Search results for "specificity"

Sensitive Troponin I Assay in Early Diagnosis of Acute Myocardial Infarction

2009

BACKGROUND Cardiac troponin testing is central to the diagnosis of acute myocardial infarction. We evaluated a sensitive troponin I assay for the early diagnosis and risk stratification of myocardial infarction. METHODS In a multicenter study, we determined levels of troponin I as assessed by a sensitive assay, troponin T, and traditional myocardial necrosis markers in 1818 consecutive patients with suspected acute myocardial infarction, on admission and 3 hours and 6 hours after admission. RESULTS For samples obtained on admission, the diagnostic accuracy was highest with the sensitive troponin I assay (area under the receiver-operating-characteristic curve [AUC], 0.96), as compared with t…

Diagnosis of sclerosing cholangitis in children: blinded, comparative study of magnetic resonance versus endoscopic cholangiography.

2013

Summary Background Magnetic resonance cholangiography (MRC) has been validated as comparable to endoscopic retrograde cholangiography (ERC) for the diagnosis of sclerosing cholangitis (SC) in adult patients. In children, MRC is widely used based mainly on non-comparative studies. Patients and methods ERCs and MRCs of seven children (median age 9, range: 7–20 years) with SC and 17 controls (median age 6, range: 2 months–20 years) with other chronic liver diseases were reviewed in a blinded, random and independent way. All patients underwent both examinations within a 6-months slot. All ERCs and 17 MRCs were performed under general anesthesia. One radiologist evaluated both ERCs and MRCs and …

The use of high-pressure liquid cation-exchange chromatography for determination of the 5-methylcytosine content of DNA.

1976

Acetylcholine overflow from isolated perfused hearts of various species in the absence of cholinesterase inhibition

1977

1. The content of acetylcholine in the tissue and effluent of isolated hearts of various birds and mammals was determined in the absence of inhibition of cholinesterase. 2. Stimulation of both vagus nerves for 15 min at 20 Hz caused marked negative chronotropic effects in all species. Spontaneous or stimulation-induced overflow of acetylcholine into the effluents was not detected in mammals. In the avian heart, the order of spontaneous overflow was: duck = chicken > pigeon, whereas the order of evoked overflow was: chicken > pigeon > duck. The acetylcholine overflow from the cat heart was below the limit of estimation (3 pmol g−1 min−1). In the chicken heart, the evoked overflow per min (28…

Regiospecific oxidation of polycyclic aromatic dihydrodiols by rat liver dihydrodiol dehydrogenase

1991

Rat liver dihydrodiol dehydrogenase (DDH, E.C. 1.3.1.20) has recently been shown to oxidize the highly carcinogenic benz[a]anthracene-3,4- dihydrodiol in an NADP(+)-dependent reaction to its corresponding catechol. The present study is a systematic investigation of the substrate specificity of the purified enzyme towards synthetic trans-dihydrodiol metabolites of phenanthrene, benz[a]anthracene, chrysene, dibenz[a, h]anthracene and benzo[a]pyrene. DDH exhibited a remarkable regiospecificity of enzymatic catalysis with regard to the site of the dihydrodiol moiety of the parent hydrocarbon. M-region- and, with lower efficiency, bay-region dihydrodiols were found to be good substrates of the e…

Analgesic and thermic effects, and cerebrospinal fluid and plasma pharmacokinetics, of intracerebroventricularly administered morphine in normal and …

1998

Abstract The relationship between asthma and opioids has barely been investigated. This study examines whether active sensitization of rats changes the analgesic and thermic effects of intracerebroventricular morphine or the pharmacokinetics of the drug. Morphine (5, 10 and 20 μg) was given intracerebroventricularly to sensitized (active immunization to ovalbumin and Al(OH)3 then airway challenge with ovalbumin after 12 days) and normal (i.e. non-sensitized) male Sprague-Dawley rats. The tail-flick latencies and changes in colon temperature were determined before morphine injection and at 30 min intervals for a period of 300 min afterwards. Results were expressed as the area under the time-…

Blue-light imaging compared with high-definition white light for real-time histology prediction of colorectal polyps less than 1 centimeter: a prospe…

2019

Blue-light imaging (BLI) is a new chromoendoscopy technique, potentially useful for differentiating neoplastic from nonneoplastic lesions. The present study was aimed at comparing BLI with high-definition white light (HDWL) in the real-time histology prediction of colon polyps 10 mm.Consecutive outpatients undergoing colonoscopy with the ELUXEO 7000 endoscopy platform and 760 series video colonoscopes (Fujifilm Co, Tokyo, Japan) who had at least 1 polyp 10 mm were randomized to BLI or HDWL for polyp characterization. The accuracy of high-confidence real-time histology prediction (adenoma vs not adenoma) by either BLI or HDWL for polyps 10 mm (primary end-point) and diminutive (≤5 mm) polyps…

In Vivo Strain Analysis of Dilated Ascending Thoracic Aorta by ECG-Gated CT Angiographic Imaging

2017

Accurate assessment of aortic extensibility is a requisite first step for elucidating the pathophysiology of an ascending thoracic aortic aneurysm (ATAA). This study aimed to develop a framework for the in vivo evaluation of the full-field distribution of the aortic wall strain by imaging analysis of electrocardiographic- (ECG) gated thoracic data of 34 patients with ATAA. Seven healthy controls (i.e., non-aneurysmal aorta) from patients who underwent ECG-gated CT angiography for coronary artery diseases were included for comparison. To evaluate the systolic function, ECG-gated computed tomography (CT) angiography was used to generate patient-specific geometric meshes of the ascending aorta…

A supervised learning framework of statistical shape and probability priors for automatic prostate segmentation in ultrasound images

2013

Prostate segmentation aids in prostate volume estimation, multi-modal image registration, and to create patient specific anatomical models for surgical planning and image guided biopsies. However, manual segmentation is time consuming and suffers from inter-and intra-observer variabilities. Low contrast images of trans rectal ultrasound and presence of imaging artifacts like speckle, micro-calcifications, and shadow regions hinder computer aided automatic or semi-automatic prostate segmentation. In this paper, we propose a prostate segmentation approach based on building multiple mean parametric models derived from principal component analysis of shape and posterior probabilities in a multi…

Superior labrum and labral-bicipital complex: MR imaging with pathologic-anatomic and histologic correlation.

1998

The purpose of this study was to analyze the anatomic relationship between the superior labrum, the superior glenoid rim, the superior glenohumeral ligament, and the long head of the biceps tendon.Seventeen cadaveric shoulder specimens underwent axial, oblique coronal, and oblique sagittal MR imaging on a 1.5-T imager. Unenhanced proton density- and T2-weighted spin-echo images with and without fat suppression, and T1-weighted fat-suppressed spin-echo images after intraarticular injection of gadolinium, were obtained of each specimen. The shoulders were then frozen and sectioned into 4-mm-thick slices, either transversely or oblique coronally. After gross anatomic correlation, histologic an…