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排序方式: 共有868条查询结果,搜索用时 15 毫秒
1.
Enrico Bertino Carolina Bisson Claudio Martano Alessandra Coscia Claudio Fabris Giovanna Monti Tiziana Testa Amedeo Conti 《Pediatric allergy and immunology》2006,17(7):484-488
AIM: A positive correlation between maternal and cord-blood IgE levels is well documented for total IgEs, but not for specific IgEs. The difficulty in detecting specific cord-blood IgEs is due to their low concentrations, which hinder their dosage by low-sensitivity methods. The study aimed to correlate maternal and foetal specific IgEs against individual cow's milk proteins, detected by highly sensitive and specific techniques. METHODS: Cow's milk specific IgE detection was performed by chemiluminescence on 52 specimens of maternal and cord blood after cow's milk protein separation by 1D and 2D gel electrophoresis. Cow's milk protein (CMP) antigens were identified by mass spectrometry techniques. RESULTS: Specific IgEs for CMPs were found in 25/52 (48.1%) of maternal sera and in 19/52 (37%) of cord-blood sera. In order of decreasing frequency, the proteins found were BSA, IgG heavy chain, caseins and, in a single case, b-lactoglobulin. Positive cord-blood sera in all cases corresponded to a positive maternal result, and maternal and foetal immunoreactivity patterns were closely correlated. Moreover, in no case was there a positive cord-blood response with a negative maternal response. CONCLUSION: The study demonstrates a close relationship between maternal and cord-blood specific IgE patterns. The phenomenon observed could provide a model to elucidate the general production method of foetal IgEs, which might only be produced in the presence of both the corresponding maternal IgE and the related allergen. 相似文献
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The European Food Safety Authority is currently evaluating the risks related to the presence of emerging mycotoxins in food and feeds. The aim of this study was to investigate the role of soil fertility, resulting from different nitrogen fertilization rates, on the contamination of regulated mycotoxins and emerging fungal metabolites in maize grains. The trial was carried out in the 2012–2013 growing seasons as part of a long-term (20-year) experimental platform area in North-West Italy, where five different N rates, ranging from 0 to 400 kg N ha−1, were applied to maize each year. Maize samples were analyzed by means of a dilute-and-shoot multi-mycotoxin LC-MS/MS method, and more than 25 of the most abundant mycotoxins and fungal metabolites were detected. Contamination by fumonisins and other fungal metabolites produced by Fusarium spp. of the section Liseola was observed to have increased in soils that showed a poor fertility status. On the other hand, an overload of nitrogen fertilization was generally associated with higher deoxynivalenol and zearalenone contamination in maize kernels, as well as a higher risk of other fungal metabolites produced by Fusarium spp. sections Discolor and Roseum. A balanced application of N fertilizer, in accordance with maize uptake, generally appears to be the best solution to guarantee an overall lower contamination by regulated mycotoxins and emerging fungal metabolites. 相似文献
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Niloufar Zarinabad Amedeo Chiribiri Gilion L. T. F. Hautvast Masaki Ishida Andreas Schuster Zoran Cvetkovic Philip G. Batchelor Eike Nagel 《Magnetic resonance in medicine》2012,68(6):1994-2004
The purpose of this study is to enable high spatial resolution voxel‐wise quantitative analysis of myocardial perfusion in dynamic contrast‐enhanced cardiovascular MR, in particular by finding the most favorable quantification algorithm in this context. Four deconvolution algorithms—Fermi function modeling, deconvolution using B‐spline basis, deconvolution using exponential basis, and autoregressive moving average modeling —were tested to calculate voxel‐wise perfusion estimates. The algorithms were developed on synthetic data and validated against a true gold‐standard using a hardware perfusion phantom. The accuracy of each method was assessed for different levels of spatial averaging and perfusion rate. Finally, voxel‐wise analysis was used to generate high resolution perfusion maps on real data acquired from five patients with suspected coronary artery disease and two healthy volunteers. On both synthetic and perfusion phantom data, the B‐spline method had the highest error in estimation of myocardial blood flow. The autoregressive moving average modeling and exponential methods gave accurate estimates of myocardial blood flow. The Fermi model was the most robust method to noise. Both simulations and maps in the patients and hardware phantom showed that voxel‐wise quantification of myocardium perfusion is feasible and can be used to detect abnormal regions. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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Mandolfino T Canciglia A Lamberto S Carmignani A D'Alfonso M Bottari A 《Chirurgia italiana》2005,57(5):615-620
The purpose of this study was to compare magnetic resonance angiography with duplex ultrasound for defining anatomical features relevant to performing lower limb revascularisation. From June 2003 to June 2004, 30 consecutive patients with chronic lower limb ischaemia underwent magnetic resonance angiography and duplex ultrasound investigations before undergoing lower limb revascularisation procedures. The mean age was 72 years (range: 45-93). Indications for the procedure included resting pain (6 cases), ischaemic ulcer (8 cases), and gangrene (16 cases). We compared magnetic resonance angiography and duplex ultrasonography findings and the differences in the aorto-iliac, femoro-popliteal and infrapoliteal segments were noted. Magnetic resonance angiography and duplex ultrasound findings agreed in 13/15 cases (86%) in the aorto-iliac segment, in 14/17 (82%) in the femoro-popliteal segment, and in 8/11 (74%) in the infrapopliteal segment. In all, duplex ultrasound agreed with intraoperative findings in 97% of cases while magnetic resonance angiography agreed in 81%. These data show that magnetic resonance angiography is less accurate than duplex ultrasound in the infrapopliteal segment. Adeguate training is necessary before duplex ultrasound can be used as the only preoperative imaging procedure. 相似文献
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Vittorio Scaravilli Silvia Scansani Alice Grasso Amedeo Guzzardella Marco Vicenzi Irene Rota Mario Nosotti Alberto Zanella Francesco Blasi Antonio Pesenti Giacomo Grasselli 《Transplantation proceedings》2021,53(1):260-264
Knowledge of preoperative right heart function of adult patients with cystic fibrosis (CF) awaiting lung transplant (LUTX) is limited. The echocardiography of adult patients with CF enlisted for LUTX was retrospectively analyzed and compared with standards and invasive analyses (right heart catheterization, multigated radionuclide ventriculography). We included 49 patients (reported as mean ± standard deviation; 29 ± 9 years of age; forced expiratory volume in first second of expiration, 31% ± 11% predicted; lung allocation score, 36 ± 5; invasive mean pulmonary artery pressure, 17 ± 5 mm Hg; multigated radionuclide ventriculography right ventricle [RV] ejection fraction, 50% ± 9%). Patients had increased RV end-diastolic area, RV wall thickness, and increased pulmonary artery acceleration time with subnormal tricuspid annular plane systolic excursion, tissue Doppler positive peak systolic velocity, and fraction area change. Subnormal tricuspid annular plane systolic excursion (< 23 mm), tissue Doppler positive peak systolic velocity (< 14 cm/s), and fraction area change (< 49%) had high sensitivity and negative predictive value in predicting impaired RV.ejection fractionA good correlation between echocardiographic estimated and invasively measured systolic pulmonary artery pressure was observed (R2 = 0.554, P < .001). Adults with CF awaiting LUTX have morphologic alterations of the right heart, with subclinical impairment of RV systolic function. Echocardiography may be used as a bedside, repeatable, and reliable noninvasive test to screen further deterioration in RV function while on the waiting list for LUTX. More prospective follow-up echocardiographic studies are necessary to confirm such a hypothesis. 相似文献
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Mario Bonomini Lorenzo Di Liberato Goffredo Del Rosso Antonio Stingone Giancarlo Marinangeli Agostino Consoli Silvio Bertoli Amedeo De Vecchi Emanuele Bosi Roberto Russo Roberto Corciulo Loreto Gesualdo Francesco Giorgino Paolo Cerasoli Augusto Di Castelnuovo Maria Pia Monaco Ty Shockley Claudia Rossi Arduino Arduini 《American journal of kidney diseases》2013
8.
Amedeo Lonardo Alessandro Mantovani 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(8):2354-2357
Liver health is a key determinant of cardiovascular risk (CVR). Hepatic fibrosis is the shared common result of chronic hepatitis, irrespective of aetiology. Fibrosis profoundly distorts liver tissue architecture and perturbs hepatic physiology, dictates the course of chronic liver disease and is increasingly recognized as a CVR factor. The relative weights of pre-diabetes and hepatic fibrosis as risk factors for major adverse cardiac events (MACE) in patients with HCV remain an open issue. Sasso and Colleagues answered this research question by treating approximately half of 770 HCV positive pre-diabetic patients with direct antiviral agents (DAAs), while the rest served as historical controls. Data have shown that achieving HCV clearance with DAAs was associated with a 60% reduced risk of MACE, thereby implying that this antiviral strategy is recommended in HCV positive pre-diabetic patients, regardless of the severity of liver disease and concurrent CVR factors. This study paves the way for additional studies addressing the molecular patho-mechanisms and changes in the clinical spectrum involved in cardio-metabolic protection following HCV eradication in patients with pre-diabetes. 相似文献
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