检索结果-南通市图书馆

Degradation of duloxetine: Identification of transformation products by UHpLC-ESI(+)-HRMS/MS,in silico toxicity and wastewater analysis

引用

Journal of Environmental Sciences 2019年第8期31卷 113-123页

作者： Rodrigo A.Osawa ana p.carvalho Olinda C.Monteiro M.Conceicao Oliveira M.Helena Florêncio Centro de Química e Bioquímica Faculdade de Ciências Universidade de Lisboa Laboratório de FTICR e Espectrometria de Massa Estrutural Faculdade de Ciências Universidade de Lisboa Centro de Química Estrutural Instituto Superior Técnico Universidade de Lisboa

Duloxetine(DUL), an antidepressant drug, has been detected in surface water and wastewater effluents, however, there is little information on the formation of its transformation products(Tps). In this work, hydrolysis, photodegradation(UV irradiation) and chlorination experiments were performed on spiked distillated water, under controlled experimental conditions to simulate abiotic processes that can occur in the environment and wastewater treatment plants(WWTps). Eleven Tps, nine from reaction with UV light and two from chlorine contact, were formed and detected by ultra-high performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, and nine of them had their chemical structures elucidated upon analyses of their fragmentation patterns in MS/MS spectra. The formation and degradation of the Tps were observed. The parent compound was completely degraded after30 min in photodegradation and after 24 hr in chlorination. Almost all Tps were completely degraded in the experiments. The ecotoxicity and mutagenicity of the Tps were predicted based on several in silico models and it was found that a few of these products presented more ecotoxicity than DUL itself and six Tps showed positive mutagenicity. Finally, wastewater samples were analyzed and DUL and one Tp, possibly formed by chlorination process, were detected in the effluent, which showed that WWTp not only did not remove DUL, but also formed a Tp.

关键词： High resolution mass spectrometry Duloxetine Degradation processes Transformation products Wastewater analysis In silico toxicity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

引用

Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra carvalho ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 Gpa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)Gpa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Robotic Surgery: An Effective Treatment Option for Epiphrenic Diverticulum Associated with Nutcracker Esophagus

引用

Surgical Science 2024年第1期15卷 1-6页

作者： Augusto Tinoco Gilberto carvalho Leonardo Tinoco ana paula Quintão Department of Digestive Surgery Hospital S&#227o Jos&#233 do Ava&#237 Itaperuna Brazil

Background: Epiphrenic Diverticulum is frequently associated with esophageal motility disorders, such as nutcrackers esophagus. The diagnosis is usually made using imaging studies such as a Barium esophagogram, and esophageal manometry. Surgical treatment options for epiphrenic diverticulum and EN include diverticulectomy and wide myotomy. Aim: The resection of three epiphrenic diverticula and extensive myotomy were performed by robotic thoracoscopy uneventfully. Case presentation: A 65-year-old female complaining of dysphagia for solid foods, Chest pain and regurgitation. Esophagogastroduodenoscopy (EDG) with difficulty in advancing the endoscope at 25 cm and demonstrating an ED, no hiatal hernia and normal stomach and duodenum. Barium Esophagogram showed multiple diverticula and tortuosity throughout the esophagus. Conclusion: With robotic surgery, surgeons can perform highly precise operations with enhanced 3D vision and control. Through this cutting-edge approach, the treatment of ED associated with EN can be drastically changed, promising better outcomes for patients.

关键词： Robotic Surgery Myotomy Nutcracker Esophagus Epiphrenic Diverticulum

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Natural Mg silicates with different structures and morphologies: Reaction with K to produce K2MgSiO4 catalyst for biodiesel production

引用

International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 46-54页

作者： Fabiane carvalho Ballotin Mayra Nascimento Sara Silveira Vieira Alexandre carvalho Bertoli Ottávio Carmignano ana paula de carvalho Teixeira Rochel Montero Lago Departamento de Química Universidade Federal de Minas GeraisBelo HorizonteBrasil Doutorado Inovação/Mineradora pedras Congonhas Universidade Federal de Minas Gerais31270-901 Belo Horizonte-MGBrazil

In this work, different magnesium silicate mineral samples based on antigorite, lizardite, chrysotile(which have the same general formula Mg3Si2O5(OH)4), and talc(Mg3Si4O10(OH)2) were reacted with KOH to prepare catalysts for biodiesel production. Simple impregnation with 20 wt% K and treatment at 700–900°C led to a solid-state reaction to mainly form the K2MgSiO4 phase in all samples. These results indicate that the K ion can diffuse into the different Mg silicate structures and textures, likely through intercalation in the interlayer space of the different mineral samples followed by dehydroxylation and K2MgSiO4 formation. All the materials showed catalytic activity for the transesterification of soybean oil(1:6 of oil : methanol molar ratio, 5 wt% of catalyst, 60°C). However, the best results were obtained for the antigorite and chrysotile precursors, which are discussed in terms of mineral structure and the more efficient formation of the active phase K2MgSiO4.

关键词： silicate serpentinite lizardite antigorite talc chrysotile biodiesel

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermal and Mechanical properties of Thermoplastic Starch and poly(Vinyl Alcohol-Co-Ethylene)Blends

引用

Journal of Renewable Materials 2019年第3期7卷 245-252页

作者： ana Clara Lancarovici Alves Rafael Grande Antonio José Felix carvalho Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone110013563-120Sao Carlos-SP-Brazil

The interest in thermoplastic starch(TpS)as a substitute material to replace conventional thermoplastics continues especially due its biodegradability,availability,low cost and because it is obtained from renewable ***,its poor mechanical properties and its high sensitivity to humidity have limited its use in several ***,the copolymer poly(ethylene-co-vinyl alcohol)(EVOH),with two different ethylene contents,27 and 44 mol%were blended with TpS by extrusion in order to overcome these *** obtained blends were characterized by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),mechanical tensile testing,Scanning Electron Microscopy(SEM)and moisture absorption *** addition of EVOH copolymer did not significantly changed the thermal stability of TpS,however it increased the tensile strength in 65%when compared to *** morphology of the blends did not showed two distinct phases,an indication of miscibility or partial miscibility of the components.A decrease of moisture absorption was obtained by the addition of EVOH and is more pronounced for the EVOH with 44% of ethylene.

关键词： Thermoplastic starch EVOH polymer blends thermal properties of polymers mechanical properties of polymers

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Selective silencing of 2Cys and type-ⅡB peroxiredoxins discloses their roles in cell redox state and stress signaling

引用

Journal of Integrative plant Biology 2015年第6期57卷 591-601页

作者： patrícia Vidigal ana Montserrat Martin-Hernandez Cèlia Guiu-Aragonés Sara Amncio Luísa carvalho Departamento de Recursos Naturais Ambiente e Território (DRAT)/Centro de Botanica Aplicada à Agricultura (CBAA)Institute of AgronomyUniversity of Lisbon Institut de Recercai Tecnologia Agroalimentàries (IRTA) Centre for Research in Agricultural Genomics (CSIC-IRTA-UAB-UB) Campus Universitat Autonoma de Barcelona (UAB)Edificio Center for Research in Agricultural Genomics (CRAG)

peroxiredoxins （prx） catalyse the reduction of hydrogen peroxide （H2O2） and, in association with catalases and other peroxidases, may participate in signal transduction by regulating intercel ular H2O2 concentration that in turn can control gene transcription and cel signaling. Using virus-induced-gene-silencing （VIGS）, 2-Cys peroxiredoxin （2Cysprx） family and type-II peroxiredoxin B （prxI B） gene were silenced in Nicotiana benthamiana, to study the impact that the loss of function of each prx would have in the antioxidant system under control （22℃） and severe heat stress conditions （48 ℃）. The results showed that both prxs, although in different organel es, influence the regeneration of ascorbate to a significant extent, but with different purposes. 2Cysprx affects abscisic acid （ABA） biosynthesis through ascorbate, while prxIIB does it probably;through the xanthophyl cycle. Moreover, 2Cysprx is key in H2O2 scavenging and in consequence in the regulation of ABA signal-ing downstream of reactive oxygen species and prxIIB provides an important assistance for H2O2 peroxisome scavenges.

关键词： 2-Cys peroxiredoxin abscisic acid ascorbate heat stress hydrogen peroxide peroxisome type-Ⅱ peroxiredoxin B

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Appropriateness of the study of iron deficiency anemia prior to referral for small bowel evaluation at a tertiary center

引用

World Journal of Gastroenterology 2017年第24期23卷 4444-4453页

作者： Jaime pereira Rodrigues Rolando pinho Joana Silva ana ponte Mafalda Sousa Joao Carlos Silva Joao carvalho Department of Gastroenterology Centro Hospitalar Vila Nova de Gaia/EspinhoRua Conceicao FernandesVila Nova de Gaia

To evaluate the adequacy of the study of iron deficiency anemia (IDA) in real life practice prior to referral to a gastroenterology department for small bowel evaluation. METHODSAll consecutive patients referred to a gastroenterology department for small bowel investigation due to iron deficiency anemia, between January 2013 and December 2015 were included. Both patients referred from general practitioners or directly from different hospital departments were selected. Relevant clinical information regarding prior anemia workup was retrospectively collected from medical records. An appropriate pre-referral study was considered the execution of esophagogastroduodenoscopy (EGD) with Helicobacter pylori (H. pylori) investigation, colonoscopy with quality standards (recent, total and with adequate preparation) and celiac disease (CD) screening (through serologic testing and/or histopathological investigation). RESULTSA total of 77 patients (58.4% female, mean age 67.1 ± 16.7 years) were included. Most (53.2%) patients were referred from general practitioners, 41.6% from other hospital specialties and 5.2% directly from the emergency department. The mean pre-referral hemoglobin concentration was 8.8 ± 2.0 g/dL and the majority of anemias had microcytic (71.4%) and hypochromic (72.7%) characteristics. 77.9% of patients presented with an incomplete pre-referral study: EGD in 97.4%, with H. pylori investigation in 58.3%, colonoscopy with quality criteria in 63.6%, and CD screening in 24.7%. patients with an appropriate study at the time of referral were younger (48.7 ± 17.7 vs 72.3 ± 12.3 years, p patients, with a more frequent evaluation in patients with a quality colonoscopy at referral (78.6% vs 23.8%); p pper and lower ga

关键词： Iron deficiency anemia Colonoscopy Celiac disease Esophagogastroduodenoscopy Helicobacter pylori Small bowel

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Formation of DNA Strand Breaks in peripheral Lymphocytes of Rats After Exposure to Natural Sunlight

引用

Biomedical and Environmental Sciences 2012年第2期25卷 245-249页

作者： Dorival Mendes RODRIGUES-JUNIOR ana Amélia de carvalho MELO Benedito Borges da SILVA pedro Vitor LOpES-COSTA Department of Biology Federal University of Piaui-TeresinaPiauiBrazil Department of Gynecology Federal University of Piaui-TeresinaPiauiBrazil

Objective This paper aims to evaluate the genotoxicity in peripheral blood lymphocytes of rats after exposure to sunlight at different time points of day in a tropical region of Brazil（5oS,42oW）.Materials and Methods Thirty Wistar-Hannover rats,three months old,were randomly divided into three groups of 10 animals each：Group I [control,without exposure to ultraviolet（UV） radiation],Group II（exposed to sunlight during 08：00 *** 10：00 a.m.）,and Group III（exposed to sunlight during 10：00 *** 12：00 a.m.）.After a week of exposure,peripheral blood samples were taken from the tail of these animals to prepare smears on two slides per *** 24 h after exposure to sunlight in Group III,a new collection was obtained to observe the repair *** alkaline comet assay was used in this study to evaluate the genotoxic activity of sunlight（p0.05）.Results There was no statistical difference between Group I and II（p=0.672）.On the other hand,the exposure to sunlight in Group III showed genotoxic action in comparison to the other groups（p0.0001）.Also,there was no significant repair in Group III R（p=0.407）.Conclusion This study has shown a genotoxic potential of sunlight（UVA-B） in lymphocytes of mammals from 10：00 *** 12：00 a.m.,due to a higher intensity of UV in this tropical region.

关键词： Comet assay DNA damage Rats Sunlight Ultraviolet radiation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thiopurine-methyltransferase variants in inflammatory bowel disease:prevalence and toxicity in Brazilian patients

引用

World Journal of Gastroenterology 2014年第12期20卷 3327-3334页

作者： ana Teresa p.carvalho Barbara C Esberard Renata S B Fróes Davy C M Rapozo ana B Grinman Tatiana A Simo Juliana C V C Santos Antonio José V Carneiro Luis Felipe Ribeiro-pinto Heitor S p de Souza Disciplina de Gastroenterologia e Endoscopia Digestiva Universidade do Estado do Rio de Janeiro programa de Carcinogênese Molecular Instituto Nacional de Cancer Laboratório de Toxicologia e Biologia Molecular Universidade do Estado do Rio de Janeiro Servi?o de Gastroenterologia Departamento de Clínica MédicaUniversidade Federal do Rio de Janeiro

AIM: To analyze the prevalence of thiopurine-methyltransferase (TpMT) genotypes and their association with drug toxicity in inflammatory bowel disease (IBD) patients from southeastern Brazil.

关键词： Inflammatory bowel disease Thiopurine-methyl-transferase Azathioprine Drug toxicity pancreatitis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Distal renal tubular acidosis:genetic causes and management

引用

World Journal of pediatrics 2019年第5期15卷 422-431页

作者： Sílvia Bouissou Morais Soares Luiz Alberto Wanderley de Menezes Silva Flávia Cristina de carvalho Mrad ana Cristina Simoes e Silva Interdisciplinary Laboratory of Medical Investigation Faculty of MedicineFederal University of Minas Gerais(UFMG)Av.Prof.Alfredo Balena190Room#281Belo HorizonteMG 30130-100Brazil pediatric Nephrology Unit Faculty of MedicineUFMGBelo HorizonteBrazil

Background Distal renal tubular acidosis(dRTA)is a kidney tubulopathy that causes a state of normal anion gap metabolic acidosis due to impairment of urine *** review aims to summarize the etiology,pathophysiology,clinical findings,diagnosis and therapeutic approach of dRTA,with emphasis on genetic causes of *** sources Literature reviews and original research articles from databases,including pubMed and Google *** searching was performed to identify additional studies about *** dRTA is characterized as the dysfunction of the distal urinary acidification,leading to metabolic *** pediatric patients,the most frequent etiology of dRTA is the genetic alteration of genes responsible for the codification of distal tubule channels,whereas,in adult patients,dRTA is more commonly secondary to autoimmune diseases,use of medications and *** with dRTA exhibit failure to thrive and important laboratory alterations,which are used to define the *** oral alkali and potassium supplementation can correct the biochemical defects,improve clinical manifestations and avoid nephrolithiasis and *** dRTA is a multifactorial disease leading to several clinical *** and laboratory alterations can be corrected by alkali replacement therapy.

关键词： Renal tubular acidosis Distal tubule physiology Metabolic acidosis Gene mutations proton pump

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：