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11.
J.F. Cavalini V.D. Aiello P. Guedes de Souza I.V. Trevisan M.B. Marcial M. Ebaid 《Pediatric cardiology》1998,19(6):490-494
Two cases of double outlet right ventricle with restrictive ventricular septal defect are described. This is an uncommon
presentation that causes left ventricular dysfunction because of left ventricular outflow tract obstruction. The presence
of an intact atrial septum leads to severe pulmonary hypertension, which tends to aggravate the right ventricular output.
In the presence of a normal left ventricle, the authors suggest the possibility of enlargement of the ventricular septal defect
in order to perform a biventricular repair. The association of a supramitral valve ring in both cases, and the isolation of
the left subclavian artery and an aortopulmonary fenestration in one of these cases, are also discussed. In addition we explore
factors that cause restrictive ventricular septal defects as well as the mechanisms that may lead to spontaneous closure of
ventricular septal defect in a double outlet right ventricle. 相似文献
12.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
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Eline Lima Borges Gilmara Lopes Amorim Marina Barcelos de Miranda Flaviano dos Santos Martins Antnio Carlos Martins Guedes Kinulpe Honorato Sampaio Josimare Aparecida Otoni Spira Lucíola da Silva Barcelos 《Acta cirúrgica brasileira / Sociedade Brasileira para Desenvolvimento Pesquisa em Cirurgia》2022,37(3)
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Bruno Guedes Baldi Alexandre Todorovic Fabro Andreia Craveiro Franco Marília Helena C Machado Robson Aparecido Prudente Estefnia Thom Franco Sergio Ribeiro Marrone Simone Alves do Vale Talita Jacon Cezare Marcelo Padovani de Toledo Moraes Eloara Vieira Machado Ferreira Andr Luis Pereira Albuquerque Marcio Valente Yamada Sawamura Suzana Erico Tanni 《Jornal brasileiro de pneumologia》2022,48(3)
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Ana Paula Rocha-de-Melo Cristovam Wanderley Picanço-Diniz Juliana Maria Carrazzone Borba Jailma Santos-Monteiro Rubem Carlos Araújo Guedes 《Nutritional neuroscience》2013,16(4):207-216
AbstractTissue distribution of nitric oxide-synthases was investigated in the rat hippocampus and visual cortex under nutritional changes induced by modification of the litter size. Young (30-45-days-old) rats, suckled in litters formed by 3, 6 or 12 pups (called small, medium and large litters, respectively), were studied by using nicotine-adenine-dinucleotide phosphate-diaphorase histochemistry (shortly, diaphorase), a simple and robust procedure to characterize tissue distribution of nitric oxide-synthases. We assessed morphometric features of the diaphorase-positive cells in visual cortex, and the neuropil histochemical activity in hippocampal CA1 and dentate gyrus using densitometry analysis. In the large-litter group, the labeled-cell density in white matter of area 17 was higher, as compared to the small-litter group. There was a clear trend, in the large-litter group, to lower values of soma area, dendritic field and branches per neuron, but the differences were not significant. Densitometry analysis of hippocampus revealed a significant increase in the relative neuropil histochemical activity of the dentate gyrus molecular layer in the larger litters, which may be associated to increased compensatory blood flow in the hippocampus. The pathophysiological mechanisms of the observed changes remain to be investigated. 相似文献
18.
An enzyme-linked immunosorbent assay has been developed for the quantitation of activated Hageman factor-C1 inactivator (HF-C1 INH) complexes. Addition of increasing quantities of either of the major forms of activated Hageman factor (HFa or HFf) to normal plasma or to Hageman factor-deficient plasma leads to a dose-dependent increase in activated HF-C1 INH complexes. As little as 0.5 micrograms/mL of activated HF added to plasma can be detected, corresponding to activation of approximately 2% of plasma HF. The sensitivity of the assay is increased at least tenfold when complexes are formed in HF- deficient plasma, indicating competition between unactivated HF and activated HF-C1 INH complexes for binding to the antibody. Specificity is demonstrated in that addition of activated HF to hereditary angioedema plasma yields less than 1% of the activated HF-C1 INH complex formation obtained with normal plasma. Kaolin activation of HF- deficient plasma yields no detectable complex formation. Kaolin activation of prekallikrein-deficient plasma demonstrates a time- dependent increase in formation of activated HF-C1 INH complex consistent with the ability of HF in this plasma to autoactivate as the time of incubation with the surface is increased. Kaolin treatment of high-molecular weight (HMW) kininogen-deficient plasma yields an even more profound abnormality in the rate of formation of activated HF-C1 INH complexes reflecting the complex role of HMW kininogen in the initiation of contact activation. Although addition of corn inhibitor to plasma prevents activated HF-C1 INH complex formation, it does not inhibit activated HF sufficiently fast to prevent prekallikrein activation. 相似文献
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Barbosa Wagner Faria De Meyer Laurens Guedes Raul Narciso C. Smagghe Guy 《Ecotoxicology (London, England)》2015,24(1):130-142
Ecotoxicology - Azadirachtin is a biorational insecticide commonly reported as selective to a range of beneficial insects. Nonetheless, only few studies have been carried out with pollinators,... 相似文献