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排序方式: 共有417条查询结果,搜索用时 15 毫秒
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STUDY OBJECTIVE: To determine the frequency of electrocardiographic (ECG) changes and to assess the occurrence of myocardial ischemia during elective cesarean delivery with either regional or general anesthesia. DESIGN: Randomized, prospective, single-blinded clinical trial. SETTING: Large referral hospital. PATIENTS: 40 ASA physical status I and II term parturients. INTERVENTIONS: Patients were divided randomly into two groups as follows: the regional anesthesia group (group 1, n = 20) and the general anesthesia group (group 2, n = 20). MEASUREMENTS: In each case, continuous ECG was done using a 7-lead Holter monitor in the operating room, continuing for 24 hours after surgery. All Holter traces were analyzed by a study-blinded cardiologist. Blood samples were collected preoperatively (baseline) and at one, 5, and 24 hours postoperatively. Serum troponin T, creatinine kinase-MB, and myoglobin levels were measured. MAIN RESULTS: Two patients in group 1 (10%) and one patient in group 2 (5%) showed one mm ST-segment depression for two to 5 minutes. In all 40 cases, troponin T levels were in the normal range at all time points studied. In both groups, mean serum creatinine kinase-MB and myoglobin levels at one and 5 hours postoperatively were significantly higher than at baseline (P < 0.05). These high CK-MB and myoglobin levels were returned to normal ranges at the end of the study period; none of these women showed ST-segment changes. CONCLUSION: The ST-segment changes are not frequent in healthy women undergoing elective cesarean delivery during either regional or general anesthesia, and we found no evidence of myocardial injury. 相似文献
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Atrial fibrillation (AF) may occur during or after percutaneous coronary interventions (PCI). The purpose of the study was to determine the clinical, angiographic and electrophysiological predictors of AF after PCI. 225 patients undergoing PCI (mean age of 65 +/- 11 years) who had sinus rhythm (SR) before balloon inflation were taken to study. Of these 22 developed AF in catheterization laboratory after balloon inflation or in 24 h following PCI (AF group), 203 did not (SR group). The patients in AF group were older (67 +/- 9 vs. 63 +/- 8 years, p < 0.05) and their ventricular ejection fraction was lower than SR group (56 +/- 5 vs. 45 +/- 7%, p < 0.05). The P-wave dispersion was significantly higher in AF group than SR group (53 +/- 8 vs. 29 +/- 10 ms, p < 0.001). For the patients with ST elevation myocardial infarction, the time from the onset of symptoms to balloon inflation was 3.7 +/- 1.7 h in SR group. It was longer in AF group (4.1 +/- 1.8 h, p < 0.05). TIMI perfusion grades 2 and 3 were achieved in 23 of 27 patients in SR group, and 5 of 8 patients in AF group. Multivessel disease was documented in 93 of the patients in SR group, and 12 in AF group. Clinical reperfusion was thought to be established in 20 in SR group, and 4 in AF group. In conclusion, our results show the importance of clinical factors, angiographic results and P-wave analysis in prediction of AF following PCI. 相似文献
47.
Initial analyses of colon cancer-specific antigen (CCSA)-3 and CCSA-4 as colorectal cancer-associated serum markers 总被引:1,自引:0,他引:1
Leman ES Schoen RE Weissfeld JL Cannon GW Sokoll LJ Chan DW Getzenberg RH 《Cancer research》2007,67(12):5600-5605
Colon cancer-specific antigen (CCSA)-3 and CCSA-4 are novel colon cancer markers identified by focused proteomic analysis of nuclear structural proteins. The goal of these studies was to evaluate serum-based CCSA-3 and CCSA-4 in the detection of individuals with preneoplastic and neoplastic lesions using ELISAs. Serum samples from 107 subjects undergoing colonoscopy, 28 subjects with colorectal cancer, and 125 subjects with benign disease or other types of cancer were evaluated. Individuals who underwent colonoscopy were classified into mutually exclusive categories, including normal colon, hyperplastic polyp, nonadvanced adenoma, and advanced adenoma. Sensitivity and specificity for both CCSA-3 and CCSA-4 were evaluated using receiver operating characteristic (ROC) curves. At a cutoff of 2 microg/mL for CCSA-3 and 0.3 microg/mL for CCSA-4, each marker detected all 28 colorectal cancers, for a sensitivity of 100% (lower 95% confidence bound, 89.8%). The sensitivity for detection of the combined end point of colorectal cancer and advanced adenoma for CCSA-3 was 89.1% [95% confidence interval (95% CI), 76.4-96.4%] and for CCSA-4 was 84.8% (95% CI, 71.1-93.7%) and 91.3% (95% CI, 79.2-97.6%) for either marker positive. The specificity in individuals with normal, hyperplastic polyps, or nonadvanced adenomas was 82.0% (95% CI, 72.4-89.4%) and 91.0% (95% CI, 83.0-96.0%) for CCSA-3 and CCSA-4, respectively. ROC curves for CCSA-3 and CCSA-4 reveal an area under the curve of 0.94 (95% CI, 0.90-0.98%). In these initial analyses, CCSA-3 and CCSA-4 show promise as potential serum markers for detection of colorectal cancer and advanced adenomas. 相似文献
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Rongman Cai Shuangchun Yan Haijie Liu Scotland Leman Boris A. Vinatzer 《Infection, genetics and evolution》2011,11(7):1738-1751
Several lines of evidence suggest that highly virulent bacterial human pathogens evolved from less virulent wider host range animal pathogens since human migration out of Africa. To investigate evolution of host specificity of bacterial plant pathogens, here we report a molecular evolutionary analysis of the model plant pathogen Pseudomonas syringae pv. tomato DC3000 and of close relatives that are pathogens of a diverse set of crop plants. Extensive host range tests on five different plant species were performed. Combining phylogenetic data with host range data, a reconstruction of host range of all putative ancestors was performed. In particular, the hypothesis was tested that highly virulent narrow host range pathogens of today’s crops grown in monoculture evolved from ancestors with wider host range that were adapted to natural mixed plant communities of pre-agricultural times. We found support for this hypothesis in individual clades. However, reconstruction of host range of the most recent common ancestor of all analyzed strains was not conclusive. Based on the obtained results we stress the importance of including pathogens from wild plants when reconstructing the evolution of plant pathogenic bacteria. 相似文献
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Swanepoel R Smit SB Rollin PE Formenty P Leman PA Kemp A Burt FJ Grobbelaar AA Croft J Bausch DG Zeller H Leirs H Braack LE Libande ML Zaki S Nichol ST Ksiazek TG Paweska JT;International Scientific Technical Committee for Marburg Hemorrhagic Fever Control in the Democratic Republic of Congo 《Emerging infectious diseases》2007,13(12):1847-1851
To determine reservoir hosts for Marburg virus (MARV), we examined the fauna of a mine in northeastern Democratic Republic of the Congo. The mine was associated with a protracted outbreak of Marburg hemorrhagic fever during 1998-2000. We found MARV nucleic acid in 12 bats, comprising 3.0%-3.6% of 2 species of insectivorous bat and 1 species of fruit bat. We found antibody to the virus in the serum of 9.7% of 1 of the insectivorous species and in 20.5% of the fruit bat species, but attempts to isolate virus were unsuccessful. 相似文献