William H. Copeland

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Highly purified human lactate dehydrogenase 1 has been used in an interlaboratory evaluation and improvement progran in clinical chemistry in New York State since 1971. Although there are difficulties in determining and assigning the most nearly accurate values for test samples in the absence of a reference method and a reference material, we have minimized(More)
We examined the effects of temperature on the activity and steady-state kinetic properties of alkaline phosphatase (EC 3.1.3.1). Purified isoenzymes from human liver, intestine, and placenta were used, as was human serum, and the enzyme from porcine kidney. Phosphatase activity was estimated by two different assay techniques. For all isoenzymes, apparent(More)
Determination of acid phosphatase activity in clinical laboratories in New York State was evaluated. After the target values were established by 12 reference laboratories, sets of test samples were mailed over a two-year period on three occasions to, respectively, 264, 242, and 239 laboratories. Their initial (1968) results revealed problems: definition of(More)
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