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51.
Hypertensive disorders of pregnancy are a major cause of poor outcome, including placental abruption, organ failure, cerebrovascular accident and disseminated intravascular coagulation. These disorders are associated with increased fetal risk of intrauterine growth restriction, intrauterine death and prematurity. Electrocardiography (ECG) recently emerged as a useful tool to evaluate cardiovascular complications during pregnancy. Specifically, left atrial abnormalities detected by standard ECG are associated with a fourfold increased risk of developing hypertensive disorders during pregnancy. The mechanisms linking left atrial abnormality on ECG with hypertensive disorders are still elusive. Several mechanisms, possibly reflected by abnormal left atrial activation on ECG, has been suggested. These include increased reactivity to angiotensin II and up-regulation of angiotensin type 1 receptors, with activation of autoantibodies targeting these receptors.  相似文献   
52.
Celiac disease (CD) is a gluten-sensitive enteropathy with an immune basis. We established the immune reactivity of the alcohol-soluble fraction from two minor cereals (tef and millet) and two pseudocereals (amaranth and quinoa) which are believed to be nontoxic based on taxonomy. Grains were examined in intestinal T-cell lines (iTCLs), cultures of duodenal explants from HLA-DQ2(+) CD patients and HLA-DQ8 transgenic mice for signs of activation. Our data indicated that tef, millet, amaranth, and quinoa did not show any immune cross-reactivity toward wheat gliadin, and therefore confirming their safety in the diet of CD patients.  相似文献   
53.
This work represents a critical review of a selection of significant parking area projects chosen within the contemporary international context, aimed at discussing the role of parking architecture conceived as an opportunity to reinvent non-urban landscapes. Such an issue is part of the very topical broader theme of relationships between infrastructure and landscape, and of the various space and time scales on which landscape is perceived. Nowadays designers have to deal with several parking design opportunities related to the construction of intermodal stations, airports, shopping malls, industrial areas, as well as natural, cultural and leisure parks. Even if these places and design themes have now become usual, they still require an appropriate and original design research. Parking areas, besides their specific original function, can represent gardens and public spaces lying between the city and the countryside, capable of producing new hybrid landscapes blending art, nature and architecture.  相似文献   
54.
Objective: The aim of this study was to assess the mean of histamine concentration in food poisoning.

Design: Systematic review and meta-analysis of reports published between 1959 and 2013.

Study selection: Main criteria for inclusion of studies were: all report types that present outbreaks of “histamine poisoning' or “scombroid syndrome” from food, including histamine content and type of food. Health status of people involved must be nonpathological.

Results: Fifty-five (55) reports were included, these studies reported 103 incidents. All pooled analyses were based on random effect model; histamine mean concentration in poisoning samples was 1107.21 mg/kg with confidence interval for the meta-mean of 422.62–2900.78 mg/kg; heterogeneity index (I2) was 100% (P < 0.0001); prediction interval was 24.12–50822.78 mg/kg. Fish involved in histamine poisoning was mainly tuna or Istiophoridae species. No clues of association between concomitant conditions (female sex, alcohol consumption, previous medication, and consumption of histamine releasing food) and histamine poisoning, were highlighted.

Conclusions: This is the first systematic review and meta-analysis that analyzes all the available data on histamine poisoning outbreaks evaluating the histamine concentration in food involved. Histamine mean concentration in poisoning samples was fairly high. Our study suffers from some limitations, which are intrinsic of the studies included, for instance the lack of a complete anamnesis of each poisoning episode.

Protocol registration: Methods were specified in advance and have been published as a protocol in PROSPERO database (18/07/2012 -CRD42012002566).  相似文献   

55.
Crystallization still represents the bottleneck in the process of protein structure determination at high resolution, despite high‐throughput structural genomics programs requiring optimized crystallization strategies regarding crystal quality, time, success rate, reproducibility, and used protein amount. On the other hand, the development of suitable materials for controlled heterogeneous nucleation might facilitate biomacromolecular crystallization in a variety of experimental conditions which are not conventionally fruitful. Here, the possibility to fabricate hydrogel membranes displaying controlled chemical composition and nanostructure and to use them as heterogeneous supports for biomacromolecular crystallization is demonstrated. Diverse gel morphologies are obtained by controlling phase separation kinetics during gel layer formation on membrane support. These composite materials are found to increase the efficiency of the crystallization process so that crystals with enhanced diffraction properties are produced at lower protein concentration than conventional technique, thus affording the possibility to improve current approaches to protein crystallization and to be adapted to specific targets.  相似文献   
56.
High-throughput methods were employed to study the influence of reaction parameters on the synthesis of the metal-organic frameworks MOF-5 (Zn4O[(OOC)2 · C6H4]3) and HKUST-1 (Cu3[(OOC)3C6H3]2(H2O)3 · xH2O). Thus, compositional parameters (metal salt, reagent concentrations, and pH) as well as process parameters (temperature, time) were investigated in order to establish reaction trends and fields of formation. A multiclave reaction block was used to perform the investigation of 24 different solvothermal reactions at a time. Attention was focused on the phase purity and the crystal morphology of the resulting compounds. The characterization of the samples was performed by X-ray powder diffraction and high resolution scanning electron microscopy. The experimental results show that the formation, phase purity, and morphology of MOF-5 and HKUST-1 are extremely sensitive to the synthesis parameters explored in this study.  相似文献   
57.
The damage control sequence and underlying logic   总被引:1,自引:0,他引:1  
With the growing understanding of the pathophysiology of exsanguination has come the evolution of extraordinary surgical techniques designed to improve survival. As the success of damage control has grown, so has its acceptance in the traditional surgical community. Our challenge now is to scientifically define patient selection, refine intraoperative techniques, and acquire a greater clinical and basic science understanding of the physiology of exsanguination and reperfusion injury in resuscitation. In these efforts, overall survival should continue to increase and morbidity should continue to decrease.  相似文献   
58.
Cross-correlation and most other longitudinal analyses assume that the association between 2 variables is stationary. Thus, a sample of occasions of measurement is expected to be representative of the association between variables regardless of the time of onset or number of occasions in the sample. The authors propose a method to analyze the association between 2 variables when the assumption of stationarity may not be warranted. The method results in estimates of both the strength of peak association and the time lag when the peak association occurred for a range of starting values of elapsed time from the beginning of an experiment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
60.
Grafted titanium-containing mesoporous silica catalysts were used in the selective epoxidation of C-18 unsaturated fatty acid methyl esters (FAMEs). High yields in mono- and diepoxide derivatives were obtained under acid-free reaction conditions with TBHP as oxidant. Ti-MCM-41 showed the best performance in terms of activity over the three FAMEs. Easy separation of the desired products and recycling of the catalyst were demonstrated.  相似文献   
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