Computer searching of the medical literature.
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Biomedical subjects
Publications and source records attributed to D Porter.
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Male (n = 25) and female (n = 14) competitive swimmers were studied during tethered (breaststroke) and free (front crawl) swimming to determine the validity of calculating exercise oxygen uptake (VO2) from expired gas samples taken immediately after the activity. Based on a single 20-s recovery VO2, the swimmers' VO2 max was correlated with performance in a 400-yd (365.8-m) front crawl swim. The best predictors of VO2 max for trained swimmers were lean body weight and stroke index (r = 0.97). The single best predictor of performance in the 365.8-m front crawl swim was the distance per stroke (r = 0.88), whereas the combination of distance per stroke and VO2 max (ml/kg LBW/min) correlated 0.97 with performance in the swim. This study demonstrates that it is possible to accurately determine the VO2 during maximal and submaximal swimming using a single, 20-s expired gas collection taken immediately after a 4-7 min swim. These findings demonstrate the importance of stroke technique on the energy cost and variations in performance during competitive swimming.
Simian adenovirus 7 (SA7) is a highly oncogenic virus, capable of causing tumors in hamsters upon the direct injection of viral DNA. We determined the transcriptional organization of the transforming region and compared it with that of the human adenoviruses. This analysis demonstrated that there are two independently promoted transcription units similar to the E1a and E1b regions of the human adenoviruses. The nucleotide sequence of the SA7 E1a region demonstrated considerable homology with the human adenoviruses, both in the sequences that regulate E1a expression and in the encoded polypeptides. The amino acid homology was reflected in the ability of SA7 to complement the growth of human adenoviruses mutant in the E1a region. Furthermore, we found two regions of amino acid homology unique to SA7 and the highly oncogenic human adenovirus 12.
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A method was developed to determine the susceptibility of Haemophilus influenzae to ampicillin, cefamandole, and chloramphenicol by using the MS-2 system (Abbott Laboratories) for determining minimum inhibitory concentrations (MIC). The MS-2 results for 132 strains of H. influenzae were compared with the results of agar disk diffusion, agar dilution, and beta-lactamase tests. Twenty-four strains (18.2%) of H. influenzae were resistant to ampicillin by the agar dilution method, as opposed to 25 strains by the MS-2 method. For a beta-lactamase-negative strain, the agar dilution MIC was 4 micrograms/ml, and the MS-2 MIC was 16 micrograms/ml. Twenty-one strains produced beta-lactamase; two beta-lactamase-negative strains were resistant by MS-2, agar dilution, and agar disk diffusion. In addition, one beta-lactamase-negative strain, for which the agar dilution MIC was 32 micrograms/ml and the MS-2 MIC was 16 micrograms/ml, was sensitive by agar disk diffusion. Overall, the MS-2 method compared favorably with the agar dilution method for determining the MIC of ampicillin, cefamandole, and chloramphenicol for H. influenzae.
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The accurate, voice entry of radiologic reports into a computer takes significantly longer than entry by keyboard. Careful speech and considerable patience are required to avoid an unacceptably high error-rate. With improvements in the future, this technology may compete with the conventional technology.
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