检索结果-南通市图书馆

Molecular aspects of intestinal calcium absorption

World Journal of Gastroenterology 2015年第23期21卷 7142-7154页

作者： gabriela Diaz de Barboza Solange Guizzardi Nori Tolosa de Talamoni Cátedra de Bioquímica y Biología Molecular Facultad de Ciencias Médicas Universidad Nacional de Córdoba

Intestinal Ca2+ absorption is a crucial physiological process for maintaining bone mineralization and Ca2+ homeostasis. It occurs through the transcellular and paracellular pathways. The first route comprises 3steps: the entrance of Ca2+ across the brush border membranes(BBM) of enterocytes through epithelial Ca2+ channels TRPV6, TRPV5, and Cav1.3; Ca2+ movement from the BBM to the basolateral membranes by binding proteins with high Ca2+ affinity(such as CB9k); and Ca2+ extrusion into the blood. Plasma membrane Ca2+ ATPase(PMCA1b) and sodium calcium exchanger(NCX1) are mainly involved in the exit of Ca2+ from enterocytes. A novel molecule, the 4.1R protein, seems to be a partner of PMCA1 b, since both molecules colocalize and interact. The paracellular pathway consists of Ca2+ transport through transmembrane proteins of tight junction structures, such as claudins 2, 12, and 15. There is evidence of crosstalk between the transcellular and paracellular pathways in intestinal Ca2+ transport. When intestinal oxidative stress is triggered, there is a decrease in the expression of several molecules of both pathways that inhibit intestinal Ca2+ absorption. Normalization of redox status in the intestine with drugs such as quercetin, ursodeoxycholic acid, or melatonin return intestinal Ca2+ transport to control values. Calcitriol [1,25(OH)2D3] is the major controlling hormone of intestinal Ca2+ transport. It increases the gene and protein expression of most of the molecules involved in both pathways. PTH, thyroid hormones, estrogens, p ro l a c t i n, g ro w t h h o r m o n e, a n d g l u c o c o r t i c o i d s apparently also regulate Ca2+ transport by direct action, indirect mechanism mediated by the increase of renal 1,25(OH)2D3 production, or both. Different physiological conditions, such as growth, pregnancy, lactation, and aging, adjust intestinal Ca2+ absorption according to Ca2+ demands. Better knowledge of the molecular details of intestinal Ca2+ absorption could l

关键词： Intestinal Ca2+ absorption Transcellularpathway Paracellular route 1,25(OH)2D3 PTH Prolactin Estrogen Lactation Pregnancy Aging

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

Serum 25-hydroxyvitamin D concentration and inflammatory bowel disease characteristics in Romania

引用

World Journal of Gastroenterology 2014年第9期20卷 2392-2396页

作者： gabriela Dumitrescu Catalina Mihai Mihaela Dranga Cristina Cijevschi Prelipcean Department of Medical Sciences Grigore T. Popa University of Medicine and Pharmacy Iasi 700115 Romania

AIM: To describe the relationship between vitamin D levels and inflammatory bowel disease (IBD) characteristics in northeastern Romanian patients.

关键词： Inflammatory bowel disease, Vitamin D level, Northeastern Romania, Crohn’ s disease activity, Seasonality

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

Catchment soils as a factor of trace metal accumulation in sediments of the reservoir Klingenberg(eastern Ore Mountains, Germany)

引用

Journal of Environmental Sciences 2019年第12期31卷 1-14页

作者： Jens Hahn Christian Opp Raphael Ganzenmuller Anntke Ewert Birgit Schneider Nina Zitzer gabriela Laufenberg Philipps-University of Marburg Working Group for Hydro-and Soil GeographyDeutschhausstr.1035037 MarburgGermany University of Leipzig Institute of GeographyPhysical GeographyJohannisallee 19a04103 LeipzigGermany Philipps-Uniuersity o/Marbitrg Mass SpectrometryMarbacher Weg 6-1035037 MarburgGermany

The release and accumulation dynamics of trace metals in soils and aquatic sediments were exemplarily investigated in the catchment area of the Reservoir Klingenberg(Germany).Catchment soils were examined for mobilizable and total concentrations of arsenic(As),cadmium(Cd),chrome(Cr),iron(Fe),manganese(Mn),nickel(Ni),lead(Pb),and zinc(Zn)and compared with trace metal quantities accumulated in riverbed and reservoir *** comparison of all samples showed relatively small variations of Cr(7.96–46.0 mg/kg),Fe(7.79–40.4 g/kg),and Ni(6.06–56.5 mg/kg),while stronger differences were found for As(11.2–164 mg/kg),Cd(0.14–30.5 mg/kg),Mn(0.08–1.84 g/kg),Pb(20.7–183 mg/kg),and Zn(69.1–916 mg/kg).The catchment soils were slightly enriched by Cd,Pb,and *** Cd and Zn were characterized by large mobilizable *** mean trace metal concentrations in riverbed sediments were higher than in catchment soils,while reservoir sediments accumulated the highest amounts of the analyzed *** enrichment of trace metals in reservoir sediments was generally determined by the sedimentation of fine particles,while the distribution of As,Fe,and Mn was additionally impacted by redox *** Cd and Zn,which in comparison were most enriched in riverbed and reservoir sediments,a significant release from soils by leaching processes was *** accumulation of As and Pb in reservoir sediments was influenced to a greater extent by soil erosion and by anthropogenic or chalcogen sources in the catchment.

关键词： Trace metals Exchangeable forms Soil Sediment Catchment Sources

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

Improved frost forecast using machine learning methods

引用

Artificial Intelligence in Geosciences 2023年第1期4卷 164-181页

作者： Jos´e Roberto Rozante Enver Ramirez Diego Ramirez gabriela Rozante Center for Weather Forecast and Climate Studies National Institute for Space ResearchCachoeira PaulistaSPBrazil University of Sao Paulo(EEL/USP) LorenaSPBrazil Sao Paulo State University(UNESP) BauruSPBrazil

Frosts are one of the atmospheric phenomena with one of the larger negative effects on the agricultural sector in the southern region of Brazil,therefore,an earlier forecast can minimize their *** the present work,artificial neural networks(ANNs)techniques were applied in order to improve the predicting capabilities of frost events in southern *** the study,two multilayer perceptron(MLP)ANNs were built,one with ADAM optimizer and the other with *** input parameters MLP-ANNs were numerical predictions of the Eta *** ANNs were trained using four years(2012-2015),while validation and testing were performed using 2016 and 2017,*** episode of frost that occurred on May 21st,2018,related to an intense cold air mass,was also utilized to evaluate the performance of the *** best configurations(topologies and hyperparameters)of the ANNs were identified through experiments,using the highest accuracy obtained during the validation period as a *** results of the ANNs with ADAM and SGD optimizers were compared with the predictions of the Eta *** the case study,an additional comparison against the operational frost index(IG)from the National Institute for Space Research(INPE)was also *** performance of both ANNs(properly configured)with ADAM and SGD optimizers are comparable one to the *** both are significantly better compared to the Eta *** ANNs were able to drastically reduce the underestimation trends of frost events caused by the warm bias of the Eta *** ANNs also indicated more satisfactory performances when compared to the INPE *** general,the ANNs were able to identify deficiencies in Eta predictions,and consequently improve their *** this sense,the use of ANNs to predict frost events can be a very useful tool in an operational environment.

关键词： Frost Artificial neural networks Multilayer perceptron frost index Deep learning

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

Promiscous female Euxesta eluta derive nutrients for ovarian development by expelling and consuming ejaculates

引用

Insect Science 2020年第3期27卷 545-557页

作者： Solana Abraham Gisela Castillo Viviana Diaz Guido Van Nieuwenhove gabriela Murua Juan Rull Laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales(LIEMEN) PROIMI-BiotecnologiaCONICETTucumanArgentina Fundacion Miguel Ullo Instde EntomologiaDepto ZoologiaMiguel Lillo 251San Miguel de TucumanTucumanArgentina Facultad de Ciencias Naturales e I.M.L Universidad Nacional de TucumanSan Miguel de TucumanTucumanArgentina Estacion Experimental Agroindustrial Obispo Colombres(EEAOC)_ITANOA CONICET TucumanArgentina

Seminal gifts range from important material donations to items that provide little direct benefit to ***,female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after *** evolution and function of this peculiar behavior are currently *** performed a series of experiments aimed to:determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption,if males suffer a fitness cost from supplying females with ejaculates,and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior *** revealed that protein deprived *** females derive nutrients for ovarian development through consumption of ejaculates of protein fed *** seminal products affecting survival appear to be transferred in the consumed ***,ovarian development,in contrast to testes growth,occurs in detriment of *** preferred to mate with protein fed males,yet sperm retention in spermathecae was extremely rare after a single *** finding suggests that females could be exerting post copulatory control.A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential.

关键词： anautogeny polyandry postcopulatory female control seminal gifts sperm storage

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

Acoustic radiation force imaging sonoelastography for noninvasive staging of liver fibrosis

引用

World Journal of Gastroenterology 2009年第44期15卷 5525-5532页

作者： Carmen Fierbinteanu-Braticevici Dan Andronescu Radu Usvat Dragos Cretoiu Cristian Baicus gabriela Marinoschi Medical Clinic and Gastroenterology University Hospital050094 BucharestRomania Department of Cellular and Molecular Medicine "Carol Davila" University of Medicine and Pharmacy050094 BucharestRomania Department of Internal Medicine and Réseau d'Epidémiologie Clinique International Francophone (RECIF) Colentina Hospital020125 BucharestRomania Institute of Mathematical Statistics and Applied Mathematics 050711 BucharestRomania

AIM:To investigate the diagnostic accuracy of acoustic radiation force impulse (ARFI) imaging as a noninvasive method for the assessment of liver fibrosis in chronic hepatitis C (CHC) ***:We performed a prospective blind com-parison of ARFI elastography,APRI index and FibroMax in a consecutive series of patients who underwent liver biopsy for CHC in University Hospital Bucharest. His-topathological staging of liver fibrosis according to the METAVIR scoring system served as the reference. A to-tal of 74 patients underwent ARFI elastography,APRI index,FibroMax and successful liver biopsy. RESULTS:The noninvasive tests had a good correlation with the liver biopsy results. The most powerful test in predicting fibrosis was ARFI elastography. The diagnostic accuracy of ARFI elastography,expressedas area under receiver operating characteristic curve (AUROC) had a validity of 90.2% (95% CI AUROC = 0.831-0.972,P < 0.001) for the diagnosis of significant f ibrosis (F ≥ 2). ARFI sonoelastography predicted even better F3 or F4 fibrosis (AUROC = 0.993,95% CI = 0.979-1).CONCLUSION:ARFI elastography had very good accuracy for the assessment of liver fibrosis and was superior to other noninvasive methods (APRI Index,FibroMax) for staging liver fibrosis.

关键词： Elasticity imaging techniques Hepatitis C Liver biopsy Liver fibrosis

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

Effect of a Hybrid Zinc Stearate-Silver System on the Properties of Polylactide and Its Abiotic and the Biotic Degradation and Antimicrobial Activity Thereof

引用

Chinese Journal of Polymer Science 2018年第8期36卷 925-933页

作者： gabriela Jandikova Petra Stoplova Antonio Di Martino Petr Stloukal Pavel Kucharczyk Michal Machovsky Vladimir Sedlarik Centre of Polymer Systems University Institute Tomas Bata University in Zlin tr. Tomas Bati 5678 760 O1 Zlin Czech Republic

This work investigates the degradation and properties of a thermoplastically prepared composite comprising a polylactide/ hybrid zinc stearate-silver system. The influence of the zinc stearate-silver system on the properties of the composite is investigated by electron microscopy, differential scanning calorimetry and tensile tests. Furthermore, the antimicrobial activities of the systems are examined. The degradation behaviour of the composites is studied in both abiotic and biotic （composting） environments at an elevated temperature of 58 ℃. The results reveal good dispersion of the additive in the PLA matrix, a stabilizing effect exerted by the same on the polylactide matrix during processing, and slight reduction in glass transition temperature. The zinc stearate-silver component also reduces brittleness and extends elongation of the composite. Abiotic hydrolysis is not significantly affected, which is in contrast with pure PLA, although mineralization during the early stage of biodegradation increases noticeably. The composite exhibits antimicrobial activity, even at the lowest dosage of the zinc stearate/silver component （1 wt%）. Moreover, Ag and Zn contents were found to be present in the composite during abiotic hydrolysis, which was demonstrated by minimal diffusion of Ag ions from the matrix and very extensive washing of compounds that contained Zn.

关键词： Polylactide Composite Biodegradation Zinc stearate Silver Antimicrobial

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

Oxidative stress in the hydrophilic medium of algae and invertebrates

引用

BIOCELL 2016年第1期40卷 35-38页

作者： gabriela MALANGA PAULA MARIELA GONZALEZ JUAN MANUEL OSTERA SUSANA PUNTARULO Instituto de Bioquímica y Medicina Molecular(IBIMOL)-Universidad de Buenos Aires(UBA) CONICETFisicoquímicaFacultad de Farmacia y BioquímicaJunín 956(C1113AAD)Buenos Aires.Argentina.

The harmful effects of the reactive species may be due to the increase in their steady state concentration either by the enhancement of their production rates and/or the decrease of their consumption rate by antioxidant *** ascorbyl radical(A^(·))can be considered as a final product of radical oxidative transformations of ascorbate(AH^(-)).The ratio A^(·)content/AH^(-)content(A^(·)/AH^(-))has been widely used as an interesting tool to estimate mild to moderate oxidative transformations,providing a quick and simple method of diagnosis of stress in the hydrophilic cellular *** aim of this work was to summarize studies on the cellular oxidative condition in algae and invertebrates by assessing the A^(·)/AH^(-)ratio under environmentally changing *** use of indices of oxidative stress increasingly sensitive and,somewhat more specific,can bring a new light to the still unknown world of oxidative responses in marine organisms.

关键词： algae ascorbyl/ascorbate ratio invertebrates oxidative stress

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

Transcriptional Programs Related to Phytochrome A Function in Arabidopsis Seed Germination

引用

Molecular Plant 2013年第4期6卷 1261-1273页

作者： Silvia E. Ibarra gabriela Auge Rodolfo A. Sanchez Javier F. Botto IFEVA Facultad de Agronomfa Universidad de Buenos Aires y Consejo Nacional de Investigaciones Cientificas y Tecnicas Av. San Martin 4453 C1417DSECiudad de Buenos Aires Argentina

In Arabidopsis seeds, germination is promoted only by phytochromes, principally phytochrome B （phyB） and phytochrome A （phyA）. Despite the abundant information concerning the molecular basis of phyB signaling downstream of PIF1/PIL5, the signaling network inducing germination by phyA is poorly known. Here, we describe the influence of phyA on the transcriptome of Arabidopsis seeds when germination is induced by a far-red （FR） pulse. The expression of 11% of the genome was significantly regulated by phyA. Most of the genes were up-regulated and the changes noted late （i.e. 5 h after a FR pulse）, whereas changes in down-regulated genes were more abundant earlier （i.e. 0.5 h after a FR pulse）. Auxin- and GA-associated elements were overrepresented in the genes that were modified by phyA. A significant number of genes whose expression was affected by phyA had not been previously reported to be dependent on PIL5. Among them, homozygotic mutant seeds of MYB66, a SAUR-like protein, PIN7, and GASA4 showed an impaired promo- tion of germination by phyA. Natural variation at the transcriptional level was found in early signaling and GA metabolic genes, but not in ABA metabolic and expansin genes between Columbia and Landsberg erecta accessions. Although phyA and phyB/PIL5 signaling pathways share some molecular components, our data suggest that phyA signaling is partially independent of PIL5 when germination is promoted by very low fluences of light.

关键词： transcriptome germination light Arabidopsis seeds PIF1/PIL5 phytochrome A (phyA) phytochrome B (phyB).

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

Finding a role for cancer vaccines in pancreatic cancer:a model of resilience

引用

Hepatobiliary Surgery and Nutrition 2022年第1期11卷 115-118页

作者： Gentry King Steven Green E.gabriela Chiorean Department of Medicine Division of Medical OncologyUniversity of Washington School of MedicineSeattleWAUSA Clinical Research Division Fred Hutchinson Cancer Research CenterSeattleWAUSA

Neoadjuvant chemotherapy with folinic acid,5-fluorouracil,irinotecan and oxaliplatin(FOLFIRINOX)or gemcitabine plus nab-paclitaxel(Gem-nabP)for 4 to 6 months,potentially followed by chemoradiotherapy and an attempt for surgical resection for select patients,represents the multidisciplinary care standard for borderline resectable(BRPC)and locally advanced pancreatic ductal adenocarcinoma(LAPC)patients with good performance status(1,2).With neoadjuvant therapy,resection rates average 65%and survival ranges from 22-29 months for BRPC,whereas LAPC patients have resection rates of 15-20%and survival of 16-24 months,respectively(3-5).

关键词： chemotherapy cancer patients

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：