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Grant P 《Contemporary pediatrics》1994,11(11):84-6, 89-90, 93
Want to practice better medicine, insure third-party reimbursement, and help educate residents in primary care? A standardized encounter form can do all this, and more. Here's how. 相似文献
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Grant EG Duerinckx AJ El Saden S Melany ML Hathout G Zimmerman P Cohen SN Singh R Baker JD 《AJR. American journal of roentgenology》1999,172(4):1123-1129
OBJECTIVE: A wide range of Doppler threshold values for carotid stenosis is found in the literature. We undertook this study to compare methods of derivation and to determine if an optimum strategy of threshold selection exists for a high-risk population. MATERIALS AND METHODS: From the sonograms of all patent internal carotid arteries, peak systolic velocity in the internal carotid artery (ICA(PSV)) and the ratio of peak systolic velocity in the internal carotid artery to that of the common carotid artery (ICA(PSV)/ CCA(PSV)) were compared with the percentage of angiographically determined stenosis. Receiver operating characteristic curves were generated for levels of stenosis > or =60% and > or =70%. Doppler thresholds were chosen on the basis of maximum accuracy and on the basis of > or =90% sensitivity and specificity. Patients were then segregated into symptomatic and asymptomatic cohorts, and the above process was repeated. An effectiveness analysis was also conducted using various Doppler thresholds. Thresholds derived using these three methods were compared and optimal values chosen. RESULTS. Of 333 carotid arteries that fit inclusion criteria, 132 were found in asymptomatic patients and 201 in symptomatic patients. Maximum accuracy, > or =90% sensitivity and specificity, and effectiveness analysis each produced different ranges of thresholds. We chose final thresholds that maintained patient outcome profiles. For asymptomatic patients at the > or =60% stenosis level, thresholds were ICA(PSV) = 200 cm/sec and ICA(PSV)/CCA(PSV) = 3.0. For symptomatic patients with stenosis > or =70%, thresholds were ICA(PSV) = 175 cm/sec and ICA(PSV)/CCA(PSV) = 2.5. CONCLUSION: Considerable latitude exists in the choice of carotid Doppler thresholds. We propose a rational strategy for threshold selection based on a combination of three commonly used methods. Our observations indicate that it appears advisable to consider symptomatic and asymptomatic patients separately and to apply appropriately derived thresholds. 相似文献
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Activated blood coagulation factor XIII has an important role in the final stage of the clotting cascade by the covalent crosslinking of alpha- and gamma-fibrin chains. We have recently shown that a functional polymorphism in exon 2. codon 34 of the FXIII A-subunit gene is protective against myocardial infarction. To investigate the prevalence of three other common point mutations in the A-subunit gene (codon 564, C to T, 650 G to A and 651 G to C) and their association with FXIII activity and antigen levels, 275 patients with coronary artery disease and 196 controls were studied. There was no difference in the prevalence of the polymorphisms between patients and controls or between patients with or without MI. Only genotype at codon 564 was associated with FXIII activity with lower activities in subjects possessing the T allele. There was evidence of linkage disequilibrium between codon 34 and codon 564. These results suggest that FXIIIVal34Leu is the only common polymorphism in the coding region of the A-subunit gene of FXIII associated with coronary artery disease. 相似文献