How well do second-year students learn physical diagnosis? Observational study of an objective structured clinical examination (OSCE)

BACKGROUND: Little is known about using the Objective Structured Clinical Examination (OSCE) in physical diagnosis courses. The purpose of this study was to describe student performance on an OSCE in a physical diagnosis course. METHODS: Cross-sectional study at Harvard Medical School, 1997–1999, for 489 second-year students. RESULTS: Average total OSCE score was 57% (range 39–75%). Among clinical skills, students scored highest on patient interaction (72%), followed by examination technique (65%), abnormality identification (62%), history-taking (60%), patient presentation (60%), physical examination knowledge (47%), and differential diagnosis (40%) (p < .0001). Among 16 OSCE stations, scores ranged from 70% for arthritis to 29% for calf pain (p < .0001). Teaching sites accounted for larger adjusted differences in station scores, up to 28%, than in skill scores (9%) (p < .0001). CONCLUSIONS: Students scored higher on interpersonal and technical skills than on interpretive or integrative skills. Station scores identified specific content that needs improved teaching

High-resolution solid state carbon-¹³C NMR of bacteriorhodopsin: characterization of [4-¹³C]Asp resonances

Solid state 13C nuclear magnetic resonance measurements of bacteriorhodopsin labeled with [4-13C]Asp show that resonances of single amino acids can be resolved. In order to assign and characterize the resonances of specific Asp residues, three different approaches were used. (1) Determination of the chemical shift anisotropy from side-band intensities provides information about the protonation state of Asp residues. (2) Relaxation studies and T1 filtering allow one to discriminate between resonances with different mobility. (3) A comparison of the spectra of light- and dark-adapted bacteriorhodopsin provides evidence for resonances from aspartic acid residues in close neighborhood of the chromophore. In agreement with other investigations, four resonances are assigned to internal residues. Two of them are protonated in the ground state up to pH 10 (Asp96 and Asp115). All other detected resonances, including Asp85 and Asp212, are due to deprotonated aspartic acid. Two lines due to the two internal deprotonated groups change upon dark and light adaptation, whereas the protonated Asp residues are unaffected

The immunocompetence handicap hypothesis in two sexually dimorphic pinniped species - is there a sex difference in immunity during early development?

The 'immunocompetence handicap hypothesis' predicts that highly sexually dimorphic and polygynous species will exhibit sex differences in immunity. We tested this hypothesis in southern elephant and grey seals during their early development by measuring the following parameters: leucocyte counts, serum IgG levels, erythrocyte sedimentation rate and haematocrit. We failed to find any differences due to sex as assessed by the parameters investigated. Animals were sampled longitudinally during their development and there were significant age effects from birth to weaning in both species. Total and differential leucocyte counts and erythrocyte sedimentation rates increased just prior to weaning then decreased. Haematocrits declined whilst total circulating immunoglobulin G concentrations increased. Body temperatures remained constant throughout the postnatal period. Differences between the species were seen in total leucocyte counts and in polymorphonuclear cells and eosinophils. Southern elephant seals had higher concentrations than grey seals and total leucocyte counts in the former were among the highest reported for mammals