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INTRODUCTION AND OBJECTIVES: The goal of this study was to analyze the value of electrocardiography in predicting the site of the lesion in the left anterior descending coronary artery, in relation to the first septal and the first diagonal branches, in patients with acute anterior myocardial infarction. METHOD: Ninety consecutive patients who were admitted to the coronary unit with acute anterior myocardial infarction from July 1998 to May 2000 were studied retrospectively. The electrocardiographic changes were analyzed and correlated with the site of the lesion in the anterior descending artery, as determined by coronary angiography. RESULTS: The most useful parameters in predicting the site of the lesion in the left anterior descending coronary artery in acute anterior myocardial infarction are: 1) For lesions proximal to the first septal branch, ST-segment elevation in aVR (p < 0.001) and the absence of Q wave in V4-V6 (p = 0.01). 2) For lesions proximal to the first diagonal branch, abnormal Q wave in aVL (p = 0.01) and ST depression in III (p = 0.05). 3) For lesions proximal to both the first septal and first diagonal branches, ST elevation in aVR (p < 0.001), abnormal Q wave in aVL (p = 0.02), and absence of Q wave in V4-V6 (p = 0.01). 4) For lesions distal to both the first septal and first diagonal branches, abnormal Q wave in V4-V6 (p = 0.001) and absence of ST depression in III (p < 0.001). CONCLUSIONS: In acute anterior myocardial infarction, electrocardiography is useful for predicting the site of the lesion in the left anterior descending coronary artery in relation to the first septal and the first diagonal branches.  相似文献   
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The coronavirus disease 2019 (COVID-19) has amazed by its distinct forms of presentation and severity.COVID-19 patients can develop large-scale ischemic strokes in previously healthy patients without risk factors, especially in patients who develop an acute respiratory distress syndrome (SARS-CoV-2).We hypothesize that ischemic events are usually the result of the combined process of a pro-inflammatory and pro-coagulant state plus vascular endothelial dysfunction probably potentiated by hypoxia, hemodynamic instability, and immobilization, as reported in other cases.To the best of our knowledge, we report the first case of partial obstruction of a vertebral artery in a patient with COVID-19.Decompressive surgery remains a life-saving maneuver in these patients (as in other non-COVID-19 strokes) and requires further investigation.  相似文献   
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Autosomal dominant leukodystrophy (ADLD) is an adult onset demyelinating disorder that is caused by duplications of the lamin B1 (LMNB1) gene. However, as only a few cases have been analyzed in detail, the mechanisms underlying LMNB1 duplications are unclear. We report the detailed molecular analysis of the largest collection of ADLD families studied, to date. We have identified the minimal duplicated region necessary for the disease, defined all the duplication junctions at the nucleotide level and identified the first inverted LMNB1 duplication. We have demonstrated that the duplications are not recurrent; patients with identical duplications share the same haplotype, likely inherited from a common founder and that the duplications originated from intrachromosomal events. The duplication junction sequences indicated that nonhomologous end joining or replication‐based mechanisms such fork stalling and template switching or microhomology‐mediated break induced repair are likely to be involved. LMNB1 expression was increased in patients’ fibroblasts both at mRNA and protein levels and the three LMNB1 alleles in ADLD patients show equal expression, suggesting that regulatory regions are maintained within the rearranged segment. These results have allowed us to elucidate duplication mechanisms and provide insights into allele‐specific LMNB1 expression levels.  相似文献   
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[Purpose] To evaluate pre-extubation variables and check the discriminative validity of age as well as its correlation with weaning failure in elderly patients. [Subjects and Methods] Two hundred thirty-nine consecutive patients (48% female) who were on mechanical ventilation and had undergone orotracheal intubation were divided into four subgroups according to their age: <59 years, 60–69 years, 70–79 years, and >80 years old. The expiratory volume (VE), respiratory frequency (f), tidal volume (VT), and respiratory frequency/tidal volume ratio (f/VT) were used to examine differences in weaning parameters between the four subgroups, and age was correlated with weaning failure. [Results] The rate of weaning failure was 27.8% in patients aged >80 years and 22.1% in patients aged <60 years old. Elderly patients presented higher f/VT and f values and lower VT values. The areas under the receiver operating characteristic curves for f/VT ratio were smaller than those published previously. [Conclusion] Our results indicate that aging influences weaning criteria without causing an increase in weaning failure.Key words: Weaning, Mechanical ventilation, Aging  相似文献   
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Background

The optimal surgical management of patients found to have unresectable pancreatic cancer at open exploration remains unknown.

Methods

Records of patients who underwent non-therapeutic laparotomy for pancreatic cancer during 2000–2009 and were followed until death at Memorial Sloan–Kettering Cancer Center, New York, were reviewed.

Results

Over the 10-year study period, 157 patients underwent non-therapeutic laparotomy. Laparotomy alone was performed in 21% of patients; duodenal bypass, biliary bypass and double bypass were performed in 11%, 30% and 38% of patients, respectively. Complications occurred in 44 (28%) patients. Three (2%) patients died perioperatively. Postoperative interventions were required in 72 (46%) patients following exploration. The median number of inpatient days prior to death was 16 (interquartile range: 8–32 days). Proportions of patients requiring interventions were similar regardless of the procedure performed at the initial operation, as were the total number of inpatient days prior to death. Patients undergoing gastrojejunostomy required fewer postoperative duodenal stents and those undergoing operative biliary drainage required fewer postoperative biliary stents.

Conclusions

In this study, duodenal, biliary and double bypasses in unresectable patients were not associated with fewer invasive procedures following non-therapeutic laparotomy and did not appear to reduce the total number of inpatient hospital days prior to death. Continued effort to identify unresectability prior to operation is justified.  相似文献   
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