检索结果-南通市图书馆

Kainate receptors in the CA2 region of the hippocampus

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2023年第2期18卷 320-321页

作者： Yuniesky Andrade-Talavera Antonio Rodríguez-Moreno laboratorio de Neurociencia Celulary Plasticidad Departamento de FisiologíaAnatomía y Biología CelularUniversidad Pablo de OlavideSevillaSpain

The hippocampus is involved in important brain functions such as learning and memory,spatial navigation,fear processing,and social behavior(Dudek et al,2016).The most prominent areas of the hippocampus are typically denoted as the dentate gyrus and the three areas of the cornu ammonis(CA1,CA2,and CA3).Discovered by Lorente de Nó(1934),the CA2 region of the hippocampus is a relatively small area interposed between CA3 and CA1 that forms the nexus linking the input of the entorhinal cortex to the output of CA1(Chevaleyre and Siegelbaum,2010).

关键词： CA2 cortex linking

Electrochemical reduction of Cr(Ⅵ)in the presence of sodium alginate and its application in water purification

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2021年第3期33卷 304-312页

作者： Bryan Butter Paola Santander Guadalupe del CPizarro Diego POyarzún Federico Tasca Julio Sánchez Facultad de Química y biología Universidad de Santiago de ChileUSACHCasilla 40Correo 33SantiagoChile departamento de Química Universidad Tecnológica MetropolitanaJ.P.Alessandri 1242SantiagoChile laboratorio de Nanotecnología Recursos Naturales y Sistemas ComplejosFacultad de Ciencias NaturalesUniversidad de AtacamaCopayapu 485CopiapóChile

Chromium(Cr)is used in many manufacturing processes,and its release into natural waters is a major environmental problem *** concentrations of Cr(Ⅵ)are toxic to human health and living organisms due to the carcinogenic and mutagenic nature of this *** work examined the conversion of Cr(Ⅵ)to Cr(Ⅲ)via electrochemical reduction using gold electrode in an acidic sodium alginate(SA)solution and subsequent removal of the produced Cr(Ⅲ)-SA by the polymer-enhanced ultrafiltration(PEUF)technique.A solution of SA in nitric acid was used both as an electrolytic medium during the voltammetric measurements and bulk electrolysis and as an extracting agent during the PEUF *** electroanalysis of Cr(Ⅵ)was performed by linear sweep voltammetry in the presence of acidic SA solution to study its voltammetric behavior as a function of the Cr(Ⅵ)concentration,pH,presence of Cr(Ⅲ),SA concentration and scan *** addition,the quantitative reduction of Cr(Ⅵ)to Cr(Ⅲ)was studied through the bulk electrolysis *** results showed efficient reduction with well-defined peaks at approximately 0.3 V ***/AgCl,using a gold working *** the pH increased,the reduction signal strongly decreased until its *** optimum SA concentration was 10 mmol/L,and it was observed that the presence of Cr(Ⅲ)did not interfere in the Cr(Ⅵ)*** the quantitative reduction by bulk electrolysis in the presence of acidic SA solution,it was possible to reduce all Cr(Ⅵ)to Cr(Ⅲ)followed by its removal via PEUF.

关键词： Alginate solution Chromium Electroanalytical chemistry Ultrafiltration Water purification

Eucalyptus grandis plantations:effects of management on soil carbon,nutrient contents and yields

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2020年第2期31卷 601-611页

作者： Diego Martin Sandoval Lopez Marcelo Fabian Arturi Juan Francisco Goya Carolina Alejandra Perez Jorge Luis Frangi laboratorio de Investigacion de sistemas Ecologicos y Ambientales(LISEA) Universidad Nacional de La PlataDiagonal 113 N°4691900 La PlataBuenos AiresArgentina

The expansion of fast-growing tree plantations is a worldwide process,with consequences on soil fertility and soil carbon *** results were found on the effects of afforestation with Eucalyptus on soil carbon and other nutrient *** discrepancies are usually caused by differences in climate,land use history,soil texture as well as by management related factors such as plantation age,number of rotations,method of establishment(plantation or coppice),harvest residue management and soil *** studied the effect of plantation age,number of rotations,and method of establishment on soils and plant nutrient concentrations in Eucalyptus grandis plantations in NE Argentina on different textured *** also determined if yields changed with nutrient variations in soils,and compared soils under plantations to soils under grasslands they ***-one *** stands of different ages,number of rotations and method of establishment were evaluated as well as eight grassland *** of carbon,nitrogen,phosphorus,potassium,calcium and magnesium were determined for soils and *** carbon and nitrogen decreased over the number of rotations and were more pronounced in soils with 50-60%sand than soils with>75%*** stands showed higher soil carbon and nitrogen levels than plantations,suggesting a negative effect of site preparation before planting on soil nutrient conservation,especially in fine-textured *** nutrient concentrations did not follow the trends observed for soil nutrients nor did they reflect nutrient *** was no evidence of decreased yields over successive *** carbon and nitrogen contents decrease when grasslands are replaced by *** plantations,and therefore a yield limitation may occur in a medium to long-term frame,especially in stands re-established for short-rotation *** residue management and site preparation must be specifically designed for improving so

关键词： Soil texture Grasslands Foliar nutrient concentrations Successive harvest Coppice Eucalyptus grandis

Progesterone for the treatment of central nervous system disorders: the many signaling roads for a single molecule

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第10期15卷 1846-1847页

作者： Susana Laura González Universidad de Buenos Aires Facultad de Medicina Departamento de Bioquímica Humana Buenos Aires laboratorio de Nocicepción y Dolor Neuropático Instituto de Biología y Medicina Experimental

Central nervous system(CNS)injuries and neurodegenerative diseases show a broad spectrum of common pathophysiological processes,including oxidative stress,neuroinflammation,excitotoxicity,demyelination and neurotransmission *** the past decades,valuable experimental investigations have helped to clarify the role and timing of these multiple molecular and cellular mechanisms in each of these particular disorders,which usually overlap and critically contribute to long-term ***,up to now,no definite cures or effective disease-modifying therapies are available for any of these *** has led to an active search of novel therapeutic approaches,including the repositioning of existing drugs for new indications,as a valid approach to promptly move candidate molecules to clinical trials.

关键词： injuries disorders drugs

Influence of dissolved organic matter character on mercury incorporation by planktonic organisms: An experimental study using oligotrophic water from Patagonian lakes

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2013年第10期25卷 1980-1991页

作者： María C.Diéguez Claudia P.Queimalios Sergio Ribeiro Guevara Mark Marvin-DiPasquale Carolina Soto Crdenas María A.Arribre laboratorio de Fotobiología INIBIOMA CONICET-UNComahue laboratorio de Fotobiolog INIBIOMA CONICET-UNComahue laboratorio de Anlisis por Activación Neutrónica Centro Atómico Bariloche CNEA United States Geological Survey laboratorio de Anlisis por Activacio Neutrónica Centro Atómico Bariloche CNEA

Ligands present in dissolved organic matter （DOM） form complexes with inorganic divalent mercury （Hg^2＋） affecting its bioavailability in pelagic food webs. This investigation addresses the influence of a natural gradient of DOM present in Patagonian lakes on the bioaccumulation of Hg^2＋（the prevailing mercury species in the water column of these lakes） by the algae Cryptomonas erosa and the zooplankters Brachionus calyciflorus and Boeckella antiqua. Hg^2＋ accumulation was studied through laboratory experiments using natural water of four oligotrophic Patagonian lakes amended with^197Hg^2＋. The bioavailability of Hg^2＋ was affected by the concentration and character of DOM. The entrance of Hg^2＋ into pelagic food webs occurs mostly through passive and active accumulation. The incorporation of Hg^2＋ by Cryptomonas, up to 27% of the Hg^2＋ amended, was found to be rapid and dominated by passive adsorption, and was greatest when low molecular weight compounds with protein-like or small phenolic signatures prevailed in the DOM. Conversely, high molecular weight compounds with a humic or fulvic signature kept Hg^2＋ in the dissolved phase, resulting in the lowest Hg^2＋ accumulation in this algae. In Brachionus and Boeckella the direct incorporation of Hg from the aqueous phase was up to 3% of the Hg^2＋ amended. The dietary incorporation of Hg^2＋ by Boeckella exceeded the direct absorption of this metal in natural water, and was remarkably similar to the Hg^2＋ adsorbed in their prey. Overall, DOM concentration and character affected the adsorption of Hg^2＋ by algae through competitive binding, while the incorporation of Hg^2＋ into the zooplankton was dominated by trophic or dietary transfer.

关键词： mercury dissolved organic matter plankton mercury incorporation Patagonian lakes Argentina

Progesterone effects on the oligodendrocyte linage: all roads lead to the progesterone receptor

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2019年第12期14卷 2029-2034页

作者： Ignacio Jure Alejandro F. de Nicola Florencia Labombarda laboratorio de Bioquímica Neuroendocrina Instituto de Biología y Medicina Experimental CONICET Buenos Aires Argentina departamento de Bioquímica Humana Facultad de Medicina Universidad de Buenos Aires Buenos Aires Argentina

A new role has emerged for progesterone after discovering its potent actions away from reproduction in both the central and the peripheral nervous system. The aim of the present report is to discuss progesterone’s mechanisms of action involved in myelination, remyelination and neuroinflammation. The pivotal role of the classic progesterone receptor is described and evidence is compiled about progesterone’s direct effects on oligodendrocyte linage and its indirect effects on oligodendrocyte precursor cell differentiation by decreasing the neuroinflammatory environment.

关键词： progesterone progesterone receptor oligodendrocyte differentiation myelination remyelination neuroinflammation

Daily expression of sodium-dependent glucose cotransporter-1protein in jejunum during rat ontogeny

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2019年第3期5卷 290-296页

作者： Juan I.Baston Fabricio D.Cid Enrique Caviedes-Vidal Juan G.Chediack laboratorio de Fisiopatología Endometrial Instituto de Biología y Medicina Experimental(IByME)CONICETCiudad Autoonoma de Buenos AiresC1428ADNArgentina laboratorio de biología Integrativa“Prof.E.Caviedes Codelia” Facultad de QuímicaBioquímica y FarmaciaUniversidad Nacional de San LuisSan LuisD5700HHWArgentina Instituto Multidisciplinario de Investigaciones en biología-San Luis(IMIBIO-SL CCT-SL)CONICETSan Luis D5700HHWArgentina

It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates,lipids and proteins,and the subsequent absorption of the hydrolyzed *** evolutionary matched to dietary loads and feeding *** this study,we demonstrate that the protein expression of apically located sodium-dependent glucose cotransporter-1(SGLT-1)throughout rat ontogeny is daily adjusted to afford glucose uptake when the load of this metabolically essential monosaccharide in the intestinal lumen is *** jejunal expression of SGLT-1 protein in 14 one-day-old suckling pups was found to increase at dark and early light phase(Pdeveloped circadian rhythm for SGLT-1 protein(Pdevelopmental stage and may contribute to understand the biological significance of a well-established molecular capacity to deal with the crucial increase of glucose load in the diet during the weaning process.

关键词： Intestinal SGLT-1 Protein expression Daily rhythms Ontogeny Rat

Reproductive biology of a Blue-tail Skinks(Plestiodon)Population from a Temperate Forest,East-central Puebla,México

在线全文

学校读者我要写书评

暂无评论

Asian Herpetological Research 2024年第3期15卷 183-193页

作者： Manuel FERIA-ORTIZ Isaías hazarmabeth SALGADO-UGARTE Museo de Zoología Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoIztapalapaMéxico laboratorio de Biometría y biología Pesquera Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoIztapalapaMéxico

We studied the cycles of reproduction and fat bodies of a blue-tailed skink population of an undescribed species of the Plestiodon brevirostris *** maturity is attained by females and males as they both reach about 59 mm of *** started in June-July,with ovulation occurring during late-October to mid-November,and parturition in *** size varied from two to six,with a mean of 3.86±0.15 embryos in uterus,and showed a positive correlation with female body mass and *** gestation,a significant increase in the average wet mass of embryos in uterus was *** comparison,there were no notable changes in the average dry *** growth data suggest that sexual maturity,both males and females,is reached at 16-17 months of *** and epididymides exhibited maximal weight during *** regression occurred in *** apparently takes place from mid-summer to early *** stored in female fat bodies are used for vitellogenesis and for nutrition during the winter *** males,the stored lipids appear to be used in reproductive activities during the mating season.

关键词： growth litter size minimum size at maturity reproduction Scincidae viviparity

Sex-dependent resilience to extreme drought events: implications for climate change adaptation of a South American endangered tree species

在线全文

学校读者我要写书评

暂无评论

Ecological Processes 2024年第2期13卷 48-60页

作者： Sergio Piraino Martín Ariel Hadad Yanina Antonia Ribas-Fernández Fidel Alejandro Roig laboratorio de dendrocronología e Historia Ambiental (IANIGLA CONICET ) Facultad de Ciencias Agrarias Universidad Nacional de Cuyo laboratorio de dendrocronología de Zonas áridas (CIGEOBIO CONICET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Centro de Observación de la Tierra Facultad de Ciencias Universidad Mayor

Background Recent changes in climatic trends are resulting in an increased frequency and intensity of extreme events, with unknown effect on ecosystem dynamics in the near future. Extreme drought episodes are recognized as disturbance factors capable of modifying forest dynamics and tree growth. Within this context, dioecious tree species may be impacted by climatic extremes, affecting male/female proportions and, consequently, reproductive processes and species persistence. Therefore, there is an urgent need for species-specific assessments of growth tolerance to extreme dry spells in dioecious tree species, to establish effective conservation strategies for these particular natural resources. Araucaria araucana(araucaria), an endangered dioecious Patagonian tree species, has recently undergone decay and mortality episodes in response to increasing dry climatic conditions. While sex-dependent tolerance to extreme drought episodes has been assessed in the species' humid distribution range, there is still a lack of information on the gender-based resilience of trees growing in the drier environments of the species' *** We reconstructed, through dendrochronological methods, the sex-dependent response of 105 araucaria individuals(55 female and 50 male trees) to five regional extreme dry spells employing a set of different indices. Resistance, recovery period, and average growth reduction of standardized tree-ring growth were examined, analysing the effect of biotic(sex, pre-drought stem tree growth) and abiotic(local climatic conditions before, during, and after extreme climatic episodes) factors on tree *** Sex influences only the species resistance to climatic disturbance, with male individuals showing lower tolerance to extreme drought events. Pre-drought radial growth rates and local meteorological conditions preceding, during, and following extreme dry spells strongly modulated araucaria radial growth resilience regardless of tree s

关键词： Araucaria Climate change dendrochronology Extreme drought event Resilience