The Experts below are selected from a list of 216 Experts worldwide ranked by ideXlab platform

Jerome Engel - One of the best experts on this subject based on the ideXlab platform.

  • high frequency oscillations recorded in human medial temporal lobe during sleep
    Annals of Neurology, 2004
    Co-Authors: Richard J Staba, Charles L Wilson, Anatol Bragin, Donald Jhung, Itzhak Fried, Jerome Engel
    Abstract:

    The presence of fast ripple oscillations (FRs, 200 –500Hz) has been confirmed in rodent epilepsy models but has not been observed in nonepileptic rodents, suggesting that FRs are associated with epileptogenesis. Although studies in human epileptic patients have reported that both FRs and ripples (80 –200Hz) chiefly occur during non–rapid eye movement sleep (NREM), and that ripple oscillations in human hippocampus resemble those found in nonprimate slow wave sleep, quantitative studies of these oscillations previously have not been conducted during polysomnographically defined sleep and waking states. Spontaneous FRs and ripples were detected using automated Computer Techniques in patients with medial temporal lobe epilepsy during sleep and waking, and results showed that the incidence of ripples, which are thought to represent normal activity in animal and human hippocampus, was similar between epileptogenic and nonepileptogenic temporal lobe, whereas rates of FR occurrence were significantly associated with epileptogenic areas. The generation of both FRs and ripples showed the highest rates of occurrence during NREM sleep. During REM sleep, ripple rates were lowest, whereas FR rates remained elevated and were equivalent to rates observed during waking. The predominance of FRs within the epileptogenic zone not only during NREM sleep, but also during epileptiformsuppressing desynchronized episodes of waking and REM sleep supports the view that FRs are the product of pathological neuronal hypersynchronization associated with seizure-generating areas. Ann Neurol 2004;56:108 –115

  • high frequency oscillations recorded in human medial temporal lobe during sleep
    Annals of Neurology, 2004
    Co-Authors: Richard J Staba, Charles L Wilson, Anatol Bragin, Donald Jhung, Itzhak Fried, Jerome Engel
    Abstract:

    The presence of fast ripple oscillations (FRs, 200-500 Hz) has been confirmed in rodent epilepsy models but has not been observed in nonepileptic rodents, suggesting that FRs are associated with epileptogenesis. Although studies in human epileptic patients have reported that both FRs and ripples (80-200 Hz) chiefly occur during non-rapid eye movement sleep (NREM), and that ripple oscillations in human hippocampus resemble those found in nonprimate slow wave sleep, quantitative studies of these oscillations previously have not been conducted during polysomnographically defined sleep and waking states. Spontaneous FRs and ripples were detected using automated Computer Techniques in patients with medial temporal lobe epilepsy during sleep and waking, and results showed that the incidence of ripples, which are thought to represent normal activity in animal and human hippocampus, was similar between epileptogenic and nonepileptogenic temporal lobe, whereas rates of FR occurrence were significantly associated with epileptogenic areas. The generation of both FRs and ripples showed the highest rates of occurrence during NREM sleep. During REM sleep, ripple rates were lowest, whereas FR rates remained elevated and were equivalent to rates observed during waking. The predominance of FRs within the epileptogenic zone not only during NREM sleep, but also during epileptiform-suppressing desynchronized episodes of waking and REM sleep supports the view that FRs are the product of pathological neuronal hypersynchronization associated with seizure-generating areas.

Thomas Moore - One of the best experts on this subject based on the ideXlab platform.

  • diurnal rhythms in fetal urine flow vascular pressures and heart rate in sheep
    American Journal of Physiology-regulatory Integrative and Comparative Physiology, 1991
    Co-Authors: Robert A. Brace, Thomas Moore
    Abstract:

    Conflicting indirect data exist as to whether diurnal variations occur in fetal urine flow rate. In addition, the extent of diurnal rhythms in fetal venous pressure or arterial pressure is unknown, although 24-h rhythms do exist in fetal heart rate. In the present study, we used on-line Computer Techniques to continuously monitor these variables in chronically catheterized ovine fetuses. Fetal urine flow rate and vascular pressures were successfully recorded in 6 of 11 animals over a 24-h period on 21 days out of a total of 45 days of monitoring. We found highly significant diurnal variations in fetal urine flow rate (P less than 10(-6). Hourly means displayed a maximum at 2130 h and a minimum at 1330 h with a maximum amplitude of 28 +/- 5% of the 24-h mean. A secondary maximum (at 0630 h) and minimum (at 0330 h) of smaller amplitude also occurred. There were simultaneous and highly significant (P less than 0.0001) diurnal rhythms in fetal arterial pressure (+/- 2%), venous pressure (+/- 7%), and heart rate (+/- 5%). The maxima in arterial pressure and heart rate occurred within 1 h of the maximum in urine flow, while venous pressure changes were opposite those in arterial pressure. Hourly mean urine flow correlated significantly with arterial pressure but not venous pressure or heart rate, suggesting that the observed 24-h variations in fetal urine flow rate may be partially mediated by a pressure diuresis.(ABSTRACT TRUNCATED AT 250 WORDS)

Richard J Staba - One of the best experts on this subject based on the ideXlab platform.

  • high frequency oscillations recorded in human medial temporal lobe during sleep
    Annals of Neurology, 2004
    Co-Authors: Richard J Staba, Charles L Wilson, Anatol Bragin, Donald Jhung, Itzhak Fried, Jerome Engel
    Abstract:

    The presence of fast ripple oscillations (FRs, 200 –500Hz) has been confirmed in rodent epilepsy models but has not been observed in nonepileptic rodents, suggesting that FRs are associated with epileptogenesis. Although studies in human epileptic patients have reported that both FRs and ripples (80 –200Hz) chiefly occur during non–rapid eye movement sleep (NREM), and that ripple oscillations in human hippocampus resemble those found in nonprimate slow wave sleep, quantitative studies of these oscillations previously have not been conducted during polysomnographically defined sleep and waking states. Spontaneous FRs and ripples were detected using automated Computer Techniques in patients with medial temporal lobe epilepsy during sleep and waking, and results showed that the incidence of ripples, which are thought to represent normal activity in animal and human hippocampus, was similar between epileptogenic and nonepileptogenic temporal lobe, whereas rates of FR occurrence were significantly associated with epileptogenic areas. The generation of both FRs and ripples showed the highest rates of occurrence during NREM sleep. During REM sleep, ripple rates were lowest, whereas FR rates remained elevated and were equivalent to rates observed during waking. The predominance of FRs within the epileptogenic zone not only during NREM sleep, but also during epileptiformsuppressing desynchronized episodes of waking and REM sleep supports the view that FRs are the product of pathological neuronal hypersynchronization associated with seizure-generating areas. Ann Neurol 2004;56:108 –115

  • high frequency oscillations recorded in human medial temporal lobe during sleep
    Annals of Neurology, 2004
    Co-Authors: Richard J Staba, Charles L Wilson, Anatol Bragin, Donald Jhung, Itzhak Fried, Jerome Engel
    Abstract:

    The presence of fast ripple oscillations (FRs, 200-500 Hz) has been confirmed in rodent epilepsy models but has not been observed in nonepileptic rodents, suggesting that FRs are associated with epileptogenesis. Although studies in human epileptic patients have reported that both FRs and ripples (80-200 Hz) chiefly occur during non-rapid eye movement sleep (NREM), and that ripple oscillations in human hippocampus resemble those found in nonprimate slow wave sleep, quantitative studies of these oscillations previously have not been conducted during polysomnographically defined sleep and waking states. Spontaneous FRs and ripples were detected using automated Computer Techniques in patients with medial temporal lobe epilepsy during sleep and waking, and results showed that the incidence of ripples, which are thought to represent normal activity in animal and human hippocampus, was similar between epileptogenic and nonepileptogenic temporal lobe, whereas rates of FR occurrence were significantly associated with epileptogenic areas. The generation of both FRs and ripples showed the highest rates of occurrence during NREM sleep. During REM sleep, ripple rates were lowest, whereas FR rates remained elevated and were equivalent to rates observed during waking. The predominance of FRs within the epileptogenic zone not only during NREM sleep, but also during epileptiform-suppressing desynchronized episodes of waking and REM sleep supports the view that FRs are the product of pathological neuronal hypersynchronization associated with seizure-generating areas.

Duncan Cramer - One of the best experts on this subject based on the ideXlab platform.

  • fundamental statistics for social research step by step calculations and Computer Techniques using spss for windows
    1998
    Co-Authors: Duncan Cramer
    Abstract:

    From the Publisher: An updated version of Introducing Statistics for Social Research (1994), this volume describes when to apply, how to calculate and how to interpret a comprehensive selection of statistical procedures used in social science. Ranging from chi-square and the t-test to analysis of covariance and multiple regression, Duncan Cramer shows how to calculate these procedures by hand as well as with the Computer program SPSS for Windows. Fundamental Statistics for Social Research covers a wider choice of statistics and includes tests not normally found in introductory texts.

  • basic statistics for social research step by step calculations Computer Techniques using minitab
    1997
    Co-Authors: Duncan Cramer
    Abstract:

    This accessible introdution to statistics using the program Minitab explains when to apply and how to calculate and interpret a wide range of statistical procedures commonly used in the social sciences. Keeping statistical symbols and formulae to a minimum and using simple examples, this book: * Assumes no prior knowledge of statistics or computing * Includes a concise introduction to the program Minitab * Describes a wider range of tests than other introductory texts * Contains a comprehensive range of exercises with answers. Basic Statistics for Social Research will prove an invaluable introductory statistics text for students, and a useful resource for graduates and professionals engaged in research in the social sciences.

Robert A. Brace - One of the best experts on this subject based on the ideXlab platform.

  • diurnal rhythms in fetal urine flow vascular pressures and heart rate in sheep
    American Journal of Physiology-regulatory Integrative and Comparative Physiology, 1991
    Co-Authors: Robert A. Brace, Thomas Moore
    Abstract:

    Conflicting indirect data exist as to whether diurnal variations occur in fetal urine flow rate. In addition, the extent of diurnal rhythms in fetal venous pressure or arterial pressure is unknown, although 24-h rhythms do exist in fetal heart rate. In the present study, we used on-line Computer Techniques to continuously monitor these variables in chronically catheterized ovine fetuses. Fetal urine flow rate and vascular pressures were successfully recorded in 6 of 11 animals over a 24-h period on 21 days out of a total of 45 days of monitoring. We found highly significant diurnal variations in fetal urine flow rate (P less than 10(-6). Hourly means displayed a maximum at 2130 h and a minimum at 1330 h with a maximum amplitude of 28 +/- 5% of the 24-h mean. A secondary maximum (at 0630 h) and minimum (at 0330 h) of smaller amplitude also occurred. There were simultaneous and highly significant (P less than 0.0001) diurnal rhythms in fetal arterial pressure (+/- 2%), venous pressure (+/- 7%), and heart rate (+/- 5%). The maxima in arterial pressure and heart rate occurred within 1 h of the maximum in urine flow, while venous pressure changes were opposite those in arterial pressure. Hourly mean urine flow correlated significantly with arterial pressure but not venous pressure or heart rate, suggesting that the observed 24-h variations in fetal urine flow rate may be partially mediated by a pressure diuresis.(ABSTRACT TRUNCATED AT 250 WORDS)