each subject. Electroencephalographs, submental electromyographs and electro-oculograms were recorded. Only data from the third night were used in the analysis. The sleep patterns of these subjects resembled the normal sleep patterns described by others in lowlanders at sea level. There were significant amounts of slow wave sleep in the younger subjects and rapid eye movement sleep seemed unimpaired. 相似文献
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T Velásquez 《American journal of physical anthropology》1970,32(2):251-263
Altitude adaptation was measured at sea level and high altitudes in sea level adapted and high altitude adapted natives. Tests of work capacity as measured by O2 consumption, pulse rate, and ventilation rate are reported. It is noted that comparing our results with those of other investigators is difficult due to variations in terminology and procedure. This suggests the necessity of more precise definitions in studies of the physical activity of high altitude natives. 相似文献
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Some of the blood and urinary constituents, oral glucose tolerance and urea clearance were determined in lowlanders at sea level (200 m) and at an altitude of 4, 000 m after their stay of two years. These data were compared with those of natives of high altitude area. The concentration of proteins, cholesterol, creatinephosphokinase and aspartate aminotransferase in blood among lowlanders after 2 year acclimatization were similar to that observed among highlanders. The urinary excretion of creatine and creatinine was of similar magnitude in highlanders and in acclimatized lowlanders but that of 17-keto and 17-hydroxysteroids was higher among highlanders. High altitude acclimatization among lowlanders facilitated appearance of a sharp peak in oral glucose tolerance curves and a decreased fasting blood glucose values. It also induced a restriction in renal filtration as indicated by a depressed urea clearance among lowlanders. 相似文献
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Unusually low hemoglobin levels were found in a healthy population of Tibetan speaking people residing at 3800 m along the Nepal-Tibet frontier in northwest Nepal. Peoples native to the Tibetan plateau may have evolved novel adaptive strategies to hypoxic stress. 相似文献
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Maria Rivera-Ch Alfredo Gamboa Fabiola Léon-Velarde Jose-Antonio Palacios David F O'Connor Peter A Robbins 《Journal of applied physiology》2003,94(3):1263-8; discussion 1253-4
Sea-level (SL) natives acclimatizing to high altitude (HA) increase their acute ventilatory response to hypoxia (AHVR), but HA natives have values for AHVR below those for SL natives at SL (blunting). HA natives who live at SL retain some blunting of AHVR and have more marked blunting to sustained (20-min) hypoxia. This study addressed the question of what happens when HA natives resident at SL return to HA: do they acclimatize like SL natives or revert to the characteristics of HA natives? Fifteen HA natives resident at SL were studied, together with 15 SL natives as controls. Air-breathing end-tidal Pco(2) and AHVR were determined at SL. Subjects were then transported to 4,300 m, where these measurements were repeated on each of the following 5 days. There were no significant differences in the magnitude or time course of the changes in end-tidal Pco(2) and AHVR between the two groups. We conclude that HA natives normally resident at SL undergo ventilatory acclimatization to HA in the same manner as SL natives. 相似文献
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Cynthia M. Beall Kingman P. Strohl John Blangero Sarah Williams-Blangero Laura A. Almasy Michael J. Decker Carol M. Worthman Melvyn C. Goldstein Enrique Vargas Mercedes Villena Rudy Soria Ana Maria Alarcon Cristina Gonzales 《American journal of physical anthropology》1997,104(4):427-447
Newcomers acclimatizing to high altitude and adult male Tibetan high altitude natives have increased ventilation relative to sea level natives at sea level. However, Andean and Rocky Mountain high altitude natives have an intermediate level of ventilation lower than that of newcomers and Tibetan high altitude natives although generally higher than that of sea level natives at sea level. Because the reason for the relative hypoventilation of some high altitude native populations was unknown, a study was designed to describe ventilation from adolescence through old age in samples of Tibetan and Andean high altitude natives and to estimate the relative genetic and environmental influences. This paper compares resting ventilation and hypoxic ventilatory response (HVR) of 320 Tibetans 9–82 years of age and 542 Bolivian Aymara 13–94 years of age, native residents at 3,800–4,065 m. Tibetan resting ventilation was roughly 1.5 times higher and Tibetan HVR was roughly double that of Aymara. Greater duration of hypoxia (older age) was not an important source of variation in resting ventilation or HVR in either sample. That is, contrary to previous studies, neither sample acquired hypoventilation in the age ranges under study. Within populations, greater severity of hypoxia (lower percent of oxygen saturation of arterial hemoglobin) was associated with slightly higher resting ventilation among Tibetans and lower resting ventilation and HVR among Aymara women, although the associations accounted for just 2–7% of the variation. Between populations, the Tibetan sample was more hypoxic and had higher resting ventilation and HVR. Other systematic environmental contrasts did not appear to elevate Tibetan or depress Aymara ventilation. There was more intrapopulation genetic variation in these traits in the Tibetan than the Aymara sample. Thirty-five percent of the Tibetan, but none of the Aymara, resting ventilation variance was due to genetic differences among individuals. Thirty-one percent of the Tibetan HVR, but just 21% of the Aymara, HVR variance was due to genetic differences among individuals. Thus there is greater potential for evolutionary change in these traits in the Tibetans. Presently, there are two different ventilation phenotypes among high altitude natives as compared with sea level populations at sea level: lifelong sustained high resting ventilation and a moderate HVR among Tibetans in contrast with a slightly elevated resting ventilation and a low HVR among Aymara. Am J Phys Anthropol 104:427–447, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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Kayser Bengt; Favier Roland; Ferretti Guido; Desplanches Dominique; Spielvogel Hilde; Koubi Harry; Sempore Brigitte; Hoppeler Hans 《Journal of applied physiology》1996,81(6):2488-2494
Kayser, Bengt, Roland Favier, Guido Ferretti, DominiqueDesplanches, Hilde Spielvogel, Harry Koubi, Brigitte Sempore, and HansHoppeler. Lactate and epinephrine during exercise in altitudenatives. J. Appl. Physiol. 81(6):2488-2494, 1996.We tested the hypothesis that the reported lowblood lactate accumulation ([La]) during exercise inaltitude-native humans is refractory to hypoxia-normoxia transitions byinvestigating whether acute changes in inspiredO2 fraction(FIO2) affect the[La] vs. power output ()relationship or, alternatively, as reported for lowlanders, whetherchanges in [La] vs. on changes inFIO2 are related tochanges in blood epinephrine concentration ([Epi]). Altitude natives [n = 8, age 24 ± 1 (SE) yr, body mass 62 ± 3 kg, height 167 ± 2 cm]in La Paz, Bolivia (3,600 m) performed incremental exercise with twolegs and one leg in chronic hypoxia and acute normoxia (AN). Submaximalone- and two-leg O2 uptake (O2) vs. relationships were not altered byFIO2. AN increased two-legpeak O2 by 10% and peak by 7%. AN paradoxically decreasedone-leg peak O2 by 7%,whereas peak remained the same. The[La] vs. relationships were similar tothose reported in unacclimatized lowlanders. There was a shift to theright on AN, and maximum [La] was reduced by 7 and 8% forone- and two-leg exercises, respectively. [Epi] and[La] were tightly related (mean r = 0.81) independently ofFIO2. Thus normoxiaattenuated the increment in both [La] and [Epi]as a function of , whereas the correlation between[La] and [Epi] was unaffected. These data suggest loose linkage of glycolysis to oxidative phosphorylation under influence from [Epi]. In conclusion, high-altitudenatives appear to be not fundamentally different from lowlanders with regard to the effect of acute changes inFIO2 on [La] during exercise. 相似文献
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Red blood cell carbonic anhydrase (CA) activity has not been studied in high altitude natives. Because CA is an intraerythocytic enzyme and high altitude natives are polycythemic, it is important to know if the activity of CA per red cell volume is different from that of their sea level counterparts. Blood was collected from healthy subjects living in Lima (150m) and from twelve subjects from Cerro de Pasco (4330m), and hematocrit and carbonic anhydrase activity were measured. As expected, the high altitude natives had significantly higher hematocrits than the sea level controls (p = 0.0002). No difference in the CA activity per milliliter of red cells was found between the two populations. There was no correlation between the hematocrit and CA activity. 相似文献
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S. C. Jain Jaya Bardhan Y. V. Swamy A. Grover H. S. Nayar 《International journal of biometeorology》1981,25(1):47-52
Body fluid compartments were studied in a group of high altitude natives after a stay of two months at sea level and during 12 days at an altitude of 3,500 m. Measurements of total body water and extracellular water were made on day 3 and 12 of reinduction to altitude, while plasma volume was measured on day 12 only. The intracellular water, blood volume and red cell mass were computed from the above parameters. Total body water and intracellular water decreased by 3.3% (P<0.001) and 5.0% (P<0.001) respectively by the 3rd day at altitude and did not change thereafter. Extracellular water increased progressively at altitude, but the increase was not significant. Blood volume and red cell mass increased significantly while plasma volume decreased at altitude. These data were compared with that of low landers. This study suggested body hypohydration on high altitude induction in low landers as well as in high altitude natives on reinduction. 相似文献
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F L Velarde D Espinoza C Monge C de Muizon 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1991,313(9):401-406
A population of chicken (Gallus gallus) from the Peruvian Andes (4,000 m) carrying a high hemoglobin-oxygen affinity has been identified. This property remained stable after over 1 year residence at sea level and was transmitted to the descendants born at sea level. Chicken were introduced in South America during the Spanish conquest and therefore their adaptation time to high altitude is less than 500 years. This finding shows that a genotypic change in hemoglobin function can occur in an extremely short evolutionary time and leads to some reflections on the high altitude adaptation of the mammals that migrated to South America during the great Plio-Pleistocene interchange. 相似文献
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