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1.
Myocardial infarction (MI) remains the leading cause of death in the western world. Despite advancements in interventional revascularization technologies, many patients are not candidates for them due to comorbidities or lack of local resources. Non-invasive approaches to accelerate revascularization within ischemic tissues through angiogenesis by providing Vascular Endothelial Growth Factor (VEGF) in protein or gene form has been effective in animal models but not in humans likely due to its short half-life and systemic toxicity. Here, we tested the hypothesis that PR1P, a small VEGF binding peptide that we developed, which stabilizes and upregulates endogenous VEGF, could be used to improve outcome from MI in rodents. To test this hypothesis, we induced MI in mice and rats via left coronary artery ligation and then treated animals with every other day intraperitoneal PR1P or scrambled peptide for 14 days. Hemodynamic monitoring and echocardiography in mice and echocardiography in rats at 14 days showed PR1P significantly improved multiple functional markers of heart function, including stroke volume and cardiac output. Furthermore, molecular biology and histological analyses of tissue samples showed that systemic PR1P targeted, stabilized and upregulated endogenous VEGF within ischemic myocardium. We conclude that PR1P is a potential non-invasive candidate therapeutic for MI.  相似文献   
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PURPOSE: To determine the potential of proton MR spectroscopy to monitor patients with childhood-onset cerebral adrenoleukodystrophy (COCALD). METHODS: Single-voxel MR spectroscopy was performed in 16 children with COCALD (24 examinations) who had had no treatment and in 7 children (13 examinations) who had had bone marrow transplantation. RESULTS: In the untreated children with clinically active COCALD, the metabolite ratios N-acetyl-aspartate (NAA)/creatine (Cr) and NAA/choline (Ch) were decreased while Ch/Cr was increased. This trend agrees well with those reported by other researchers, although different experimental sequences and parameters were used in our study. Comparison of these ratios with those from a control group yielded significant differences in the occipital region. In the children who were clinically stable after bone marrow transplantation, the mean levels of the three ratios were between those of the control subjects and the patients with untreated COCALD: the differences in these ratios approached significance. In patients who had been monitored periodically, MR spectroscopy metabolite ratios correlated well with the dementia rating score, reflecting clinical status. CONCLUSION: There is good correlation between MR spectroscopy metabolite ratios and a patient's clinical status. MR spectroscopy appears to be a useful, noninvasive tool to monitor patients with adrenoleukodystrophy, and it increases the overall sensitivity of MR techniques in clinical applications.  相似文献   
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We have studied Pbs21, a major ookinete surface protein of Plasmodium berghei, for the development of a model transmission blocking immunogen. In the mouse, recombinant Pbs21 expressed in the Escherichia coli expression system (EcrPbs21) is not as effective in inducing transmission blocking antibodies as native Pbs21 (nPbs21), possibly because of differences in post-translational processing between EcrPbs21 and nPbs21. In an attempt to improve the efficacy of the recombinant molecule, we describe here the use of a baculovirus expression vector system in the silkworm Bombyx mori. Following an injection of recombinant baculovirus containing Pbs21 cDNA, B. mori larvae produced recombinant Pbs21 (BmrPbs21) with a molecular weight indistinguishable from nPbs21. Fifty micrograms of BmrPbs21 could be purified from the hemolymph of each infected larva using affinity chromatography. Immunization of Balb/c mice with BmrPbs21 induced high anti-BmrPbs21 and anti--ookinete antibodies but low anti-EcrPbs21 antibody. In contrast, EcrPbs21 induced high anti--EcrPbs21 antibody but low anti-BmrPbs21 and anti-ookinete antibodies. This suggests that most B-cell epitopes on nPbs21 are conformational and that many of the linear epitopes in EcrPbs21 are not normally exposed in nPbs21. Oocyst formation in Anopheles stephensi mosquitoes, which fed on mice immunized with purified BmrPbs21 and infected with P. berghei, was blocked by 85.5-97.1%. These results suggest that the baculovirus-silkworm system produces useful quantities of recombinant Pbs21 which in limited studies is structurally and immunogenically indistinguishable from the native molecule.  相似文献   
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Emotional reactions of therapists who experienced the death by suicide of one or more of their patients were investigated. Data were collected by a questionnaire containing both objective and open-ended items from 27 men and 36 women, psychiatrists and psychologists, working in psychiatric hospitals in Slovenia. The most frequently reported reactions by the therapists were of increased caution in the treatment of their patients and an increase in conferring with colleagues, partners, and supervisors. About two thirds reported experiencing strong guilt feelings along with other commonly reported survivor feelings of grief, depression, and loss. Gender differences were apparent (women more often felt shame and guilt, sought consolation, or doubted their professional knowledge). No significant differences appeared between disciplines and years of work experience. Agreement was general that support was important both professionally and personally. Suggestions are offered to help the therapist work through the trauma of a patient's suicide.  相似文献   
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In this study, feature-extraction methods based on principal component analysis, most discriminant features, and regularised-direct linear discriminant analysis (RD-LDA) are tested and compared in an experimental finger-based personal authentication system. The system is multimodal and based on features extracted from eight regions of the hand: four fingerprints (the prints of the finger tips) and four digitprints (the prints of the fingers between the first and third phalanges). All of the regions are extracted from one-shot grey-level images of the palmar surface of four fingers of the right hand. The identification and verification experiments were conducted on a database consisting of 1840 finger images (184 people). The experiments showed that the best results were obtained with the RD-LDA-based feature-extraction method 2 99.98% correct identification for 920 tests and an equal error rate of 0.01% for 64170 verification tests.  相似文献   
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Monostrand Prestressing with unbonded Tendons. Application, Experiences, Advantages, Economic Viability Prestressing of strands with unbonded tendons has proved to be effective in practice without reservation. The additional procedure is not inconsiderable, but should be regarded in its context, since it will be more than compensated for by the convincing advantages like crack‐freeness, low deflection of components, etc., in the long run. The article below discusses recent findings and experiences. Additionally, it deals with expanded fields of application, such as partial prestressing, flat slabs, hollow‐block slabs with long span, and, as a quantum leap, the prestressed flat slab made of steel fibre concrete.  相似文献   
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•  To evaluate global and domestic corporations on their sustainability engagement, numerous metrics have been developed at the national and international levels.  相似文献   
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A female with advanced aortic valvular stenosis and moderate right coronary artery disease experienced an exertional syncope during 24-h ambulatory electrocardiographic monitoring. A progressive bradycardia with 90-s sinus node arrest (cardio-inhibitory response) and premonitory angina pectoris with significant ST segment changes were demonstrated. Our report supports the concept of a neurocardiogenic (vasovagal) mechanism of exertional syncope in patients with aortic stenosis. The predominant left ventricular inferior-wall myocardial ischaemia in our patient might be an additional stimulus to left ventricular mechanoreceptors, resulting in a profound cardio-inhibitory response.  相似文献   
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