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991.
Kim WJ Laterza OF Hock KG Pierson-Perry JF Kaminski DM Mesguich M Braconnier F Zimmermann R Zaninotto M Plebani M Hanna A Cembrowski GS Scott MG 《Clinical chemistry》2002,48(7):1028-1034
BACKGROUND: Recent guidelines for use of cardiac troponin to detect cardiac damage and for cardiovascular risk stratification have made increasingly sensitive troponin assays important. Troponin assays continue to be plagued by interferences caused by heterophilic antibodies (HAs). We evaluated the performance of a revised cardiac troponin I (cTnI) assay designed to have increased analytical sensitivity and to minimize the effect of HAs. METHODS: The revised Dade Behring Dimension cTnI assay was evaluated according to NCCLS EP5-A at five institutions. Plasma samples from 14 309 patients were assayed by the original Dimension cTnI assay. To identify samples that may have interfering HAs, samples with values >1.4 microg/L were reanalyzed on the Dade Behring Stratus CS cTnI assay. Samples with possible interfering antibodies were also analyzed before and after selective absorbance studies on the revised Dade Behring Dimension cTnI assay. RESULTS: The limit of quantification in the revised method was 0.1 microg/L with imprecision (CV) of 11-17% at 0.1 microg/L. Values correlated well with the Stratus CS cTnI method: revised = 1.06(original) + 0.01; r = 0.98, S(y/x) = 0.25 microg/L). Falsely increased results consistent with myocardial infarction by the original Dimension cTnI assay and presumably attributable to HAs were identified in 0.17% of all patients with samples submitted for cTnI analysis. The revised Dimension cTnI assay eliminated the interference in 17 of 25 samples identified and greatly decreased the interference in the other 8. CONCLUSIONS: The revised Dimension cTnI method greatly minimizes the effect of interfering HAs. It also exhibits analytical performance characteristics consistent with recent guidelines for use of this assay to detect cardiac damage. 相似文献
992.
Maniscalco M Ferrara G Carratù L Sofia M 《European journal of clinical investigation》2002,32(11):858-861
BACKGROUND: Paranasal sinuses and the nose are important sources of nitric oxide (NO) in humans but the relevance of NO production to the control of nasal airway plasma exudation and its response to inflammatory mediators such as platelet-activating factor (PAF) in healthy subjects is not well known. DESIGN: In this study we aimed to evaluate the effect of the nitric oxide synthase (NOS) inhibitor NG L-arginine methyl ester (L-NAME) on nasal airway plasma extravasation at baseline and after an acute challenge with PAF that induces most symptoms of rhinitis. Eleven healthy subjects were enrolled in the study. Plasma extravasation in the nasal airway was assessed by measuring the albumin content of nasal lavage. RESULTS: PAF challenge caused a significant increase in concentrations of albumin in the nasal lavage fluid (from 0.59 +/- 0.13 mg dL(-1) to 2.46 +/- 0.45 mg dL(-1)) after placebo. Pretreatment with L-NAME significantly prevented the increase of albumin in the nasal lavage fluid induced by PAF as compared to placebo (from 0.53 +/- 0.11 mg dL(-1) to 1.70 +/- 0.28 mg dL(-1); P < 0.005). CONCLUSION: Topical administration of a NO inhibitor is able to attenuate the nasal airway plasma extravasation induced by PAF, suggesting that NO release in vivo is involved in the nasal response to PAF. 相似文献
993.
994.
AUTOGENOUS IMMUNITY TO ENDOGENOUS RNA TUMOR VIRUS : IDENTIFICATION OF ANTIBODY REACTIVITY TO SELECT VIRAL ANTIGENS 总被引:20,自引:5,他引:20 下载免费PDF全文
J. N. Ihle M. G. Hanna Jr. L. E. Roberson F. T. Kenney 《The Journal of experimental medicine》1974,139(6):1568-1581
The viral antigenic determinants recognized in an autogenous immune response in mice against their endogenous C-type virus have been identified by SDS-polyacrylamide gel electrophoresis of immune precipitates between various sera and H3-labeled intact or disrupted AKR leukemia virus. Normal B6C3F1 [(C57BL/6 x C3H/Anf)F1] serum reacts with viral envelope antigens having mol wt of approximately 68,000, 43,000, and 17,000. In addition, minor reactions with viral antigens having mol wts of approximately 19,000 and 15,000 are demonstrable. The 68,000 and 43,000 mol wt antigens can be labeled with [3H]glucosamine and may correspond to the major viral envelope antigens M2 and M1, respectively. The antigens recognized by autogenous immune sera do not differ with respect to age of the animal, nor are they significantly different in sera from various strains of mice (BALB/c, C57BL/6, and C3H/Anf). These results suggest that the age-asociated and strain variations in the autogenous immune response, as determined by radioimmune precipitation assays against intact virus, are due to quantitative and qualitative alterations of antibody levels against common antigens. 相似文献
995.
Hanna B 《Journal of advanced nursing》2001,34(4):456-464
AIMS: This article presents the results of an ethnographic study exploring how teenagers negotiated motherhood. The main aims of the study were to explore how the young women negotiated motherhood and how they constructed their own identities and relationships through teenage parenting. BACKGROUND: Approximately 10% of all births occur to teenage mothers worldwide. This phenomenon is of concern because teenage mothers are reported to be disadvantaged financially, educationally, and cognitively in both the short and long term. Many teenage mothers find strength and fulfillment in their motherhood role but this does not come without cost to themselves or their children, as many teenagers are considered unsuitable to be parents and do not have adequate support. DESIGN: This interpretive study incorporated ethnographic practices and was guided by feminist principles. After ethical approval from the university, data was collected over a 12-month period from five homeless Australian sole-supporting teenage mothers. Methods used included observation, interviews, field notes, journalling, and discussions with key informants. FINDINGS: The five participants described stories of disrupted lives, unhappiness in childhood, turmoil during adolescence and a need to find love and connection in their lives. Analysis of the data revealed four major themes; transforming lives and opportunities for change, accommodating the challenges, tolerating the abandonment of supports and living publicly examined lives. CONCLUSIONS: It was concluded that becoming a sole-supporting mother during the teenage years was a difficult struggle for the young women, because of their youth, their lack of preparation for motherhood and their reliance on welfare supports. In addition, they experienced negative public attitudes directed towards them wherever they went, and this included their visits to community child health centres. Recommendations are made for nurses to take a different approach when working with teenage mothers to help ameliorate the negative impact of poor parenting. 相似文献
996.
Genetic and Molecular Insights Into Genotype‐Phenotype Relationships in Osteopathia Striata With Cranial Sclerosis (OSCS) Through the Analysis of Novel Mouse Wtx Mutant Alleles 下载免费PDF全文
Glenda Comai Agnès Boutet Kristina Tanneberger Filippo Massa Ana‐Sofia Rocha Aurelie Charlet Clara Panzolini Fariba Jian Motamedi Robert Brommage Wolfgang Hans Thomas Funck‐Brentano Martin Hrabe de Angelis Christine Hartmann Martine Cohen‐Solal Jürgen Behrens Andreas Schedl 《Journal of bone and mineral research》2018,33(5):875-887
997.
Agne Laucyte-Cibulskiene Evelina Boreikaite Gediminas Aucina Migle Gudynaite Ilona Rudminiene Sigita Anisko 《Renal failure》2018,40(1):201-208
Vascular calcification (VC) is linked to post-transplant cardiovascular events and hypercalcemia which may influence kidney graft function in the long term. We aimed to evaluate whether pretransplant aortic arch calcification (AoAC) can predict post-transplant cardiovascular or cerebrovascular events (CVEs), and to assess its association with post-transplant plasma calcium levels and renal function in one-year follow-up. Our single-center observational prospective study enrolled 37 kidney transplant recipients (KTR) without previous history of vascular events. Two radiologists evaluated pretransplant AoAC on chest X-ray as suggested by Ogawa et al. in 2009. Cohen’s kappa coefficient was 0.71. The mismatching results were repeatedly reviewed and resulted in consensus. Carotid-femoral (cfPWV) and carotid-radial pulse wave velocity (crPWV) was measured using applanation tonometry before and one year after transplantation. Patient clinical, biochemical data, and cardiovascular/CVE rate were monitored within 1 year. We found out that eGFR1year correlated with eGFRdischarge and calcium based on hospital discharge data (β?=?0.563, p?=?.004 and β?=?51.360, p?=?.026, respectively). Multivariate linear regression revealed that donor age, donor gender, and recipient eGFRdischarge (R-squared 0.65, p?=?.002) better predict eGFR1year than AoAC combined with recipient eGFRdischarge (R-squared 0.35, p?=?.006). During 1-year follow-up, four (10.81%) patients experienced cardiovascular events, which were predicted by PWV ratio (HR 7.549, p?=?.045), but not related to AoAC score (HR 1.044, p?=?.158). In conclusion, KTR without previous vascular events have quite low cardiovascular/CVE rate within 1-year follow-up. VC evaluated as AoAC on pretransplant chest X-ray together with recipient eGFRdischarge could be related to kidney function in one-year follow-up. 相似文献
998.
Paul M Nielsen AD Goldberg E Andreassen S Tacconelli E Almanasreh N Frank U Cauda R Leibovici L;TREAT Study Group 《The Journal of antimicrobial chemotherapy》2007,59(6):1204-1207
BACKGROUND: Prediction of bacterial infections and their pathogens allows for early, directed investigation and treatment. We assessed the ability of TREAT, a computerized decision support system, to predict specific pathogens. METHODS: TREAT uses data available within the first few hours of infection presentation in a causal probabilistic network to predict sites of infection and specific pathogens. We included 3529 patients (920 with microbiologically documented infections) participating in the observational and interventional trials of the TREAT system in Israel, Germany and Italy. Discriminatory performance of TREAT to predict individual pathogens was expressed by the AUC with 95% confidence intervals. Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit statistic. RESULTS: The AUCs for Gram-negative bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella spp. and Escherichia coli, ranged between 0.70 and 0.80 (all significant). Adequate calibration was demonstrated for any Gram-negative infection and individual bacteria, except for E. coli. Discrimination and calibration were acceptable for Enterococcus spp. (AUC 0.71, 0.65-0.78), but not for Staphylococcus aureus (AUC 0.63, 0.55-0.71). The few infections caused by Candida spp. and Clostridium difficile were well predicted (AUCs 0.74, 0.54-0.95; and 0.94, 0.88-1.00, respectively). The coverage with TREAT's recommendation exceeded that observed with physicians' treatment for all pathogens, except Candida spp. CONCLUSIONS: TREAT predicted individual pathogens causing infection well. Prediction of S. aureus was inferior to that observed with other pathogens. TREAT can be used to triage patients by the risk for specific pathogens. The system's predictions enable it to prescribe appropriate antibiotic treatment prior to pathogen identification. 相似文献
999.
Federico De Iure Giorgio Lofrese Pasquale De Bonis Francesco Cultrera Michele Cappuccio Sofia Battisti 《The spine journal》2018,18(6):1005-1013
Background Context
The load sharing classification (LSC) laid foundations for a scoring system able to indicate which thoracolumbar fractures, after short-segment posterior-only fixations, would need longer instrumentations or additional anterior supports.Purpose
We analyzed surgically treated thoracolumbar fractures, quantifying the vertebral body's fragment displacement with the aim of identifying a new parameter that could predict the posterior-only construct failure.Study Design
This is a retrospective cohort study from a single institution.Patient Sample
One hundred twenty-one consecutive patients were surgically treated for thoracolumbar burst fractures.Outcome Measures
Grade of kyphosis correction (GKC) expressed radiological outcome; Oswestry Disability Index and visual analog scale were considered.Methods
One hundred twenty-one consecutive patients who underwent posterior fixation for unstable thoracolumbar burst fractures were retrospectively evaluated clinically and radiologically. Supplementary anterior fixations were performed in 34 cases with posterior instrumentation failure, determined on clinic-radiological evidence or symptomatic loss of kyphosis correction. Segmental kyphosis angle and GKC were calculated according to the Cobb method. The displacement of fracture fragments was obtained from the mean of the adjacent end plate areas subtracted from the area enclosed by the maximum contour of vertebral fragmentation. The “spread” was derived from the ratio between this subtraction and the mean of the adjacent end plate areas. Analysis of variance, Mann-Whitney, and receiver operating characteristic were performed for statistical analysis. The authors report no conflict of interest concerning the materials or methods used in the present study or the findings specified in this paper. No funds or grants have been received for the present study.Results
The spread revealed to be a helpful quantitative measurement of vertebral body fragment displacement, easily reproducible with the current computed tomography (CT) imaging technologies. There were no failures of posterior fixations with preoperative spreads <42% and losses of correction (LOC)<10°, whereas spreads >62.7% required supplementary anterior supports whenever LOC>10° were recorded. Most of the patients in a “gray zone,” with spreads between 42% and 62.7%, needed additional anterior supports because of clinical-radiological evidence of impending mechanical failures, which developed independently from the GKC. Preoperative kyphosis (p<.001), load sharing score (p=.002), and spread (p<.001) significantly affected the final surgical treatment (posterior or circumferential).Conclusions
Twenty-two years after the LSC, both improvements in spinal stabilization systems and software imaging innovations have modified surgical concepts and approach on spinal trauma care. Spread was found to be an additional tool that could help in predicting the posterior construct failure, providing an objective preoperative indicator, easily reproducible with the modern viewers for CT images. 相似文献1000.
Simone M. Sint Nicolaas Peter M. Hoogerbrugge Esther M. M. van den Bergh José A. E. Custers Sofia Gameiro Reinoud J. B. J. Gemke Chris M. Verhaak 《Supportive care in cancer》2016,24(11):4503-4513