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101.
Jaclyn Anderson Harlan Sayles Jeffrey R. Curtis Fred Wolfe Kaleb Michaud 《Arthritis care & research》2010,62(10):1481-1488
Objective
The Stanford Health Assessment Questionnaire Disability Index (HAQ) is the gold standard functional status questionnaire in rheumatology, but it is lengthy. Three shorter versions, the modified HAQ (MHAQ), the Multidimensional HAQ (MDHAQ), and the HAQII are often used in outcomes research as HAQ substitutes. We developed conversion formulas between these modified versions and the original HAQ.Methods
Analysis was limited to the comparison of rheumatoid arthritis (RA) patients at a random observation when the HAQ was recorded in conjunction with the MHAQ (n = 29,596), the MDHAQ (n = 13,665), or the HAQII (n = 15,823). Development models were randomly limited to 80% of the data (development sample) and the remaining 20% was used for model validation.Results
Two conversion formulas were developed for each of the MHAQ, the MDHAQ, and the HAQII: a short model and a long model inclusive of questions common to both the modified measures and the original HAQ. Short models explained 81–83%, and long models 82–86%, of the variance. Predicted HAQ values of zero were assigned to all cases with an MDHAQ or HAQII score of zero, with remaining cases used for model estimation. Bland‐Altman plots demonstrated good concordance between actual and predicted values for each measure. The validation sample closely approximated the results from the development sample (0.005 ≤ ΔR2 ≤ 0.009) for each measure.Conclusion
We have developed and validated highly accurate conversion formulas from the MHAQ, MDHAQ, and HAQII to the original HAQ in a large sample of RA patients. The developed models are useful for conversion of measures in the research setting. Because of substantial variability at the individual patient level, application of the formulas to individual patients is inadvisable. 相似文献102.
The binding motif of human CTLA-4 is well known to be MYPPPY and for porcine CTLA-4 the binding motif is LYPPPY. Is this single amino acid difference of methionine (M) versus leucine (L) critical for the CTLA-4 binding? Recently, we have reported that the recombinant soluble porcine CTLA-4 was incapable of binding to human CD80. In this study we mutated L to M in the binding motif of the soluble porcine CTLA-4 and mutated M to L in the binding motif of the soluble human CTLA-4. We then analyzed how these mutations affected the binding affinity of the mutants to both porcine and human CD80+ cells. The soluble porcine CTLA-4-L97M mutant partially lost its binding affinity to porcine CD80 compared to the wild-type and conferred very weak binding ability to human CD80. These results indicate that the L in the binding motif of porcine CTLA-4 is important for determining its binding ability to porcine CD80. Wild-type soluble human CTLA-4 binds to both human and porcine CD80 with comparable affinity, however, the soluble human CTLA-4-M97L mutant almost lost its binding ability to human CD80 and increased its binding ability to porcine CD80. These results indicate that M in the human CTLA-4 binding motif is extremely critical for its binding to human CD80. Those data suggest that the human CTLA-4 based recombinant protein drugs such as human CTLA-4-Ig can be used and/or tested in a porcine model. Conversely, the use of porcine CTLA-4 based recombinant protein drugs such as porcine CTLA-4-Ig is restricted to swine models. The difference in binding specificity of CTLA-4 observed in this study may be useful for studies such as pig to nonhuman primate xeno-transplantation. Porcine CTLA-4- and human CTLA-4-M97L mutant-based recombinant protein drugs can be used to specifically block the direct presentation by donor antigen presenting cells in pig to nonhuman primate xeno-transplantation. Human CTLA-4-M97L mutant-based recombinant protein drugs will be more ideal as it is without immunogenicity to human being. 相似文献
103.
C E Quin 《Journal of the Royal Society of Medicine》1994,87(7):393-395
Galen's teaching on anatomy and physiology was generally accepted in the Middle Ages and this applies to the part he thought was played by the pneuma in the functions of the body. In this essay I have outlined the advances made after Galen in the study of the nervous system leading eventually to a time when the soul and the pneuma were no longer thought necessary for the proper functioning of the brain and nerves. 相似文献
104.
John Quin 《British medical journal》2004,328(7455):1571
105.
Heerema NA Raimondi SC Anderson JR Biegel J Camitta BM Cooley LD Gaynon PS Hirsch B Magenis RE McGavran L Patil S Pettenati MJ Pullen J Rao K Roulston D Schneider NR Shuster JJ Sanger W Sutcliffe MJ van Tuinen P Watson MS Carroll AJ 《Genes, chromosomes & cancer》2007,46(7):684-693
Children with acute lymphoblastic leukemia (ALL) and high hyperdiploidy (>50 chromosomes) are considered to have a relatively good prognosis. The specific extra chromosomes are not random; extra copies of some chromosomes occur more frequently than those of others. We examined the extra chromosomes present in high hyperdiploid ALL to determine if there were a relation of the specific extra chromosomes and modal number (MN) and if the extra chromosomes present could differentiate high hyperdiploid from near-triploid and near-tetraploid cases. Karyotypes of 2,339 children with ALL and high hyperdiploidy at diagnosis showed a distinct nonrandom sequential pattern of gain for each chromosome as MN increased, with four groups of gain: chromosomes 21, X, 14, 6, 18, 4, 17, and 10 at MN 51-54; chromosomes 8, 5, 11, and 12 at MN 57-60; chromosomes 2, 3, 9,16, and 22 at MN 63-67; chromosomes 1, 7 13, 15, 19, and 20 at MN 68-79, and Y only at MN >or=80. Chromosomes gained at lower MN were retained as the MN increased. High hyperdiploid pediatric ALL results from a single abnormal mitotic division. Our results suggest that the abnormal mitosis involves specific chromosomes dependent on the number of chromosomes aberrantly distributed, raising provocative questions regarding the mitotic mechanism. The patterns of frequencies of tetrasomy of specific chromosomes differs from that of trisomies with the exception of chromosome 21, which is tetrasomic in a high frequency of cases at all MN. These results are consistent with different origins of high hyperdiploidy, near-trisomy, and near-tetrasomy. 相似文献
106.
Wei Xiong Eric Hollingsworth Jack Muckstadt Jaclyn Van Lieu Vorenkamp Eliot J Lazar Nicholas V Cagliuso Nathaniel Hupert 《Infection control and hospital epidemiology》2007,28(5):618-621
Hospital preparedness for nosocomial or community-wide outbreaks of communicable disease includes the capability for rapid, self-reliant administration of prophylaxis to its workforce, with the goal of minimal disruption of patient care, here called hospital "self-prophylaxis." We created a new discrete-event simulation model of a hypothetical hospital wing to compare the operational charateristics of standard single-line, "first-come, first-served" dispensing clinics with those of 2 staff management strategies that can dramatically reduce staff waiting time while centralizing dispensing around existing pharmacy-distribution points. 相似文献
107.
J D Quin 《The Quarterly journal of medicine》1992,82(298):81-90
108.
109.
Quin E. Denfeld James O. Mudd Wohaib Hasan Jill M. Gelow Shirin O. Hiatt Kerri Winters-Stone Christopher S. Lee 《Heart & lung : the journal of critical care》2018,47(4):281-284