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Will Kaufman Augustine S Chavez Betty Skipper Arthur Kaufman 《International journal for equity in health》2006,5(1):6-5
Background
A public hospital in New Mexico required collection of 50% of estimated costs prior to elective surgeries for self-pay patients. This study assesses the impact of this policy on access to elective surgical procedures. 相似文献4.
New technology has allowed the creation of single catheters with up to four separate luminal channels for access to the central venous system. Since cancer chemotherapy may be associated with local complications specifically related to the mode of intravenous administration, temporary central venous access with a multiple lumen catheter (MLC) offers distinct theoretical advantages over previously used peripheral venous sites. As part of a prospective study to evaluate the clinical efficacy of MLC, the authors have separately studied the usefulness of these catheters in providing venous access to patients receiving chemotherapy. 相似文献
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S Kaufman 《The Journal of pediatrics》1989,114(5):895-900
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Propofol for patients with Huntington''s chorea? 总被引:2,自引:0,他引:2
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Further studies of the role of Ser-16 in the regulation of the activity of phenylalanine hydroxylase. 总被引:3,自引:1,他引:2
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D Kowlessur X J Yang S Kaufman 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(11):4743-4747
It was previously proposed that the activation of rat liver phenylalanine hydroxylase (EC 1.14.16.1) by cAMP-dependent protein kinase-mediated phosphorylation of Ser-16 is due to the introduction of the negatively charged phosphate group. To explore the validity of this proposal, we have applied site-directed mutagenesis to specifically replace Ser-16 with negatively charged amino acids, glutamic and aspartic; with polar uncharged amino acids, asparagine and glutamine; with the positively charged amino acid lysine; and with the nonpolar hydrophobic amino acid alanine. The wild-type and mutant enzymes were purified to homogeneity, and the importance of Ser-16 in the activation of phenylalanine hydroxylase was examined by comparing the state of activation of the phosphorylated form of the wild-type hydroxylase with that of the mutants. The kinetic studies carried out on the wild-type phosphorylated hydroxylase showed that all the activation could be accounted for by an increase in Vmax with no change in Km for either phenylalanine or the pterin cofactor. Replacement of Ser-16 with a negatively charged residue, glutamate of aspartate, resulted in the activation of the hydroxylase by 2- to 4-fold, whereas replacement with glutamine, asparagine, lysine, or alanine resulted in a much more modest increase. Further, lysolecithin was found to stimulate the phosphorylated hydroxylase and the mutant enzymes S16E and S16D by a factor of 6-7. In contrast, the mutants S16Q, S16N, and S16A all showed the same magnitude of activation as the wild-type with lysolecithin. Therefore, this study demonstrates that activation of the enzyme by phosphorylation of Ser-16 by cAMP-dependent protein kinase is due to the introduction of negative charge(s) and strongly suggests the involvement of electrostatic interaction between the regulatory and catalytic domains of the hydroxylase. 相似文献
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Laura L S Howe Ashton M Anderson David A S Kaufman Bonnie C Sachs David W Loring 《Archives of clinical neuropsychology》2007,22(6):753-761
We prospectively evaluated performance of 63 referrals to a memory disorders clinic who received the Medical Symptom Validity Test (MSVT) as part of their standard neuropsychological evaluation. The patients were grouped based on independent medical diagnoses and presence or absence of a potential financial incentive to under-perform. Twenty-seven patients (42.9%) scored below cutoffs on the MSVT symptom validity indices. Two individuals in the potential financial incentive group showed clear signs of invalid responding (18.2%). Twenty-two of the remaining 25 patients who failed the symptom validity indices corresponded to the dementia profile. Three individuals did not correspond to the dementia profile but are thought to have performed validly representing a 4.8% false positive rate. When considering all MSVT indices, the base rate of invalid responding in the potential financial incentive to under-perform group increased to 27.3%. Combining all groups our base rate of invalid responding was 4.8%. Specific performances are presented. 相似文献