Publications by authors named "H J Pech"

Historically, it was assumed that reactive, inorganic phosphorus present in pristine environments was solely in the form of orthophosphate. However, this assumption contradicts theories of biogenesis and the observed metabolic behavior of select microorganisms. This paper discusses the role of ion chromatography (IC) in elucidating the oxidation-reduction cycle of environmental phosphorus.

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Little is known about the prebiotic mechanisms that initiated the bioavailability of phosphorus, an element essential to life. A better understanding of phosphorus speciation in modern earth environments representative of early earth may help to elucidate the origins of bioavailable phosphorus. This paper presents the first quantitative measurements of phosphite in a pristine geothermal pool representative of early earth.

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Normal human melanocytes have been shown to respond to the signal peptide endothelin by increased proliferation and melanin formation. Contradictory findings, however, have been reported about which of the two endothelin receptors (EDNRA or EDNRB) is expressed in normal melanocytes and melanoma cells. Moreover it was not clear whether malignant cells differ from their normal precursors in this respect.

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The case history of a 37-year-old woman with the long QT syndrome and drug-refractory paroxysmal ventricular tachyarrhythmias is reported. She was resuscitated eight times between 1980 and 1987. The duration of these attacks increased from a few minutes to 8 hours and the interval between them decreased from 2 years to 4 weeks.

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