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961.
This protocol paper describes the development of an international collaboration to survey several thousand adults from different countries around the world about their sleep during the coronavirus disease 2019 (COVID‐19) pandemic. It is based on the development of a harmonised survey with 50 questions (106 different items) on sleep habits and sleep symptoms that permit comparability of information. The harmonised questionnaire may be used in anonymous cross‐sectional surveys, and the instruments within the questionnaire may also be used in prospective studies and clinical studies. The aim was to develop a questionnaire to sample a variety of sleep–wake disorders and other symptoms likely to be caused by prolonged social confinement or by having had COVID‐19. The questionnaire was designed to be: (a) simple and, (b) free to use, for research purposes, (c) multilingual, and (d) comprehensive. It can be completed in <30 min. By the end of June 2020, the survey questionnaire had been administered in Austria, Canada, China, Finland, France, Germany, Hong Kong, Italy, Japan, Norway, Poland, Sweden, UK and USA. Research questions to be addressed by the pooled data derived from the participating sites focus on describing the nature and rates of various sleep and circadian rhythms symptoms, as well as their psychological and medical correlates, that arise at various points during the COVID‐19 pandemic.  相似文献   
962.
963.
964.
Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. The tumors characteristically harbor KIT or PDGFRA mutations, and mutant tumors respond to imatinib mesylate (Glivectrade mark). Chromosomal imbalances resulting in altered gene dosage are known to have a role in the molecular pathogenesis of these tumors, but the target genes remain to be identified. The present study aimed to identify some of these genes. In total, 35 GIST samples were screened for chromosomal imbalances by array-based comparative genomic hybridization. A cDNA array was used to define the minimal common overlapping areas of DNA copy number change. Eight confirmative, replicate hybridizations were performed using an oligonucleotide array. The most recurrent copy number losses were localized to 14q, 22q, and 1p. Gains were less common with 8q being the most recurrent. Two recurrent deleted regions of 14q were 14q11.2 harboring the PARP2, APEX1, and NDRG2 genes and 14q32.33 harboring SIVA. Additional target candidates were NF2 at chromosome 22, CDKN2A/2B at 9p, and ENO1 at 1p for copy number losses, and MYC at 8q for copy number gains. Array CGH proved to be an effective tool for the identification of chromosome regions involved in the development and progression of GISTs.  相似文献   
965.

Background

Acute left circumflex coronary artery (LCx) occlusion is not easily detected by the standard 12-lead electrocardiogram (ECG).

Methods

In 16 patients continuous ECG recording was performed during balloon occlusion. The treated lesions were divided into proximal and distal based on the location of the ischemic segments with respect to the left obtuse margin of the heart.

Results

Mean ΔST (=ST amplitude during inflation - pre-inflation ST) ≥0.5 mm in both leads I and aVL predicted a proximal occlusion site with sensitivity of 62.5% (95% confidence interval [CI] 24.9–91.5%), specificity 100% (95% CI 63.1–100%), positive predictive value 100% (95% CI 47.8–100%), and negative predictive value 72.7% (95% CI 39–94%). In lead III, mean ΔST was +0.3 mm in the distal and ?0.2 mm in the proximal group, respectively (p = 0.036).

Conclusions

ST elevation in leads I and aVL is associated with myocardial ischemia at or proximal to the left obtuse margin.  相似文献   
966.
Multidirectional M-mode echocardiography (echo) was used to investigate functional and structural changes of the heart in 68 consecutive patients with acute or subacute infectious myocarditis. Forty patients had mild myocardial involvement evident by gradually changing ST-segment or T-wave alterations (not responsive to β blockade) in serial ECGs; 21 patients also had loud S3 gallop and palpable paradoxical cardiac pulsations, and 7 patients had severe congestive heart failure.Echo revealed regional changes in the left ventricular (LV) contraction in all patients with acute myocarditis. The site and size of the asynergic wall motion abnormalities correlated with both the clinical severity of the disease and the location of the T-wave inversions in the ECG. In mild myocarditis hypokinesia only was noted in 1 to 3 sites (mean 2.3) of 11 recorded LV sites (21%). In moderate myocarditis, the local asynergic change was mainly akinesia and more widespread, being surrounded by hypokinetic regions (3.8 of 11 sites, 35 % of the LV sites). In congestive heart failure, the hypokinetic or akinetic segments affected almost the entire left ventricle (7.6 of 11 sites, 69% of the LV sites) (p < 0.001 between the groups). In the last group, all patients had strong “fibrotic” echoes, in contrast to mild myocarditis (13%). In mild infectious myocarditis the contraction disturbance of the asynergic regions also generated a peculiar “quivering” pattern with thin echo lines. In the uninvolved segments, hyperkinesia was observed in most patients. The LV end-diastolic diameters in the 3 groups were 51 ± 5, 58 ± 4 and 65 ± 5 mm (p < 0.05), respectively. Thus, M-mode echo may provide a sensitive technique for detecting LV involvement in acute myocarditis and following its course.  相似文献   
967.
Objective. To assess the aetiology, prognosis and prevalence of spontaneous bacterial peritonitis (SBP) in patients hospitalized for ascites. The validity of an elevated (>11 g/l) serum-ascites albumin gradient (SAAG) in the diagnostic work-up was evaluated. Mortality trends were observed over two periods of time. Material and methods. A total of 231 consecutive patients who underwent diagnostic paracentesis between February 1994 and December 1998 and January 2005 and March 2007 were included in the study. The definition of SBP comprised polymorphonuclear cell count >250/mm3 without evidence of other intra-abdominal source of infection. SAAG was obtained and the Child-Pugh classification applied. Survival rates were obtained from medical records. Results. The most common causes of ascites were alcohol liver cirrhosis (n=143; 62%), malignancy (n=30; 13%), non-alcoholic cirrhosis (n=11; 5%) and malignancy with cirrhosis (n=11; 5%). The prevalence of SBP in cirrhosis was 6.7% (95% CI 2.8–10.5%). Overall mortality rates at 1 month, 6 months and 1 year were 22%, 40% and 48%, respectively, and remained unchanged between the intervals. Patients with grade C liver disease had higher 1-month (26% versus 6%), and 6-month (44% versus 27%) mortality rates than grade B patients, but commensurate 1-year mortality (49% versus 47%). SAAG was ≥11 g/l in 85% of patients with obvious portal hypertension and in 30% with malignancy, ascites albumin level ≤9 g/l in 69% and 20%, respectively. Conclusions. Mortality in patients with ascites was high. The occurrence of SBP was relatively low in our series, with a high proportion of alcoholic cirrhosis. SAAG was inaccurate in differentiating ascites caused by portal hypertension or malignancy.  相似文献   
968.
BACKGROUND: Whether the typical electrocardiographic (ECG) strain pattern (Strain, in leads V5 and/or V6), which is associated with left ventricular hypertrophy (LVH) and LV systolic dysfunction, is independently associated with LV diastolic dysfunction is unknown. METHODS: The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study enrolled hypertensive patients with ECG-LVH, of whom 10% underwent Doppler echocardiography. LV diastolic function measures included peak mitral E and A wave velocities and their ratio (E/A); E wave deceleration time (EDT); atrial filling fraction (AFF); and isovolumic relaxation time (IVRT). Normal filling pattern was defined by E/A < 1 with EDT >or= 150 and or=60 ms; abnormal relaxation by E/A < 1 with EDT > 250 ms or IVRT > 100 ms; pseudonormal filling pattern by E/A >or= 1 associated with IVRT > 100 ms or EDT > 250 ms; restrictive pattern by E/A >or= 1 with IVRT < 100 ms and EDT < 250 ms. A combined index of LV systolic-diastolic function was also computed (isovolumic time/ejection time, modified myocardial performance index). Of LIFE echo substudy participants with all needed ECG and Doppler data (n = 791), 110 (14%) had Strain. RESULTS: Strain was associated with male gender, African-American race, diabetes, history of coronary heart disease (CHD), higher systolic blood pressure (BP), LV mass and relative wall thickness, and higher prevalences of echo-LV hypertrophy and wall motion abnormalities, and with slower heart rate (all P < 0.05). Age, diastolic BP and LV ejection fraction were similar in patients with or without Strain. Diastolic parameters, and prevalences of different LV filling patterns, did not differ significantly between patients with versus those without Strain (all P > 0.1), but modified myocardial performance index was higher with Strain (P < 0.05). Findings were consistent in multivariate analyses. The association of Strain with higher modified myocardial performance index was no longer statistically significant after accounting for LV systolic function and wall motion abnormalities. CONCLUSIONS: In hypertensive patients with ECG-LVH, the ECG Strain pattern did not identify independently those with more severe LV diastolic abnormalities.  相似文献   
969.
970.
AimsThus far, the prognostic value of reverse left ventricular (LV) remodeling after ST-elevation acute myocardial infarction (STEMI) has not been fully evaluated. We sought to investigate the incidence, major determinants, and long-term clinical significance of reverse LV remodeling in a large series of STEMI patients successfully treated with primary percutaneous coronary intervention (P-PCI).Methods and resultsSerial complete 2D-echocardiograms were obtained within 24 h after P-PCI, and at 1 and 6 months in 512 consecutive reperfused STEMI patients. Reverse remodeling was defined as a reduction >10% in LV end-systolic volume (LVESV) at 6 month follow-up. Reverse LV remodeling occurred in 49% of study population. At follow-up (41.6 ± 23 months), late heart failure (HF) rate was significantly higher among patients without reverse LV remodeling as compared with those with it (32% vs. 11%, P < 0.0001). At multivariate analysis, independent predictors of reverse LV remodeling were a small infarct size measured as peak creatine kinase value (P < 0.0001), a small functional myocardial damage measured as wall motion score index within the infarct zone (P = 0.018) and baseline LVESV (P < 0.0001). After adjustment for several clinical, echographic and angiographic variables, Cox analysis identified reverse LV remodeling as the only beneficial independent predictor of long-term heart failure-free survival (HR: 0.44, 95% CI: 0.275–0.722).ConclusionsReverse LV remodeling occurred in half of successfully reperfused STEMI patients. Small structural and functional myocardial damages within the infarct zone are the major determinants of reverse LV remodeling. As expression of effective myocardial salvage by P-PCI, the reverse remodeling is an important predictor of favorable long-term outcome.  相似文献   
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