Rheumatoid Nodule: Subcutaneous nodules seen in 20-30% of rheumatoid arthritis patients. They may arise anywhere on the body, but are most frequently found over the bony prominences. The nodules are characterized histologically by dense areas of fibrinoid necrosis with basophilic streaks and granules, surrounded by a palisade of cells, mainly fibroblasts and histiocytes.Rheumatic Nodule: A small round or oval, mostly subcutaneous nodule made up chiefly of a mass of Aschoff bodies and seen in cases of rheumatic fever. It is differentiated from the RHEUMATOID NODULE which appears in rheumatoid arthritis, most frequently over bony prominences. (From Dorland, 27th ed)Neuroma: A tumor made up of nerve cells and nerve fibers. (Dorland, 27th ed)Arthritis, Rheumatoid: A chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. Etiology is unknown, but autoimmune mechanisms have been implicated.Chimerism: The occurrence in an individual of two or more cell populations of different chromosomal constitutions, derived from different individuals. This contrasts with MOSAICISM in which the different cell populations are derived from a single individual.Rheumatoid Factor: Antibodies found in adult RHEUMATOID ARTHRITIS patients that are directed against GAMMA-CHAIN IMMUNOGLOBULINS.Leprosy, Lepromatous: A chronic communicable infection which is a principal or polar form of LEPROSY. This disorder is caused by MYCOBACTERIUM LEPRAE and produces diffuse granulomatous skin lesions in the form of nodules, macules, or papules. The peripheral nerves are involved symmetrically and neural sequelae occur in the advanced stage.Elbow: Region of the body immediately surrounding and including the ELBOW JOINT.Thyroid Gland: A highly vascularized endocrine gland consisting of two lobes joined by a thin band of tissue with one lobe on each side of the TRACHEA. It secretes THYROID HORMONES from the follicular cells and CALCITONIN from the parafollicular cells thereby regulating METABOLISM and CALCIUM level in blood, respectively.Neoplasms, Adnexal and Skin Appendage: Neoplasms composed of sebaceous or sweat gland tissue or tissue of other skin appendages. The concept does not refer to neoplasms located in the sebaceous or sweat glands or in the other skin appendages.Granuloma Annulare: Benign granulomatous disease of unknown etiology characterized by a ring of localized or disseminated papules or nodules on the skin and palisading histiocytes surrounding necrobiotic tissue resulting from altered collagen structures.Metacarpal Bones: The five cylindrical bones of the METACARPUS, articulating with the CARPAL BONES proximally and the PHALANGES OF FINGERS distally.Osteopathic Medicine: A medical discipline that is based on the philosophy that all body systems are interrelated and dependent upon one another for good health. This philosophy, developed in 1874 by Dr. Andrew Taylor Still, recognizes the concept of "wellness" and the importance of treating illness within the context of the whole body. Special attention is placed on the MUSCULOSKELETAL SYSTEM.Achilles Tendon: A fibrous cord that connects the muscles in the back of the calf to the HEEL BONE.Dermatology: A medical specialty concerned with the skin, its structure, functions, diseases, and treatment.Tenosynovitis: Inflammation of the synovial lining of a tendon sheath. Causes include trauma, tendon stress, bacterial disease (gonorrhea, tuberculosis), rheumatic disease, and gout. Common sites are the hand, wrist, shoulder capsule, hip capsule, hamstring muscles, and Achilles tendon. The tendon sheaths become inflamed and painful, and accumulate fluid. Joint mobility is usually reduced.Rheumatic Diseases: Disorders of connective tissue, especially the joints and related structures, characterized by inflammation, degeneration, or metabolic derangement.De Quervain Disease: Stenosing tenosynovitis of the abductor pollicis longus and extensor pollicis brevis tendons in the first dorsal wrist compartment. The presenting symptoms are usually pain and tenderness at the radial styloid. The cause is almost always related to OVERUSE INJURY or is associated with RHEUMATOID ARTHRITIS.Wrist Joint: The joint that is formed by the distal end of the RADIUS, the articular disc of the distal radioulnar joint, and the proximal row of CARPAL BONES; (SCAPHOID BONE; LUNATE BONE; triquetral bone).Habits: Acquired or learned responses which are regularly manifested.ArthritisJoints: Also known as articulations, these are points of connection between the ends of certain separate bones, or where the borders of other bones are juxtaposed.Arthritis, Experimental: ARTHRITIS that is induced in experimental animals. Immunological methods and infectious agents can be used to develop experimental arthritis models. These methods include injections of stimulators of the immune response, such as an adjuvant (ADJUVANTS, IMMUNOLOGIC) or COLLAGEN.Trimethylsilyl Compounds: Organic silicon derivatives used to characterize hydroxysteroids, nucleosides, and related compounds. Trimethylsilyl esters of amino acids are used in peptide synthesis.Inflammation: A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.Pathology, Surgical: A field of anatomical pathology in which living tissue is surgically removed for the purpose of diagnosis and treatment.Privacy: The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)Confidentiality: The privacy of information and its protection against unauthorized disclosure.Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Computer Security: Protective measures against unauthorized access to or interference with computer operating systems, telecommunications, or data structures, especially the modification, deletion, destruction, or release of data in computers. It includes methods of forestalling interference by computer viruses or so-called computer hackers aiming to compromise stored data.Publishing: "The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.Journal Impact Factor: A quantitative measure of the frequency on average with which articles in a journal have been cited in a given period of time.Lymphangioleiomyomatosis: A disease characterized by the progressive invasion of SMOOTH MUSCLE CELLS into the LYMPHATIC VESSELS, and the BLOOD VESSELS. The majority of the cases occur in the LUNGS of women of child-bearing age, eventually blocking the flow of air, blood, and lymph. The common symptom is shortness of breath (DYSPNEA).Solitary Pulmonary Nodule: A single lung lesion that is characterized by a small round mass of tissue, usually less than 1 cm in diameter, and can be detected by chest radiography. A solitary pulmonary nodule can be associated with neoplasm, tuberculosis, cyst, or other anomalies in the lung, the CHEST WALL, or the PLEURA.Pneumothorax: An accumulation of air or gas in the PLEURAL CAVITY, which may occur spontaneously or as a result of trauma or a pathological process. The gas may also be introduced deliberately during PNEUMOTHORAX, ARTIFICIAL.Pleurisy: INFLAMMATION of PLEURA, the lining of the LUNG. When PARIETAL PLEURA is involved, there is pleuritic CHEST PAIN.Diabetes Insipidus: A disease that is characterized by frequent urination, excretion of large amounts of dilute URINE, and excessive THIRST. Etiologies of diabetes insipidus include deficiency of antidiuretic hormone (also known as ADH or VASOPRESSIN) secreted by the NEUROHYPOPHYSIS, impaired KIDNEY response to ADH, and impaired hypothalamic regulation of thirst.Hemoptysis: Expectoration or spitting of blood originating from any part of the RESPIRATORY TRACT, usually from hemorrhage in the lung parenchyma (PULMONARY ALVEOLI) and the BRONCHIAL ARTERIES.Multiple Pulmonary Nodules: A number of small lung lesions characterized by small round masses of 2- to 3-mm in diameter. They are usually detected by chest CT scans (COMPUTED TOMOGRAPHY, X-RAY). Such nodules can be associated with metastases of malignancies inside or outside the lung, benign granulomas, or other lesions.Sleep: A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.Cytokines: Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.Sleep Disorders: Conditions characterized by disturbances of usual sleep patterns or behaviors. Sleep disorders may be divided into three major categories: DYSSOMNIAS (i.e. disorders characterized by insomnia or hypersomnia), PARASOMNIAS (abnormal sleep behaviors), and sleep disorders secondary to medical or psychiatric disorders. (From Thorpy, Sleep Disorders Medicine, 1994, p187)Sleep, REM: A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern EEG. It is usually associated with dreaming.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Gastrointestinal Stromal Tumors: All tumors in the GASTROINTESTINAL TRACT arising from mesenchymal cells (MESODERM) except those of smooth muscle cells (LEIOMYOMA) or Schwann cells (SCHWANNOMA).Metacarpophalangeal Joint: The articulation between a metacarpal bone and a phalanx.Thyroid Function Tests: Blood tests used to evaluate the functioning of the thyroid gland.Finger Joint: The articulation between the head of one phalanx and the base of the one distal to it, in each finger.C-Reactive Protein: A plasma protein that circulates in increased amounts during inflammation and after tissue damage.Antirheumatic Agents: Drugs that are used to treat RHEUMATOID ARTHRITIS.Peptides, Cyclic: Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).Citrulline