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排序方式: 共有3488条查询结果,搜索用时 15 毫秒
71.
Carlos Müller-Arteaga Alicia Martín Martinez Bárbara Padilla-Fernández Pedro Blasco Hernández Montserrat Espuña Pons Francisco Cruz Carlos Errando-Smet Roberto Martínez-García Eduardo Vicente Palacio David Castro Díaz Luis López-Fando Blanca Madurga Patuel Cristina Ros Cerro Salvador Arlandis Guzmán 《Neurourology and urodynamics》2020,39(1):464-469
72.
Enriqueta Antic Ruben Vera Francisco Vzquez Cludia Fonts Changyong Lu Josep Ros 《Materials》2021,14(4)
Nanoparticle-doped polymer inclusion membranes (NP-PIMs) have been prepared and characterized as new materials for the removal of arsenate and phosphate from waters. PIMs are made of a polymer, cellulose triacetate (CTA), and an extractant, which interacts with the compound of interest. We have used the ionic liquid (IL) trioctylmethylammonium chloride (Aliquat 336) as the extractant and have investigated how the addition of nanoparticles can modify membrane properties. To this end, inorganic nanoparticles, such as ferrite (Fe3O4), SiO2 and TiO2, and multiwalled carbon nanotubes (MWCNTs), were blended with the polymer/extractant mixture. Scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), and contact angle measurements have been used to characterize the material. Moreover, PIM stability was checked by measuring the mass loss during the experiments. Since Aliquat 336 acts as an anion exchanger, the NP-PIMs have been explored in two different applications: (i) as sorbent materials for the extraction of arsenate and phosphate anions; (ii) as an organic phase for the separation of arsenate and phosphate in a three-phase system. The presence of oleate-coated ferrite NP in the PIM formulation represents an improvement in the efficiency of NP-PIMs used as sorbents; nevertheless, a decrease in the transport efficiency for arsenate but not for phosphate was obtained. The ease with which the NP-PIMs are prepared suggests good potential for future applications in the treatment of polluted water. Future work will address three main aspects: firstly, the implementation of the Fe3O4-PIMs for the removal of As(V) in real water containing complex matrices; secondly, the study of phosphate recovery with other cell designs that allow large volumes of contaminated water to be treated; and thirdly, the investigation of the role of MWCNTs in PIM stability. 相似文献
73.
DnaK dependence of mutant ethanol oxidoreductases evolved for aerobic function and protective role of the chaperone against protein oxidative damage in Escherichia coli 下载免费PDF全文
Echave P Esparza-Cerón MA Cabiscol E Tamarit J Ros J Membrillo-Hernández J Lin EC 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(7):4626-4631
The adhE gene of Escherichia coli encodes a multifunctional ethanol oxidoreductase (AdhE) that catalyzes successive reductions of acetyl-CoA to acetaldehyde and then to ethanol reversibly at the expense of NADH. Mutant JE52, serially selected for acquired and improved ability to grow aerobically on ethanol, synthesized an AdhE(A267T/E568K) with two amino acid substitutions that sequentially conferred improved catalytic properties and stability. Here we show that the aerobic growth ability on ethanol depends also on protection of the mutant AdhE against metal-catalyzed oxidation by the chaperone DnaK (a member of the Hsp70 family). No DnaK protection of the enzyme is evident during anaerobic growth on glucose. Synthesis of DnaK also protected E. coli from H2O2 killing under conditions when functional AdhE is not required. Our results therefore suggest that, in addition to the known role of protecting cells against heat stress, DnaK also protects numerous kinds of proteins from oxidative damage. 相似文献
74.
Cejudo-Martín P Ros J Navasa M Fernández J Fernández-Varo G Ruiz-del-Arbol L Rivera F Arroyo V Rodés J Jiménez W 《Hepatology (Baltimore, Md.)》2001,34(3):487-493
Spontaneous bacterial peritonitis (SBP) is a common complication of cirrhotic patients with ascites that usually results in renal failure and death despite the efficacy of the current antibiotic therapy. The pathogenesis of these phenomena is poorly known but it has been related to the production of vasoactive cell mediators locally acting on the splanchnic vasculature. Because previous studies showed that peritoneal macrophages of cirrhotic patients may produce high quantities of vascular endothelial growth factor (VEGF), a powerful vessel permeabilizing agent, when stimulated by cytokines and bacterial lipopolysaccharide, the present study was aimed to seek whether peritoneal macrophages of SBP patients are induced to produce increased amounts of VEGF. Our results indicate that the production rate and the messenger RNA (mRNA) and protein expression of this substance are increased in macrophages of patients with SBP in comparison with those of noninfected cirrhotic patients. This characteristic feature is absent in circulating monocytes of these patients. Moreover, enhanced endothelial cell proliferation induced by conditioned medium of macrophages isolated from the ascites of patients with SBP is abolished by anti-VEGF antibody, and peritoneal tissue of cirrhotic patients expresses both VEGF receptors, Flt-1 and KDR. These results, therefore, are consistent with the concept that locally released macrophage-derived VEGF may result in increased vascular permeability and plasma leakage in the peritoneal vessels of cirrhotic patients with SBP. 相似文献
75.
Vanina A. Netti Mariana C. Vatrella Melina F. Chamorro María I. Rosón Elsa Zotta Andrea L. Fellet Ana M. Balaszczuk 《European journal of nutrition》2014,53(1):287-295
Purpose
Aquaporin-1 (AQP1) is the predominant water channel in the heart, linked to cardiovascular homeostasis. Our aim was to study cardiovascular AQP1 distribution and protein levels during osmotic stress and subsequent hydration during postnatal growth.Methods
Rats aged 25 and 50 days were divided in: 3d-WR: water restriction 3 days; 3d-WAL: water ad libitum 3 days; 6d-WR+ORS: water restriction 3 days + oral rehydration solution (ORS) 3 days; and 6d-WAL: water ad libitum 6 days. AQP1 was evaluated by immunohistochemistry and western blot in left ventricle, right atrium and thoracic aorta.Results
Water restriction induced a hypohydration state in both age groups (40 and 25 % loss of body weight in 25- and 50-day-old rats, respectively), reversible with ORS therapy. Cardiac AQP1 was localized in the endocardium and endothelium in both age groups, being evident in cardiomyocytes membrane only in 50-day-old 3d-WR group, which presented increased protein levels of AQP1; no changes were observed in the ventricle of pups. In vascular tissue, AQP1 was present in the smooth muscle of pups; in the oldest group, it was found in the endothelium, increasing after rehydration in smooth muscle. No differences were observed between control groups 3d-WAL and 6d-WAL of both ages.Conclusion
Our findings suggest that cardiovascular AQP1 can be differentially regulated in response to hydration status in vivo, being this response dependent on postnatal growth. The lack of adaptive mechanisms of mature animals in young pups may indicate an important role of this water channel in maintaining fluid balance during hypovolemic state. 相似文献76.
77.
78.
Azuaga A. B. Frade-Sosa B. Laiz A. Estrada P. Prior-Español A. Horcada L. Polino L. Moreno M. Moragues C. Urruticoechea-Arana A. Sellas A. Tandaipan J. L. Torrente-Segarra V. Garcia-Miguel J. Ros I. Ordoñez S. Moya P. Reina D. Mateo-Soria L. Fito C. Beltrán E. Pujol M. Cuervo A. M. Cañete J. D. Ramírez Julio 《Clinical rheumatology》2020,39(10):2963-2971
Clinical Rheumatology - To assess the effectiveness and survival of ustekinumab (UST) among patients with psoriatic arthritis (PsA) treated under routine clinical care. Multicenter study.... 相似文献
79.
Marli Teresinha Cassamassimo Duarte Cristina Maria Garcia de Lima Parada Lenice do Rosário de Souza 《Revista latino-americana de enfermagem》2014,22(1):68-75
Objective
outline the profile of women living with the human immunodeficiency virus/aids in interior cities in São Paulo State, in the attempt to identify characteristics related to individual, social and programmatic vulnerability and to analyze the conditions in which they discovered their serological status.Method
between October 2008 and December 2010, a cross-sectional study was undertaken with 184 women attended at a specialized service. The data were collected through an interview and gynecological test, including the collection of samples for the etiological diagnosis of sexually transmissible conditions.Results
the women were predominantly white, between 30 and 49 years of age, lived with a partner, had a low education level, multiple sexual partners across the lifetime and unsafe sexual practices. The prevalence of sexually transmitted diseases corresponded to 87.0%.Conclusion
the study suggests the need to offer gynecological care in specialized services and the accomplishment of multiprofessional actions to reinforce the female autonomy in protective decision making. 相似文献80.
Julie T-W. Wang Chiara Fabbro Enrica Venturelli Cécilia Ménard-Moyon Olivier Chaloin Tatiana Da Ros Laura Methven Antonio Nunes Jane K. Sosabowski Stephen J. Mather Martyn K. Robinson Julien Amadou Maurizio Prato Alberto Bianco Kostas Kostarelos Khuloud T. Al-Jamal 《Biomaterials》2014
Carbon nanotubes (CNTs) exhibit unique properties which have led to their applications in the biomedical field as novel delivery systems for diagnosis and therapy purposes. We have previously reported that the degree of functionalization of CNTs is a key factor determining their biological behaviour. The present study broadens the spectrum by investigating the impact of the diameter of CNTs using two series of multi-walled CNTs (MWNTs) with distinct differences in their diameters. Both MWNTs were doubly functionalized by 1,3-dipolar cycloaddition and amidation reactions, allowing the appended functional groups to be further conjugated with radionuclide chelating moieties and antibodies or antibody fragments. All constructs possessed comparable degree of functionalization and were characterized by thermogravimetric analysis, transmission electron microscopy, gel electrophoresis and surface plasmon resonance. The MWNT conjugates were radio-labelled with indium-111, which thereby enabled in vivo single photon emission computed tomography/computed tomography (SPECT/CT) imaging and organ biodistribution study using γ-scintigraphy. The narrow MWNTs (average diameter: 9.2 nm) demonstrated enhanced tissue affinity including non-reticular endothelial tissues compared to the wider MWNTs (average diameter: 39.5 nm). The results indicate that the higher aspect ratio of narrow MWNTs may be beneficial for their future biological applications due to higher tissue accumulation. 相似文献