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N Stevens

Publications and source records attributed to N Stevens.

22 records · Page 2Linked to original sources

Conformation of the cytoplasmic domain of phospholamban by NMR and CD.

Nuclear magnetic resonance (NMR) and circular dichroism (CD) spectroscopy have been used to characterize the conformation of the putative cytoplasmic domain of phospholamban (PLB), an oligomeric membrane-bound protein which regulates the activity of the cardiac sarcoplasmic reticulum Ca(2+)-dependent ATPase. In aqueous solution the 25-residue peptide adopts a number of rapidly interconverting conformers with no secondary structural type obviously predominating. However, in trifluoroethanol (TFE) the conformation, while still highly dynamic, is characterized by a high proportion of helical structures. Evidence for this is provided by alpha CH chemical shifts and low NH chemical shift temperature coefficients, small NH-alpha CH intraresidue scalar coupling constants, a substantial number of distinctive interresidue nuclear Overhauser effects (NOEs) [dNN(i, i + 1), d alpha N(i, i + 3), d alpha beta(i, i + 3) and d alpha N(i, i + 4)] and characteristic CD bands at 190 (positive), 206 (negative) and 222 nm (negative). The helicity is interrupted around Pro-21. The activity of PLB is regulated by phosphorylation at either Ser-16 or Thr-17. CD shows that phosphorylation at Ser-16 by the cAMP-activated protein kinase causes about an 11% decrease in alpha-helical content in TFE.

Adenosine Triphosphatases↗

A five-step "microskills" model of clinical teaching.

Teaching family practice residents in a clinical setting is a complex and challenging endeavor, especially for community family physicians teaching part-time and junior faculty members beginning their academic careers. We present a five-step model of clinical teaching that utilizes simple, discrete teaching behaviors or "microskills." The five microskills that make up the model are (1) get a commitment, (2) probe for supporting evidence, (3) teach general rules, (4) reinforce what was done right, and (5) correct mistakes. The microskills are easy to learn and can be readily used as a framework for most clinical teaching encounters. The model has been well received by both community family physicians interested in teaching and newer residency faculty members.

Clinical Competence↗