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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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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8.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
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The primary neutralization epitope of porcine respiratory and reproductive syndrome virus strain VR-2332 is located in the middle of the GP5 ectodomain 总被引:11,自引:0,他引:11
Summary. Pigs infected with porcine respiratory and reproductive syndrome virus (PRRSV) strain VR-2332 were found to generate high
levels of antibodies (Abs) that bound in an indirect ELISA to synthetic peptides representing segments of the primary envelope
glycoprotein (GP5) ectodomain of this virus. Use of overlapping GP5 ectodomain peptides of various length indicated that the
epitope recognized by the Abs was located in the middle of the ectodomain (amino acids 36-52), in the same relative segment
that contains the single linear neutralization epitope of the closely related mouse arterivirus, lactate dehydrogenase-elevating
virus (LDV). The VR-2332 GP5 segment exhibits 77% amino acid homology with the corresponding GP5 ectodomain segments of both
the European PRRSV strain Lelystad virus (LV) and LDV. This explains some observed crossreaction between the pig Abs and neutralizing
anti-LDV monoclonal Abs with peptides representing the GP5 ectodomains of VR-2332, LV and LDV. The GP5 binding Abs of pigs
seem to be the primary PRRSV neutralizing Abs, since the well timed appearance in sera of all VR-2332 infected pigs of GP5
peptide binding Abs correlated 100% with the appearance of neutralizing Abs and earlier studies indicated that GP5 of PRRSV,
like that of other arteriviruses, contains the main neutralization epitope of PRRSV. In addition, one neutralizing anti-LDV
monoclonal Ab that is specific for the GP5 ectodomain epitope of LDV also strongly neutralized both PRRSV strains, VR-2332
and LV. The PRRSV GP5 epitope is associated with an N-glycan that is conserved in both PRRSV genotypes and all LDV isolates.
This N-glycan may impede the humoral immune control of PRRSV in infected pigs and might be responsible for the low immunogenicity
of PRRSV when injected into mice.
Received April 2, 2002; accepted July 9, 2002 相似文献
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Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented. 相似文献