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81.
Hernaez R Lazo M Bonekamp S Kamel I Brancati FL Guallar E Clark JM 《Hepatology (Baltimore, Md.)》2011,54(3):1082-1090
Ultrasonography is a widely accessible imaging technique for the detection of fatty liver, but the reported accuracy and reliability have been inconsistent across studies. We aimed to perform a systematic review and meta-analysis of the diagnostic accuracy and reliability of ultrasonography for the detection of fatty liver. We used MEDLINE and Embase from October 1967 to March 2010. Studies that provided cross-tabulations of ultrasonography versus histology or standard imaging techniques, or that provided reliability data for ultrasonography, were included. Study variables were independently abstracted by three reviewers and double checked by one reviewer. Forty-nine (4720 participants) studies were included for the meta-analysis of diagnostic accuracy. The overall sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of ultrasound for the detection of moderate-severe fatty liver, compared to histology (gold standard), were 84.8% (95% confidence interval: 79.5-88.9), 93.6% (87.2-97.0), 13.3 (6.4-27.6), and 0.16 (0.12-0.22), respectively. The area under the summary receiving operating characteristics curve was 0.93 (0.91-0.95). Reliability of ultrasound for the detection of fatty liver showed kappa statistics ranging from 0.54 to 0.92 for intrarater reliability and from 0.44 to 1.00 for interrater reliability. Sensitivity and specificity of ultrasound was similar to that of other imaging techniques (i.e., computed tomography or magnetic resonance imaging). Statistical heterogeneity was present even after stratification for multiple clinically relevant characteristics. Conclusion: Ultrasonography allows for reliable and accurate detection of moderate-severe fatty liver, compared to histology. Because of its low cost, safety, and accessibility, ultrasound is likely the imaging technique of choice for screening for fatty liver in clinical and population settings. 相似文献
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84.
Martin Tibuakuu Miranda R. Jones Ana Navas-Acien Di Zhao Eliseo Guallar Amanda J. Gassett Lianne Sheppard Matthew J. Budoff Joel D. Kaufman Erin D. Michos 《Environmental health : a global access science source》2017,16(1):133
Background
Long-term exposure to high ambient air pollution has been associated with coronary artery calcium (CAC), a marker of cardiovascular disease (CVD). Calcifications of left-sided heart valves are also markers of CVD risk. We investigated whether air pollution was associated with valvular calcification and its progression.Methods
We studied 6253 MESA participants aged 45–84 years who underwent two cardiac CT scans 2.5 years apart to quantify aortic valve calcium (AVC) and mitral annular calcium (MAC). CAC was included for the same timeframe for comparison with AVC/MAC. Ambient particulate matter <2.5 μm (PM2.5) and oxides of nitrogen (NOx) concentrations were predicted from residence-specific spatio-temporal models.Results
The mean age (SD) of the study sample was 62 (10) years, 39% were white, 27% black, 22% Hispanic, and 12% Chinese. The prevalence of AVC and MAC at baseline were 13% and 9% respectively, compared to 50% prevalence of CAC. The adjusted prevalence ratios of AVC and MAC for each 5 μg/m3 higher PM2.5 was 1.19 (95% CI 0.87, 1.62) and 1.20 (0.81, 1.77) respectively, and for CAC was 1.14 (1.01, 1.27). Over 2.5 years, the mean change in Agatston units/year for each 5 μg/m3 higher PM2.5 concentration was 0.29 (?5.05, 5.63) for AVC and 4.38 (?9.13, 17.88) for MAC, compared to 8.66 (0.61, 16.71) for CAC. We found no significant associations of NOx with AVC and MAC.Conclusion
Our findings suggest a trend towards increased 2.5-year progression of MAC with exposure to outdoor PM2.5, although this association could not be confirmed. Additional well-powered studies with longer periods of follow-up are needed to further study associations of air pollution with valvular calcium.Trial registration
Although MESA is not a clinical trial, this cohort is registered at ClinicalTrials.gov Identifier: NCT00005487; Date of registration May 25, 2000.85.
86.
Karliner LS Napoles-Springer AM Schillinger D Bibbins-Domingo K Pérez-Stable EJ 《Journal of general internal medicine》2008,23(10):1555-1560
Background
Standardized means to identify patients likely to benefit from language assistance are needed.Objective
To evaluate the accuracy of the U.S. Census English proficiency question (Census-LEP) in predicting patients’ ability to communicate effectively in English.Design
We investigated the sensitivity and specificity of the Census-LEP alone or in combination with a question on preferred language for medical care for predicting patient-reported ability to discuss symptoms and understand physician recommendations in English.Participants
Three hundred and two patients > 18 who spoke Spanish and/or English recruited from a cardiology clinic and an inpatient general medical-surgical ward in 2004–2005.Results
One hundred ninety-eight (66%) participants reported speaking English less than “very well” and 166 (55%) less than “well”; 157 (52%) preferred receiving their medical care in Spanish. Overall, 135 (45%) were able to discuss symptoms and 143 (48%) to understand physician recommendations in English. The Census-LEP with a high-threshold (less than “very well”) had the highest sensitivity for predicting effective communication (100% Discuss; 98.7% Understand), but the lowest specificity (72.6% Discuss; 67.1% Understand). The composite measure of Census-LEP and preferred language for medical care provided a significant increase in specificity (91.9% Discuss; 83.9% Understand), with only a marginal decrease in sensitivity (99.4% Discuss; 96.7% Understand).Conclusions
Using the Census-LEP item with a high-threshold of less than “very well” as a screening question, followed by a language preference for medical care question, is recommended for inclusive and accurate identification of patients likely to benefit from language assistance. (246 words) 相似文献87.
Alberto Talaya Estela Giménez José Luis Piñana Eliseo Albert Juan Carlos Hernández-Boluda Ariadna Pérez Ignacio Torres Carlos Solano David Navarro 《Journal of medical virology》2019,91(6):1128-1135
It has been reported that low-plasma cytomegalovirus (CMV) DNA loads are associated with an increased risk of overall mortality in allogeneic hematopoietic stem cell transplantation (allo-HSCT). Utilizing a conservative strategy for initiation of preemptive antiviral therapy (>1500 IU/mL), we characterized the virological features of spontaneously-resolving episodes of CMV DNAemia and assessed their impact on mortality through the first year after transplantation. We reviewed the CMV DNA polymerase chain reaction results and clinical charts of 230 consecutive adult patients who underwent T-cell replete allo-HSCT at our center. A total of 280 episodes of CMV DNAemia were registered in 164 patients, of which 144 episodes cleared spontaneously. Clearance of CMV DNAemia was significantly delayed in initial and recurrent self-resolving episodes featuring CMV DNA peak loads > 250 IU/mL compared with those displaying lower values. All-cause mortality in patients with self-resolving episodes of CMV DNAemia was comparable (P = 0.7) to that in patients with no CMV DNAemia and was not related to the CMV DNA peak load (≥250 IU/mL vs <250 IU/mL) (P = 0.6). In summary, in our setting, the magnitude of the CMV DNA peak load reached during self-resolving episodes of CMV DNAemia correlated directly with duration of episodes, but had no apparent impact on all-cause mortality taking patients with no documented CMV DNAemia as a reference. 相似文献
88.
Gideon St.Helen Neal L. Benowitz Jasjit S. Ahluwalia Rachel F. Tyndale Newton Addo Steven E. Gregorich Eliseo J. Pérez-Stable Lisa Sanderson Cox 《Journal of the National Medical Association》2019,111(5):509-520
ObjectiveThe study objective was to identify biobehavioral variables associated with greater intake of nicotine and a tobacco carcinogen among Black light smokers who smoke 1 to 10 cigarettes per day (CPD).MethodsWe analyzed baseline data collected from 426 Black light smokers enrolled in Kick It at Swope III (KIS III), a smoking cessation trial for Black smokers. We examined differences in concentrations of tobacco biomarkers, including urinary total nicotine equivalents (TNE) and total 4-(methylnitrosamino)-1-(3)pyridyl-1-butanonol (NNAL; a human carcinogen), across gender, age, plasma nicotine metabolite ratio (NMR), CPD, and measures of tobacco dependence, including time to first cigarette (TFC), using ANOVA.ResultsTobacco biomarker levels were significantly higher among those who smoked more CPD (6–10 vs 1–5 CPD) and those with greater reported physical dependence on tobacco. Concurrently, those who smoked 1–5 CPD smoked each cigarette more intensely than those who smoked 6–10 CPD. While we found no gender differences overall, among those who smoked 1–5 CPD, women had higher NNAL levels compared to men. The rate of nicotine metabolism, measured by the nicotine metabolite ratio, was not significantly related to TNE or NNAL levels.ConclusionAmong Black Light smokers, higher cigarette consumption and greater physical dependence—but not rate of nicotine metabolism, menthol use, or socioeconomic status—were associated with greater toxicant exposure and thus a likely increased risk of tobacco-related diseases. The lack of data on light smokers, and specifically on Blacks, make this observation important given the disproportionate burden of lung cancer in this population. 相似文献
89.
Vascular endothelial growth factor in exercising humans under different environmental conditions 总被引:7,自引:0,他引:7
Hanns-Christian Gunga Karl Kirsch Lothar Röcker Claus Behn Eberhard Koralewski Eliseo Hibert Davila Manuel Ivan Estrada Bernd Johannes Peter Wittels Wolfgang Jelkmann 《European journal of applied physiology》1999,79(6):484-490
It was the aim of this study to investigate the time course of changes in the serum concentrations of vascular endothelial growth factor (VEGF) during a regular survival training programme combined with food and fluid deprivation and during a high altitude marathon run. We studied soldiers of the Austrian Special Forces performing survival training at sea-level and marathon runners of the Posta Atletica who crossed the border between Chile and Argentina at altitudes up to 4722?m. Baseline data collected before the 1-week of survival training showed that the soldiers had normal VEGF [n=8, 246.7?(SD 118.5)?pg?·?ml?1] serum concentrations which remained unchanged during the course of the study. Before the high altitude marathon the subjects showed normal VEGF serum concentrations [178?(SD 84.5)?pg?·?ml?1]. After the run VEGF concentrations were found to be significantly decreased [41.0?(SD 41.6)?pg?·?ml?1, P?0.01]. It was concluded that prolonged physical stress during normobaric-normoxia did not alter the VEGF concentrations whereas during severe hypobaric-hypoxia decreased VEGF serum concentrations were measured, at least temporarily, after prolonged physical exercise which might have been due to changes in production, release, removal and/or binding of circulating VEGF. 相似文献
90.
Alessandro R. Zanetti Elisabetta Tanzi Luisa Roman Nicola Principi Giovanna Zuin Eliseo Minola Barbara Zapparoli Marina Palmieri Antonio Marini Daniela Ghisotti Paula Friedman Jeffrey Hunt Thomas Laffler 《Journal of medical virology》1998,54(2):107-112
Evidence indicates that the GBV-C or hepatitis G virus can cause persistent infection in humans, but little is known on the importance of vertical transmission. To assess the risk of mother-to-infant transmission and the clinical outcome of infected babies, we investigated 175 anti-HCV positive mothers and followed-up their children for 3–33 months. GBV-C RNA was detected by RT-PCR and anti-E2 antibody was assayed by EIA. Thirty-four (19.4%) women were GBV-C RNA positive and transmission occurred to 21 (61.8%) babies; 20 (95.2%) acquired GBV-C alone, and one (4.8%) GBV-C and HCV. Maternal factors such as intravenous drug use, HIV coinfection, HCV-RNA positivity, and type of feeding were not correlated with GBV-C transmission. GBV-C RNA remained persistently positive in all infected babies but one baby who seroconverted to anti-E2. Seven (35%) babies with GBV-C alone developed marginally elevated ALT; the baby with HCV and GBV-C co-infection had the highest ALT peak value (664 IU/l). Seven of the 141 (5%) babies born to the GBV-C RNA negative mothers acquired HCV and six (85.7%) had abnormal ALT. The mean ALT peak value was significantly higher (P < 0.05) for babies with HCV than for those with GBV- C. None of the children with GBV-C or with HCV became icteric. GBV-C is frequently present in anti-HCV positive women. The infection is transmitted efficiently from mother to baby and rate of transmission is much higher than that for HCV. GBV-C can cause persistent infection in babies but usually without clear evidence of liver disease. J. Med. Virol. 54: 107–112, 1998. © 1998 Wiley-Liss,Inc. 相似文献