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66 adjustment, actually favorable to the individual. Experimental pathology has developed along both biological and chemical lines: the former, accentuating the life-history of the abnormal growth, the latter, endeavoring to trace back the changes observed to the chemical activities involved in the life-process. Somewhat recently, a shifting of emphasis has made the physiological point of view more prominent,— a wholesome development, medically speaking. The physician is constantly in contact with disease processes that he is unable to correlate with the accompanying structural modifications. Occasionally the surgeon throws a stream of light upon such a situation; too often, all is dark until the autopsy reveals the truth. Pathological physiology aims to study structural change from the standpoint of function. It asks primarily not what is the history of the structural modification itself, but what are its progressive consequences to the functional routine of the organism. It reproduces disease experimentally, interrupting its course at significant stages, in order, having observed the functional disturbance, to ascertain exactly the structural readjustment that corresponds. "In animals,11 says Professor Hektoen, "the course of disease may be cut short at any time for the purpose of investigation. The disease may be studied in all its phases. Comparative pathology became the refuge of the investigator, blocked by the necessary restrictions governing the study of human diseases. The great influence of the comparative method is shown in the relatively advanced state of our knowledge in regard to human diseases readily communicable to animals, as compared with our ignorance in regard to other human diseases which, so far as we know, are not transferable to animals." For the prospective physician the value of such a course depends, of course, on the opportunity to compare the laboratory findings with the symptoms shown by patients in the hospital wards.

In general, the effective teaching of pathology is dependent on ease and frequency of access to the autopsy-room. It would be difficult just now to over-emphasize that point. We shall soon see that the post-mortem is in this country relatively rare and precarious; that not infrequently pathological courses are organized and given whose illustrative material is limited to models, to a small number of preserved specimens, or even to bits of material already cut into microscopic sections or just lacking that last touch. Such instruction may do justice to the subject on the histological side, but it leaves much to the already overburdened third and fourth years. And it is surely a serious disadvantage to the teacher of pathology to find himself year after year teaching the subject without access to the post-mortem room.

Specimens alone—whether gross or microscopic—are inadequate for several reasons. In the first place, gross fresh specimens are too perishable: they change quickly after removal from the body and inconsequence of handling during transportation; refrigeration avoids softening and putrefaction only at the cost of destroying the blood,—a most important link in the chain. More important still, however, is the consideration that disease is not an affair of a single organ or tissue, still less, of a