Search results for "Respiratory Physiology"
showing 10 items of 363 documents
MR angiography of the pedal arteries with gadobenate dimeglumine, a contrast agent with increased relaxivity, and comparison with selective intraarte…
2007
Purpose To compare gadobenate dimeglumine (Gd-BOPTA)–enhanced MR angiography (i.e., contrast-enhanced MRA [CE-MRA]) of the pedal vasculature with selective digital subtraction angiography (DSA) in patients with peripheral arterial occlusive disease (PAOD). Materials and Methods A total of 22 patients with PAOD were prospectively examined at 1.5T. For contrast enhancement, 0.1 mmol/kg body weight of Gd-BOPTA were applied. MRA consisted of dynamic imaging with acquisition of six consecutive data sets. Acquisition time for each data set was 24 seconds, voxel size was 1.0 × 1.0 × 1.3 mm3. A total of 20 out of 22 patient underwent selective DSA, two patients fine-needle DSA. DSA and MRA were per…
Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study
2021
BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (V(T)). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients. OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference. DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries. MAIN OUTCOME MEASURES: Women and men were compared with respect to use o…
Investigation into the role of phosphodiesterase IV in bronchorelaxation, including studies with human bronchus.
1993
1. We have investigated the role of cyclic nucleotide phosphodiesterase IV (PDE IV) in the relaxation of human bronchus and guinea-pig trachea in vitro and in guinea-pigs in vivo. 2. Functional studies showed that the selective PDE IV inhibitors, rolipram and denbufylline, relaxed human and guinea-pig preparations in vitro. 3. Two clinically used xanthine non-selective PDE inhibitors, theophylline and pentoxifylline, were also effective in these preparations, but were much less potent than the selective agents used. 4. The rank order of potency for the four PDE inhibitors in both species was similar. 5. Biochemical studies indicated that PDE IV was the major PDE isoform present in the human…
Cardiovascular and autonomic responses to physiological stressors before and after six hours of water immersion
2013
The physiological responses to water immersion (WI) are known; however, the responses to stress following WI are poorly characterized. Ten healthy men were exposed to three physiological stressors before and after a 6-h resting WI (32–33°C): 1) a 2-min cold pressor test, 2) a static handgrip test to fatigue at 40% of maximum strength followed by postexercise muscle ischemia in the exercising forearm, and 3) a 15-min 70° head-up-tilt (HUT) test. Heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), cardiac output (Q̇), limb blood flow (BF), stroke volume (SV), systemic and calf or forearm vascular resistance (SVR and CVR or FVR), baroreflex sensitivity (BRS), and HR variabili…
Is Moderate Intensity Cycling Sufficient to Induce Cardiorespiratory and Biomechanical Modifications of Subsequent Running?
2017
Walsh, JA, Dawber, JP, Lepers, R, Brown, M, and Stapley, PJ. Is moderate intensity cycling sufficient to induce cardiorespiratory and biomechanical modifications of subsequent running? J Strength Cond Res 31(4): 1078-1086, 2017-This study sought to determine whether prior moderate intensity cycling is sufficient to influence the cardiorespiratory and biomechanical responses during subsequent running. Cardiorespiratory and biomechanical variables measured after moderate intensity cycling were compared with control running at the same intensity. Eight highly trained, competitive triathletes completed 2 separate exercise tests; (a) a 10-minute control run (no prior cycling) and, (b) a 30-minut…
The effect of two low doses of aspirin on whole blood thromboxane and prostacyclin generation in healthy subjects
1983
SummaryThe effects of two low doses of aspirin (20 mg and 100 mg) on prostacyclin and thromboxane formation during whole blood clotting were studied in 8 healthy volunteers.A single 100 mg aspirin dose caused more than 90% reduction of both serum TXB2 and 6-keto-PGF1α; a single 20 mg dose of aspirin inhibited serum TXB2 more than 6-keto-PGF1α but effects on these two products could not be completely dissociated.However, the effect of a single 20 mg aspirin dose on serum TXB2, was of much longer duration than its inhibitory effect on PGI2 synthesis during whole blood clotting.
Temporal relationship between nocturnal erections and rapid eye movement episodes in healthy men.
2003
The exact temporal relationship between spontaneous nocturnal erections and rapid eye movement (REM) sleep was studied in healthy men with the aim of creating a basis for a more sophisticated analysis of nocturnal erection measurements in physiological research and clinical applications. The vast majority of erectile events was coupled to REM episodes, where the latency between the beginning of erections and REM episodes showed a large variability. Moreover, a correlation analysis revealed a highly significant decrease of the latency over the course of the night. The time variant properties of the coupling between erections and REM sleep point to more complex dynamics of the central control…
Anti-diphtheria antibody seroprotection rates are similar 10 years after vaccination with dTpa or DTPa using a mathematical model
2003
The reduced antigen content diphtheria, tetanus and pertussis (dTpa) vaccine (Boostrixtrade mark) has been shown to induce a strong booster response to all the vaccine components in 4-6 year olds. However, anti-diphtheria antibody levels were observed to be lower when compared to the "full strength" paediatric DTPa vaccine. To assess the impact of this difference on long-term protection, a mathematical model was developed to predict diphtheria antibody decay over time. The model was based on a linear decrease in log-transformed antibody concentrations after the first year post-vaccination. When applied to data collected 3.5 years after vaccination of 4-6 year olds with either DTPa or dTpa, …
Pituitary-adrenal responses to ovine corticotropin-releasing factor in polycystic ovary syndrome and in other hyperandrogenic patients.
1990
This study was carried out to further characterize the pituitary-adrenal androgen responses of hyperandrogenic patients with 'classic' polycystic ovary syndrome (PCO) and others who were less distinctive and have been called 'PCO-like'. PCO-like patients differed from PCO only in that serum luteinizing hormone (LH) levels were normal and anovulation was not consistent. Ovine corticotropin-releasing factor (CRF) resulted in normal responses of adrenocorticotropic hormone and cortisol in the two groups when compared to controls, while androstenedione (delta 4A) and dehydroepiandrosterone (DHEA) responses were significantly elevated. There were no differences in the responses of PCO and PCO-li…
Fluctuation of the left ventricular ejection fraction in patients with HER2-positive early breast cancer treated by 12 months of adjuvant trastuzumab.
2018
Abstract Background Cardiac toxicity with a decrease of the left ventricular ejection fraction (LVEF) is the main side effect induced by trastuzumab. This study reports the fluctuation of LVEF over the 12 months of adjuvant trastuzumab in PHARE trial (NCT00381901). Methods LVEF assessment was performed every 3 months while patients received trastuzumab and after completion of treatment over the first 2 years and then every 6 months afterwards. The fluctuations of LVEF over time were described and a logistic regression model was performed investigating associated factors to LVEF perfect recovery at baseline value. Results A total of 1631 patients who received 12 months of trastuzumab from PH…