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921.
E Ros X Armengol L Grande V Toledo-Pimentel G Lacima G Sanz 《Canadian Metallurgical Quarterly》1997,42(7):1344-1353
Severe nonexertional (resting) chest pain may be due to myocardial ischemia, esophageal dysfunction, psychiatric disorder, or any combination thereof and frequently poses a difficult diagnostic challenge. Our aim was to investigate causes of chest pain in patients with coronary artery disease. Forty-five patients with angiographically proven obstructive coronary lesions and recurrent chest pain at rest were studied; 18 had refractory pain despite cardiac therapy (problem group), and 27 had documented myocardial ischemia (control group). Esophageal manometry, edrophonium provocation, 24-hr pH studies, and psychiatric interview were performed in all patients. The clinical evolution and the outcome of specific treatment during follow-up was used to establish the etiology of chest pain. Esophageal dysfunction was identified in all problem patients and in 52% of controls, and the esophagus was incriminated as the source of pain in 8 (44%) and 5 (18.5%), respectively. After a mean follow-up of 49 months (range 24-76 months), the cause of chest pain in the problem group was identified as panic disorder in 9 patients (50%), gastroesophageal reflux in 6 (33%), esophageal dysmotility in 2 (11%), and gallstone disease in 1 (6%). Of the control patients, 18 (67%) had ischemic pain alone, while 9 had concurrent causes: panic disorder in 5 (19%) and esophageal dysfunction in 4 (15%). Esophageal dysfunction and psychiatric disturbances are common in patients with coronary artery disease presenting with resting chest pain, and may contribute to patients' symptoms. 相似文献
922.
Jordi Guiteras Elena Crespo Pere Fontova Nuria Bolaos Montse Gom Esther Castao Oriol Bestard Josep M. Griny Joan Torras 《International journal of molecular sciences》2022,23(15)
Systemic lupus erythematosus is a complex autoimmune disorder mostly mediated by B-cells in which costimulatory signals are involved. This immune dysregulation can cause tissue damage and inflammation of the kidney, resulting in lupus nephritis and chronic renal failure. Given the previous experience reported with CTLA4-Ig as well as recent understanding of the PD-1 pathway in this setting, our group was encouraged to evaluate, in the NZBWF1 model, a human fusion recombinant protein (Hybri) with two domains: CTLA4, blocking the CD28—CD80 costimulatory pathway, and PD-L2, exacerbating the PD-1–PD-L2 coinhibitory pathway. After achieving good results in this model, we decided to validate the therapeutic effect of Hybri in the more severe MRL/lpr model of lupus nephritis. The intraperitoneal administration of Hybri prevented the progression of proteinuria and anti-dsDNA antibodies to levels like those of cyclophosphamide and reduced the histological score, infiltration of B-cells, T-cells, and macrophages and immune deposition in both lupus-prone models. Additionally, Hybri treatment produced changes in both inflammatory-related circulating cytokines and kidney gene expression. To summarize, both in vivo studies revealed that the Hybri effect on costimulatory-coinhibitory pathways may effectively mitigate lupus nephritis, with potential for use as a maintenance therapy. 相似文献
923.
Atmospheric transport and deposition of polycyclic aromatic hydrocarbons (PAHs) over tropical oceans has not yet been studied even though tropical oceans account for 35% of the global oceans. Here we show the results from measurements of gas- and aerosol-phase PAHs and dry deposition samples in the NE tropical Atlantic Ocean atmosphere, a region between 26 degrees and 21 degrees N, off shore of the Saharan desert. The results show that PAHs concentrations are high at the coastal ocean (15-20 ng m(-3) for sum of 27 gas-phase individual PAHs) and decrease by a factor of 2-3 at open ocean (26 degrees W). The spatial variability observed is consistent with dilution, reaction, and deposition during transport. Atmospheric dry deposition velocities ranged between 0.1 and 0.3 cm s(-1) with higher deposition velocities for the more volatile PAHs. Outbreaks of Saharan Dust significantly increase the deposition rates of PAHs. The occurrence and deposition of PAHs in tropical regions is complex and results from the interplay of a number of processes, such as wind speed, aerosol loads, important sources from West Africa, processes controlling the diurnal variability, and sequestration driven by high primary productivity regions. The measured average atmospheric residence times of gas- and aerosol-phase PAHs are 3.7 and 3.5 days, respectively. 相似文献
924.
Rodríguez LP Vilariño N Molgó J Aráoz R Antelo A Vieytes MR Botana LM 《Analytical chemistry》2011,83(15):5857-5863
The spirolides and gymnodimines are marine phycotoxins included in the group of cyclic imines. The toxicity of these compounds to humans is still unknown, although their toxicity by intraperitoneal injection in rodents is very high. A receptor-based method was developed using the competition of the 13-desmethyl spirolide C with biotin-labeled α-bungarotoxin for binding to nicotinic acetylcholine receptors and the immobilization of the α-bungarotoxin-receptor complex on streptavidin-coated surfaces. The quantification of the immobilized receptor can be achieved using a specific antibody. Finally, after the addition of a secondary antibody labeled with horseradish peroxidase, three alternative substrates of this enzyme generate a chemiluminescent, fluorescent, or colorimetric signal. The assay performs well in shellfish extracts and the detection range is 5-150 nM of 13-desmethyl spirolide C in shellfish extracts, which is at least 5 times more sensitive than the existing fluorescence polarization assay. This assay can also detect gymnodimine, although with 10 times lower sensitivity than the spirolide. The detection of cyclic imines with microplate assays would be useful for screening purposes in order to reduce the number of samples to be processed by bioassays or analytical methods. 相似文献
925.
We describe the optical properties of gold island films embedded between SiO2 and/or TiO2 layers. Plasmonic properties of gold films have been characterized using spectrometry and variable angle spectroscopic ellipsometry for various combinations of the embedding media. The obtained refractive indices of embedded gold island films have been used in the design of several types of multilayer reflectors. 相似文献
926.
Nizzetto L Gioia R Galea CL Dachs J Jones KC 《Environmental science & technology》2011,45(18):7834-7840
Partitioning behavior of hydrophobic and semivolatile chemicals (such as many POPs and PAHs) in water is key in controlling their environmental distribution and fate. A new equilibrium method is presented here which allows determination of the equilibrium partition coefficient of hexachlorobenzene with suspended particle (K(SPM)≈ 337 L gOC(-1)) in a complex bulk water sample by correcting for a number of sampling artifacts and for the presence of dissolved matter. The method provides simultaneous experimental determination of the fraction of chemical truly dissolved in water (representing in this case about 54% of the bulk water concentration) and that associated to DM (21%). The Henry's law constant was also experimentally determined during the K(SPM) measurements, providing information on the occurrence of partitioning equilibrium in the system for each single observation. Results showed that the high level of quality control and accuracy provided confidence intervals for the K(SPM) estimates within 1 order of magnitude. 相似文献
927.
928.
929.
Multimedia Tools and Applications - Digital videos have an important (and increasing) presence in learning processes, especially within online universities and schools. However, creating videos is... 相似文献
930.
Jordi López-Tamayo Raul Ramos Jordi Suriñach i Caralt 《The Annals of Regional Science》2018,60(3):613-636
The objective of this article is to analyse the recent evolution of European neighbouring countries in different dimensions related to economic performance (measured in a broader sense), social progress and institutional reforms. With this aim, we design and build a composite indicator to measure these different dimensions. Next, the index is used to characterise the relative evolution of neighbouring countries compared to a wide sample of developed and developing economies. We also test whether a convergence process has taken place in these different dimensions controlling for the potential effect of the European neighbourhood policy. The obtained results show different trends according to the considered dimensions and heterogeneous effects at the country level. From a policy perspective, these results reinforce the validity of the bilateral action plans that have characterised ENP recognising the different starting point and particular characteristics of each neighbouring country. 相似文献