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Results for “physiologic variables”

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At least 109 records · Page 6Linked to original sources
PubMed1989

Effect of chronic caloric restriction on physiological variables related to energy metabolism in the male Fischer 344 rat.

In the present study, a number of physiological and behavioral measures that are related to metabolism were continuously monitored in 19-month-old male Fischer 344 rats that were fed ad libitum or fed a caloric restricted diet. Caloric restricted rats ate fewer meals but consumed more food during each meal and spent more time eating per meal than did rats fed ad libitum. Therefore, the timing and duration of meals as well as the total number of calories consumed may be associated with life extension. Average body temperature per day was significantly lower in restricted rats but body temperature range per day and motor activity were higher in restricted rats. Dramatic changes in respiratory quotient, indicating rapid changes in metabolic pathway and lower temperature, occurred in caloric restricted rats when carbohydrate reserves were depleted. Lower body temperature and metabolism during this time interval may result in less DNA damage, thereby increasing the survival potential of restricted rats. Nighttime feeding was found to synchronize physiological performance between ad libitum and caloric restricted rats better than daytime feeding, thereby allowing investigators to distinguish the effects of caloric restriction from those related solely to the time-of-day of feeding.

Animals↗
PubMed1999

[Mechanisms controlling blood pressure and heart rate variability: physiological and physiopathological aspects].

These studies explore the mechanisms controlling the 24-hour, the ultradian and the instantaneous variability in blood pressure and RR interval in humans. Several studies are undertaken to determine the contribution of environment, genetics, sleep-wake cycle and specific sleep stages on the blood pressure and RR interval variability in normal subjects. The analysis of the effects of cardiac failure, of renal failure and of organ transplantation provides further information on the mechanisms controlling blood pressure and RR interval variability in pathological conditions.

Blood Pressure↗
PubMed1993

Effect of furosemide on physiologic variables in exercising horses.

Twelve horses (6 Standardbreds and 6 Thoroughbreds) received IM injections of furosemide (250 mg) or physiologic saline solution and performed standard exercise tests, to assess the effects of furosemide and breed on blood gas values, PCV, plasma lactate concentration, and heart rate during exercise. After furosemide administration, arterial and venous blood pH values were significantly (P < 0.05) increased. Partial pressures of O2 and CO2 in arterial blood and of CO2 in venous blood (PaO2, PaCO2, and PVCO2, respectively) were unaffected by furosemide treatment, whereas venous partial pressures of O2 (PVO2) were significantly (P < 0.05) less during exercise after furosemide treatment, suggesting an increase in oxygen uptake by the exercising muscles or a change in cardiac output. A significant (P < 0.05) difference was found between Thoroughbred and Standardbred values for arterial and venous pH, PaO2, PaCO2, plasma lactate concentration, and heart rate, suggesting that Standardbreds exercised at a relatively higher work rate than did Thoroughbreds.

Animals↗
PubMed1993

Physiologic variables and fluid resuscitation in the postoperative intensive care unit patient.

OBJECTIVE: To examine how critical surgical illness and its management alter some of the biochemical, physiologic, and hematologic parameters commonly used to monitor postoperative, critically ill patients. DESIGN: Prospective survey of 150 patients over 3 months. SETTING: University hospital surgical intensive care unit. PATIENTS: A total of 150 consecutive adult patients admitted to the surgery-anesthesiology intensive care unit. MATERIALS AND METHODS: The effects of surgery on serum albumin and total protein concentrations, and lymphocyte counts were investigated. This investigation was done by comparing the values before surgery with those values after surgery and by also comparing what happened after different types of surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: After surgery, decreases in serum albumin concentrations were significantly related to the estimated blood loss and acute gain in body weight from intravenous fluid resuscitation. The decreases in serum albumin and total protein concentrations were greater after elective abdominal surgery than after elective thoracic surgery. Total lymphocyte counts were significantly (< 1000 cells/mm3) reduced only in patients undergoing abdominal surgery. CONCLUSIONS: Serum albumin and total protein concentrations and total lymphocyte counts were significantly reduced by surgical injury, with significantly greater decreases seen after abdominal than thoracic surgery. These decreases were caused, in large part, by the volume of intravenous fluid used in resuscitation and blood loss. The changes in these variables are thus dependent on the type of surgical stress and the perioperative fluid therapy.

Abdomen↗
PubMed1977

Twenty-four-hour patterns in human performance, subjective and physiological variables and differences between morning and evening active subjects.

A study was undertaken to investigate differences between habitually morning active and evening active subjects as regards 24-hr patterns in physiological and subjective arousal and performance efficiency under conditions of 72 hr of sleep deprivation. The results were that very consistent 24-hr rhythmic were present in some of the performance variables, subjective alertness, oral temperature and urinary adrenaline excretion. No significant differences in 24-hr patterns could be detected between a group of habitually morning active and a group of evening active subjects. Significant correlations were obtained between oral temperature and some of the performance measures, while adrenaline excretion was not significantly correlated with performance. There were rather high correlations between subjective alertness ratings and some of the performances.

Adult↗
PubMed1998

Relationship between subjective fatigue and physiological variables in patients with chronic obstructive pulmonary disease.

Patients with chronic illnesses, such as chronic obstructive pulmonary disease (COPD), report an increase in the perception of fatigue in the clinical setting. Subjective fatigue associated with physiological factors has not been reported. The purpose of this study was to determine the relationship between subjective fatigue and pulmonary function, respiratory and peripheral muscle force and exercise capacity in patients with COPD. Nineteen patients with COPD participated in the study [mean (SD) FEV1 38% (17%) predicted]. Fatigue was measured with the Multidimensional Fatigue Inventory 20 (MFI-20) that includes the following subscale dimensions: general fatigue, physical fatigue, reduced activity, reduced motivation, and mental fatigue. The following physical variables were measured: forced expiratory volume in 1 s (FEV1), vital capacity (VC), maximal inspiratory peak pressure (PImax), symptom-limited bicycle exercise capacity (maximum workload) and maximal voluntary isometric muscle force of both left and right quadriceps (Qu), hamstrings (Ha), biceps (Bi) and triceps (Tr). The MFI-20 fatigue dimensions, reduced activity and reduced Motivation, are significantly correlated with FEV1 (% predicted) (r = -0.62, r = -0.55 respectively). No significant correlation was found between the dimensions of fatigue and maximum workload. In contrast the fatigue dimension, physical fatigue, shows significant correlations with seven of eight muscle forces measured (Qu left r = -0.49, right r = -0.54; Ha left r = -0.49, right r-0.38; Tr left r = -0.61, right r = -0.45; Bi left r = -0.46, right r = -0.48). Data from this study show that activity and physical dimensions of subjective fatigue are related to pulmonary function and skeletal muscle force in COPD patients. Interventions to improve skeletal muscle force might improve subjective fatigue in patients with COPD.

Exercise Tolerance↗