The interrelationships of ventilation (V), tidal volume (VT), inspiratory (T1), expiratory (TE) and total breath (Ttot) durations, mean inspiratory (VT/TI) and expiratory (VT/TE) flows, and lung volumes were studied in normal subjects at rest and during exercise on a cycle ergometer. The ergometric load was increased by 10 W every minute, from zero W to 200 W. The TI/Ttot ratio increased with V in the range 15 to 60 1 X min-1, indicating that with increasing V the rate of increase of VT/TI decreased whereas that of VT/TE increased. Possible mechanisms responsible for the difference in behaviour of VT/TI and VT/TE are discussed. The VT-TI and VT-TE relationships both displayed three ranges with breakpoints at tidal volumes of about 1.4 and 2.4 1. The relations of TI and TE to end-inspiratory volume were approximately linear over the entire VT range studied, whereas the relations of TI and TE to end-expiratory volume showed three ranges with different characteristics. We conclude that the termination of inspiration during cycle exercise is dependent on volume-related afferent feedback from the lungs and/or chest walls, not only in the high but also in the low volume range.
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http://dx.doi.org/10.1111/j.1748-1716.1984.tb07381.x | DOI Listing |
Int J Surg
January 2025
Aging Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden.
Introduction: Lung function has been associated with cognitive decline and dementia, but the extent to which lung function impacts brain structural changes remains unclear. We aimed to investigate the association of lung function with structural macro- and micro-brain changes across mid- and late-life.
Methods: The study included a total of 37 164 neurologic disorder-free participants aged 40-70 years from the UK Biobank, who underwent brain MRI scans 9 years after baseline.
Adv Clin Exp Med
January 2025
Clinic of Children's Diseases, Institute of Clinical Medicine, Faculty of Medicine, Vilnius University, Lithuania.
Background: The number of infants born via cesarean section (CS) is increasing globally due to medical and cultural reasons.
Objectives: This study aimed to determine the effect of the mode of delivery on early lung aeration in newborns using electrical impedance tomography (EIT).
Material And Methods: The case-control study was conducted from December 2020 to April 2021.
Heart Lung
January 2025
Department of Preventive Medicine, Shantou University Medical College, Shantou, Guangdong 515041, China. Electronic address:
Background: Evidence for a relation between residential greenspace and respiratory health is scarce and controversial.
Objectives: The purpose of this study was to explore the association between residential greenspace and its interaction with particulate matter (PM) and risk of chronic obstructive pulmonary disease (COPD) and lung function.
Methods: A total of 3,759 adults were recruited from Wenzhou in this study.
Sci Rep
January 2025
School of Computing, SASTRA Deemed University, Thanjavur, Tamil Nadu, India.
Mechanical ventilation is the process through which breathing support is provided to patients who face inconvenience during respiration. During the pandemic, many people were suffering from lung disorders, which elevated the demand for mechanical ventilators. The handling of mechanical ventilators is to be done under the assistance of trained professionals and demands the selection of ideal parameters.
View Article and Find Full Text PDFBr J Radiol
January 2025
Department of Radiology, The First Affiliated Hospital of Xi'an Jiaotong University, Yanta Western Road, Xi'an, Shannxi, 710061.
Purpose: To explore the effect of different reconstruction algorithms (ASIR-V and DLIR) on image quality and emphysema quantification in chronic obstructive pulmonary disease (COPD) patients under ultra-low-dose scanning conditions.
Materials And Methods: This prospective study with patient consent included 62 COPD patients. Patients were examined by pulmonary function test (PFT), standard-dose CT (SDCT) and ultra-low-dose CT (ULDCT).
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