| lymphoid interstitial pneumonitis | <pathology> A form of pneumonia which is characterised by diffuse interstitial infiltrates and infiltration of lymphocytes into the lung tissue. (27 Sep 1997) |
|---|---|
| lymphoid leukaemia | <haematology, oncology> An acute form of childhood leukaemia characterised by the development of abnormal cellsdevelop in the bone marrow and lymphoblasts are found in blood-formingtissues. A type of chronic leukaemia found most often in the elderly, it is characterised by the presence of mature lymphocytes in the blood. Origin: Gr. Haima = blood (13 Nov 1997) |
| lymphoid polyp | Benign polyp consisting of aggregates of lymphocytes in the rectum. (05 Mar 2000) |
| lymphoid ring | The broken ring of lymphoid tissue, formed of the lingual, faucial, and pharyngeal tonsils. Synonym: Bickel's ring, tonsillar ring, Waldeyer's throat ring. (05 Mar 2000) |
| lymphoid series | The cells at various states in the development in lymphoid tissue of the mature lymphocytes, e.g., lymphoblasts, young lymphocytes, mature lymphocytes. (05 Mar 2000) |
| lymphoid tissue | <anatomy> Tissue that is particularly rich in lymphocytes (and accessory cells such as macrophages and reticular cells), particularly the lymph nodes, spleen, thymus, Peyer's patches, pharyngeal tonsils, adenoids and (in birds) the Bursa of Fabricius. Central lymphoid tissue: A term occasionally used as synonym for primary lymphoid tissue but should be avoided to prevent confusion between anatomical location, which is irrelevant and centrality in the system. Peripheral lymphoid tissue: Secondary lymphoid tissue, not necessarily located peripherally. Primary lymphoid tissue: Lymphoid tissues in which immune cells develop as opposed to the secondary or peripheral lymphoid tissues in which antigen independent or antigen dependent stages of maturation take place and in which responsive lymphocytes are found. Primary lymphoid tissues are foetal liver, adult bone marrow and thymus (and Bursa of Fabricius in birds). Secondary tissues are lymph nodes, spleen, tonsils and mucosa associated lymphoid tissue. (20 Mar 1998) |
| lymphoidectomy | Excision of lymphoid tissue. Origin: Lymphoid + G. Ektome, excision (05 Mar 2000) |
| lymphoidocyte | A primitive mesenchymal cell believed to be capable of differentiating into all types of lymphoid cells, including lymphocytes, littoral cells, and reticular cells of lymph nodes. (05 Mar 2000) |
| lymphokine | <growth factor> Substance produced by a leucocyte that acts upon another cell. Examples are interleukins, interferon alpha, lymphotoxin (tumour necrosis factor alpha), granulocyte monocyte colony-stimulating factor (GM-CSF). The term is becoming less common and cytokine, a more general term, is taking over. Cytokines include lymphokines. (20 Mar 1998) |
| lymphokines | Soluble protein factors generated by activated lymphocytes that affect other cells, primarily those involved in cellular immunity. (12 Dec 1998) |
| lymphokinesis | 1. Circulation of lymph in the lymphatic vessels and through the lymph nodes. 2. Movement of endolymph in the saemicircular canals of the inner ear. Synonym: lymphocinesis, lymphocinesia. Origin: Lympho-+ G. Kinesis, movement (05 Mar 2000) |
| lympholeukocyte | <haematology> White cell of the blood that are derived from stem cells of the lymphoid series. Two main classes are recognised, T and B lymphocytes, the latter responsible (when activated) for production of antibody, the former subdivided into subsets (helper, suppressor, cytotoxic T-cells) and responsible both for cell-mediated immunity and for stimulating B-cells. (18 Nov 1997) |
| lymphology | Synonym: lymphangiology. Origin: Lympho-+ G. Logos, study (05 Mar 2000) |
| lymphoma | <oncology, tumour> Malignant tumour of lymphoblasts derived from B lymphocytes. most commonly affects children in tropical Africa: both Epstein Barr virus and immunosuppression due to malarial infection are involved. (18 Nov 1997) |
| lymphoma, aids-related | B-cell lymphoid tumours that occur in association with aids. Patients often present with an advanced stage of disease and highly malignant subtypes including burkitt lymphoma, immunoblastic large-cell lymphoma, small non-cleaved-cell lymphoma and diffuse large-cell lymphoma. The tumours are often disseminated in unusual extranodal sites and chromosomal abnormalities are frequently present. It is likely that polyclonal B-cell lymphoproliferation in aids is a complex result of ebv infection, HIV antigenic stimulation, and T-cell-dependent HIV activation. (12 Dec 1998) |