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1.
A community outbreak of hepatitis A is described, involving 23 persons in a small town in central Israel. Seventy-four percent of the cases were related to a contact with toddlers in one nursery class in a day care center. There were no overt cases in that class itself. The mode of transmission exemplified in this community underlines the difficulties in identifying a common source of hepatitis A infection, which is necessary for the elimination of a further spread of the disease.  相似文献   
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Digestive Diseases and Sciences - Clostridioides difficile infection (CDI) is caused by Toxins A and B, secreted from pathogenic strains of C. difficle. This infection can vary greatly in symptom...  相似文献   
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BACKGROUND: Despite increasing evidence that beta-hydroxy-beta-methyglutaryl coenzyme A reductase inhibitors reduce the incidence of stroke in patients with coronary heart disease (CHD), the associations between blood lipid levels and cerebrovascular disease (CVD) are not clear. OBJECTIVE: To evaluate whether blood cholesterol level and its fractions are risk factors for stroke in a large group of patients with CHD. METHODS: We followed up 11 177 patients with documented CHD who were screened for but not included in the Bezafibrate Infarction Prevention study, a secondary prevention randomized clinical trial of lipid modification, and had no history of stroke for subsequent CVD. During a 6- to 8-year follow-up period, 941 patients were identified as having nonhemorrhagic CVD, of whom 487 had verified ischemic stroke or transient ischemic attack (TIA). RESULTS: Increases in age-adjusted rates of both nonhemorrhagic CVD and verified ischemic stroke or TIA were identified with increasing cholesterol and low-density lipoprotein cholesterol levels, decreasing high-density lipoprotein cholesterol levels, and decreasing percentage of total serum cholesterol contained in the HDL moiety. In logistic regression models, adjusting for clinical covariates, the following odds ratios (95% confidence intervals) were identified for lipid values in the upper vs lower tertile for the end point of nonhemorrhagic CVD: total cholesterol, 1.43 (1.20-1.70); low-density lipoprotein cholesterol, 1.52 (1.27-1.81), high-density lipoprotein cholesterol, 0.84 (0.70-1.00); and percentage of serum cholesterol contained in HDL, 0.69 (0.58-0.83). Similar trends appeared for the end point of verified ischemic stroke or TIA. CONCLUSION: These findings clearly support the role of total cholesterol and its fractions in prediction of ischemic CVD among patients with established CHD.  相似文献   
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The association between exaggerated blood pressure (BP) response to exercise (ExBPR) and “masked hypertension” is unclear. Medical records of patients with high‐normal BP who were evaluated in the Chaim Sheba Screening Institute Ramat Gan, Israel, during the years 2002–2007 and referred for 24‐hour ambulatory BP monitoring (ABPM) and exercise test were reviewed. Data on exercise tests performed in the preceding 5 years were retrieved. Reproducible ExBPR was defined when it was recorded at least twice. BP levels on 24‐hour ABPM were compared between patients with a normal BP response and those with an ExBPR (systolic BP ≥200 mm Hg). Sixty‐nine normotensive patients with high normal BP levels were identified. ExBPR was recorded in 43 patients and was reproducible in 28. BP levels on 24‐hour ABPM were similar in patients with and without ExBPR. In patients with high‐normal BP levels, ExBPR is not associated with masked hypertension.  相似文献   
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Using morpholino antisense oligonucleotide (MO) technology, we blocked leptin A or leptin receptor expression in embryonic zebrafish, and analyzed consequences of leptin A knock-down on fish development. Embryos injected with leptin A or leptin receptor MOs (leptin A or leptin receptor morphants) had smaller bodies and eyes, undeveloped inner ear, enlarged pericardial cavity, curved body and/or tail and larger yolk compared to control embryos of the same stages. The defects persisted in 6-9days old larvae. We found that blocking leptin A function had little effect on the development of early brain (1day old), but differentiation of both the morphant dorsal brain and retinal cells was severely disrupted in older (2days old) embryos. Despite the enlarged pericardial cavity, differentiation of cardiac cells appeared to be similar to control embryos. Formation of the morphants' inner ear is also severely disrupted, which corroborates existing reports of leptin receptor expression in inner ear of both zebrafish and mammals. Co-injection of leptin A MO and recombinant leptin results in partial rescue of the wild-type phenotype. Our results suggest that leptin A plays distinct roles in zebrafish development.  相似文献   
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Recent theories of metaphor comprehension discuss the cognitive substrates involved in processing metaphors. However, the role of valence perception during metaphor comprehension has received little attention. The present study aims to examine the effect of emotional valence on metaphor processing, as well as the interaction between this effect and hemispheric differences. Metaphoric, literal, and meaningless word pairs were presented to 43 participants who performed a semantic judgment task. Results showed that processing of metaphors with negative valence was faster when done in the right hemisphere as compared with the left hemisphere. These findings indicate that emotional valence interacts with cognitive processes of metaphor comprehension. We discuss valence with respect to the class inclusion model and the fine versus coarse semantic coding model of metaphor processing.  相似文献   
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In this work, we provide an up-to-date summary of the available molecular- and cell-related mechanisms by which alpha1-antitrypsin (AAT) protein could be of benefit in treating COVID-19 patients. As well, we demonstrate the current status in terms of the ongoing clinical trials using AAT in COVID-19 patients. Finally, we touch on the potential role gene therapy and stem cell-based gene therapy could have in such emerging and serious condition caused by the SARS-CoV-2 virus.  相似文献   
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