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D J Woo

Publications and source records attributed to D J Woo.

2 recordsLinked to original sources

Polymeric columns for liquid chromatography.

Polymeric columns are becoming used more frequently in modern liquid chromatography applications as improvements in polymeric packing materials are realized and as more applications are developed for these materials. Modern polymers have overcome earlier problems associated with their use; higher rigidity now allows them to be used at normal eluent flow rates resulting in faster analyses, and improved synthesis techniques have resulted in efficiencies comparable to the best silica materials, sometimes exceeding 100,000 plates/m. In addition, polymers offer distinct advantages over silica packing for particular applications. Because silica packings are readily degraded by aqueous eluents, they are not always suitable for separations involving ionic species. Polymeric columns are particularly useful in determinations of amino acids, peptides, proteins, organic acids, carbohydrates, and inorganic cations and anions. Polymers are also characterized by exceptional lot-to-lot reproducibility. Reproducibility is often problematic with silica packings, particularly the bonded phases.

Acids↗

Hyperserotonemia and platelet serotonin uptake and release in schizophrenia and affective disorders.

The authors found that platelet serotonin concentrations were significantly elevated in patients with chronic schizophrenia and in patients with bipolar major depressive disorder. High-affinity serotonin uptake was significantly reduced only in patients with bipolar major depressive disorder. Thrombin-induced release of serotonin from platelets in any patient group was not different from that of normal control subjects. Platelet serotonin storage in chronic schizophrenic patients was also not different from that in normal control subjects. These platelet findings could not be explained by age, sex, or medication variables. The authors suggest that the pharmacodynamics of platelet serotonin may be different in chronic schizophrenia than in bipolar major depressive disorder.

Adult↗