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Over 100 perfluorinated organic substances (PFS) oxygen solvents and 80 surfactants have been tested in emulsions for possible use as artificial blood. Most PFS are too toxic, will not form stable emulsions, have too high a vapor pressure, or become firmly attached to the liver, where they are found in both Kupffer cells and hepatocytes. The most promising emulsifiers are Pluronic F68 and Vitrum egg phospholipid. Perfluoromethyldecalin, perfluorodecalin, and perfluorodimethyladamantane are cyclic PFS which are nontoxic oxygen solvents and which are only temporarily retained in the liver. Most straight chain fluorocarbons (C10 or less)—either completely fluorinated or containing terminal hydrogens, bromine, or iodine—are found to leave the liver within periods of 2 wk to several months. Physiologically useful water soluble PFS are reported here for the first time. Although animals survive in apparent health for years with large amounts of certain PFS in the liver and spleen, such linkage indicates a definite reaction with tissue. Therefore, it seems better to avoid using these compounds for organ perfusion and as clinical blood substitutes. We show by extensive morphological examination by light and electron microscopy, that perfluorodecalins produce no changes in the ultrastructure of the liver. PFS that leave the liver and also contain iodine or bromine atoms are radiopaque oxygen solvents useful as diagnostic agents and in microvascular research under various physiological conditions.

Solubility of gases, especially oxygen, in fluorocarbons has achieved important status because of the latter's probable utility in artificial blood and liquid breathing, but only diverse data determined by various methods is scattered throughout the literature and company technical reports. One method, gas chromatography, was used to calculate and compare the oxygen and air solubility of a large number of fluorocarbons. Correlations were made between the oxygen solubilities and some of the physical properties of the compounds. Likewise, solubilities calculated using some lower parachor values resulted in a fairly good correlation.

Fluorocarbons (fluorinated organic compounds in which O2 and CO2 are highly soluble) have been shown to be effective substitutes for the gas transport functions of blood. In order to investigate the effects of fluorocarbons on acute regional myocardial ischemia, we compared the rise of intramyocardial pCO2 (ΔPm CO2) and the decline in intramyocardial pO2 (nadir PmO2) produced by paired, temporary coronary artery occlusions (CAO) in anesthetized dogs instrumented with mass spectrometer probes positioned in ischemic myocardium. In protocol A (n = 7) dogs were ventilated with 100% O2 alone during the first CAO and received fluorocarbons (perfluorochemicals, PFC) 40 ml/kg intravenously in addition to O2 before a second CAO: ΔPmCO2 fell from 32.8 ± 4.7 to 23.3 ± 3.9 mm Hg (p < 0.05) and the nadir PmO2 was higher during the second CAO (21.6 ± 7.4 mm Hg) than during the first (9.4 ± 3.9 mm Hg, p < 0.05). In six dogs in protocol B also ventilated with 100% O2, 40 ml/kg normal saline was infused before the second occlusion, but this did not alter the response to CAO. Thus the degree of volume expansion produced by PFCs did not reduce ischemia in dogs ventilated with 100% O2. Subsequent studies were undertaken to determine whether circulating PFCs ameliorated acute ischemic injury in dogs ventilated with ambient air. In eight dogs in protocol C, ΔPmCO2 was decreased after PFC administration; however, nadir PmO2s were not altered by PFC; in seven dogs in protocol D receiving only normal saline between CAOs, there were no differences in myocardial gas tension. There were no changes in myocardial blood flow to the central ischemic zone between CAOs in any experimental group. We conclude that circulating PFCs reduce acute regional myocardial ischemia during ventilation with either 100% O2 or ambient air, and that PFC-O2 treatment augments myocardial O2 availability in the central ischemic zone. The mechanisms by which PFC-O2 and PFC administration reduce ischemic injury are likely multifactorial, combining elements of enhanced O2 supply and decreased myocardial O2 demand.

Summary Plasma alkaline phosphatase is high in infancy, then drops by the second year of life to a plateau which lasts until pubescence. At 9 years of age in girls and 11 years of age in boys a rapid drop occurs, until by the seventeenth year of life adult values are found. The sex difference which begins at pubescence diminishes gradually until the age of 20 but persists into adulthood, in male subjects higher than in female. The plasma alkaline phosphatase activity seems to be closely related to growth rate as indicated by height measurements and to be derived largely from osteoid tissue as indicated by taurocholate inhibition studies.

The excretion of creatine and creatinine in 280 urine samples from 36 subjects during the course of uncomplicated pregnancies has been studied. Creatinine excretion averaged 1.21 Gm. per 24 hours with a standard deviation of 0.19. The average woman excretes 19.1 mg. of creatinine per kilogram of body weight per day, a value which does not increase, and may even drop somewhat, during pregnancy. The average creatine excretion is 0.24 Gm. per day with values starting at 0.15 Gm. per day in the third lunar month, increasing to a peak of 0.33 at the seventh lunar month, and dropping to 0.22 by the tenth month and to about 0.15 by the first month post partum. The excretion of 17-ketosteroids is significantly higher in those women who excrete large amounts of creatinine, while the basal metabolic rate is higher in those women who excrete larger amounts of creatine. No explanation could be found for the high week-to-week variability in creatine excretion.

METHODS FOR DETECTING AND IMAGING A, TEMPERATURE OF AN OBJECT BY NUCLEAR MAGNETIC RESONANCE ABSTRACT OF THE DISCLOSURE A novel and improved method to detect indirectly a temperature of an object employing nuclear magnetic resonance techniques (NMR). The method involves obtaining an NMR spectrum to determine chemical shift, relaxation times, spin-spin coup-lings or quadrupole couplings for an element of a compound having at least one conformational isomer wherein the compound is influenced by a temperature of the object. Uniquely, the present invention may detect temperature in the body of an animal. Further, the present invention discloses a novel method to determine and monitor thermal physiological states in an animal as well as determine and monitor thermal states in an object. Because of the unique and advantageous non-invasive, non-destructive and non-ionizing properties, the present inven-tion may be employed in an object or animal continuously. The preset invention also provides for the thermal imaging, or NMRthermography, by one-, two-, or three-dimensional reconstruction techniques from chemical shift, relaxation times, (e.g., T1 or T2,) spin-spin couplings and quadrupole couplings for an element of a compound having at least one conformational isomer in an object or animal influenced by a temperature in the object or animal. The methods disclosed are applicable to inanimate and animate solids.