kidney

(kid’ne) [L. ren]. Either of the two glandular ies in the lumbar region that secrete the urine. Each kidney is about four inches long, two inches wide, and one inch thick, and weighs from four to six ounces. The kidney is of characteristic shape, presents a notch on the inner border, known as the kilus, which communicates with the cavity or sinus by which the ve els, nerves, and ureter pa . The kidney consists of a cortical substance and of a medullary substance. The medullary substance forms pyramids, whose bases are in the cortex, and whose apices, which are called pa pill, project into the calices of the pelvis of the kidney. The renal pyramids of Malpighi are in three rows, and number from ten to fifteen. The parenchyma of the kidney is composed of uriniferous tubules, held together by a little connective ti ue. The terminal orifices of these open at the summit of each papilla. A uriniferous tubule begins at a capsule of Malpighi within the cortex, has a neck or constriction below the capsule, becomes the proximal convoluted tube, then the spiral tube of Scha- chow a, and succe ively Henle’s loop, irregular tubule, distal convoluted tubule, curved tubule, and the straight collecting tubule, which opens at the apex of a renal papilla. The straight collecting tubes converge as they descend, forming groups in the center, known as medullary rays. The pyramids of Ferrein are the subordinate cones of the kidney papillz. The tubules are lined with pavement epithelium; the epithelium in other portions varies in shape and size. An envelop of a glomerule of the kidney is known as Bowman's capsule. Urine is formed by a proce partly physical and partly vital, the watery elements being extruded from the blood by filtration; the solid portions by a special elaborative action of the renal epithelium. amyloid k., one that is the seat of amyloid or waxy degeneration. arteriosclerotic k., a kidney contracted as a result of sclerosis of the renal arteries. branny k., a kidney which appears as if it contained bran, due to fatty degeneration in spots. cicatricial k., a shriveled, irregular, and scarred kidney: usually the last stage of a surgical kidney. cirrhotic k., granular kidney. contracted k., granular kidney. cyanotic k., pa ive congestion of the kidney. cystic k., a kidney containing cysts. fatty k., a kidney affected with fatty degeneration. floating k., one which is loosened and displaced. Formad’s k., an enlarged and deformed kidney, sometimes seen in_ chronic alcoholism. gouty k., granular k., one affected with chronic interstitial. inflammation. head-k., the pronephros. horseshoe-k., the two kidneys partially united or fused. lardaceous k., an amyloid kidney. large white k., one affected with chronic interstitial nephritis. ma age-k., a condition of chronic renal incompetence and uremia due to exce ive excretory effort on the part of the kidney, resulting from the improper and exce ive application of ma age to a gouty patient. mural k., a kidney located in a pocket of peritoneum in the abdominal wall. palpable k., slight nephroptosis. pelvic k., dislocation of the kidney into the pelvis. pigback k., a kidney congested and enlarged as a result of chronic alcoholism. primordial k., the pronephros. red contracted k., a gouty kidney. Rokitansky’s k., amyloid kidney. Rose-Bradford k., a form of fibrotic kidney of inflammatory origin found in young subjects. sclerotic k., granular kidney. sigmoid K., a deformed and fused kidney somewhat resembling the horseshoe form. small white Κ., an atrophied and degenerated state of the kidney ollowing a chronic interstitial nephritis. soapy K., a large white kidney which contains myelins instead of simple fats. solitary k., a kidney made up of two kidneys fused. succenturiate k., a suprarenal body. supernumerary k., an occasional kidney-like structure detached from the kidney proper. surgical k., suppurative pyelonephritis following an operation upon ἃ urinary organ. wandering K., a floating or displaced kidney. waxy k., an amyloid kidney.