Heart rate description

Duration of observation (Table 6) for each subject was lengthy and required a total more than 300 subject days of testing, considering that each subject (in groups of 2-4 as a rule) occupied a test cubicle for an average of five days. Vital signs, including pupil size, heart rate, blood pressure and performance on NF and VITA, were measured at 1, 2, 3, 4, 6, 8, 10, 12, 16 and every four hours thereafter until recovery. The nurse entered full descriptions of behavior as often as possible. 

Fig. 4. Change in heart rate produced by apomorphine in the rat. Slowing of heart rate predominates at low dmg concentrations, while tachycardia is most prominent at high steady-state concentration. Two sigmoid Emax models have been combined for the PK-PD analysis. Cp(50) corresponds to Cso% (From Paalzow LK, Paalzow GHM, Tfelt-Hansen P Variability in bioavailability concentration versus effect. In Rowland M, Sheiner LB, Steimer J-L, editors. Variability in dmg therapy description, estimation, and control. New York Raven Press 1985.)...

The other changes suggest a similar shift toward sympathetic activation. In Aserinsky and Kleitman s first published description of REM sleep (Science, 1953), they reported that heart rate and respiratory rate both increased. Soon thereafter, Frederick Snyder showed that systolic blood pressure also increased, sometimes to alarming levels, in REM. Psychotogens raise heart rate and blood pressure, too. 

Brown et al., 1997). This is in line with the general notion that animals with a smaller body size have a faster heart rate. The circulation time (between any two points of the body) is shorter in infants and children than in adults, owing to small body size coupled with faster heart rate. Heart rate falls gradually as a function of age between birth and adolescence (Shock, 1944 Iliff Lee, 1952), with no apparent sex difference until the age of 10. Quantitative descriptions of the relationship between cardiac output and body surface area and body height have been established for infants, children, and adults (Cayler et al., 1963 Krovetz et al., 1969). 

The authors suggested that torsade de pointes induced by intravenous amiodarone depended on heart rate during a bout of bradycardia, while that after oral amiodarone depended on increased sympathetic nervous system activity, and that therefore different electrophysiological mechanisms had been at play. However, it is by no means clear from their description of this case that that was so. They did not report plasma concentrations of amiodarone or desethylamiodarone, its active metabolite. 

Exercise category Mean heart rate (beats/min) Description (hours/week) Types of events... 

As Antzelevitch and Francis (2004) noted, inherited LQTS was first described in individuals with structurally normal hearts six decades ago by Jervell and Lange-Nielsen (1957). In contrast, inherited SQTS was first proposed as a new inherited clinical syndrome less than two decades ago by Gussak and colleagues (2000). Included in their clinical report was a description of three manbers of one family a 17-year-old female, her 21-year-old brother, and their 51-year-old mother. The sister s QT interval was 280 msec at a heart rate of 69, the brother s QT interval was 272 msec at a heart rate of 58, and the mother s QT interval was 260 msec at a heart rate of 74. The shorter than usual QT interval was associated in the sister with several episodes of paroxysmal atrial fibrillation requiring electrical cardioversion. Similar ECG changes seen in a 37-year-old individual not related to the family were associated with sudden cardiac death (Gussak et al. 2000). 

Shroff SG, Janicki JS, Weber KT (1983a) The importance of internal resistance in the description of ventricular mechanics. Bull Philadelphia Phys Soc 2 32-43 Shroff SG, Janicki JS, Weber KT (1983b) Left ventricular systolic dynamics in terms of its chamber mechanical properties. Am J Physiol 245 H110-H124 Shroff SG, Weber KT, Janicki JS (1984) End systolic relations Their usefulness and limitations in assessing left ventricular contractile state. Int J Cardiol 5 253-259 Suga H, Sagawa K, Shoukas AA (1973) Load independence of the instantaneous pressure-volume ratio of the canine left ventricle and effects of epinephrine and heart rate on the ratio. Circ Res 32 314-322... 

Notice again that solving the rate-of-change form of the mass balance requires more inform.ation (here the rate of reaction) and more effort than solving the difference form of the mass balance. However, we also get more information—the amount of each species present as a function of time. In Sec. 2.4, which is optional and more difficult, we consider another, even deeper level of description, where not only is time allowed to vary, but the system is.not spatially homogeneous that is, the composition in the reactor varies from point to point. However, this section is not for the faint-hearted and is best considered after a course iri fluid mechanics. B... 

The information about the tendenqf for corrosion to occur that can be obtained from thermodynamic calculations is important and useful. However, most of the science and engineering aspects in the field of corrosion focus on knowing and reducing the rate of corrosion. The rate of corrosion is not addressed by thermodynamics it falls instead within the purview of kinetics. So the kinetics of electrochemical reactions in general, and corrosion reactions specifically, are at the heart of the subject of corrosion. This chapter will introduce electrochemical kinetics at a simple level, with sufficient detail to develop the concept of mixed potential theory. The interested reader is referred to other volumes of this encyclopedia and to textbooks in corrosion [1-9] for a more detailed description. The kinetic underpinnings of some of the electrochemical techniques for determination of corrosion rate will also be presented. The influence of transport on the rates of electrochemical reactions will be discussed in the next chapter (see Chapter 1.4). 

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