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排序方式: 共有4392条查询结果,搜索用时 265 毫秒
991.
Chiara Donfrancesco Cinzia Lo Noce Ornella Russo Daniela Minutoli Anna Di Lonardo Elisabetta Profumo Brigitta Buttari Roberto Iacone Francesca Vespasiano Serena Vannucchi Graziano Onder Ferruccio Galletti Daniela Galeone Paolo Bellisario Michele M. Gulizia Simona Giampaoli Luigi Palmieri Pasquale Strazzullo 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(3):802-813
Background and aimsThe WHO Global Action Plan for the Prevention of non-communicable diseases (NCDs) recommends a 30% relative reduction in mean population salt/sodium intake. The study assessed the trend in the habitual salt intake of the Italian adult population from 2008 to 2012 to 2018–2019 based on 24-h urinary sodium excretion, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIU’ SALUTE national surveys.Methods and resultsData were from cross-sectional surveys of randomly selected age and sex–stratified samples of resident persons aged 35–74 years in 10 (out of 20) Italian Regions distributed in North, Centre and South of the Country. Urinary sodium and creatinine measurements were carried out in a central laboratory. The analyses included 942 men and 916 women examined in 2008–2012, and 967 men and 1010 women examined in 2018–2019. The age-standardized mean daily population salt (sodium chloride) intake was 10.8 g (95% CI 10.5–11.1) in men and 8.3 g (8.1–8.5) in women in 2008–2012 and respectively 9.5 g (9.3–9.8) and 7.2 g (7.0–7.4) in 2018–2019. A statistically significant (p<0.0001) salt intake reduction was thus observed over 10 years for both genders, and all age, body mass index (BMI) and educational classes.ConclusionsThe average daily salt intake of the Italian general adult population remains higher than the WHO recommended level, but a significant reduction of 12% in men and 13% in women has occurred in the past ten years. These results encourage the initiatives undertaken by the Italian Ministry of Health aimed at the reduction of salt intake at the population level. 相似文献
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Anna Norhammar MD Johan Bodegard MD Jan W. Eriksson MD Hermann Haller MD Gerard C. M. Linssen MD Amitava Banerjee MD Avraham Karasik MD Pavlos Mamouris PhD Navdeep Tangri MD Tiago Taveira-Gomes MD Aldo P. Maggioni MD Manuel Botana MD Marcus Thuresson PhD Suguru Okami PhD Toshitaka Yajima MD Takashi Kadowaki MD Kåre I. Birkeland MD CaReMe Cardiorenal Investigators 《Diabetes, obesity & metabolism》2022,24(7):1277-1287
994.
Yunier Garcia-Basabe Denis Ceolin Aldo J. G. Zarbin Lucimara S. Roman Maria Luiza M. Rocco 《RSC advances》2018,8(46):26416
The interfacial electronic structure and charge transfer dynamics of poly-3-hexylthiophene (P3HT) and multi-walled carbon nanotube (Fe-MWCNT) nanocomposites were investigated by near-edge X-ray absorption fine structure (NEXAFS) and resonant Auger (RAS) spectroscopies around the sulfur K-edge. Nanocomposites with 5 wt% (P3HT/Fe-MWCNT-5%) and 10 wt% (P3HT/Fe-MWCNT-10%) of Fe-MWCNT species were prepared and compared with pristine P3HT film. The quantitative NEXAFS analysis shows a strong π–π interchain interaction of the pristine P3HT polymer film, which is reduced by the presence of the Fe-MWCNT. S–KL2,3L2,3 RAS spectra were measured at photon energies corresponding to the main electronic transitions appearing in the S–K edge NEXAFS spectrum. Ultrafast charge transfer times were estimated from the RAS spectra using the core-hole clock approach with the S 1s core-hole lifetime as an internal clock. The π–π interchain charge transfer time increases from 4.7 fs on pristine P3HT polymer to 6.5 fs on the P3HT/Fe-MWCNT-5% nanocomposite. The electronic coupling between P3HT and Fe-MWCNT species occurs mainly through the P3HT π* molecular orbital. The increase of Fe-MWCNT concentration from 5 to 10 wt% reduces the charge transfer rate at the resonance maximum due probably to Fe-MWCNT aggregation, reducing the P3HT and Fe-MWCNT electronic coupling.The electronic coupling between P3HT polymer and multi-walled carbon nanotubes was elucidated using NEXAFS and core hole clock approaches. 相似文献
995.
Moises Martinez-Castillo Abigail Hernandez-Barragan Ivonne Flores-Vasconcelos Marina Galicia-Moreno Dorothy Rosique-Oramas Jose Luis Perez-Hernandez Fatima Higuera-De la Tijera Eduardo E Montalvo-Jave Aldo Torre-Delgadillo Paula Cordero-Perez Linda Mu oz-Espinosa David Kershenobich Gabriela Gutierrez-Reyes 《World journal of hepatology》2021,13(2):218-232
BACKGROUNDMatrix metalloproteinases (MMPs) participate in the degradation of extracellular matrix compounds, maintaining the homeostasis between fibrogenesis and fibrolytic processes in the liver. However, there are few studies on the regulation of liver MMPs in fibrosis progression in humans. AIMTo assess the production activity and regulation of matrix metalloproteinases in liver fibrosis stages in chronic hepatitis C (CHC).METHODSA prospective, cross-sectional, multicenter study was conducted. CHC patients were categorized in fibrosis grades through FibroTest®and/or FibroScan®. Serum MMP-2, -7, and -9 were determined by western blot and multiplex suspension array assays. Differences were validated by the Kruskal-Wallis and Mann-Whitney U tests. The Spearman correlation coefficient and area under the receiver operating characteristic curve were calculated. Collagenolytic and gelatinase activity was determined through the Azocoll substrate and zymogram test, whereas tissue inhibitor of metalloproteinase-1 production was determined by dot blot assays.RESULTSSerum concentrations of the MMPs evaluated were higher in CHC patients than in healthy subjects. MMP-7 distinguished early and advanced stages, with a correlation of 0.32 (P < 0.001), and the area under the receiver operating characteristic displayed moderate sensitivity and specificity for MMP-7 in F4 (area under the receiver operating characteristic, 0.705; 95% confidence interval: 0.605-0.805; P < 0.001). Collagenolytic activity was detected at F0 and F1, whereas gelatinase activity was not detected at any fibrosis stage. Tissue inhibitor of metalloproteinase-1 determination showed upregulation in F0 and F1 but downregulation in F2 (P < 0.001). CONCLUSIONHigh concentrations of inactive MMPs were present in the serum of CHC patients, reflecting the impossibility to restrain liver fibrosis progression. MMPs could be good diagnostic candidates and therapeutic targets for improving novel strategies to reverse liver fibrosis in CHC. 相似文献
996.
Roberta Cond Gianluca Mampieri Guido Pasquantonio Aldo Giancotti Paola Pirelli Maria Elena Cataldi Serena La Rocca Andrea Leggeri Andrea Notargiacomo Luca Maiolo Patrizia De Filippis Loredana Cerroni 《Materials》2021,14(10)
Bacterial adhesion to the surface of orthodontic materials is an important step in the formation and proliferation of plaque bacteria, which is responsible for enamel demineralization and periodontium pathologies. With the intent of investigating if adhesive resins used for bracket bonding are prone to bacteria colonization, the surface roughness of these materials has been analyzed, combining information with a novel methodology to observe the internal structures of orthodontic composites. Scanning electron microscopy, combined with focus ion bean micromachining and stylus profilometry analyses, were performed to evaluate the compositional factors that can influence specific pivotal properties facilitating the adhesion of bacteria to the surface, such as surface roughness and robustness of three orthodontic adhesive composite resins. To confirm these findings, contact angle measurements and bacteria incubation on resin slide have been performed, evaluating similarities and differences in the final achievement. In particular, the morphological features that determine an increase in the resins surface wettability and influence the bacterial adhesion are the subject of speculation. Finally, the focused ion beam technique has been proposed as a valuable tool to combine information coming from surface roughness with specific the internal structures of the polymers. 相似文献
997.
Essential tremor (ET) is the most common pathological tremor disorder in the world, and post-mortem evidence has shown that the cerebellum is the most consistent area of pathology in ET. In the last few years, advanced neuroimaging has tried to confirm this evidence. The aim of the present review is to discuss to what extent the evidence provided by this field of study may be generalised. We performed a systematic literature search combining the terms ET with the following keywords: MRI, VBM, MRS, DTI, fMRI, PET and SPECT. We summarised and discussed each study and placed the results in the context of existing knowledge regarding the cerebellar involvement in ET. A total of 51 neuroimaging studies met our search criteria, roughly divided into 19 structural and 32 functional studies. Despite clinical and methodological differences, both functional and structural imaging studies showed similar findings but without defining a clear topography of neurodegeneration. Indeed, the vast majority of studies found functional and structural abnormalities in several parts of the anterior and posterior cerebellar lobules, but it remains to be established to what degree these neural changes contribute to clinical symptoms of ET. Currently, advanced neuroimaging has confirmed the involvement of the cerebellum in pathophysiological processes of ET, although a high variability in results persists. For this reason, the translation of this knowledge into daily clinical practice is again partially limited, although new advanced multivariate neuroimaging approaches (machine-learning) are proving interesting changes of perspective. 相似文献
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