Introduction to the Cardiovascular System - part 4 docx

... rapidly, and to a smaller end-systolic volume (right figure). The reduced end-systolic volume leads to a compensatory decrease in end-diastolic volume; how- ever, the reduction in end-systolic volume ... between ve- locity of shortening and afterload (Fig. 4- 1 8). In other words, the greater the afterload, the slower the velocity of shortening. To further illustrate the f...

Ngày tải lên: 11/08/2014, 11:22

... the autoregulatory range). This is because of the strong capacity of these organs to autoregulate and their ability to escape sympathetic vaso- constrictor influences. The autoregulatory re- sponse ... potas- sium channels. Hyperpolarization leads to smooth muscle relaxation. Potassium ion appears to play a significant role in caus- 144 CHAPTER 7 Ch07_ 14 1-1 70_Klabunde 4/...

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... ions. The resistors represent the membrane resistances to the ions. Resistance equals the reciprocal of the ion conductances (i.e., 1/gX). Eq. 2-3 Eq. 2 -4 Eq. 2-5 Ch02_00 9-0 40 _Klabunde 4/ 21/ 04 10:53 ... gradient, to enter the cell. As the m-gates open, the h-gates begin to close; however, the m-gates open more rapidly than the h-gates close. The...

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... filament. Ch03_ 04 1-0 58_Klabunde 4/ 21/ 04 10:57 AM Page 43 wave of the QRS). About 20 milliseconds later, the mean electrical vector points down- ward toward the apex (vector 2), and heads to- ward the positive ... binds to b 1 -adrenoceptors, although it also can bind to ␣ 1 -adrenoceptors. Sympathetic nerve stimulation releases norepinephrine, which binds to ␤ 1 -ad...

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... causes the end-diastolic pressure- volume curve to shift up and to the left, as shown in Figure 4- 2 7. This shift will reduce the end-diastolic volume and increase the end-diastolic pressure at the ... in Figure 4- 6 , we find that the slope of the filling curve (the end-diastolic pressure-volume rela- tionship described in Figure 4- 4 ) increases dramatically at higher v...

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... reflex. Mechano- receptor Mechano- receptor Mechano- receptor Chemo- receptor Chemo- receptor Chemo- receptor 2 Chemo- receptor Chemo- receptor Nociceptor Nociceptor Various Proprio- ceptor Proprio- ceptor, Chemo- receptor Thermo- receptor Thermo- receptor Internal Carotids ... baroreceptors) enter the medulla at the nucleus trac- tus solitarius (NTS), which projects inhibitory interneuron...

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... Increasing the pO 2 difference increases the rate of diffusion. Ch08_17 1-1 84_ Klabunde 4/ 21/ 04 11 :45 AM Page 1 74 Ch07_ 14 1-1 70_Klabunde 4/ 21/ 04 11 :43 AM Page 170 Although the AV anastomoses are ... by the reflection coefficient (␴), a factor that represents the permeability of the cap- illary to the proteins responsible for generating the on- cotic pressur...

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... high. Ch09_18 5-2 14_ Klabunde 4/ 21/ 04 11 :47 AM Page 207 Ch08_17 1-1 84_ Klabunde 4/ 21/ 04 11 :45 AM Page 1 84 cannot operate to promote venous return and so cardiac output increases relatively little. Furthermore, the ... required to switch over to anaerobic gly- colysis for the production of ATP. Acidosis stimulates peripheral and central chemore- ceptors, leading to...

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... PHYSIOLOGICAL ACTIONS OF ENDOTHELIN-1 Endothelin-1 (ET-1) is synthesized from an endothelin precursor (big ET-1 or pro-ET-1) and cleaved to ET-1 by endothelin convert- ing enzyme (ECE) found on the endothelial cell ... at least partially offset the pressure-lowering effect of systemic vasodi- lation. CASE 9-3 Ch09_18 5-2 14_ Klabunde 4/ 21/ 04 11 :47 AM Page 211 nitric oxide is a...

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... be- cause of the large stroke volume ejected into the aorta. As long as the ventricle is not in fail- ure, normal end-systolic volumes can be sus- tained; however, the end-systolic volume in- creases ... Supplemental 6/3/ 04 6:31 PM Page 11 afterload (particularly aortic diastolic pres- sure) enables the end-systolic volume to de- crease slightly, but not enough to overcome th...

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