In certain pathological conditions an excessive formation and discharge of such material is usually associated with catarrhal changes in the epithelium.
Tsetse-flies are of great economic and pathological importance as the disseminators of tsetse-fly disease (nagana) and sleeping sickness.
In 1861 an alleged "centre" of speech was detected, by a combination of clinical and pathological researches, by Paul Broca (1824-1880).
In England his pathological work won general recognition.
Moreover, we have good reasons for inferring that different constellations of external causes may determine whether the internal physiological disturbances induced by a given agent shall lead to pathological and dangerous variations, or to changes which may be harmless or even advantageous to the plant concerned.
- In many pathological conditions we have degenerative products of various kinds formed in the tissues.
Thus even gout was regarded as a" neurosis."These pathological principles of Cullen are contained in his First Lines of the Practice of Physic, an extremely popular book, often reprinted and translated.
Broussais's system, to which he gave the name of "Medecine physiologique," did much indirect good, in fixing attention upon morbid changes in the organs, and thus led to the rise of the strongly opposed anatomical and pathological school of Corvisart, Laennec and Bayle.
He retired to Darmstadt, where he practised as a physician and contributed regularly to pathological and physiological magazines.
From 1816 he published various papers in the Edinburgh Medical and Surgical Journal, which formed the basis of his Pathological and Practical Researches on Diseases of the Brain and Spinal Cord, and of his Researches on the Diseases of the Intestinal Canal, Liver and other Viscera of the Abdomen, both published in 1828.
The discoveries made in pathological bacteriology, indeed, must be held to be among the most brilliant of the age.
The pathology of aphasia, as worked out by a combination of the experimental, the pathological and the anatomical lines of inquiry is a favourable example of what has been accomplished.
Pathological chemistry has been remarkable chiefly for the knowledge we have obtained of the nature of bacterial poisons.
The use of the term " pathological physiology " may at first appear strange, for if we define physiology as the sum of the normal functions of the body or organism, it may be hard to see how there can be a physiology which is pathological.
According to our present knowledge of physiological and pathological processes, we must regard the cell as the ultimate biological unit - a unit of structure and a unit of function; this was first put forward by Schleiden in 1838, and by Schwann in 1839, but we owe to Virchow the full recognition of the fundamental importance of the living cell in all the processes of life, whether in health or disease.
Some pathological cells, such as the giant-cells of tumours, of bone, and those of tubercle, are polynucleated; in some instances they may contain as many as thirty or more nuclei.
Although the methods of cell-division prevailing in normal structures are maintained generally in those which are pathological, yet certain modifications of these methods are more noticeable in the latter than in the former.
In many pathological cells undergoing indirect segmentation, centrosomes appear to be absent, or at any rate do not manifest themselves at the poles of the achromatic spindle.
In pathological cell-division it happens occasionally that the segmentation of the cytoplasm is delayed beyond that of the mitotic network.
The significance of glycogen in large amounts, or of its absence from the tissues in pathological conditions, is not clearly understood.
Fatty accumulations in the tissues of the body are found in health and in pathological conditions; these are usually recognized and described as fatty infiltrations and fatty degenerations, but there are intermediate conditions which make it difficult to separate sharply these processes.
This splitting up of the fats previously combined with albumin in the cell by the action of natural ferments - lipases - and the setting free of the fats under the influence of toxins represent the normal and the pathological process in the production of so-called fatty degeneration.
Calcification and calcareous deposits are extremely common in many pathological conditions.
This term has been applied to several of the transparent homogeneous appearances found in pathological conditions.
It is now known to have nothing in common with vegetable cellulose, but is regarded as one of the many albuminoid substances existing in the body under pathological conditions.
Skin-grafting and regeneration of bone are among not the least remarkable applications of pathological principles to the combat with disease in recent times; and in this connexion may also be mentioned the daring acts of surgery for the relief of tumours of the brain, rendered practicable by improved methods of localization.
For the special pathological details of various diseases, see the separate articles on Parasitic Diseases; Neuro-Pathology; Digestive Organs; Respiratory System; Blood: Circulation; Metabolic Diseases; Fever; Bladder; Kidneys; Skin Diseases; EYE Diseases; Heart Disease; EAR, &c.; and the articles on different diseases and ailments under the headings of their common names.
375; Wilson, The Cell in Development and Inheritance (London, 1896); Ziegler, " Entztindung," in Eulenburg's Real Encyclopeidie, also Text-Book of Special Pathological Anatomy (Eng.
These are physiology in the modern sense, as dating from Haller, and pathological anatomy, as dating from Morgagni.
In 1872, Hoppe-Seyler (1825-1895) gave a new beginning to our knowledge of the chemistry of secretion and of excretion; and later students have increased the range of physiological and pathological chemistry by investigations not only into the several stages of albuminoid material and the transitions which all foodstuffs undergo in digestion, but even into the structure of protoplasm itself.
If we consult the medical works even of the middle of the 19th century we shall find that, in the light of the present time, accurate knowledge in this sphere, whether clinical, pathological or therapeutical, could scarcely be said to exist.
1843) found an adequate field for the clinical and pathological parts of their work.
Chemical, physiological and pathological research is exploring the secret of these more refined kinds of "anchorage" of molecules.
Milk sugar, lactose, lactobiose, C12H22011, found in the milk of mammals, in the amniotic liquid of cows, and as a pathological secretion, is prepared by evaporating whey and purifying the sugar which separates by crystallization.
Wide as were Virchow's studies, and successful as he was in all, yet the foremost place must be given to his achievements in pathological investigation.
Eventually he was able to prove that the biological doctrine of omnis cellula ecellula applies to pathological processes as well as to those of normal growth, and in his famous book on Cellular-pathologic, published at Berlin in 1858, he established what Lord Lister described as the "true and fertile doctrine that every morbid structure consists of cells which have been derived from pre-existing cells as a progeny."
Every plant is constrained to carry Out its functions of germination, growth, nutrition, reproduction, &c., between certain limits of temperature, and somewhere between the extremes of these limits each function finds ao optimum temperature at which the working of the living machinery is at its best, and, other things being equal, any great departure from this may induce pathological conditions; and many disasters are due to the failure to provide such suitable temperaturese.g.
A plant may be diseased as a whole, because nearly all its tissues are in a morbid or pathological condition, owing to some Fungus pervading the wholee.g.
For instance, the difference between the long-stalked and finely-cut leaves of Anemone attacked with rust and the normal leaves with broad segments, or between the urceolate leaves occasionally found on cabbages and the ordinary formin these cases undoubtedly pathological and teratological respectivelyis nothing like so great as between the upper and lower normalleaves of many Umhelliferae or the submerged and floating leaves of an aquatic Ranunculus or Cabomba.
" Amyloid " occurs as a pathological product, and also in the healthy aorta and in old cartilage.
In the animal kingdom, also, it is very widely distributed, being sometimes a normal and sometimes a pathological constituent of the fluids and tissues; in particular, it is present in large amount in the urine of those suffering from diabetes, and may be present in nearly all the body fluids.
Experimental pathology has benefited by the use of antiseptic surgery in operations upon animals, and by the adoption of exact methods of recording.
The cytology of bone marrow, with the technique of blood examination, is of great assistance in the diagnosis of different pathological conditions.
A system of medicine reared upon anything but a pathological basis would be unworthy of consideration.
The coloured fats, or lipochromes, are found normally in some of the cells of the internal organs, and under certain pathological conditions.
(1888); Pickardt, " Chemistry of Pathological Exudates," Berl.
By his almost exhaustive comparison of febrile movements as symptomatic processes Wunderlich dealt the last blow to the expiring doctrine of the "entity" of "fever"; while on the clinical side Bretonneau and Louis, in 1862-1872, by their careful clinical and pathological studies of forms of fever, relieved the new doctrine of the extravagances of Broussais, and prepared the way for the important distinction of enteric from typhus fever by A.
About the same time, having shown too open sympathy with the revolutionary or reforming tendencies of 1848, he was for; olitical reasons obliged to leave Berlin and retire to the seclusion of Wiirzburg, the medical school of which profited enormously by his labours as professor of pathological anatomy, and secured a wide extension of its reputation.
The same inter-communication prevails between adjacent cells in some animal tissues, and more particularly in those which are pathological, as in the case of the epithelial cells of cancer.
From a pathological point of view the subject of chemiotaxis must be considered along with that of phagocytosis.
Not only so, but the physician, thus fascinated by "types," and impressed by the silent monumentsof the pathological museum, was led to localize disease too much, to isolate the acts of nature, and to forget not only the continuity of the phases which lead up to the exemplary forms, or link them together, but to forget also that even between the types themselves relations of affinity must exist - and these oftentimes none the less intimate for apparent diversities of form, for types of widely different form may be, and indeed often are, more closely allied than types which have more superficial resemblance - and to forget, moreover, how largely negative is the process of abstraction by which types are imagined.
1 Thus they are pro vided with a nucleus which is the centre of cell activity; Pathological both of the reproductive and chemical (metabolic) pro- GelIs.