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1.
Sci Rep ; 9(1): 8597, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31197241

RESUMO

We propose a high temporal resolution numerical algorithm for shock wave velocity diagnosis. By analysing variations in the optical path and phasor of a light field, we determine a high temporal resolution shock wave velocity equation for a velocity interferometer system for any reflector (VISAR). The equation can be transformed into matrix form for numerical solution. To solve noise problems, a 'filtering velocity spectrum' method is proposed. Analysis of a VISAR data example shows that the resolution precision of shock wave velocity obtained from the numerical algorithm is the same as the temporal resolution of a streak camera. Moreover, it can observe the shock wave in greater detail. This algorithm can be used to observe detailed images and determine the mechanism and evolution of extreme shock waves, as well as provide data for research into hydrodynamic behaviour in inertial confinement fusion.

2.
Int J Biol Macromol ; 132: 970-977, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30965077

RESUMO

Polysaccharides are a major class of biomacromolecules. Their bioactivities depend on chemical structure, which includes monosaccharide composition, linkages below sugar residues, and solution conformation. Many researchers report that chemical modifications of polysaccharides lead to a significantly increase in the structural diversity, promoting bioactivity and even add new bioactivities, including antioxidant and anti-tumor properties as well as anticoagulant and immunoregulatory activities. This paper reviews the recent progress of chemical modification of polysaccharides, including i) the common synthetic methods of chemical modification; ii) their structural characterization; iii) their bioactivities; and iv) the structure activity relationships of these modified polysaccharides. This review also suggests future directions for researchers and new applications for chemically modified polysaccharide derivatives in the pharmaceutical and food industries.


Assuntos
Polissacarídeos/química , Polissacarídeos/síntese química , Animais , Técnicas de Química Sintética , Humanos , Polissacarídeos/farmacologia , Relação Estrutura-Atividade
3.
Int J Biol Macromol ; 121: 1005-1010, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30342120

RESUMO

Tremella fuciformis is an important edible mushroom that has been widely cultivated and used as food and medicinal ingredient in traditional Chinese medicine. In the past decades, many researchers have reported that T. fuciformis polysaccharides (TPS) possess various bioactivities, including anti-tumor, immunomodulatory, anti-oxidation, anti-aging, repairing brain memory impairment, anti-inflammatory, hypoglycemic and hypocholesterolemic. The structural characteristic of TPS has also been extensively investigated using advanced modern analytical technologies such as NMR, GC-MS, LC-MS and FT-IR to dissect the structure-activity relationship (SAR) of the TPS biomacromolecule. This article reviews the recent progress in the extraction, purification, structural characterization and applications of TPS.


Assuntos
Basidiomycota/química , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/farmacologia , Animais , Polissacarídeos Fúngicos/isolamento & purificação , Humanos
4.
BJU Int ; 119(4): 612-618, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27862806

RESUMO

OBJECTIVE: To compare the safety and efficacy of fluoroscopic guidance (FG), total ultrasonographic guidance (USG), and combined ultrasonographic and fluoroscopic guidance (CG) for percutaneous renal access in mini-percutaneous nephrolithotomy (mini-PCNL). PATIENTS AND METHODS: The present study was conducted between July 2014 and May 2015 as a prospective randomised trial at the First Affiliated Hospital of Guangzhou Medical University. In all, 450 consecutive patients with renal stones of >2 cm were randomised to undergo FG, USG, or CG mini-PCNL (150 patients for each group). The primary endpoints were the stone-free rate (SFR) and blood loss (haemoglobin decrease during the operation and transfusion rate). Secondary endpoints included access failure rate, operating time, and complications. S.T.O.N.E. score was used to document the complexity of the renal stones. The study was registered at http://clinicaltrials.gov/ (NCT02266381). RESULTS: The three groups had similar baseline characteristics. With S.T.O.N.E. scores of 5-6 or 9-13, the SFRs were comparable between the three groups. For S.T.O.N.E. scores of 7-8, FG and CG achieved significantly better SFRs than USG (one-session SFR 85.1% vs 88.5% vs 66.7%, P = 0.006; overall SFR at 3 months postoperatively 89.4% vs 90.2% vs 69.8%, P = 0.002). Multiple-tracts mini-PCNL was used more frequently in the FG and CG groups than in the USG group (20.7% vs 17.1% vs 9.5%, P = 0.028). The mean total radiation exposure time was significantly greater for FG than for CG (47.5 vs 17.9 s, P < 0.001). The USG had zero radiation exposure. There was no significant difference in the haemoglobin decrease, transfusion rate, access failure rate, operating time, nephrostomy drainage time, and hospital stay among the groups. The overall operative complication rates using the Clavien-Dindo grading system were similar between the groups. CONCLUSIONS: Mini-PCNL under USG is as safe and effective as FG or CG in the treatment of simple kidney stones (S.T.O.N.E. scores 5-6) but with no radiation exposure. FG or CG is more effective for patients with S.T.O.N.E. scores of 7-8, where multiple percutaneous tracts may be necessary.


Assuntos
Fluoroscopia/métodos , Cálculos Renais/cirurgia , Litotripsia , Procedimentos Cirúrgicos Minimamente Invasivos , Nefrostomia Percutânea , Ultrassonografia/métodos , Analgésicos/uso terapêutico , Feminino , Humanos , Cálculos Renais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
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