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81.
Kerrigan CL Collins ED Kneeland TS Voigtlaender D Moncur MM Matheney TH Grove MR Tosteson AN 《Plastic and reconstructive surgery》2000,106(2):280-288
The purpose of this article is to introduce the measurement of utilities, or patient preferences, to the plastic surgery community. Specifically, the study demonstrated the development and validation of a utility measure for estimating the health-related quality of life in women with breast hypertrophy. Two self-administered instruments were developed, a Wheel and a Table. All subjects completed the utility assessments for their "current health" and again for "breast-related symptoms." The reliability of the instruments was assessed in repeat (test-retest) interviews of 47 women within 10 to 18 days. Utilities obtained with the new instruments were also compared with the performance of other validated utility assessment instruments, including a visual analogue scale, a computer-based instrument (U-Titer), and a preference classification system (EuroQol). Of the 47 women in the test-retest reliability study, 21 had experienced breast hypertrophy (13 had not had reduction surgery and 8 had undergone reduction mammaplasty). Mean utility values for breast-related symptoms among women with breast hypertrophy (n = 13) were: Table, 0.85; Wheel, 0.90; and U-Titer, 0.66. Current health utility scores were significantly lower for women with breast hypertrophy (n = 13), as measured by all instruments except the Wheel. The Table had good reliability and distinguished women with breast hypertrophy from those without. Although the Table provided higher utility values for the same health state compared with the computer-based interview (U-Titer), it is much less costly to implement. The Table is recommended as a reasonable alternative for use in multicenter studies of women with breast hypertrophy. The reported utility value for breast hypertrophy of 0.86 is much lower than predicted. It is comparable with the reported burden of living with other health conditions, such as moderate angina (0.90) and a kidney transplant (0.84). 相似文献
82.
Robert A. Montgomery Michael T. Geraghty Evelyn Bull Bruce D. Gelb Maureen Johnson Iain McIntosh Clair A. Francomano Harry C. Dietz 《American journal of human genetics》1998,63(6):1703-1711
Mutations in the FBN1 gene, which encodes fibrillin-1, cause Marfan syndrome (MFS) and have been associated with a wide range of milder, overlap phenotypes. The factors that modulate phenotypic severity, both between and within families, remain to be determined. This study examines the relationship between the FBN1 genotype and phenotype in families with extremely mild phenotypes and in those that show striking clinical variation among apparently affected individuals. In one family, clinically similar but etiologically distinct disorders are segregating independently. In another, somatic mosaicism for a mutant FBN1 allele is associated with subdiagnostic manifestations, whereas germ-line transmission of the identical mutation causes severe and rapidly progressive disease. A third family cosegregates mild mitral valve prolapse syndrome with a mutation in FBN1 that can be functionally distinguished from those associated with the classic MFS phenotype. These data have immediate relevance for the diagnostic and prognostic counseling of patients and their family members. 相似文献
83.
Mary C. Carson Maureen A. Ngoh Stephen W. Hadley 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,712(1-2)
A confirmation procedure is described for detection of residues of six tetracyclines in bovine milk, and oxytetracycline in shrimp. Residues are extracted from milk or shrimp tissue using metal chelate affinity chromatography. The extracts are desalted, further concentrated using polymeric solid-phase extraction, and chromatographed on a polymeric reversed-phase column. Analysis is by methane negative ion chemical ionization on a quadrupole mass spectrometer using a particle beam interface. Data are acquired in partial scan mode, monitoring from m/z 378 to m/z 480. The procedure was validated with control milk and shrimp, fortified milk (30 ng/ml) and shrimp (100 ng/g), and milk and tissue from animals treated with the drugs. 相似文献
84.
Alveolar oxygen uptake and femoral artery blood flow dynamics in upright and supine leg exercise in humans 总被引:9,自引:0,他引:9
MacDonald Maureen J.; Shoemaker J. Kevin; Tschakovsky Michael E.; Hughson Richard L. 《Journal of applied physiology》1998,85(5):1622-1628
We tested the hypothesis that the slowerincrease in alveolar oxygen uptake(O2) at the onset ofsupine, compared with upright, exercise would be accompanied by aslower rate of increase in leg blood flow (LBF). Seven healthy subjectsperformed transitions from rest to 40-W knee extension exercise in theupright and supine positions. LBF was measured continuously with pulsedand echo Doppler methods, andO2 was measured breath bybreath at the mouth. At rest, a smaller diameter of thefemoral artery in the supine position(P < 0.05) was compensated by agreater mean blood flow velocity (MBV) (P < 0.05) so that LBF was not different in the two positions. At the end of6 min of exercise, femoral artery diameter was larger in the uprightposition and there were no differences inO2, MBV, or LBF betweenupright and supine positions. The rates of increase ofO2 and LBF in thetransition between rest and 40 W exercise, as evaluated by the meanresponse time (time to 63% of the increase), were slower in the supine[O2 = 39.7 ± 3.8 (SE) s, LBF = 27.6 ± 3.9 s] than in the uprightpositions (O2 = 29.3 ± 3.0 s, LBF = 17.3 ± 4.0 s;P < 0.05). These data support ourhypothesis that slower increases in alveolarO2 at the onset of exercisein the supine position are accompanied by a slower increase in LBF. 相似文献
85.
Raphael Saginur Stephen S. Silver Richard Bonin Maureen Carlier Manuel Orizaga 《CMAJ》1985,133(12):1228-1230
86.
Multicopper oxidase-3 is a laccase associated with the peritrophic matrix of Anopheles gambiae 总被引:1,自引:0,他引:1
The multicopper oxidase (MCO) family of enzymes includes laccases, which oxidize a broad range of substrates including polyphenols and phenylendiamines; ferroxidases, which oxidize ferrous iron; and several other oxidases with specific substrates such as ascorbate, bilirubin or copper. The genome of Anopheles gambiae, a species of mosquito, encodes five putative multicopper oxidases. Of these five, only AgMCO2 has known enzymatic and physiological functions: it is a highly conserved laccase that functions in cuticle pigmentation and tanning by oxidizing dopamine and dopamine derivatives. AgMCO3 is a mosquito-specific gene that is expressed predominantly in adult midguts and Malpighian tubules. To determine its enzymatic function, we purified recombinant AgMCO3 and analyzed its activity. AgMCO3 oxidized hydroquinone (a p-diphenol), the five o-diphenols tested, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), and p-phenylenediamine, but not ferrous iron. The catalytic efficiencies of AgMCO3 were similar to those of cuticular laccases (MCO2 orthologs), except that AgMCO3 oxidized all of the phenolic substrates with similar efficiencies whereas the MCO2 isoforms were less efficient at oxidizing catechol or dopa. These results demonstrate that AgMCO3 can be classified as a laccase and suggest that AgMCO3 has a somewhat broader substrate specificity than MCO2 orthologs. In addition, we observed AgMCO3 immunoreactivity in the peritrophic matrix, which functions as a selective barrier between the blood meal and midgut epithelial cells, protecting the midgut from mechanical damage, pathogens, and toxic molecules. We propose that AgMCO3 may oxidize toxic molecules in the blood meal leading to detoxification or to cross-linking of the molecules to the peritrophic matrix, thus targeting them for excretion. 相似文献
87.
In this paper we examine some ecological consequences and phenotypic correlates of flower size variation in wild radish, Raphanus sativus. Mean corolla diameter varied significantly among individuals within natural populations of R. sativus in California. On the average, almost 40% of flower biomass was allocated to corolla tissue. In field experiments, pollinator visitation increased significantly with corolla size. Large flowers also accumulated more nectar when pollinators were excluded from plants. In three populations, corolla size was positively correlated with allocation to pollen per flower (either anther weight or pollen grain number), but there was usually no phenotypic relationship between corolla size and several measures of female allocation (ovule number per flower, proportion fruit set, and total seed mass per fruit). Plants growing in the field produced fewer large flowers per unit of stem, and stem biomass was negatively related to corolla size for plants grown under controlled greenhouse conditions. Male and female fitness may covary differently with allocation to attractive floral features in species such as R. sativus, where seed production is often limited by resources rather than by pollen. 相似文献
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