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T P Whitehead

Publications and source records attributed to T P Whitehead.

10 recordsLinked to original sources

The effect of menopausal status and sequential mestranol and norethisterone on serum cholesterol, triglyceride and electrophoretic lipoprotein patterns.

The serum cholesterol, triglycerides and electrophoretic lipoprotein patterns of 35 postmenopausal women, who subsequently received sequential mestranol and norethisterone, were compared with those of 35 premenopasual women of the same age and weight. The postmenopausal women had a significantly higher level of serum cholesterol (p less than 0.01) than the premenopausal women, and a significant reduction (p less than 0.001) occurred in this group after two months of therapy. There was no significant difference in level of serum cholesterol between the premenopausal group and the postmenopausal group receiving sequential mestranol and norethisterone for two months. The serum triglycerides were not significantly higher in the postmenopausal group but there was a significant increase (p less than 0.001) after two months of therapy. The marked alteration in lipid levels at the menopause may in part account for the great increase in coronary artery disease in postmenopausal women but whether these changes are reversible by giving hormone therapy remains speculative.

Adult

An interlaboratory survey of hydrogen ion and blood gas determinations.

A survey of [H+], Pco2, and Po2 analyses in 360 laboratories was conducted using three commercial control materials: two aqueous gas-equilibrated buffer solutions (General Diagnostics and IL) and one whole blood material (DADE). There was little difference in precision or accuracy between instruments, classified according to manufacturer into four groups, and materials for [H+] and Pco2, or in precision for Po2. There were, however, differences in accuracy between instrument groups for Po2 analysis on the aqueous materials, and in some cases the mean values lay outside the range assigned by the material manufacturers. The 35 instruments outside clinical chemistry departments yielded results similar to those of all participants. The relation between inter- and intra-laboratory precision was similar to that for many analytes, suggesting that neither these materials nor the state of these analyses is unsatisfactory. Aqueous materials should, however, be used with caution as accuracy controls for Po2.

Blood

Alkaline phosphatase activity in lyophilised quality control serum.

The rise in alkaline phosphatase activity has been studied after reconstitution of 16 commercial preparations of lyophilised quality control material. The effects of storage temperature and analytical method on the rise in activity have also been studied, with a view to producing a reconstitution protocol suitable for recommendation to participants in external quality control surveys. Great differences were found in the magnitude of this rise in activity; these differences can be reduced to negligible levels if the material is mixed for 30 minutes at ambient temperature after reconstitution and then stored for not more than 4 hours at 4 degrees C before assay.

Alkaline Phosphatase

Analytical luminescence: its potential in the clinical laboratory.

The various types of chemiluminescent and bioluminescent reactions are described. Applications of luminescence in the analysis of substancs of clinical interest are surveyed. The advantages, disadvantages, and prospects for luminescent assays are discussed.

Adenosine Triphosphate

Biochemical and haematological markers of alcohol intake.

The serum gamma-glutamyl-transpeptidase (gamma-G.T.), aspartate transaminase (A.T.), urate, and triglyceride levels and the mean cell volume were estimated in 2034 healthy men. In 14.9% gamma-G.T. was elevated, in 8.0% A.T. was raised, and in 4.2% both enzymes were elevated. Findings were almost identical in a subgroup of 146 whose alcohol intake was known. Both enzymes, serum-urate, and mean cell volume showed a progressive rise with increasing alcohol consumption. The sensitivity of these markers is such that elevated levels are present in those whose alcohol intake would be regarded as normal and who are in no sense alcohol-dependent.

Adult