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1.
  • 1.1. Coatis are chiefly diurnal, showing marked nycthemeral variations of body temperature and oxygen uptake.
  • 2.2. The thermoneutral zone extends from 25–33°C; the basal metabolic rate is about 40% below the value predicted from body mass.
  • 3.3. Thermoregulation in cold is excellent, partly due to decreasing thermal conductance at falling ambient temperatures.
  • 4.4. Exposure to temperatures above 35°C is endured for only short periods.
  • 5.5. Basal heart rate is reduced to about 70% of the predicted level. The contribution of heart rate to increased oxygen demands at falling ambient temperatures is rather low.
  • 6.6. The measured physiological characteristics of coatis are discussed with regard to the high mobility and the wide distribution range of these procyonids.
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2.
  • 1.1. The effects of temperature, salinity and declining O2 on the heart rates of nine species representing four animal phyla have been investigated in relation to other respiratory paramters.
  • 2.2. The effect of temperature on heart rate is at least the same as, and often greater than, the effect of temperature on O2 consumption, thus providing no evidence that adaptations of the cardiovascular system facilitate metabolic compensations for a temperature change.
  • 3.3. Responses to reduced acclimation salinity are very diverse among the various species, permitting no general conclusions about the role of the cardiovascular system in adaptations to estuarine habitats.
  • 4.4. At low PO2 the typical response is bradycardia, which is especially notable in species with a high capacity for anaerobic metabolism. Compensatory tachycardia, the expected response in vertebrates, is very rare in other animal groups.
  • 5.5. Estimates of cardiac output from these data generally agree with those obtained according to the Fick principle from blood gas tensions.
  • 6.6. The estimates of cardiac output are evaluated in terms of body size, temperature and the design of cardiac muscle, which is fundamentally different in various animal phyla.
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3.
  • 1.1. Heart rate-temperature relationships were determined on unanaesthetized, unrestrained eels acclimated to 15°C and 25°C.
  • 2.2. Heart rate in eels with intact vagal tonus exhibited a nearly complete temperature compensation. The degree of compensation was considerably reduced by blocking the vagus function with benzetimide.
  • 3.3. The difference in the sensitivity of heart rate to temperature change induced by temperature acclimation was significantly decreased after benzetimide-treatment.
  • 4.4. The inhibitory vagal tonus was significantly higher in warm-acclimated than in cold-acclimated eels.
  • 5.5. It is concluded that adaptation of heart rate to temperature is mediated by the parasympathetic system to a great extent.
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4.
  • 1.1. The effects of thermal acclimatization at 10 and 24°C on heart rate were investigated on unrestrained soles (Solea vulgaris).
  • 2.2. The sensitivity of heart rate to temperature changes induced by temperature acclimatization was higher in cold-acclimatized than in warm-acclimatized soles.
  • 3.3. Heart rate of cold-acclimatized fish to temperature changes was not affected by blocking the vagal tone with atropine.
  • 4.4. After atropine treatment the ability of heart rate to show thermal compensation decreased in warm-acclimatized soles.
  • 5.5. It is suggested that the vagus nerve can function differently at different temperatures.
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5.
  • 1.1. Some effects of restricting feed intake for 96 or 168 hr were determined in male Nubian goats.
  • 2.2. Goats restricted for 96 hr lost 11.6% of their body weight, and goats restricted for 168 hr lost 19.8%.
  • 3.3. Feed restriction for up to 168 hr did not produce significant effects on the heart rate, respiratory rate or rectal temperature.
  • 4.4. Haemoglobin concentration, packed cell volume and erythrocyte number were all decreased by feed restriction. There was also a tendency towards eosinopenia and lymphopenia.
  • 5.5. Feed restriction for 96 or 168 hr raised the plasma activity of aspartate transaminase, and did not affect significantly cholinesterase activity. Plasma amine oxidase activity was significantly reduced in goats restricted for 168 hr.
  • 6.6. Feed restriction produced significant increases in the blood or plasma concentrations of lactate. pyruvate, non-esterified fatty acids, cholesterol, ketone bodies and bilirubin.
  • 7.7. Significant decreases were found in the concentrations of total protein and calcium.
  • 8.8. No significant changes were observed in the plasma concentrations of glucose, sodium or potassium.
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6.
  • 1.1. Body temperature, oxygen consumption, CO2 production and muscle protein degradation rate were measured in the three quail lines selected for body size, a random bred line (RR) and two lines selected for large (LL) or small (SS) body size.
  • 2.2. The body temperature at 15 weeks of age was highest for small body size line and lowest for large body size line.
  • 3.3. The body temperature, oxygen consumption and CO2 production of females were significantly higher than that of males.
  • 4.4. The fractional degradation rate of muscle protein of SS, RR and LL lines were measured as 2.4, 1.6 and 1.2% per day in male, and 2.6, 1.7 and 1.4% per day in female.
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7.
  • 1.1. After step-like increases in salinity the shrimps exhibit the smallest increase in oxygen consumption in the lower salinity range. At higher salinities the shrimps show longer recovery times and greater increases in the metabolic rate after salinity shock.
  • 2.2. In steady-state experiments, the shrimps display the lowest oxygen consumption rates near the isosmotic point. The lowest metabolic rates occur at salinities of 3‰ and 10‰ At salinities of 20‰ and above the rate of metabolism increases by 20–30%.
  • 3.3. The calculated osmoregulatory work for animals in fresh water amounts to only 2.7% of routine metabolism and drops to 1.1% for shrimps in 3‰ and 0.7% in 5‰ salinity.
  • 4.4. Locomotory activity in the form of position change was not responsible for the increased oxygen consumption of the animals after salinity shocks. A “tentative swimming activity” by fast and frequent beating of the pleopods without position change may be an important factor in the increase of metabolic rates.
  • 5.5. In its temperature response, the brackish water population has a higher metabolic rate than the freshwater one. Between 5 and 35°C Q 10-values range from 4.01 to 1.37.
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8.
  • 1.1. The oxygen consumption of the marine teleost, Lichia amia was investigated under controlled laboratory conditions.
  • 2.2. The routine oxygen consumption showed a strong circadian rhythm with the fish being mainly active during the light period.
  • 3.3. The specific mass exponent (dimension: μg O2/g/hr) is temperature independent and ranges from 0.27–0.29.
  • 4.4. Starving the fish results in a mean decrease in active, routine and standard oxygen consumption of 21%, 24% and 20%, respectively.
  • 5.5. Feecling led to an increase in the oxygen consumption of the teleosts, with the mean metabolic rate over the 24 hr that followed, being 58% and 50% higher for fish that had been starved for 162hr and 40 hr, respectively.
  • 6.6. Apparent SDA showed some variation and ranged from 6.0 to 35.5%.
  • 7.7. The results obtained are generally in agreement with those recorded for other teleosts.
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9.
  • 1.1. Measurements of the rate of nitrogen consumption, total nitrogen and ammonia excretion and nitrogen absorption of bream, Abramis brama L. (body weight range 0.4–519 g wet wt) were made at 10, 15 and 20 C.
  • 2.2. Fish were fed once daily on live zooplankton collected in Lake Balaton and cultured Tubifex sp. at 5–15% of their body weight.
  • 3.3. Fish size and temperature had a combined effect on the rate of total nitrogen excretion. Total nitrogen excretion did not increase proportionally with an increase in consumption.
  • 4.4. On average, 52–80% of the nitrogen consumed with food was excreted by bream.
  • 5.5. The greatest part of total nitrogen excretion was ammonia and its proportion in the total ranged between 53 and 75%.
  • 6.6. Temperature did not have any significant effect on the proportion of excreted ammonia and the rate of excreted total nitrogen was the only factor determining its proportion in the total.
  • 7.7. The rate of nitrogen absorption of bream was surprisingly very high.
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10.
  • 1.1. Heart rates of five unrestrained white-tailed deer fawns were monitored for 24 hr periods at intervals between birth and weaning at about 100 day of age (25 kg body weight).
  • 2.2. Mean heart rates during lying-resting activity declined exponentially with body weight to about 54% of the neonatal rate.
  • 3.3. Increases in the mean heart rate with spontaneous changes in activity from lying to lying-ruminating, standing, foraging, walking and running were related curvilinearly to body weight.
  • 4.4. Heart rates for these same activities were higher when fawns were alarmed or excited.
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11.
  • 1.1. An exact, explicit quartic solution to the energy budget can be used to calculate the operative temperature, the surface temperature of a wet organism, and the metabolic rate.
  • 2.2. All of the approximations and iteration methods arrive at solutions close to the proper root and do not converge around the other three physically unrealistic roots.
  • 3.3. A second-order Taylor approximation is satisfactory, but the first-order Taylor approximation is not.
  • 4.4. A new simple 4th order polynomial is introduced to estimate the saturated vapor pressure function.
  • 5.5. Partial differential analysis is used to show the errors associated with the use of mounts and mount analogs.
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12.
  • 1.1. The exponent (b) relating metabolic rate to dry weight in excised gills of Tagelus plebeius is not maintained constant throughout the seasons or upon acute exposure to temperatures of 9–34°C.
  • 2.2. Acclimation (11–29°C) and test (9–34°C) temperatures have a significant effect (α = 0.01) on the mean rate of oxygen uptake by the gills.
  • 3.3. Positive seasonal thermal acclimation is observed up to acclimation temperatures of 19.5–20°C, which is also the temperature of minimum respiratory response to all acute test temperatures.
  • 4.4. Regions of thermal metabolic insensitivity are seen over small acute temperature ranges near the acclimation temperatures.
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13.
  • 1.1. Both juveniles and adults of this rare salamander were studied.
  • 2.2. The rate of evaporative water loss increased with temperature and at lower humidities.
  • 3.3. At all four temperatures and three humidities studied, adults lost water at a lower rate than juveniles.
  • 4.4. Aggregating juveniles reduced water loss especially at lower moisture.
  • 5.5. The rate of water uptake was greater in juveniles than in adults.
  • 6.6. Juveniles were capable of absorbing moisture from moist soil even at 40% saturated soil.
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14.
  • 1.1. The oxygen uptake rate of avian adipose tissue, liver and skeletal muscle slices were measured.
  • 2.2. The energy consumption of fat was less than one tenth that of liver and muscle.
  • 3.3. Thus, interspecific allometric equations for the prediction of basal metabolic rate from body mass will not be accurate throughout the avian annual cycle unless changes in body composition are taken into account.
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15.
  • 1.1. The role of the visceral nerve in mediating the changes in heart rate associated with different behavioral patterns was investigated in Megalobulimus sanctipauli.
  • 2.2. The results of acute and chronic denervation experiments indicate that the visceral nerve has no excitatory or inhibitory tonic action on the heart of snails retracted into the shell, nor does it account for the increase in heart rate associated with the locomotion and feeding behaviors.
  • 3.3. These changes in heart rate are, probably, indirect effects of increased activity such as an increase in venous return.
  • 4.4. The visceral nerve is responsible for approximately 3/4 of the increase in heart rate associated with the first minute of extrusion.
  • 5.5. The small increase in heart rate observed in denervated animals is probably caused by an increase in venous return generated by muscle activity that forces the head and food out of the shell.
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16.
  • 1.1. The role ofinterleukin-1 (IL-1) in sepsis-induced muscle proteolysis was assessed by treating septic rats with recombinant IL-1 receptor antagonist (rIL-Ira).
  • 2.2. In initial experiments, we tested the effectiveness of IL-Ira in preventing muscle proteolysis induced by administration of IL-1.
  • 3.3. When normal rats were treated with rIL-α (three intraperitoneal doses of 100 μ g/kg body weight each over 16 hr), total and myofibrillar muscle protein breakdown rates, measured as release oftyrosine and 3-methylhistidine, respectively, by incubated extensor digitorum longus muscles, were significantly increased.
  • 4.4. This metabolic response to IL-α was completely abolished by rIL-Ira, administered as three intraperitoneal doses of 3 mg/kg body weight each over 16hr.
  • 5.5. In subsequent experiments, sepsis was induced in rats by cecal ligation and puncture (CLP); non-septic rats were sham-operated.
  • 6.6. Treatment of septic rats over 16hr with a total dose of 25mg/kg body weight of rIL-Ira reduced, but did not normalize, the increased muscle protein breakdown rates seen during sepsis.
  • 7.7. When the dose of rIL-Ira was more than doubled and given as a constant infusion at a rate of 4.2 mg/kg body weight/hr for 16 hr, the increased rate of muscle proteolysis in septic rats was normalized.
  • 8.8. The present study offers the first direct evidence that IL-1 is involved in the regulation of muscle proteolysis during sepsis.
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17.
  • 1.1. Glucose entry rate was measured in two camels (Camelus dromedarius) and two sheep (Ovis wies) in the fed state and also after 72 hr of fasting.
  • 2.2. Plasma glucose concentration in the fed camels (129 mg/100 ml) was considerably higher than that of the fed sheep (63 mg/100 ml).
  • 3.3. The mean glucose entry rate in the fed camels (1.67mg/min per kg body wt) was very similar to the sheep (1.79 mg/min per kg body wt).
  • 4.4. When the results were expressed as a function of the metabolic body size, the entry rates in the camel were 1.5 times greater than that of the sheep.
  • 5.5. The relationship between glucose entry rate and plasma glucose concentration in different mammalian species is discussed.
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18.
  • 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
  • 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
  • 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
  • 4.4. The food type also seems to exert an important effect on oxygen consumption.
  • 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
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19.
  • 1.1. Kidneys of Lophius were perfused from the renal portal vein with a Ringer's solution.
  • 2.2. Mammalian and piscine neurohypophysial hormones (in doses of 20–500 ng/kg body wt) did not affect the rate of urine production or the urinary concentration of inorganic ions.
  • 3.3. The rate of urine production and the urinary concentration of magnesium and sodium ions varied with the concentration of magnesium in the perfusate.
  • 4.4. The rate of urine production was positively correlated with urine magnesium concentration (r = 0.83 ± 0.04) and negatively correlated with that of sodium (r = −0.40).
  • 5.5. The urinary concentration of sodium ions varied inversely with that of magnesium ions (r = −0.89).
  • 6.6. Ouabain treatment (0.1–0.8 mM/l) reduced the rate of urine production by over 60% and altered, to varying extents, the pattern of electrolyte excretion. A simple model for the mode of formation of urine by the aglomerular kidney, based on the present results and other observations is suggested.
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20.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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