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Biomedical subjects

R KOHN

Publications and source records attributed to R KOHN.

36 records · Page 2Linked to original sources

Effect of histamine on ganglionic transmission.

Histamine has been shown to depress transmission through the perfused superior cervical ganglion of the cat when doses of 150 mug. or more were administered. The intensity of the ganglionic block was related to the dose of histamine employed. In one-third of the experiments, a slow contracture of the nictitating membrane occurred after histamine had been injected; the contracture lasted up to 10 min., and subsequent injections of histamine gave rise to progressively smaller responses. The blocking action of histamine was evident in all experiments and was the most prominent feature observed. Histamine in a sub-depressant dose enhanced the action of the competitive blocking agents tetraethylammonium and hexamethonium, and also the depolarizing blocking agents tetramethylammonium and nicotine. The possible physiological rôle of histamine in the autonomic nervous system is discussed.

Animals↗

Some effects of histamine in the normal and Haemophilus pertussis vaccinated rat.

The effects of histamine in the normal and H. pertussis vaccinated rat have been investigated. In the normal animal small doses of histamine (from 1 to 30 mg./kg., i.v.) produced significant, reversible alterations in the blood pressure, electrocardiogram and electroencephalogram. Doses of 100 mg./kg. or more caused bronchoconstriction and doses of 200 mg./kg. or more an effect on the muscular contractions after electrical stimulation of the nerve. Acute histamine intoxication resulted on rapid injection of 500 mg./kg. intravenously; death was probably due to cardiovascular collapse. In the vaccinated rat, a distinction could be made between the immediate and delayed effects of histamine. With a sublethal dose of histamine (5 mg./kg.) alterations in the blood pressure, electrocardiogram and electroencephalogram were noted. The neuromuscular system, which in the normal animal was the least reactive to histamine, showed the most marked increase in sensitivity in the vaccinated rat. The delayed effects of histamine observed after an interval of 5 to 30 min. were characteristic and irreversible, leading to death of the animal. The mechanism of death in the vaccinated rat after histamine appears to differ from that of the normal animal and has been discussed in the light of present knowledge.

Animals↗

Securing wide appreciation of health statistics.

All the authors are agreed on the need for a certain publicizing of health statistics, but do Amaral Pyrrait points out that the medical profession prefers to convince itself rather than to be convinced. While there is great utility in articles and reviews in the professional press (especially for paramedical personnel) Aubenque, de Groot, and Kohn show how appreciation can effectively be secured by making statistics more easily understandable to the non-expert by, for instance, including readable commentaries in official publications, simplifying charts and tables, and preparing simple manuals on statistical methods. Aubenque and Kohn also stress the importance of linking health statistics to other economic and social information. Benjamin suggests that the principles of market research could to advantage be applied to health statistics to determine the precise needs of the "consumers". At the same time, Aubenque points out that the value of the ultimate results must be clear to those who provide the data; for this, Kohn suggests that the enumerators must know exactly what is wanted and why.There is general agreement that some explanation of statistical methods and their uses should be given in the curricula of medical schools and that lectures and postgraduate courses should be arranged for practising physicians.

Humans↗