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Social and Behavioral Sciences Commons

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Articles 1 - 4 of 4

Full-Text Articles in Social and Behavioral Sciences

Progenitor Cells And Age: Can We Fight Aging With Exercise?, Sarah Witkowski, James M. Hagberg Mar 2007

Progenitor Cells And Age: Can We Fight Aging With Exercise?, Sarah Witkowski, James M. Hagberg

Exercise and Sport Studies: Faculty Publications

No abstract provided.


Transcranial Doppler Estimation Of Cerebral Blood Flow And Cerebrovascular Conductance During Modified Rebreathing, Jurgen A.H.R. Claassen, Rong Zhang, Qi Fu, Sarah Witkowski, Benjamin D. Levine Mar 2007

Transcranial Doppler Estimation Of Cerebral Blood Flow And Cerebrovascular Conductance During Modified Rebreathing, Jurgen A.H.R. Claassen, Rong Zhang, Qi Fu, Sarah Witkowski, Benjamin D. Levine

Exercise and Sport Studies: Faculty Publications

Clinical transcranial Doppler assessment of cerebral vasomotor reactivity (CVMR) uses linear regression of cerebral blood flow velocity (CBFV) vs. end-tidal CO2 (PETCO2) under steady-state conditions. However, the cerebral blood flow (CBF)-PETCO2 relationship is nonlinear, even for moderate changes in CO2. Moreover, CBF is increased by increases in arterial blood pressure (ABP) during hypercapnia. We used a modified rebreathing protocol to estimate CVMR during transient breath-by-breath changes in CBFV and PETCO2. Ten healthy subjects (6 men) performed 15 s of hyperventilation followed by 5 min of rebreathing, with supplemental O2 to maintain arterial oxygen saturation constant. To minimize effects of changes …


Sex Differences In The Onset Of Seasonal Reproductive Quiescence In Hamsters, Annaliese K. Beery, Justin J. Trumbull, Jyeming M. Tsao, Ruth M. Costantini, Irving Zucker Jan 2007

Sex Differences In The Onset Of Seasonal Reproductive Quiescence In Hamsters, Annaliese K. Beery, Justin J. Trumbull, Jyeming M. Tsao, Ruth M. Costantini, Irving Zucker

Neuroscience: Faculty Publications

Day length is the primary cue used by many mammals to restrict reproduction to favourable spring and summer months, but it is unknown for any mammal whether the seasonal loss of fertility begins at the same time and occurs at the same rate in females and males; nor it established whether the termination of mating behaviour in males and females coincides with the loss of fertility. We speculated that females, owing to their greater energetic investment in reproduction, are the limiting sex in terminating offspring production in short days (SDs). Oestrous cycles and production of young were monitored in Syrian …


Cerebral Hemodynamics After Short- And Long-Term Reduction In Blood Pressure In Mild And Moderate Hypertension, Rong Zhanf, Sarah Witkowski, Qi Fu, Jurgen A.H.R. Claassen, Benjamin D. Levine Jan 2007

Cerebral Hemodynamics After Short- And Long-Term Reduction In Blood Pressure In Mild And Moderate Hypertension, Rong Zhanf, Sarah Witkowski, Qi Fu, Jurgen A.H.R. Claassen, Benjamin D. Levine

Exercise and Sport Studies: Faculty Publications

This study tested the hypothesis that acute reduction in blood pressure (BP) at the initial stage of antihypertensive therapy compromises brain perfusion and dynamic cerebral autoregulation in patients with hypertension. Cerebral blood flow velocity and BP were measured in patients with mild and moderate hypertension and in healthy volunteers at baseline upon reduction of BP within 1 to 2 weeks of administration of losartan/hydrochlorothiazide and after 3 to 4 months of treatment. The transfer function between beat-to-beat changes in BP and cerebral blood flow velocity was estimated to assess dynamic autoregulation. After 1 to 2 weeks of treatment, BP was …