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81.
The use of analytical chemistry measurements in environmental monitoring is dependent on an assessment of measurement error. Models for variation in measurements are needed to quantify uncertainty in measurements, set limits of detection, and preprocess data for more sophisticated analysis in prediction, classification, and clustering. This article explains how a two-component error model can be used to accomplish all of these objectives. In addition, we present applications to quantitating biomarkers of exposure to toxic substances using gene expression microarrays. 相似文献
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BACKGROUND: Indwelling arterial lines are commonly used in critical care. To standardize and improve the placement of these devices, we developed and implemented a respiratory therapist-based line placement service. As a measure of the quality of the service, we assessed the success and complications encountered in the first 119 line placement attempts of this new service. METHODS: The following were recorded for each artery on which cannulation was attempted: the number of the attempt on which cannulation was successful; if a different person was able to cannulate the artery after initial failure; and whether any complications occurred. Success rate compared to the number of attempts was tested with chi-square. RESULTS: Respiratory therapists were successful in placing 80% of attempted lines on the first try, including all 18 of 18 dorsal pedis attempts. Ninety-seven percent (115 of 119) of attempted arteries were ultimately cannulated. Success on second attempts by the same person was less than if a different, more experienced, person attempted the placement (p = 0.024). No complications were identified during the study. CONCLUSIONS: Initiation of a respiratory therapist-based arterial line placement service resulted in an acceptable cannulation success rate, without complications. Increased experience of the person attempting cannulation correlates with improved success. 相似文献
85.
Yokel RA Fredenburg AM Durbin PW Xu J Rayens MK Raymond KN 《Journal of pharmaceutical sciences》2000,89(4):545-555
Bidentate hydroxypyridinone chelators effectively complex and facilitate excretion of trivalent iron. To test the hypothesis that hexadentate chelators are more effective than bidentate chelators at low concentrations, urinary and biliary Fe excretions were determined in Fe-loaded rats before and after administration of a bidentate chelator, Pr-(Me-3,2-HOPO), or its hexadentate analogue, TREN-(Me-3,2-HOPO). The bidentate chelator slightly increased biliary Fe excretion in Fe-loaded rats after IV (90 micromol/kg) and PO (90 or 270 micromol/kg) administration, but chelation efficiency did not exceed 1%. The hexadentate chelator markedly increased biliary Fe excretion, achieving overall chelation efficiencies of 14% after IV administration of 30 micromol/kg and 8 or 3% after PO (30 or 90 micromol/kg) administration. The hexadentate chelator was significantly more effective than the bidentate chelator after IV injection and oral dosing. In chelator-treated Fe-loaded or saline-injected rats, >90% of the excreted Fe was in the bile. Oral TREN-(Me-3,2-HOPO), given to non-Fe-loaded rats, did not appreciably change Fe output, indicating that there was little Fe depletion in the absence of Fe overload. These results support the hypothesis that greater Fe chelation efficiency can be achieved with hexadentate than with bidentate chelators at lower, and presumably safer, concentrations. The results also demonstrate that TREN-(Me-3, 2-HOPO) is a promising, orally effective, Fe chelator. 相似文献
86.
GM Durbin NJ Hunter N McIntosh EO Reynolds PD Wimberley 《Archives of disease in childhood》1976,51(3):163-169
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131). 相似文献
87.
The Natural History of Flare‐Ups in Fibrodysplasia Ossificans Progressiva (FOP): A Comprehensive Global Assessment
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Robert J Pignolo Christopher Bedford‐Gay Moira Liljesthröm Blythe P Durbin‐Johnson Eileen M Shore David M Rocke Frederick S Kaplan 《Journal of bone and mineral research》2016,31(3):650-656
Fibrodysplasia ossificans progressiva (FOP) leads to disabling heterotopic ossification (HO) from episodic flare‐ups. However, the natural history of FOP flare‐ups is poorly understood. A 78‐question survey on FOP flare‐ups, translated into 15 languages, was sent to 685 classically‐affected patients in 45 countries (six continents). Five hundred patients or knowledgeable informants responded (73%; 44% males, 56% females; ages: 1 to 71 years; median: 23 years). The most common presenting symptoms of flare‐ups were swelling (93%), pain (86%), or decreased mobility (79%). Seventy‐one percent experienced a flare‐up within the preceding 12 months (52% spontaneous; 48% trauma‐related). Twenty‐five percent of those who had received an intramuscular injection reported an immediate flare‐up at the injection site, 84% of whom developed HO. Axial flare‐ups most frequently involved the back (41.6%), neck (26.4%), or jaw (19.4%). Flare‐ups occurred more frequently in the upper limbs before 8 years of age, but more frequently in the lower limbs thereafter. Appendicular flare‐ups occurred more frequently at proximal than at distal sites without preferential sidedness. Seventy percent of patients reported functional loss from a flare‐up. Thirty‐two percent reported complete resolution of at least one flare‐up and 12% without any functional loss (mostly in the head or back). The most disabling flare‐ups occurred at the shoulders or hips. Surprisingly, 47% reported progression of FOP without obvious flare‐ups. Worldwide, 198 treatments were reported; anti‐inflammatory agents were most common. Seventy‐five percent used short‐term glucocorticoids as a treatment for flare‐ups at appendicular sites. Fifty‐five percent reported that glucocorticoids improved symptoms occasionally whereas 31% reported that they always did. Only 12% reported complete resolution of a flare‐up with glucocorticoids. Forty‐three percent reported rebound symptoms within 1 to 7 days after completing a course of glucocorticoids. This study is the first comprehensive global assessment of FOP flare‐ups and establishes a critical foundation for the design and evaluation of future clinical trials. © 2015 American Society for Bone and Mineral Research. 相似文献
88.
G N Stradling S A Gray J C Moody A Hodgson K N Raymond P W Durbin S J Rodgers D L White P N Turowski 《International journal of radiation biology》1991,59(5):1269-1277
A hydroxypridinone derivative of desferrioxamine (Na-DFO-HOPO), a dihydroxamic derivative of diethylenetriaminepenta-acetic acid (ZnNa-DTPA-DX), and DTPA (CaNa3- and ZnNa3-DTPA) were tested at dosages of 30 mumol kg-1 for their ability to remove 238Pu or 241Am from rats after their intravenous injection as citrate or inhalation as nitrate. The most effective treatment regimen for injected Pu was the repeated administration of DFO-HOPO; by 7 days the body content was reduced to 8% of that in untreated animals. Repeated dosages of 3 mumol kg-1 DFO-HOPO were as effective as those of 30 mumol kg-1 DTPA. After inhalation of Pu nitrate, repeated treatment with DTPA, DTPA-DX or DFO-HOPO reduced the body content by 7 days to, respectively, 10, 15 and 31% of those in untreated animals. After inhalation of Am, DTPA-DX and DTPA were equally effective, the body contents being reduced to 7% of control values with repeated treatment. Injection of DFO-HOPO was ineffective for enhancing the elimination of inhaled or injected Am. The results confirm the strategy of examining the use of siderophore analogues for the decorporation of Pu or Am. However, at present DTPA should remain the agent of choice, particularly after inhalation. 相似文献
89.
AIDS Knowledge, Attitudes, and Behavior Among Inner City, Junior High School Students 总被引:3,自引:0,他引:3
David Siegel MD MPH Flora Krasnovsky MA Meg Durbin MD Margaret Chesney PhD Nancy Lazarus MD MPH 《The Journal of school health》1991,61(4):160-165
To gain information about AIDS knowledge, attitudes, and behavior of junior high school students, 1,967 students in three junior high schools in an inner city school district were surveyed. Ages of the participants ranged from 11-16 years, and 48% were male. Ethnically, 33% were Asian, 31% African-American, 24% Latino, and 5% white. African-American students had greater AIDS general knowledge than Asians and similar general knowledge to Latinos and whites. Most students wanted to be taught about AIDS in school. Misconceptions about casual contagion of AIDS were common. Students with these misconceptions were more likely to believe that students with AIDS should not be allowed to attend school. A high proportion of students had engaged in high-risk behavior including sexual intercourse, drinking alcoholic beverages, and using street drugs. More boys than girls reported each of these activities. Of individuals having had sexual intercourse, a positive association was found between the belief that condoms are effective in preventing HIV infection and use of condoms. These findings support the possibility that improving knowledge about HIV transmission would result in more tolerance toward students with HIV infection and would result in less high-risk behavior. 相似文献
90.