(n.) One of a class of cellular, flowerless plants, (technically called Lichenes), having no distinction of leaf and stem, usually of scaly, expanded, frond-like forms, but sometimes erect or pendulous and variously branched. They derive their nourishment from the air, and generate by means of spores. The species are very widely distributed, and form irregular spots or patches, usually of a greenish or yellowish color, upon rocks, trees, and various bodies, to which they adhere with great tenacity. They are often improperly called rock moss or tree moss.
(n.) A name given to several varieties of skin disease, esp. to one characterized by the eruption of small, conical or flat, reddish pimples, which, if unchecked, tend to spread and produce great and even fatal exhaustion.
Example Sentences:
(1) The vulvar white keratotic lesions which have been subjected to histological examination in Himeji National Hospital (1973-1987) included 13 cases in benign dermatoses, 4 cases in vulvar epithelial hyperplasia, 3 cases in lichen sclerosus, and 3 cases in lichen sclerosus with foci of epithelial hyperplasia.
(2) The counts of EAC-receptor carrying neutrophils were two times lower in the patients with erosive ulcerative lichen planus as against those with the typical form of the disease.
(3) The abundance of adhesion molecules on leukocytes and keratinocytes in oral lichen planus is indicative of a special state of activation.
(4) The cases were all consecutive patients with a new diagnosis of lichen planus, and the controls were patients under dermatological care observed under the same conditions.
(5) The purpose of this investigation was to specifically identify T cells, B cells, and histiocytes in the infiltrate typically seen in lichen planus.
(6) In an ultrastructural study of oral lesions in lichen planus, it was found that some plasma cells have an associated lamina densa.
(7) Oral lichen planus is a chronic inflammatory disease of adult onset.
(8) Eighteen lichens from a variety of habitats were treated with 4-chlorobiphenyl (4-CB).
(9) In lichen planus, the cells appeared more dendritic and equal numbers of CD1, HLADR, HLADP and HLADQ positive cells were found, with significantly more HLADP (P less than 0.01) and HLADQ (P less than 0.05) positive cells than in normal mucosa.
(10) In a 45-year-old patient with an unusual clinical course of wide-spread cutaneous and oral lichen planus as well as pemphigus vulgaris of the oral cavity, both refractory to standard therapy, a Castleman tumour was suspected.
(11) A case of Lichen aureus in a 15-year old boy is presented.
(12) Specifically, we were able to make a diagnosis of psoriasis in four cases, lichen planus in three cases, and Darier's disease in one case.
(13) Lichen planus is a common disorder of unknown aetiology.
(14) The result of topical treatment by dimethyl sulphoxide (DMSO) in a patient with lichen amyloidosus is reported.
(15) Additionally, a lichenoid inflammatory infiltrate is seen at the periphery of the verrucous lesions, and in one case this has the pattern of classic lichen sclerosus.
(16) This feature can be found in several dermatoses and particularly in lichen striatus and acantholytic linear naevus.
(17) The relative incidence of this condition, compared with the incidence of all forms of lichen planus, was smaller than that reported in the literature.
(18) In lichen planus, an increase both in the number of Langerhans cells and the numbers expressing CD4 were found in areas of keratinocyte HLADR expression compared with HLADR negative areas and with normal oral mucosa.
(19) Focal areas of established lichenoid reaction, that are indistinguishable from lichen planus, are common.
(20) The high incidence of familial lichen planus supports the hypothesis that genetic factors are of etiologic importance in lichen planus.
Usnea
Definition:
(n.) A genus of lichens, most of the species of which have long, gray, pendulous, and finely branched fronds. Usnea barbata is the common bearded lichen which grows on branches of trees in northern forests.
Example Sentences:
(1) High activity against Gram+ bacteria has been observed, although Parmelia caperata, Evernia prunastri and Usnea sp.
(2) Products from Fehling and Cetavlon precipitation, the latter at pH 8.5 in the presence of borax, were structurally similar, except with those of Usnea sp., U. meridionalis, Parmotrema araucaria and Evernia prunastri, which were mixtures and initially provided precipitates at pH 7 due to the presence of carboxyl groups.
(3) Parmelia caperata and Parmelia reticulata were positive in all, and in a descending order of positivity: Pseudovernia furfuracea, Evernia prunastri, Usnea spp, Ramalina lusitanica.