A rush of blood towards the heart is thereby set up, and the blood streams through the perforated diaphragm into the pericardial chamber.
Graber has explained the action of the pericardial diaphragm and chamber in the following way.
Scattered over the upper surface of the pericardial diaphragm are groups of cells, similar to the fat-masses of the perivisceral space.
The heart lies in a pericardial chamber, which is bounded above by the terga and the longitudinal tergal muscles; below by a fenestrated membrane, the pericardial diaphragm.
The exceptions relate chiefly to the alary muscles of the pericardial septum.
From the perivisceral space the blood enters the pericardialsinus by the apertures in its floor, and returns thence by the lateral inlets into the heart.
The pericardial diaphragm, or floor of the pericardium, is continuous, except for small oval openings scattered over its surface.
Muscles of Dorsal Wall, with the Heart and Pericardial Tendons.
Sheets of the same substance lie in the pericardial sinus on each side of the heart.
In this way the progressive and rhythmical contraction of the chambers impels a steady forward current of blood, allowing an intermittent stream to enter from the pericardial space, but preventing regurgitation.
Moreover, we find comparatively few tracheal tubes in the pericardial chamber, and can discover no proof that in the Cockroach the fat-cells adjacent to the heart have any special respiratory character.
Precisely the same arrangement of veno-pericardial muscles and of longitudinal venous collecting sinuses occurs in the scorpions.
The veno-pericardial muscles in Limulus are limited by the extent of the heart, they do not extend beyond the anterior limit of the heart.
On the contrary, his experimental work indicated that each veno-pericardial muscle received its motor supply from the corresponding mesosomatic ganglion.
Carlson, at my request, endeavoured in the living Limulus to see whether stimulation of the pericardial nerve caused contraction of the veno-pericardial muscles, but was unable to find any such effect.
If they exist and if they are in accordance with those to the heart, then they ought to run in the pericardial nerve, and would naturally reach the veno-pericardial muscles by the segmental branches of the pericardial nerve.
All these reasons point to the same conclusion: the tubular muscles in Ammocoetes are the successors of the veno-pericardial system of muscles.
At present the homology suggested is not complete, for there is no evidence as yet that the veno-pericardial muscles have anything to do with the pericardial nerve.
Collect a sample of pericardial fluid in a pipette for microscopical and cultural examination.
Raise the pericardial sac in a fresh pair of forceps and burn through this structure with a searing iron.
Pericardial chamber, the chamber around the heart; see Sec.
At the constrictions between the chambers are paired slits, through which the blood passes from the surrounding pericardial sinus.
After bathing the various tissues and organs, the blood returns dorsalwards into the pericardial sinus through fine perforations of its floor, and so makes its way into the heart again.
The quantity of pericardial fluid is sometimes increased in septicæmia, and is generally somewhat thickened, cloudy, and slightly tinged with blood.
Sometimes, it is said, a pericardial friction sound may be heard, which is attributed to the dryness of the pericardium.
The pleural and pericardial sacs are more or less distended with serum, thus mechanically embarrassing the action of the organs they contain.
The pericardial milk-spots and thickenings, the tendinous or semi-cartilaginous, indurated patches of serous membranes and of the intima of arteries, are all regarded as manifestations of a chronic inflammation of these tissues.
Diagram of section of the pericardial sac*, heart removed.
Pierce its lower portion and collect the pericardial fluid.
The heart does not lie inside of the pericardial sac, as seems at first glance to be the case, but its relation to this space is like that of the hand to the inside of an empty sack which is laid around it (Fig.
The hindermost constriction (uppermost in my figure) lies just in front of thepericardial cavity; and separates the Cyathozooid from the four ascidiozooids.
Figure A shews the separation of the body cavity from the pericardial cavity by a horizontal septum in which runs the ductus Cuvieri; on the left side is seen the narrow passage which remains connecting the two cavities.
The septum is soon continued forwards so as completely to separate the ventral pericardial and the dorsal body cavity in front, the pericardial cavity extending at this period considerably further forwards than the body cavity.
It is continued forward into the head (Oellacher), and part of it becomes separated off from the remainder as the pericardial cavity.
The pericardial cavity is completely contained within the Cyathozooid, and the heart itself (ht) has become formed by an involution of the walls of the cavity.
A right and left lateral prolongation of the pericardial cavity.
By these changes the pericardial cavity is converted into a closed bag, completely surrounded at its sides by the two lateral halves of the body cavity, which were primitively placed dorsally to it.
Ventrally the liver is united with the abdominal wall, but laterally passages are left by which the pericardial and body cavities continue to communicate.
The heart and pericardial cavity are seen to the left.
This enlargement takes place partly by the elongation of the posterior mediastinum, but still more by the two divisions of the body cavity which contain the lungs extending themselves ventrally round the outside of the pericardial cavity.
The pericardial area is early differentiated from the rest of the coelom and at first lies in front of the neural and bucco-pharyngeal area; here the mesoderm stretches right across the mid-line, which it does not in front and behind.
Laterally the pericardial cavity communicates with the general cavity of the coelom, but with the growth of the Cuvierian ducts (see development of veins) these communications disappear.
The pericardial cavity is separated from the peritoneal cavity by a thick muscular wall against which the liver abuts.
At the anterior end of the body in front of the liver and between the sets of gills note the small pericardial cavity within which is contained the heart.
Solenomya, in which the gonad opens into the reno-pericardial duct.
This investment, which occurs also in many Filibranchia, forms the pericardial glands, comparable to the pericardial accessory glandular growths of Cephalopoda.
A, Pericardium opened dorsally so as to expose the heart and the floor of the pericardial chamber d.
In Unionidae and several other forms the pericardial glands are extended into diverticula of the pericardium which penetrate the mantle and constitute the organ of Heber.
But the generative products do not pass through the whole length of the renal tube: there is a direct opening from the pericardial end of the tube to the distal end, and the ova or sperms pass through this.
Opening in pairs in each somite, right and left into the pericardial sinus are large veins, which bring the blood respectively from the gill-books and the lung-books to that chamber, whence it passes by the ostia into the heart.
In both animals the wall of the pericardial sinus is connected by vertical muscular bands to the wall of the ventral venous sinus (its lateral expansions around the lung-books in Scorpio) in each somite through which the pericardium passes.
The great pericardial sinus is strongly developed in both animals.
The diaphragm, especially that part of it underlying the pericardial sacs, had undergone marked fibroid degeneration.
Irregularities of the pericardial false membrane are so common that nothing but the close and universal adhesions would raise any question of these relations.
This cachectic dropsy in rare cases becomes excessive and leads to anasarca, with serous effusion in the peritoneal, pleural, and pericardial sacs.
The extraction was very slow in order to allow of coagulation along the course of the wound in the heart, and to guard against hemorrhage into the pericardial sac, which is so often the cause of death in punctured wounds of this organ.
An incision eight inches long was made over the 4th rib, six inches of the rib were resected, the bleeding intercostal artery was ligated, the blood was turned out of the pericardial cavity, this cavity being irrigated with hot water.
When the pericardial sac was incised, a teaspoonful of turbid fluid oozed out, and the needle was felt in an oblique position in the right ventricle.
Zillner attributed this circumstance to the small size of the wound, atheroma and degeneration of the aorta and slight retraction of the inner coat, together with a possible plugging of the pericardial opening.
Quoted by Fournier, Lapeyronnie has seen worms in the pericardial sac, and also in the ventricle.
These cavities afterwards join and form the simple pericardial cavity, and are therefore called by Kolliker the "primitive pericardial cavities.
Pericardium indicated by a dotted outline--at its right side are seen the two reno-pericardial pores.
But the amount of the hemorrhage may not be sufficient for this result, and still cause death by disturbing the function of the organ into which it is effused, as in the brain or in the pleural or pericardial cavities.
It may be depressed by enlargement of the lungs, disease of the heart, or fluid in the pleural or pericardial cavities.
Defn: A thin watery animal fluid, as synovial fluid and pericardial fluid.
Frequently sudden and fatal syncope occurs, due to heart weakness or to the pouring out of fluid into the pleural or the pericardial cavities.
The heart is frequently enlarged, and the pericardial sac contains an excess of serum; the right ventricle, however, is not found disproportionately hypertrophied.
The pericardial cavity contains almost invariably an increased quantity of fluid, which may be so great as to impede the heart's action.
In addition to these hemorrhages there are serous effusions of the muscles similar to those which are found in the pleural and pericardial cavities.
It is true that the limbs may show slight edema in scurvy, and that the pericardial and the pleural sacs, and even the peritoneal cavity, occasionally contain a small quantity of serum, but it is comparatively an insignificant amount.
The bloody exudate in the pericardial cavity indicating pericarditis, which is likely to induce secondary changes of cardiac muscle, may be considered as a possible cause of the increased toxicity of caffein in this case.
Autopsy (dog 31): Lungs congested; heart filled with blood and contained small amount of blood-stained fluid in pericardial sac.
Acute endocarditis can probably not occur without some inyocarditis, and myocarditis probably does not occur without some endocardial disturbance and perhaps some pericardial irritation.
These adhesions between the two surfaces of the pericardium may be general throughout the entire pericardial sac, or they may be limited to some one or more parts of the pericardium.
A diminished alkalinity of the blood would always increase the likelihood of an augmented amount of pericardial or endocardial inflammation.
The treatment, of course, depends largely on the cause of the pericarditis, as, if the cause is one of those just enumerated in which the prognosis is dire, any treatment directed toward the pericardial inflammation is almost useless.
Inflammation of thepericardial sack is usually a secondary disease.
Cattle may suffer from traumatic pericarditis caused by sharp, pointed, foreign bodies passing through the wall of the reticulum and penetrating the pericardial sack.
It is situated in the thoracic cavity between the lungs, and enclosed by a special fold of the pleura, the pericardial sack.
The jagged ends of fractured ribs may cause extensive injury to neighboring parts, and the inflammation spreads to the pericardial sack.
When fluid collects within the pericardial sack, the heart beats become feeble and the pulse weak.
Sharp-pointed objects may penetrate the surrounding tissues or such organs as the spleen, diaphragm, and pericardial sack.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "pericardial" in a variety of sentences. We hope that you will now be able to make sentences using this word.
