Volume 1

A text-book of human physiology : including histology and microscopical anatomy with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition with additions by William Stirling.

Landois, L. (Leonard), 1837-1902. Lehrbuch der Physiologie des Menschen. English

Date:: 1891

Credit: A text-book of human physiology : including histology and microscopical anatomy with special reference to the requirements of practical medicine / by L. Landois ; translated from the seventh German edition with additions by William Stirling. Source: Wellcome Collection.

545/602 page 505

$grape-sugar (more in fever). About |- of these substances seems to be compounds of giycuronic acid (§ 275), and J is due to uric acid and kreatinin (Fliickiger). Aceton (CgHgO) is formed when uoi-mal urine is oxidised with potassic bichromate and sul- phuric acid, and it is formed from a reducing substance present in normal urine (apparently derived from the grape-sugar of the blood). Aceton occurs in traces as a normal urinary con- stituent, which is increased during increased metabolism of the tissues, e.g., carcinoma, in- anition. It has also been found in the blood in fever {v. Jaksch). Lieben's Test.—Acidulate half a litre of urine with HCl and distil; Avhen treated with tincture of iodine and ammonia there is a turbidity due to iodoform (p. 517). II. THE INORGANIC CONSTITUENTS OF THE URINE.—The inorganic constituents are eitlier taken into the body as sucli with the food and pass ofi un- changed in tlie urine, or they are formed in the body, owing to the sulphur and ]3hosphorus of the food being oxidised and the products uniting with bases to form salts. The quantity of salts excreted daily in the urine is 9 to 25 grams [| to f oz.], Sodic chloride—to the amount of 12 (10 to 13) grams [180 grains]—is excreted daily. It is increased, after a meal, by muscular exercise, drinking of water, and generally, when the quantity of urine is increased, by the free use of large quantities of common salt, and by potash salts also; it is diminished under the opposite conditions. In disease it is greatly diminished ; in pneumonia and other inflammations accompanied by effusions, in continued diarrhoea and profuse sweating, constantly in albuminuria and in dropsies. [In cases of pneumonia, sodic cldoride may at a certain stage almost disappear from the urine :—e.g., to 1 or 2 grams—at the crisis 8 grams, and the day after 16 grams— and it is a good sign when the chlorides begin to reappear.] In other chronic diseases, the amount of NaCl excreted runs nearly parallel wdth the amount of urine passed. In condi- tions of excitement the amount of sodic chloride is diminished, and potassic chloride increased ; in conditions of depression the reverse is the case [Zeulzer). Tests for chlorides.—Add to the urine nitric acid and then nitrate of silver solution, which gives a white curdy precipitate of chloride of silver. In albuminous urine the albumin must first be removed. Microscopically look for the step-like forms of common salt, and also for the crystals of sodic chloride and urea (§ 256, 4). [Estimation of Chlorides (Volhard's method).—(1) A S.S. \i.e., a standard solution) of silver nitrate is prepared so that 1 c.c. = -010 grm. ^s^'aCl or -006 of CI. It is placed in a burette. (2) A 10 per cent, solution of neutral Chromate of potash is used as the indicator. Place 2 c.c. of urine in a glass, add a few drops of (2), and drop in (1) from a burette = a red precipitate of Chromate of silver, which disappears on shaking, giving place to a white precipitate of silver chloride. Add S.S. until the fluid in daylight retains a red colour, not orange, i.e., until all the chlorine has been precipitated, v/hich is indicated by the persistence of the red colour of the Chromate of silver. Read off the number of c.c. of the S.S. used. Multiply the number of c.c. of urine passed by the number of c.c. of S.S. used and divide by 200. Suppose a person passed 2000 c.c. of urine in 24 hours and 2 c.c. of the S.S. were required to obtain 9AAA y. 9 the reaction, then -^^^ ^ ^ = 20 grams of NaCl. 200 ^ Mohr's Method.—This simple method gives approximate results. Dilute 10 c.c. of urine with water to 100 c.c; neutralise with carbonate of soda, add 3 drops of a concentrated solution of potassic Chromate. Drop in from a burette a S.S. of silver nitrate (14-53 grms. to 500 c.c. water), until on stirring a red colour persists. Every c.c, of the S.S. = 10 milligrams of ISTaCl or '00607 grams of chlorine. 2. Phosphoric acid occurs in urine [in the form of two classes of phosphates,— (1) Alkaline phosphates as acid sodic phosphate, acid potassic phosphate, and (2) Earthy phosphates,—acid calcic and magnesic phosphates to the amount of about 2 grams daily [30 grains] ; it is more abundant after an animal than after a vegetable diet. The amount increases after a mid-day meal until evening, and falls during the night until next day at noon. It is partly derived from the alka- line and eartliy phosphates of the food, and partly as a decomposition-product of lecithin and nuclein. As phosphorus is an important constituent of the nervous$