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International Journal of Mental Health and Addiction - The presence of COVID-19 has had psychological consequences among health personnel; these include fear, anxiety, and depression. In the...  相似文献   
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Leishmania (Viannia) braziliensis, a protozoan parasite widespread in the New World, is responsible for the infection of different mammal orders, including humans. This species is considered to be a major etiological agent of American cutaneous leishmaniasis. A proteomic study was carried out to identify proteins expressed by L. (V.) braziliensis. One hundred and one spots representing 75 protein entries were identified by MALDI-TOF-TOF. Isoelectric point values estimated by gel electrophoresis matched closely with predicted values, although some discrepancies existed suggesting that post-translational protein modifications may be common in L. braziliensis. Moreover, 20 hypothetical proteins were experimentally identified. Identified proteins were classified into 15 groups according to biological process. Among the proteins identified, approximately 40% have not been previously reported in a proteomic map of Leishmania. In addition, a number of potential virulence factors and drug targets were identified in this protein map, including some proteins associated with the metastatic phenotype. This study describes the first compilation of a proteomic reference map for L. braziliensis (pI 4-7, M(r) 10-130 kDa) and provides a very useful tool for comparative studies of strains isolated from patients presenting different clinical manifestations of leishmaniasis as well as a potential tool to identify markers for clinical diagnosis, therapeutics, and prognosis.  相似文献   
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OBJECTIVES: To identify an accurate and reproducible method to define myocardial infarct (MI) size, we conducted a study in a closed-chest canine model of acute myocardial infarction, in which MI size was measured using different thresholding techniques and by imaging at different delay times after contrast administration. BACKGROUND: The MI size by contrast-enhanced magnetic resonance imaging (CE-MRI) is directly related to long-term prognosis. However, previous measurements were done using nonuniform methods and tended to overestimate nonviable areas. METHODS: Thirteen animals underwent 90 min of coronary artery occlusion, followed by reperfusion. The CE-MRI data were acquired within 24 h after reperfusion and compared with triphenyltetrazolium chloride pathology. In the first nine animals, images were obtained approximately 15 min after gadolinium diethylene triamine penta-acetic acid (Gd-DTPA) using an inversion-recovery gradient-echo pulse sequence. To identify the most accurate method, MI size by CE-MRI was measured visually and by semi-automatic thresholding techniques, using different criteria. In four additional animals, images were acquired every 6 min until 30 min after Gd-DTPA. RESULTS: Postmortem MI size was 13.5 +/- 2.6% of left ventricular volume. Semi-automatic techniques, using full-width at half-maximum (FWHM) criterion, correlated best with postmortem data (r(2) = 0.94, p < 0.001; results confirmed by Bland-Altman plots). Using FWHM, there was no difference in MI size between different delay times after contrast (15.2 +/- 2.9% to 14.5 +/- 4.2% at 6 and 30 min, respectively; p = NS). CONCLUSIONS: When an objective technique is used to define MI size by CE-MRI, accurate infarct size measurements can be obtained from images obtained up to 30 min after contrast administration.  相似文献   
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Intracranial haemorrhages are rare but potentially life-threatening complications of spine surgery. Most reported cases involved subdural or cerebellar haemorrhages; supratentorial parenchymal bleeding is very uncommon. We report a 28-year-old woman who underwent resection of a thoracic Ewing''s sarcoma, and developed fatal haemorrhages around her cerebral metastases during surgery. The clinical presentations, possible pathogenesis and potential preventive measures are discussed. Patients with disseminated metastases within the neural axis are at risks of intracranial complications during spine surgery. The presence of intracranial mass lesions should be considered as a relative contraindication to intradural spine surgery.  相似文献   
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Pharmaceutical Chemistry Journal - Azines or di-imines are compounds containing R1R2C=N-N=CR3R4 fragment in its structure. These compounds have received special attention due to their importance as...  相似文献   
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