Imagens das páginas
PDF
ePub

of proceeding is to mix dried blood in as compact a form as possible with dry, crystallized, powdered common salt, and then to add to this mixture glacial acetic acid, and evaporate at a boiling heat. When this has been done, crystals of hæmine are found where the blood-corpuscles or the substance previously lay, in which the presence of hæmatine was doubtful. This is a reaction which must be ranked among the most certain and reliable ones with which we are acquainted. are acquainted. There is no other substance in which we know such a transformation to take place, but hæmatine. This test is extremely important, because it is applicable in the case of extremely minute quantities, only they must not be spread over too large a surface. It would therefore not be easy of application in a case where we had to deal with a cloth which had been dipped into a thin, watery, fluid coloured with blood. Yet I was able, in the case of a murdered man, on the sleeve of whose coat blood had spurted, and where some of the drops were only a line in diameter, from these minute specks to produce innumerable crystals of hæmine, though of course microscopical ones. In cases in which the ordinary chemical tests would necessarily absolutely fail on account of the smallness of the quantity, we are still able to obtain hæmine. When the mass of blood is so very small, the size of the crystals is certainly also extremely minute, and we then find, as in the case of hæmatoidine, small needles of an intensely brown colour and provided with acute angles.

The third substance which belongs to this series, is the so-called Hæmato-crystalline, a substance about the discovery of which the learned still dispute, for the simple reason that it was found out piecemeal. The first observation concerning it was made by Reichert in extravasations in the uterus of the guinea-pig, in a preparation which, I think, had already lain for some little time in spirits. This

HÆMATO-CRYSTALLINE.

147

observation of his acquired especial significance because he shewed that these crystals in certain respects behaved like organic substances, inasmuch as they became larger through the action of certain agencies, and smaller through that of others, without any change of form, a phenomenon which, up to that time, had not been known to take place in crystals. Afterwards these crystals were again discovered by Kölliker, but Funke, Kunde, and especially Lehmann, have examined them more closely. The result has been that they are very different in different classes of animals, but hitherto it has not been possible to discover any definite reason for their existence, or to obtain any insight into the nature of the substance itself. In man the crystals are tolerably large. At first it was believed that they only occurred in the blood of certain organs, but it has since turned out that they occur everywhere, though they are obtained with greater readiness in certain morbid conditions. In a few very rare cases it happens that they are found already formed in the blood of the dead bodies of animals. These crystals are very easily destructible; both when they dry up and when they become moist, or are brought into contact with any fluid medium, they perish, and they are therefore only observed in certain transitional stages, which must be exactly hit upon, in the destruction of bloodcorpuscles. The well-developed forms in man are perfectly rectangular bodies; but very frequently they are extremely small, and nothing is seen but simple spicules which shoot up into the object at certain spots in large masses. There is besides this peculiarity about them, that they retain the property which hæmatine itself has of becoming bright red with oxygen and dark red with carbonic acid. It is still, however, a frequent subject of discussion whether their whole substance is composed of colouring matter, or whether in this case also the crystals are really colourless and merely impregnated with pigment; this much, however, may

be regarded as certain, that the colour has something very characteristic about it, and that the existence of a close connection between it and the ordinary colouring matter of the blood cannot be doubted.

As

If we now revert to the natural morphological elements of the blood, we meet with the colourless corpuscles as its third constituent. They are present in comparatively small quantity in the blood of a healthy man. To three hundred red corpuscles we reckon about one colourless one. they generally present themselves in the blood, they are spherical corpuscles, which are sometimes a little larger, sometimes a little smaller than, or of the same size as, ordinary red blood-corpuscles, from which they are however strikingly distinguished by the want of all colour and by their perfectly spherical form.

O

FIG. 56.

In a drop of blood which has become quiet, the red corpuscles are usually found aggregated in rows, presenting the familiar form of rouleaux of money, with their flat discs one against the other (Fig. 52, d); in the interspaces may be observed here and there one of these pale, spherical bodies, in which in the first instance, when the blood is quite fresh, nothing more can be distinguished than an occasionally slightly granular looking surface. If water be added, the colourless corpuscles are seen to swell up, and in proportion as they absorb the water, a membrane first becomes distinct; then granular contents gradually come

Fig. 56. Colourless blood-corpuscles from a vein of the pia-mater of a lunatic. 4. Examined when fresh; a in their natural fluid, b in water. B. After the addition of acetic acid: a-c, cells with a single, granular nucleus, which becomes progressively larger, and is finally provided with a nucleolus. d. Simple division of the nuclei. e. A more advanced stage of the division. f-h. Gradual division of the nuclei into three parts. i-k. Four and more nuclei. 280 diameters.

COLOURLESS BLOOD-CORPUSCLES.

149

to view with more and more clearness, and at last some indication is perceived of the presence of one or several nuclei. The apparently homogeneous globule is gradually transformed into a structure with delicate walls, and often so fragile, that when water is incautiously added, the external parts begin to fall to pieces, and in the interior a somewhat granular mass displays itself, which becomes looser and looser, and discloses within it a nucleus generally in process of division, or several nuclei. These may be made to display themselves with much greater rapidity, by treating the object with acetic acid, which renders the membrane translucent, dissolves the nebulous contents, and causes the nucleus to coagulate and shrivel up. The nuclei then are seen to be dark bodies with sharply defined outlines, and one or more in number according to circumstances. In short, we obtain in this way in the majority of cases the view of an object which presents the peculiar appearance that one of our confrères now present, Dr. Güterbock, first proclaimed to be the special characteristic of pus-corpuscles. The question concerning the resemblance or want of resemblance between the colourless cells of the blood and pus-corpuscles still continues to occupy the attention of observers, and it will probably still require a number of years before the views entertained with regard to the connection between the colourless corpuscles and pyæmia have been rendered so clear, that relapses on one side or the other will not now and then recur. There is namely this source of error, that upon examining a number of persons, in the blood of several among them corpuscles will be found which have only a single nucleus, and that a very large one and not unfrequently provided with a nucleolus, whilst in the blood of others no corpuscles will be seen which do not contain several nuclei. Now, since these latter bear a great resemblance to pus-corpuscles, those observers, who had previously chanced to meet with

nothing but uni-nuclear corpuscles in normal blood, cannot be blamed for believing, in another case in which they see multi-nuclear ones, that they have something essentially different before them, namely, pus-corpuscles in the blood, and that the case is one of pyæmia. But, strange to say, the corpuscles with one nucleus form the exception, and you may look for a long time without finding blood in which all the cells have only one nucleus. Oddly enough to-day, whilst occupied in preparing the microscopical objects, I stumbled upon a specimen of blood, in which scarcely

FIG. 57.

anything but cells with one nucleus are to be met with, and these in extremely large number; it was taken from a man who died of smallpox, and in whom a very highly remarkable acute hyperplasia of the bronchial

glands existed.

Now one might be inclined to believe that these are different qualities of blood. But in opposition to such an idea it must be remarked, that, although in the cases in which the one or the other kind of corpuscles exists in large quantities, we have to deal with a pathological phenomenon, yet that, when we do not find such large quantities, we have before us only an earlier or a later stage of the development of the elements. For one and the same blood-corpuscle may, in the course of its life, have one or several nuclei, the one belonging to an earlier, the several to a later, stage of its existence. You must always bear in mind, that the change is seen to take place in the same individual in a short time, indeed often in the course of a few hours, so that in blood which had previously only contained one sort, afterwards quite a different one may

Fig. 57. Colourless blood-corpuscles in variolous leucocytosis. a. Free or naked nuclei. b, b. Colourless cells with small, simple nuclei. c. Larger, colourless cells, with large nuclei and nucleoli. 300 diameters.

« AnteriorContinuar »