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The first 150 words of the full text of this article appear below. Key points Coronary artery disease accounts for >30% ofdeaths in Western society. The diagnosis of myocardial infarctionshould be qualified by size, causation and time from occurrence. Mortalityis reduced by immediate or primary percutaneouscoronary intervention or thrombolysis within the first 24 hof onset of ST-segment elevation myocardial infarction. Strategiesto reduce platelet activation (glycoprotein IIb/IIIa receptorantagonists, or clopidogrel) are now recommended in the treatmentof high-risk non-ST-segment myocardial infarction/unstable angina. Elevatedserum troponins may be the result of non-ischaemic myocardialdamage, especially in critical illness.
Pathophysiology
Changes in the definition of terms relating to the diagnosisof myocardial infarction (MI) have evolved by better understandingof the pathophysiology culminating in the new term of acutecoronary syndrome (ACS). Figure 1 illustrates the processesthat occur in the development of an acute coronary event. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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Comparison of the nitration of polyfluoronitrobenzenes by nitronium salts in superacidic and aprotic media: activation of the nitronium ion by protosolvation 下载免费PDF全文
Olah GA Laali KK Sandford G 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(15):6670-6672
The reactivity of nitronium tetrafluoroborate in the nitration of deactivated di- and trifluoronitrobenzenes is enhanced in superacidic trifluoromethanesulfonic (triflic) acid compared with aprotic methylene chloride and sulfolane solutions. The enhanced reactivity is discussed in terms of better solubility and higher dissociation of the nitronium salts, as well as protosolvation of NO2+ by superacids. 相似文献
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I?Satish?RaoEmail author Anand?C?Loya KS?Ratnakar VR?Srinivasan 《BMC clinical pathology》2005,5(1):11
Background
Lymph node infarction is known to occur in association with many non-neoplastic and neoplastic conditions however its occurrence in association with DIC is not reported hitherto in the literature. 相似文献9.
Cytogenetic analyses of three papillary carcinomas and a follicular adenoma of the thyroid 总被引:2,自引:0,他引:2
E Olah E Balogh F Bojan F Juhasz V Stenszky N R Farid 《Cancer Genetics and Cytogenetics》1990,44(1):119-129
Cytogenetic data of three papillary carcinomas and a follicular adenoma using direct preparations or cell cultures or both after 7 to 60 days in vitro are presented. Although karyotype of the follicular adenoma proved completely normal, in each of the three papillary carcinomas a modal chromosome number in the diploid range and a deleted 11q were observed. In case 1 the del(11)(q23) was associated with rearrangement of chromosome 1 and other marker chromosomes. Our results suggest that 11q deletion may be specific for papillary carcinoma of the thyroid. 相似文献
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Embryonic and posthatched differentiation of bursal secretory dendritic cells, which express vimentin intermediate filaments, were studied with anti-vimentin (clone 3B4) and anti-cytokeratin (clone Lu5) monoclonal antibodies. Anti-cytokeratin staining revealed that medullary reticular epithelial cells formed a continuous network at every age, whereas the vimentin positive cells were single and showed dendritic appearance. On the basis of location, number, shape, polarized appearance, and Ia staining, the vimentin-positive cells and secretory dendritic cells appeared to be the same cell. Secretory dendritic cell precursors entered the bursal epithelium between 11 and 13 days of embryogenesis. The first vimentin positive cell appeared in the bud of 14-day embryos. Bud formation preceded the appearance of vimentin-positive cells. These observations suggested that the secretory dendritic cell precursor did not express vimentin when it entered the epithelium. Between 15 days of embryogenesis and 2 weeks of posthatch development, the changes in vimentin staining pattern revealed a cytological differentiation of the vimentin-positive cell. During rapid bursal growth, the number of secretory dendritic cells (vimentin-positive cells) increased about 18 times possibly by proliferation of vimentin-negative precursors in the epithelial arches of the corticomedullary border. © 1992 Wiley-Liss, Inc. 相似文献