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51.
The levels of fumonisins (FUMO)—mycotoxins produced by Fusarium verticillioides—in maize for food and feed are subject to European Union regulations. Compliance with the regulations requires the targeting of, among others, the agroclimatic factors influencing fungal contamination and FUMO production. Arvalis-Institut du végétal has created a national, multiyear database for maize, based on field survey data collected since 2003. This database contains information about agricultural practices, climatic conditions and FUMO concentrations at harvest for 738 maize fields distributed throughout French maize-growing regions. A linear mixed model approach highlights the presence of borers and the use of a late variety, high temperatures in July and October, and a water deficit during the maize cycle as creating conditions favoring maize contamination with Fusarium verticillioides. It is thus possible to target a combination of risk factors, consisting of this climatic sequence associated with agricultural practices of interest. The effects of the various possible agroclimatic combinations can be compared, grouped and classified as promoting very low to high FUMO concentrations, possibly exceeding the regulatory threshold. These findings should facilitate the creation of a national, informative and easy-to-use prevention tool for producers and agricultural cooperatives to manage the sanitary quality of their harvest.  相似文献   
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Melasma represents a pigmentary disorder that is difficult to treat. This study aims to broadly review the use of ablative lasers (Er:YAG and CO2) in the treatment of melasma, presenting the level of evidence of studies published to date. A total of 75 patients were enrolled in four case series studies (n=39), one controlled clinical trial (n=6) and one randomized controlled clinical trial (n=30). Studies on the Er:YAG laser showed better results with the use of short square-shaped pulses, which determined low rates of post-inflammatory hyperpigmentation and long-lasting maintenance of results. Likewise, studies on the CO2 laser proved the benefits of short pulse duration along with low-density energy. Post-treatment maintenance with the use of antipigmenting creams was necessary and effective to sustain long-term results. Ablative lasers may represent another useful and effective tool against melasma. Postinflammatory hyperpigmentation and difficulty in sustaining long-term results still represent the main limitations to a broader use of ablative lasers. Based on actual evidence, the use of this technology should be restricted to patients with recalcitrant disease. Further studies will help establish optimal laser parameters and treatment regimens.  相似文献   
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ObjectivesTo determine the prevalence of pneumococcal serotypes and antimicrobial susceptibility in patients with meningitis, and to evaluate the implications for vaccine coverage.MethodsPneumococcal strains obtained from normally sterile fluids from patients admitted with meningitis were isolated at the Hospital de Clínicas of the Universidade Federal de Uberlândia, Minas Gerais State, and sent to the Instituto Adolfo Lutz, city of São Paulo, São Paulo State, for further identification, serotyping, and antimicrobial susceptibility determination.ResultsFrom April 1999 to April 2009, 338 pneumococcal strains were isolated, and 72 obtained from patients with meningitis, were analyzed. Patients’ ages varied from one month to 82.2 years (mean of 18.4 ± 22.9 years; median of 5.2 years) and 46 (63.9%) patients were male. Strains were isolated from cerebrospinal fluid [66 occasions (91.7%)] and blood [6 occasions (8.3%)]. The most commonly identified serotypes were 14, 19F, 3, 7F, 6A, 6B, 10A, 18C, 23F, 5, and 34. Of the 20 [27.8%] oxacillin-resistant strains, 17 [23.6%] were resistant to penicillin and nine [12.5%] to ceftriaxone, both resistance patterns being more common in children aged two years or less and during the 2005–2009 period.ConclusionsResistance to penicillin and ceftriaxone was detected in 23.6% and 12.5% of the strains, respectively, and predominated in children aged two years or less and during the 2005–2009 period. There were 24 different serotypes of pneumococcus and 79.8% of the serotypes were represented in the 7-valent conjugated vaccine [PVC7].  相似文献   
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Apical hypertrophic cardiomyopathy (HCM) is an uncommon variant of HCM characterized by apical hypertrophy without the septal predominance seen in the majority of HCM cases. In 2% of patients, a concomitant left ventricular apical aneurysm is observed, which increases the risk of sudden death and adverse HCM‐related events. Multimodality imaging is helpful for appropriate identification of this particular morphologic pattern. Herein, we present a case of apical HCM with a left ventricular apical aneurysm, exemplifying the utility of a multimodality approach from resting electrocardiogram, transthoracic echocardiogram, left ventriculography, and cardiac magnetic resonance imaging, for proper risk stratification and treatment planning.  相似文献   
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Pre-implantation genetic diagnosis for aneuploidy testing (PGD-A) is a tool to identify euploid embryos during IVF. The suggested populations of patients that can benefit from it are infertile women of advanced maternal age, with a history of recurrent miscarriages and/or IVF failures. However, a general consensus has not yet been reached.After the clinical failure of its first version based on cleavage stage biopsy and 9 chromosome-FISH analysis, PGD-A is currently performed by 24 chromosome screening techniques on trophectoderm (TE) biopsies. This approach has been clearly demonstrated to involve a higher clinical efficiency with respect to the standard care, in terms of sustained pregnancy rate per transfer and lower miscarriage rate. However, data about PGD-A efficacy calculated on a per intention-to-treat basis, as well as an analysis of its cost-effectiveness, are still missing.TE biopsy is a safe and extensively validated approach with low biological and technical margin of error. Firstly, the prevalence of mosaic diploid/aneuploid blastocysts is estimated to be between 0 and 16 %, thus largely tolerable. Secondly, all the comprehensive chromosome screening (CCS) technologies adapted to, or designed to conduct PGD-A are highly concordant, and qPCR in particular has been proven to show the lowest false positive error rate (0.5 %) and a clinically recognizable error rate per blastocyst of just 0.21 %.In conclusion, there is a sufficient body of evidence to support the clinical application of CCS-based PGD-A on TE biopsies. The main limiting factor is the need for a high-standard laboratory to conduct blastocyst culture, biopsy and vitrification without impacting embryo viability.  相似文献   
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Effective height,which represents the height difference between the central free margins and the aortic insertion lines can be easily determined by 2-D echocardiography and allows for identification of prolapse in the native cusps and assessment of prolapse correction after valve repair.Nonetheless,it allows to see only two of three aortic valve(AV)coaptation planes and this may lead to misunderstanding of the underlying pathophysiological mechanism for aortic regurgitation and hence in unsuccessful repair.In contrast,3D transoesophageal echocardiography and multiple plane reconstruction lets visualize all the three coaptation planes between the AV cusps and it represents an invaluable tool in the assessment of aortic valve geometry.It is highly recommendable before AV repair to accurately study the complex three dimensional cusps anatomy and their geometric interrelation with aortic root.  相似文献   
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