| PMA | index of prevalence and severity of gingivitis, where P = papillary gingiva, M = marginal gingiva, a... |
|---|---|
| PMD | Pelizaeus-Merzbacher disease; posterior mandibular depth; primary myocardial disease; private medici... |
| PMR | patient meta-record; perinatal mortality rate; periodic medical review; physical medicine and rehabi... |
| PPMA | progressive postmyelitis muscular atrophy |
| PSMA | proximal spinal muscular atrophy |
| Henle's layer | The outer layer cells of the inner root sheath of the hair follicle. (05 Mar 2000) |
|---|---|
| Henle's nervous layer | The layers of the retina from the outer plexiform to the nerve fibre layer inclusive. Synonym: Henle's nervous layer. (05 Mar 2000) |
| Sattler's elastic layer | The middle layer of the choroid. (05 Mar 2000) |
| scrape-off layer | <radiobiology> Outer layer of a plasma which is affected (scraped off) by a divertor or limiter. That is, the outer layer of a magnetically confined plasma (ca. 2 cm thick) where the field lines penetrate a material surface (limiter or divertor plate) rather than close upon themselves. This region defines the outer limit of the plasma because any plasma crossing into the SOL is rapidly lost since transport along the field is much faster than that across the field. That is, particles follow these field lines into the material surface and are lost from the plasma. (09 Oct 1997) |
| horny layer of epidermis | The outer layer of the epidermis, consisting of several layers of flat keratinised non-nucleated cells. Synonym: corneal layer of epidermis, horny layer of epidermis. (05 Mar 2000) |
| horny layer of nail | The outer, horny layer of the nail. Synonym: cornified layer of nail, horny layer of nail. (05 Mar 2000) |
| Purkinje's layer | The layer of Purkinje cells between the molecular and granular layers of the cerebellar cortex. Synonym: stratum neuronorum piriformium, ganglionic layer of cerebellar cortex, layer of piriform neurons, Purkinje's layer, stratum gangliosum cerebelli. (05 Mar 2000) |
| pyramidal cell layer | Layer 3 of the cortex cerebri. Synonym: Meynert's layer. (05 Mar 2000) |
| serous layer of peritoneum | Simple squamous epithelium that forms the glistening surface of the parietal and visceral layers of peritoneum. Synonym: tunica serosa peritonei. (05 Mar 2000) |
| Huxley's layer | A layer of cells interposed between Henle's layer and the cuticle of the inner root sheath of the hair follicle. Synonym: Huxley's membrane, Huxley's sheath. (05 Mar 2000) |
| S layer | <biology> A continuous layer of glycoprotein or protein repeating units forming usually the outermost layer of several species of archae and eu bacteria. About 10 nm thick. (18 Nov 1997) |
| slime layer | <biology, microbiology> A diffused layer of polysaccharide exterior to the bacterial cell wall. Compare: capsule and glycocalyx. (09 Oct 1997) |
| sluggish layer | The layer of the bloodstream in the capillary vessels, next to the wall of the vessel, that flows slowly and transports the white blood cells along the layer wall, while in the centre the flow is rapid and transports the red blood cells. Synonym: plasma layer, Poiseuille's space, sluggish layer. (05 Mar 2000) |
| smear layer | Adherent debris produced when cutting the enamel or dentin in cavity preparation. It is about 1 micron thick and its composition reflects the underlying dentin, although different quantities and qualities of smear layer can be produced by the various instrumentation techniques. Its function is presumed to be protective, as it lowers dentin permeability. However, it masks the underlying dentin and interferes with attempts to bond dental material to the dentin. (12 Dec 1998) |
| somatic layer | The external layer of the lateral mesoderm of the embryo, lying adjacent to the ectoderm and together with it constituting the somatopleure. (05 Mar 2000) |