Johann Colvin

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A prospective, randomized, controlled trial was conducted in 200 consecutive patients undergoing endoscopy of the upper alimentary tract. One hundred patients received supplementary oxygen at 4 liters/minute through nasal cannulae, while 100 patients received no additional oxygen. Within each of these two groups, 50 patients were sedated with midazolam and(More)
Recently the lateral width of the cellulose microfibril has been estimated as 30 A rather than about 150 to 200 A, by extrapolation of data from model shadowing experiments. The difference was attributed to a layer of metal deposited during shadowing. However, direct photographs of the same microfibrils parallel and perpendicular to the direction of(More)
OBJECTIVE To investigate the concentrations of triglyceride, cholesterol, and high-density lipoprotein during a 50-hr infusion of 2% propofol, starting within 24 hrs of admission to the intensive care unit (ICU). DESIGN Prospective, clinical study. SETTING ICU, university hospital. PATIENTS Thirty adult patients, who were ventilated and expected to be(More)
The structure and composition of the cell walls of hyphae of Neurospora crassa were investigated by electron microscopy, chemical analysis, and X-ray diffraction both before and after progressive enzymatic degradation by snail gut enzymes, chitinase, and trypsin. The wall consists of two phases: randomly disposed skeletal microfibrils of chitin only and an(More)
Arterial hypertension after cardiac surgery is common and is associated with increased morbidity. Glyceryl trinitrate may be a more suitable agent for control of hypertension than sodium nitroprusside. We have developed a closed-loop system for the Atari 1040ST microcomputer to control arterial pressure by the simultaneous infusion of two vasodilators under(More)
A novel C(35) terpene and its monounsaturated analogue were isolated from cultures of Acetobacter xylinum, together with traces of their C(36) homologues. These substances were found to be hopane derivatives substituted by a five-carbon chain bearing four vicinal hydroxyl groups. For the parent hydrocarbon the term bacteriohopane is proposed. The(More)
1. The bacterium Acetobacter xylinum produces extracellular cellulose microfibrils that form a pellicle in the medium enmeshing the bacterial cells. These microfibrils may show some localized alignment, which can be seen as birefringence when the culture is viewed between crossed Polaroid sheets. 2. An increase in birefringence can be induced by the(More)
Methanobacterium bryantii was found to undergo rapid lysis when grown in a prereduced chemically defined medium under H2-CO2 (4:1, vol/vol). The addition of 20 mM MgCl2 to the medium gave, rather than rapid lysis, a gradual formation of phase-dark spherical bodies which in thin section appeared as true protoplasts. In general, the protoplasts were(More)