A reference handbook of the medical sciences, embracing the entire range of scientific and practical medicine and allied science . at, thelatter then exhibiting that independent rhythmspoken of above. In a somewhat similar manner thestimulation of the vagi, by affecting the rhj-thm ofthe auricles more than that of the ventricles maylead to a lack of coordination between the two, thespecially slowed auricles beating at one rate, theventricles at another. The question as to whetherthe vagus acts directly on the ventricles, as it doeson the auricles, or whether the effect on them is ofa secondary
A reference handbook of the medical sciences, embracing the entire range of scientific and practical medicine and allied science . at, thelatter then exhibiting that independent rhythmspoken of above. In a somewhat similar manner thestimulation of the vagi, by affecting the rhj-thm ofthe auricles more than that of the ventricles maylead to a lack of coordination between the two, thespecially slowed auricles beating at one rate, theventricles at another. The question as to whetherthe vagus acts directly on the ventricles, as it doeson the auricles, or whether the effect on them is ofa secondary nature caused by the changes in theauricle must for the present be left undecided. (6) Accelerator Nerves.—Diametrically oppositechanges are set up in the heart on stimulating theperipheral end of one of the accelerator nerves are characterized by their lesser irrita-bility, a longer latent period of stimulation and amore lasting after-effect when compared with thepneimidgastrics. With a suitable stimulus an accel-eration of the heart amounting to from five to onehundred per cent, may be obtained according to. Fio. 737.—Diagrammatic Repre-sentatioQ of the Cardiac Inhibitoryand Augmentor Fibers in the DogThe upper portion of the figure repre-sents the inhibitory,augmentor fibers. the initial rate at which the heart is beating. the case of the inhibitory fibers, the effect is of adual nature, the increase in rate being generallyaccompanied by an increase in the size and forceof both auricular and ventricular effect may. moreover, apjjear alone, so thatthe name augmentor has come to be used sideby side with that of accelerator for these fact, the suggestion has been offered that theheart really receives four distinct varieties of nervefibers throtigh its extrinsic nerves instead of two,corresponding to the several results obtained byartificial stimulation, namely, accelerating, retarding,augmenting, and depressing fibers. It is
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Keywords: ., bookauthorbuckalbe, bookcentury1900, bookdecade1910, bookyear1913
