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Biomedical subjects

N M Greene

Publications and source records attributed to N M Greene.

At least 37 records · Page 2Linked to original sources
PubMed1979

3-Methoxy-4-hydroxyphenethyleneglycol production by human brain in vivo.

A direct method has been employed to estimate the rate of production by human brain of 3-methoxy-4-hydroxyphenethyleneglycol, the major metabolite of brain norepinephrine, a brain neurotransmitter. Venous specimens were obtained from the internal jugular vein from ten awake human subjects at a puncture site above the common facial vein, the first major source of extracranial inflow. Arterial specimens were simultaneously obtained from the radial artery. Plasma samples were assayed and a highly significant difference was found in the concentration of the metabolite in plasma coming out of the brain (venous blood) as compared to plasma entering the brain (arterial blood). This venous-arterial difference was calculated to be 0.7 +/- 0.1 nanogram per milliliter of blood. Assuming an adult brain weight of 1400 grams and normal cerebral blood flow, it is estimated that the rate of production of 3-methoxy-4-hydroxyphenethyleneglycol by the awake human brain is approximately 597 nanograms per minute or 35.8 micrograms per hour. Urine specimens were also collected from six of these subjects during a period of 1 to 3.5 hours, which bracketed the time the blood samples were obtained. For these six subjects the output of 3-methyoxy-4-hydroxyphenethyleneglycol by whole brain was estimated to be 40.9 micrograms per hour, whereas the rate of its excretion into urine was 64.5 micrograms per hour.

Adult↗
PubMed1979

Anesthesia and the development of surgery (1846-1896).

The hypothesis that the introduction of anesthesia in 1846 accelerated the development of surgery was tested by compiling statistics on the types of operations performed in this country and abroad in the absence of anesthesia (prior to 1846) and over the 50-year period after 1846. Prior to 1846, surgery involved the extremities and superficial parts of the body almost exclusively. The same was generally true for 50 years following 1846. The introduction of anesthesia was necessary before surgery could advance, but control of infection, establishment of the sciences of pathology and physiology, and development of professionalism in clinical medicine and surgery based on research and teaching were also required. Almost a half-century lapsed after the introduction of anesthesia before surgery advanced significantly beyond the stage it was at prior to the introduction of anesthesia in 1846.

Anesthesiology↗