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91.
Developmental changes of cardiac repolarization in rabbits: implications for the role of sex hormones 总被引:3,自引:0,他引:3
Valverde ER Biagetti MO Bertran GR Arini PD Bidoggia H Quinteiro RA 《Cardiovascular research》2003,57(3):625-631
OBJECTIVES: Firstly, to compare gender-dependent differences of cardiac repolarization in both adult and young rabbits. Secondly, to analyze the effect of gonadectomy on these gender differences in cardiac repolarization. METHODS: We evaluated potential gender differences in cardiac repolarization with both microelectrode and ECG recordings. QT(end), JT(end), and T(peak-end) intervals and action potential durations at 30%, 50% and 90% of full repolarization were used to assess ventricular repolarization in adult (normal and gonadectomized) and young rabbits of both sexes. RESULTS: Adult rabbits exhibited clear gender-related differences in repolarization evidenced by significantly longer JT(end) and T(peak-end) intervals and significantly longer APD30, APD50 and APD90 in females. These gender-related differences in repolarization were absent in young rabbits and were abolished by gonadectomy. CONCLUSIONS: Developmental changes of repolarization are present in rabbits. These changes are in agreement with those reported in humans and may further support the role played by sex hormones in the modulation of cardiac repolarization. 相似文献
92.
Experimental leptospirosis in marmoset monkeys (Callithrix jacchus): a new model for studies of severe pulmonary leptospirosis 总被引:3,自引:0,他引:3
Pereira MM Da Silva JJ Pinto MA Da Silva MF Machado MP Lenzi HL Marchevsky RS 《The American journal of tropical medicine and hygiene》2005,72(1):13-20
Experimental infection of marmoset monkeys (Callithrix jacchus) with Leptospira interrogans serovar Copenhageni showed microscopic patterns of tissue reactions comparable to those seen in the severe forms of human leptospirosis, including intra-alveolar hemorrhage. The most impressive microscopic changes were seen in the lung and kidney of animals killed at days 6 and 12 after inoculation. There were extensive and irregular areas of hemorrhage predominating around main bronchial branches or diffusely spread to the pulmonary parenchyma, as well as severe tubulointerstitial nephritis. Antibody response detected by the microscopic agglutination test was quantitatively similar to those seen in humans and paralleled severity of tissue lesions. The distribution of leptospires or antigenic debris in infected tissues was observed by immunofluorescence and confocal laser scanning microscopy. Large numbers of typical leptospires were seen in the lumen of proximal renal tubules. Positive reactions showing antigenic debris were closely associated with sites of tissue damage. 相似文献
93.
Rennert G Almog R Tomsho LP Low M Pinchev M Chaiter Y Bonner JD Rennert HS Greenson JK Gruber SB 《Diseases of the colon and rectum》2005,48(12):2317-2321
PURPOSE The probability of colorectal cancer is moderately increased among carriers of the APC I1307K polymorphism. However, it is not known if endoscopic surveillance of this high-risk group is warranted. The prevalence
of polyps and adenomas in specimens of colorectal cancer who are carriers and noncarriers of the APC I1307K polymorphism is compared.
METHOD Prevalence of adenomatous polyps in the pathology specimens of the study participants, stratified by their APC I1307K polymorphism status, was studied in 900 consecutive cases of colorectal cancer diagnosed in northern Israel between
1998 and 2002, within the framework of a population-based, case-controlled study (MECC Study).
RESULTS The APC I1307K mutation was detected in 78 colorectal cancer cases (8.7 percent) of the study population. Prevalence was higher among
Ashkenazi Jews (11.2 percent) than among non-Ashkenazi Jews (2.7 percent) or Arabs (3.1 percent). After adjustment for age,
APC I1307K carriers were significantly more likely than noncarriers to have polyps in their surgical specimen (51.3 percent vs. 32.6 percent, P = 0.002). Adenomas with a tubular component (either tubular adenomas or tubulovillous adenomas), but not villous adenomas,
were significantly more frequent among carriers (37.2 percent vs. 23.6 percent, P = 0.005).
CONCLUSION Together with former evidence of I1307K being a risk factor for colorectal cancer, these data suggest that colonoscopic surveillance
for colorectal adenomas and cancer may be warranted in I1307K carriers, even in the absence of other identifiable risk factors.
Supported by the National Institutes of Health grant RO1-CA81488 to S.B.G. and G.R. 相似文献
94.
Guilherme Silva Torrezan Carlos Roberto Polaquini Marcelo Freitas Lima Luis Octavio Regasini 《Sustainable Chemistry and Pharmacy》2020
Glycerol is the main co-product from biodiesel production and has been recognized as a sustainable solvent. Herein, we used glycerol and waste glycerol in synthesis of two bioactive α,β-unsaturated ketones (E,E)-1,5-diphenylpenta-2,4-dien-1-one (1) and (E,E)-2,6-dibenzylidenecyclohexanone (2), using aldol mono- and di-condensation reactions, respectively. Crude yield values were calculated from product mass after precipitation and drying. Purity was measured by High Performance Liquid Chromatography with Photodiode Array (HPLC-PAD) using analytical curves and reference compounds. Glycerol and waste glycerol were able to furnish 1 and 2 in higher crude yields and HPLC-PAD purities values than other protic solvents (ethanol, methanol, PEG-400 and water). In order to investigate reasons of glycerol efficiency when compared to water efficiency, we performed computational calculations using Density Functional Theory (DFT). Theoretical predictions confirmed the E1cB mechanism, as well as favourable energy barrier using glycerol in comparison to water, corroborating their sustainable properties. In addition, waste glycerol from corn and sunflower oil transesterifications were used in the synthesis of 1 and 2 for four recycles, displaying good crude yields and HPLC-purities. 相似文献
95.
Vasvi Singh Andrew D. Choi Jonathon Leipsic Ayaz Aghayev James P. Earls Philipp Blanke Michael Steigner Leslee J. Shaw Phd Marcelo F. Di Carli Todd C. Villines Ron Blankstein 《Journal of Cardiovascular Computed Tomography》2021,15(1):16-26
The COVID-19 pandemic has affected patient care deliver throughout the world, resulting in a greater emphasis on efficiently and safety. In this article, we discuss the experiences of several North American centers in utilizing cardiac CT during the pandemic. We also provide a case-based overview which highlights the advantages of cardiac CT in evaluating the following scenarios: (1) patients with possible myocardial injury versus myocardial infarction; (2) patients with acute chest pain; (3) patients with stable chest pain; (4) patients with possible intracardiac thrombus; (5) patients with valvular heart disease. For each scenario, we also provide an overview of various societies recommendations which have highlighted the use of cardiac CT during different phases of the COVID-19 pandemic. We hope that the advantages of cardiac CT that have been realized during the pandemic can help promote wider adoption of this technique and improved coverage and payment by payors. 相似文献
96.
Chamberlain Jayne L. Huda Saif Whittam Daniel H. Matiello Marcelo Morgan B. Paul Jacob Anu 《Journal of neurology》2021,268(5):1665-1665
Journal of Neurology - The original version of this article unfortunately contained a mistake. Fifth sentence of the fourth paragraph in the section “Non-nAChR autoantibody targets in... 相似文献
97.
Garg Aayushi Starr Matthew Rocha Marcelo Ortega-Gutierrez Santiago 《Journal of neurology》2021,268(8):3020-3025
Journal of Neurology - The clinical factors predisposing to ischemic stroke in reversible cerebral vasoconstriction syndrome (RCVS) are unclear. In this observational cross-sectional study, we... 相似文献
98.
Marcelo Coelho Goiato Guilherme Sarauza Arsufi Rodrigo Antonio de Medeiros Aldiéris Alves Pesqueira Emily Vivianne Freitas da Silva Mariana Vilela Sonego 《Journal of medical engineering & technology》2013,37(5):359-367
AbstractIn some clinical situations, the clinician may encounter previously installed implants that should be associated with other implants for a proper rehabilitation. The aim of this study was to evaluate the biomechanical behaviour of a multiple prosthesis joined by different implant connections using photoelasticity. Photoelastic models with a screwed fixed prosthesis supported by implants with different connection systems (Morse taper, external hexagon, internal hexagon, and Flexcone), and different combinations among them, were fabricated. Each assembly was placed in a circular polariscope, and axial and oblique (45°) loads of 100 N were applied on the occlusal surface of the crowns. The fringe patterns were photographed and the analysis was performed by counting the number of high-intensity fringes and also according to the stress distribution region where they appeared. Among implants of the same connection, the external connections obtained a greater number of high intensity fringes when compared to the internal connections. From the biomechanical point of view, the association between different types of connections obtained positive results. 相似文献
99.
Mayara Cortez Luciana Simão Carmo Marcelo Macedo Rogero Primavera Borelli Ricardo Ambrósio Fock 《Inflammation》2013,36(2):379-386
It is well established that a high-fat diet (HFD) can lead to overweight and ultimately to obesity, as well as promoting low-grade chronic inflammation associated with increased levels of such mediators as TNF-α, IL-1, and IL-6. Bone marrow mesenchymal stem cells (MSCs), which are involved in hematopoietic niches and microenvironments, can be affected by these cytokines, resulting in induction of NF-κB and inhibition of PPAR-γ. Because this phenomenon could ultimately lead to suppression of bone marrow adipogenesis, we set out to investigate the effect of an HFD on the expression of PPAR-γ and NF-κB, as well as the production of IL-1, IL-6, and TNF-α in MSCs. Two-month-old male Wistar rats were fed a HFD diet and evaluated by means of leukograms and myelograms along with blood total cholesterol, triglyceride, and C-reactive protein levels. MSCs were isolated, and PPAR-γ and NF-κB were quantified, as well as IL-1, IL-6, and TNF-α production. Animals that were fed a HFD showed higher levels of blood total cholesterol, triglycerides, and C-reactive protein with leukocytosis and bone marrow hyperplasia. MSCs from HFD animals showed increased production of IL-1, IL-6, and TNF-α and increased NF-κB and reduced PPAR-γ expression. Therefore, ingestion of an HFD induces alterations in MSCs that may influence modulation of hematopoiesis. 相似文献
100.
Suen Paulo J. C. Doll Sarah Batistuzzo Marcelo C. Busatto Geraldo Razza Lais B. Padberg Frank Mezger Eva Bulubas Lucia Keeser Daniel Deng Zhi-De Brunoni Andre R. 《European archives of psychiatry and clinical neuroscience》2021,271(1):101-110
European Archives of Psychiatry and Clinical Neuroscience - Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation intervention investigated for the treatment of... 相似文献