Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Hypoxic Blackout in Serial Freediving – Protective Mechanisms and Risk Factors

    Författare :Frank Pernett; Erika Schagatay; Glenn Björklund; Anton Westman; Mittuniversitetet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; breath-hold diving; diving response; hyperventilation; hypoxia; oxygen saturation; oxygen stores; pulse oximetry; sonography; splenic contraction.;

    Sammanfattning : Breath-hold diving or freediving exposes the body to stressors such as low oxygen and high carbon dioxide levels in the blood, increased hydrostatic pressure, and cold. The reduction in blood oxygen levels is considered a primary factor for loss of consciousness while diving. This is known as hypoxic blackout. LÄS MER

  3. 2. Cardiovascular and respiratory effects of apnea in humans

    Författare :Johan Andersson; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lung volume; breath-hold diving; Apnea; breath-holding; face immersion; cold stimulation; diving response; diving reflex; circulation; bradycardia; vasoconstriction; arterial blood pressure; cardiac output; spleen; respiration; splenic contraction; alveol; Physiology; Fysiologi; Respiratory system; Andningsorganen; Animal physiology; Djurfysiologi;

    Sammanfattning : This thesis deals with cardiovascular and respiratory effects of apneas in humans. During apnea (breath-holding), a number of interacting cardiovascular reflexes are initiated, and together these reflexes are called the “diving response”. LÄS MER

  4. 3. Protective Responses to Freediving Reveal High-Altitude Tolerance

    Författare :Pontus Holmström; Erika Schagatay; Angelica Lodin-Sundström; Harald K. Engan; Ola Eiken; Mittuniversitetet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Acclimatization; Acute Mountain Sickness; Adaptation; Apnea; Breath-hold diving; Cardiovascular diving response; High-altitude; Hypoxia tolerance; Spleen; Acklimatisering; Andhållningsdykning; Anpassning; Apné; Kardiovaskulära dykresponsen; Hög höjd; Hypoxitolerans; Hög-höjdssjukdom; Mjälte; Syrebärande kapacitet;

    Sammanfattning : High-altitude mountaineers - just as freedivers - are exposed to hypoxia. During freediving, the diving response leads to reduced oxygen consumption, and splenic contraction increases circulating hemoglobin concentration (Hb), which enhances freediving performance. LÄS MER

  5. 4. Neuropeptide Y Y1 receptor mechanisms in sympathetic vascular control

    Författare :Rickard E Malmström; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Sympathetic vasoconstriction; neuropeptide Y1 Y; receptor antagonists; BIBP 3226; SR 120107A; ischaemia; pig.;

    Sammanfattning : It was demonstrated that the Y1 receptor was the predominant vascular neuropeptide Y (NPY) receptor in pig kidney and hind limb as exogenous and endogenous NPY evoked vasoconstrictor responses that were almost or totally abolished by the selective non-peptide Y1 receptor antagonist, BIBP 3226. Furthermore, renal vasoconstriction was evoked by NPY and a peptide Y1 agonist, but not by a Y 2 agonist, and these responses were strongly reduced by another non-peptide Y, receptor antagonist, SR 120107A. LÄS MER