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Dataset Shift in Clinical Trials This letter outlines how to identify, and potentially mitigate, common sources of “dataset shift” in machine-learning systems. This occurs when the model “training ...

SummaryRadiosensitive tissues show a variety of alterations in radiosodium concentration after total body irradiation above an LD50. In several tissues there is a decrease followed by a sharp increase; the decrease occurs at the same time as a decrease in radiopotassium concentration. An increase in percentage water content may occur when there is a fall in radiosodium concentration. Percent loss of dry weight per day is in general most pronounced in radiosensitive tissues. Urinary excretion of radiosodium after total body irradiation at levels approximating an LD50 shows a complementary homeostatic decrease in response to the excessive loss of radiosodium through the gastrointestinal tract.

SummaryIt has been observed that the reproductive mechanism of A. fischerii is more sensitive to x-irradiation at all measured dosage levels than is the luminescent system of this organism. These findings indicate that cells sterilized by x-irradiation are capable of metabolic activity for a measurable length of time after exposure.

Electric rays, or torpedo fish, inhabit all the temperate and warm waters of the world. The literature of ancient Greece and Rome abounds with references to the strange power of the torpedoes encountered in the Mediterranean Sea. In fact, our word "torpedo" is simply an inherited Latin name that was given the fish because it struck its enemies with a numbness: torpor. Cicero once remarked, Tutantur se . . . torpore torpedines "Torpedoes protect themselves with torpor."' Some centuries earlier Plato had humorously compared the appearance of the philosopher Socrates and his ability to confound opponents with the torpedo and its numbing effect.2 And one found a melange of scientific fact and traditional fiction in the works of the ancient authorities: Aristotle, Pliny the Elder, and Galen. Such was the heritage of naturalists through the Middle Ages and down to the sixteenth and seventeenth centuries. When savants or scientists referred to the torpedo, they had in mind the species known from the Mediterranean Sea, one of which (Torpedo narce) had been elegantly illustrated by Pietro Mattioli in 1598 (see Fig. 1).3 During the years 1684 to 1688 Engelbert Kaempfer, a physician and scholar, was traveling through Persia and reporting his cultural and scientific discoveries. While at the port of Gamron (Bandar Abbas), Kaempfer had an opportunity to study at first hand the varieties of fish caught in the Persian Gulf. His attention was caught by a species of torpedo which, while it resembled the Mediterranean torpedo, differed anatomically and with respect to its faculties as they had been reported by ancient and more recent authors. The Mediterranean torpedo, called Torpedo marmorata Risso, is in fact a diferent species from the Persian Gulf torpedo. Kaempfer is thought to have described Torpedo Sinus

This article presents a comprehensive review of the clinical phenomenon of acupuncture. The historial development of this technique, in China, in other parts of Asia, and in the West is discussed. Contemporary advances in acupuncture applications, such as anesthesia and in the treatment of drug addiction are reviewed. Up-to-date material regarding current physiological theories of acupuncture's mechanism is included. Acupuncture is seen as presenting of challenge to the scientific community which is moving from a posture of scron to justifiable interest.

During the past four years we have evaluated a preceptor program which has been required for all medical students at the University of Wisconsin since 1925. Opinions of alumni and students on a variety of items, a historical note, and restatement of the objectives and methods of the program based, in part, on our studies are included in this report. History A preceptor is traditionally envisaged as a physician who gives a highly personal training to an undergraduate medical student. The usual picture of a preceptor is that of a general practitioner in a rural setting with a student accompanying him in his manifold medical activities. In earlier days the terms preceptorship and apprenticeship were used interchangeably to describe the predominant system of medical education in the United States. From the founding of the colonies until the establishment of the first department of medicine at Philadelphia in 1765, medical schools

The terms atomic energy, radiation and radioactivity all refer to the particles and electromagnetic radiations which are liberated from the nucleus of the atom as a natural phenomenon or by artificial processes. In the explosion of an atomic bomb, vast numbers of such particles and rays are released from the atoms of plutonium or uranium. Several of these penetrate the body with ease and cause injury to the cells that lie in or near their path. The purpose of this report is to restate the changes that are known to occur in the body as the result of exposure to large amounts of such penetrating atomic energy and to emphasize the fact that the resultant signs and symptoms are sufficiently unique and recognizable to warrant the inclusion in the nosology of every physician of a specific disease entity, the acute radiation syndrome. A knowledge of the new nuclear physics is

Excerpt Ionizing radiation today embraces a variety of atomic particles and electromagnetic waves some of which penetrate the body at will while others, although highly damaging, are effective only...

Since April 1971, the news media have published a number of articles from several American correspondents who, after 20 years of knocking at the door, have been granted visas to enter the People's Republic of China. Surgery, medicine, and public health in China have received more attention in these communications than any other subjects.* One reason for the medical emphasis is that in China today one sees a unique program to merge a system of indigenous medicine, which dates back to the dawn of Chinese civilization and has no scientific basis, with modern Western medicine. Diagnosis in traditional Chinese medicine is based primarily on inspection of the patient, study of the tongue, and meticulous palpation of the pulse. The pulse is believed to be divided into segments each of which represents a parenchymatous organ, and the state of an organ is reflected in the rate, strength, and direction of the

The workshop conference on Changing Characteristics of Our Economy and Their Implications in Medical Education first studied the economic trends considered most significant. The standard of living doubles every 25 to 30 years. There has been a leveling process in regard to the financial status of the individual, and the "underprivileged" class is disappearing. As more people have more money, they demand more medical services, more physicians, more paramedical workers, and more hospitals. Increased demand by the consumer is a most significant implication of the changing characteristic of the economy. The steady shift from farm to industry is associated with a sharp increase in income and doubling of per capita income. The state of chronic inflation which we have lived in, and seem destined to continue to live in, raises problems for educational institutions, including teaching hospitals. Educational institutions cannot pass on the increased costs to the consumer as rapidly

The expansion of the atomic energy program and the widespread use of heavy radioactive elements in all areas of research have increased the need for data concerning the permissible total body burden of these elements. Current permissible body burdens are based upon data gathered from several sources. For heavy elements, the information on radium toxicity in man obtained from the luminous dial workers, and from individuals exposed to radium therapeutically or accidentally, serves as a base line (1–4). Permissible total body burdens of other heavy radioactive elements, particularly plutonium, have been arrived at by comparing their toxicity with that of radium in mice or rats and then extrapolating to man on the basis of the radium cases. The toxicity of plutonium has also been studied in a relatively small number of dogs. Thus, the permissible body burden of plutonium has been placed at 0.04 μc, while that for radium is 0.1 μc. Some doubt has arisen as to the reliability of the latter figure, since it has ...

• The four-phase program of postgraduate medical education here described consisted of formal specialized courses at a medical school, informal seminars brought by a team of physicians to rural communities, early-morning open-circuit television programs, and audiovisual seminar kits. The intramural phase was easily evaluated in terms of attendance and direct expressions from the participants. It was one of the two most popular methods, and the most enthusiastic reception was given to courses on heart disease, on medicine in general practice, and on legal implications of medical practice. The three extramural phases were evaluated similarly, the telecast being followed by telephone interviews and mail questionnaires to measure the amount of information actually gained by the medical audience. The results showed that physicians can gain new medical information by these means and that they participate with enthusiasm in programs for continuing medical education.

Excerpt Hyperthyroidism is a disease which may occur during childhood and adolescence. Pemberton and Black1have reported 189 children of 14 years and under who were observed at the Mayo Clinic whil...