PRESERVATIVE 



1178 



PRESTOMIUM 



which presents itself to the examining finger in the 

 center of the plane of the superior strait of the 

 maternal pelvis. P., Abdominal, presentation of 

 the abdomen. P., Arm, prolapse of the arm, usually 

 associated with shoulder-presentation. P., Breast, 

 presentation of the anterior aspect of the child's chest. 

 P., Breech, presentatation of the pelvic extremity of 

 the fetal ellipse. P., Brow, presentation of the brow. 

 P., Cephalic, presentation of any part of the head. 

 P., Cheek, presentation of the cheek. P., Chin, pre- 

 sentation of the chin. P., Coccygeal, breech-presen- 

 tation. P., Complete Foot, presentation of both feet. 

 P., Complicated. Synonym of P., Compound. P., 

 Compound, the presentation of two or more parts at 

 the same time, as the head and hand, etc. P., Ear, 

 presentation of the ear. P., Face, presentation of the 

 face. P., Foot, P., Footling, presentation of one 

 or both feet. P., Frontal. Synonym of P., Face. 

 P., Funis, presentation of the umbilical cord. P., 

 Head, presentation of any part of the head. The 

 vertex-presentation is most common. P., Incomplete 

 Foot, presentation of one foot. P., Knee, presen- 

 tation of one or both knees. P., Longitudinal, the 

 presentation of either the cephalic or the pelvic ex- 

 tremity of the fetal ellipse. P., Mouth, presentation 

 of the mouth. P., Neck, presentation of the neck. 

 P., Occipital, presentation of the occiput. P., 

 Occipito-anterior, a vertex-presentation in which 

 the occiput is anterior. P., Occipito-lateral, pre- 

 sentation of the vertex, with the occiput directed 

 toward one or the other side of the pelvis. P., 

 Occipito-posterior, a vertex-presentation in which 

 the occiput is directed toward the back of the mother's 

 pelvis. P., Occipito-sacral, one in which the occi- 

 put has rotated into the hollow of the sacrum. P., 

 Pelvic, presentation of the pelvic extremity of the 

 fetal ellipse, including breech, foot, and knee presen- 

 tations. P., Placental, placenta prsevia. P., Polar. 

 Synonym of P., Longitudinal. P., Preternatural, 

 a transverse position of the fetus. P., Primary, a 

 presentation that has existed from before the begin- 

 ning of labor. P., Secondary, a presentation that is 

 developed while labor is in progress. P., Shoulder, 

 presentation of the shoulder. P., Side, presentation 

 of the side of the trunk. P., Transverse, one in 

 which the axis of the fetus lies transversely. P., 

 Vertex. See Presentation. 



Preservative ( preser' '-va-tiv ) [ prtzservare, to pre- 

 serve]. Tending to keep from decay. P. Fluid 

 (for section-cuttings of specimens). Many are used. 

 Hamilton recommends equal parts of glycerin and 

 water with about eight minims of carbolic acid to the 

 ounce. One of the best is 80% alcohol. See Stains, 

 Table of. 



Presis [pre' sis) [Kpt/deiv, to burn]. Inflammation ; 

 tumor. 



Presphenoid (presfe' -noid)\_ pre? , before ; o<f>f/v, wedge ; 

 flifof , like]. In human anatomy the anterior part of 

 the body of the sphenoid bone, with its lesser wings. 

 In some of the lower animals it is a separate bone. 



Presphygmic ( presfig'-mifc) [prce, before; ocpvyuoc, 

 pulse]. Pertaining to the period preceding the pulse- 

 wave. 



Prespinal (prespi'-nal) [pro?, before; spina, spine]. 

 In anatomy, ventrad of the spine. 



Presse-artere [pres* '-ar-tar) [Fr.]. An instrument for 

 the compression or temporary occlusion of an artery. 



Pressing [pres'-ing) [ME. ,pressen, to press]. A pas- 

 sive Swedish movement of great service in the treat- 

 ment of nervous affections. 



Pressions (presk'-unz) [ME., pressen, to press]. In 

 massage, exercises in pressing and squeezing the tis- 



sues, either by the ends of the fingers, by the whole 

 hand, or by means of the roulet. 



Pressor (pres'-or) \_premere, to press]. Stimulating. 

 P. Fibers, nerve-fibers, stimulation of which excites 

 the vaso-motor centers, and consequently increases the 

 arterial tension. Others reflexly diminishing the excita- 

 bility of these centers are called Depressor Fibers. 



Pressure (pres/i' ' -ur)\_premere ; to press]. Force, weight, 

 or tension. In massage, a proceeding midway be- 

 tween kneading and percussion. It consists in making 

 firm pressure with a small surface, as the tips of the 

 fingers held stiffly, or the knuckles. It is used espe- 

 cially when it is desired to reach deep-seated nerve- 

 trunks. P., After, the sense of pressure that remains 

 for a brief period after the removal of an object from 

 the surface of the body. P., Arterial, the tension 

 of the blood within the arteries. P., Atmospheric, 

 the pressure of the atmosphere ; it equals about fif- 

 teen pounds to the square inch at sea-level. P.- 

 bandage. See Bandage. P., Blood, the pressure 

 of the blood against the walls of the vessels or of the 

 heart. It is measured by means of the manometer. 

 P., Endocardial, the pressure of the blood within 

 the heart. P. of Inspiration, the pressure of the 

 air in the respiratory organs during the act of inspi- 

 ration. P., Intra-abdominal, the pressure exerted 

 upon the parietes by the abdominal viscera. P., 

 Intra-cranial, the pressure of the contents of the 

 cranium upon its walls. P., Intra-ocular. See 

 Tension, Intraocular. P., Intra-thoracic, the pres- 

 sure of the intra-thoracic organs upon the walls of 

 the chest. P., Negative, the force of suction ; also 

 absence of pressure. P.-phosphenes. See Pies- 

 p/ienes. P. -Points (or Spots), points of marked sen- 

 sibility to pressure or weight, arranged like the tem- 

 perature-spots, and showing a specific end-apparatus 

 arranged in a punctated manner and connected with 

 the pressure-sense. P. -sense, the sense by which 

 pressure upon the surface is appreciated. P. -sore. 

 See Bed-sore. P. -symptoms : 1. Nervous symptoms 

 due to pressure upon the brain or spinal cord. In 

 general, if the pressure is light, the symptoms are those 

 of irritation of the area pressed upon, manifesting 

 themselves as spasmodic movements, tonicity of the 

 muscles, pain, hyperesthesia, etc. ; if the pressure is 

 great, there results paralysis, motor or sensory or 

 both, of the parts innervated by the areas pressed 

 upon. 2. The symptoms produced by an aneurysm 

 or a tumor, as of the pelvis, adjacent organs being 

 . impinged upon. P.-tests, tests made to ascertain 

 the quality or acuteness of the pressure-sense. They 

 may be made by using objects of the same form and 

 size but of different weights. P.-theory, a theory 

 that ascribes the formation of hernia to an overcoming 

 of the resistance of the abdominal parietes at a 

 weakened spot by the intra-abdominal pressure. P., 

 Venous, the blood-pressure in the veins. 



Presternal (prester'-nal) \_prce, before ; sternum, Ac 

 breast-bone]. In biology, of or pertaining to the 

 presternum. 



Presternalis (prester-na'-Iis) [prtr, before ; sternum, 

 sternum]. A muscle passing along one or both sides 

 of the sternum, from above downward to the fourth 

 or fifth rib, or lower. 



Presternum (pre-ster'-nt/m) [ pra, before ; sternum, I 

 the breast-bone]. In biology, the manubrium or 

 cephalic segment of the sternum. 



Prestomial { presto' -me-al) [pr<?, before; ordpa, | 

 mouth]. Extending beyond or in front of the mouth. 



Prestomium (presto' -me-um) [pr<e, before; ffi 

 mouth]. In biology, a distinct cephalic segment of 

 the higher polychetous worms. 



