检索结果-南通市图书馆

Grasslands Response to Livestock Grazing Intensity in the Austral Pampas (Argentina): Testing the Intermediate Disturbance Hypothesis

在线全文

学校读者我要写书评

暂无评论

PHYTON-INTERNATIONAL JOURNAL OF EXPERIMENTAL BOTANY 2024年第8期93卷 2037-2050页

作者： de Villalobos, Ana elena Long, maria Andrea Consejo Nacl Invest Cient & Tecn CERZOS Grp Invest Ecosistemas Pastizal RA-8000 Bahia Blanca Buenos Aires Argentina Univ Nacl Sur Dept Biol Bioquim & Farm RA-8000 Bahia Blanca Buenos Aires Argentina

Livestock grazing has a significant impact on natural grasslands, with approximately one-third of the world's land area dedicated to this industry. Around 20% of global grasslands are highly degraded due to overgrazing, affecting their productivity and conservation capacity. Best practices are required to ensure sustainable livestock production that supports biodiversity. The Intermediate Disturbance Hypothesis (IDH) suggests that environments with moderate levels of disturbance exhibit a higher species diversity. Moderate grazing can reduce the dominance of certain species, thereby enhancing plant diversity. However, concerns arise regarding the increase of exotic and unpalatable species under moderate grazing levels, complicating grassland conservation efforts. The impact of livestock grazing on the functional structure of grasslands depends on factors such as grazing intensity, livestock species, and environmental conditions. Variations in grazing intensity may increase specific and functional diversity under moderate grazing, potentially masking the presence of invasive exotic species. In the Austral Pampas (Pampean phytogeographic province, Buenos Aires, Argentina), grasslands face various pressures from domestic livestock grazing that endanger their integrity if not properly managed. Therefore, our study aims to investigate potential differences in species richness and diversity, functional diversity, exotic plant abundance, and the number and distribution of plant functional groups across varying grazing intensities. The IDH is utilized as a tool to regulate livestock pressure for grassland conservation. Species and functional diversity indices were used to assess the impact of grazing on grassland diversity. Moderate grazing increased species and functional diversity, while intensively grazed or ungrazed areas showed reduced diversity. Livestock presence influenced the balance between native and exotic plants, with ungrazed areas having higher native plant a

关键词： Natural grasslands grazing effects disturbance speci fi c and functional diversity FERAL HORSES DIVERSITY INVASION VEGETATION PLANTS FIRE RAIN

Outpatient management of obscure gastrointestinal bleeding:A new perspective in high-risk patients

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第19期30卷 2502-2504页

作者： maria elena Riccioni Clelia Marmo Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy CEMAD Centro Malattie dell’Apparato Digerente Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy

Mid-gastrointestinal bleeding accounts for approximately 5%-10%of all gastrointestinal bleeding cases,and vascular lesions represent the most frequent *** rebleeding rate for these lesions is quite high(about 42%).We hereby recommend that scheduled outpatient management of these patients could reduce the risk of rebleeding episodes.

关键词： Gastrointestinal bleeding Small bowel bleeding Recurrent bleeding Rebleeding risk Rebleeding Outpatient management

Plasticity of photorespiratory carbon concentration mechanism in Sedobassia sedoides(Pall.)Freitag&*** under elevated CO_(2)concentration and salinity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Arid Land 2024年第7期16卷 963-982页

作者： Zulfira RAKHMANKULOVA elena SHUYSKAYA maria PROKOFIEVA Kristina TOdeRICH Pavel VORONIN Timiryazev Institute of Plant Physiology Russian Academy of SciencesMoscow 127276Russia Graduate School of Bioresources Mie University1577 KurimamachiyaTsu 514-8507Japan

Rising atmospheric CO_(2)(carbon dioxide)concentrations and salinization are manifestations of climate change that affect plant growth and *** with an intermediate C_(3)-C_(4)type of photosynthesis live in a wide range of precipitation,temperature,and soil quality,but are more often found in warm and dry *** of the intermediate C_(3)-C_(4)photosynthetic type is C_(2)photosynthesis with a carbon concentration mechanism(CCM)that reassimilates CO_(2)released via ***,the ecological significance under which C_(2)photosynthesis has advantages over C_(3)and C_(4)plants remains largely *** tolerance and functioning of CCM were studied in plants from two populations(P1 and P2)of Sedobassia sedoides(Pall.)Freitag&*** *** with C_(2)photosynthesis exposed to 4 d and 10 d salinity(200 mM NaCl)at ambient(785.7 mg/m^(3),aCO_(2)and elevated(1571.4 mg/m^(3),eCO_(2))CO_(2).On the fourth day of salinity,an increase in Na+content,activity catalase,and superoxide dismutase was observed in both populations.P2 plants showed an increase in proline content and a decrease in photosynthetic enzyme content:rubisco,phosphoenolpyruvate carboxylase(PEPC),and glycine decarboxylase(GDC),which indicated a weakening of C_(2)and C_(4)characteristics under *** under 10 d salinity led to an increased Na^(+)content and activity of cyclic electron flow around photosystem I(PSI CEF),a decreased content of K^(+)and GDC in both populations.P1 plants showed greater salt tolerance,which was assessed by the degree of reduction in photosynthetic enzyme content,PSI CEF activity,and changes in relative growth rate(RGR).Differences between populations were evident under the combination of eCO_(2)and *** long-term salinity and eCO_(2),more salt-tolerant P1 plants had a higher dry biomass(DW),which was positively correlated with PSI CEF *** less salt-tolerant P2 plants,DW correlated with transpiration and dark

关键词： photosystemsⅠandⅡ carbon-concentrating mechanism glycine decarboxylase rubisco phosphoenolpyruvate carboxylase(PEPC) cyclic electron flow salinity stress drylands

Arlenea delicata *** ***.,a new ephedroid plant from the Early Cretaceous Crato Formation,Araripe Basin,Northeast Brazil

在线全文

学校读者我要写书评

暂无评论

Plant Diversity 2024年第3期46卷 362-371页

作者： Alita maria Neves Ribeiro Yong Yang Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de lima Programa de Pos-Graduaçao em Diversidade Biologica e Recursos Naturais Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the Environment159 Longpan RoadNanjing Forestry UniversityNanjing210037China Laboratorio de Paleontologia Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Laboratorio de Estudos da Flora Regional Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Gondwanan Plants Lab Universidade Federal de PernambucoCentro Academico de VitoriaRua Do Alto Reservatorio S/nBela Vista55608-680Vitoria de Santo AntaoPernambucoBrazil Programa de Pos-Graduaçao em Geociencias(PPGEOC) Universidade Federal de Pernambuco(UFPE)Rua Av.da ArquiteturaS/n°CEP-50740-550Cidade UniversitariaRecifePernambucoBrazil

Ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of NE ***,few ephedroid macrofossils have been reported from South ***,we describe a new plant of the family Ephedraceae,Arlenea delicata *** ***.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive *** has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen *** new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed *** new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the Early ***,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(Enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of Ephedraceae in the Lower Cretaceous.

关键词： Early Cretaceous Gnetophytes Arlenea delicata Ephedrales Crato Formation

Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第6期30卷 579-598页

作者： Fabian Fellipe Bueno Lemos Caroline Tianeze de Castro Marcel Silva Luz Gabriel Reis Rocha Gabriel lima Correa Santos Luís Guilherme de Oliveira Silva mariana Santos Calmon Cláudio lima Souza Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira Dulciene maria de Magalhães Queiroz Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil Instituto de Saúde Coletiva Universidade Federal da BahiaSalvador 40110040BahiaBrazil Campus Toledo Universidade Federal do ParanáToledo 85919-899ParanáBrazil Laboratory of Research in Bacteriology UFMGBelo Horizonte 30130-100Minas GeraisBrazil

BACKGROUND Helicobacter pylori(***)infection has been well-established as a significant risk factor for several gastrointestinal *** urea breath test(UBT)has emerged as a leading non-invasive method for detecting *** numerous studies confirming its substantial accuracy,the reliability of UBT results is often compromised by inherent *** findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of *** *** To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for *** infection in adult patients with *** We conducted an independent search of the PubMed/MEDLINE,EMBASE,and Cochrane Central databases until April *** search included diagnostic accuracy studies that evaluated at least one of the index tests(^(13)C-UBT or ^(14)C-UBT)against a reference *** used the QUADAS-2 tool to assess the methodo-logical quality of the *** utilized the bivariate random-effects model to calculate sensitivity,specificity,positive and negative test likelihood ratios(LR+and LR-),as well as the diagnostic odds ratio(DOR),and their 95%confidence *** conducted subgroup analyses based on urea dosing,time after urea administration,and assessment *** investigate a possible threshold effect,we conducted Spearman correlation analysis,and we generated summary receiver operating characteristic(SROC)curves to assess ***,we visually inspected a funnel plot and used Egger’s test to evaluate publication *** both as reliable diagnostic tools in clinical *** In summary,our study has demonstrated that ^(13)C-UBT has been found to outperform the ^(14)C-UBT,making it the preferred diagnostic ***,our results emphasize the significance of carefully considering urea dosage,assessment timing,and measurement techniques for both tests to enh

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy Meta-analysis

Shear-wave elastography to predict hepatocellular carcinoma after hepatitis C virus eradication:A systematic review and meta-analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2024年第10期30卷 1450-1460页

作者： Giorgio Esposto Paolo Santini Linda Galasso Irene Mignini maria elena Ainora Antonio Gasbarrini maria Assunta Zocco CEMAD Digestive Disease Center Fondazione Policlinico Universitario“A.Gemelli”IRCCSCatholic University of RomeRome 00168Italy Fondazione Policlinico Universitario Agostino Gemelli IRCCS Fondazione Policlinico Universitario Agostino Gemelli IRCCS-UniversitàCattolica del Sacro CuoreRome 00168Italy Medicina Interna e Gastroenterologia CEMAD Digestive Disease CenterUniversitàCattolica del Sacro CuoreFondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy

BACKGROUND Direct-acting antiviral agents(DAAs)are highly effective treatment for chronic hepatitis C(CHC)with a significant rate of sustained virologic response(SVR).The achievement of SVR is crucial to prevent additional liver damage and slow down fibrosis *** assessment of fibrosis degree can be performed with transient elastography,magnetic resonance elastography or shear-wave elastography(SWE).Liver elastography could function as a predictor for hepato-cellular carcinoma(HCC)in CHC patients treated with *** To explore the predictive value of SWE for HCC development after complete clearance of hepatitis C virus(HCV).METHODS A comprehensive literature search of clinical studies was performed to identify the ability of SWE to predict HCC occurrence after HCV *** accordance with the study protocol,a qualitative and quantitative analysis of the evidence was *** At baseline and after 12 wk of follow-up,a trend was shown towards greater liver stiffness(LS)in those who go on to develop HCC compared to those who do not[baseline LS standardized mean difference(SMD):1.15,95%confidence interval(95%CI):020-2.50;LS SMD after 12 wk:0.83,95%CI:0.33-1.98].The absence of a statistically significant difference between the mean LS in those who developed HCC or not may be related to the inability to correct for confounding factors and the absence of raw source *** was a statist-ically significant LS SMD at 24 wk of follow-up between patients who developed HCC vs not(0.64;95%CI:0.04-1.24).CONCLUSION SWE could be a promising tool for prediction of HCC occurrence in patients treated with *** studies with larger cohorts and standardized timing of elastographic evaluation are needed to confirm these data.

关键词： Shear-wave elastography Hepatocellular carcinoma Hepatitis C virus Sustained virologic response

Surgical management of tegmen defects of the temporal bone and meningoencephalic herniation: our experience

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Otology 2024年第1期19卷 30-34页

作者： Giuseppe de Donato Emanuela Fuccillo Alberto maria Saibene elena Ferrari Giorgia Carlotta Pipolo Antonia Pisani Liliana Colletti Anastasia Urbanelli Luigi de Donato Giovanni Felisati Otorhinolaryngology Unit Head and Neck DepartmentASST Santi Paolo e Carlo HospitalVia Antonio di Rudinì820142MilanItaly department of Health Sciences University of MilanVia Festa del Perdono720122MilanItaly department of Biomedical Surgical and Dental SciencesUniversity of MilanVia Festa del Perdono720122MilanItaly ENT Unit Department of Surgical SciencesUniversity of TurinVia Verdi810124TurinItaly

1. Introduction The tegmental wall of the tympanic cavity is a thin plate of the temporal bone that separates the middle cranial fossa(MCF) from the ear. This anatomical region consists of two areas: an anterior one, comprised of the tegmen tympani(To′th et al., 2007), and a posterior one, formed by the tegmen antri and the tegmen mastoideum(Makki et al., 2011). In some patients, the tegmental region of the temporal bone can be interrupted, causing a tegmen defect(TD). A TD is sometimes associated with a meningoencephalic herniation(MEH), in which brain tissue herniates through a TD.

关键词： al. herniation bone

Dynamic contrast enhanced ultrasound in differential diagnosis of hepatocellular carcinoma: A systematic review and meta-analysis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第6期16卷 2804-2815页

作者： Giorgio Esposto Paolo Santini Fabrizio Termite Linda Galasso Irene Mignini maria elena Ainora Antonio Gasbarrini maria Assunta Zocco department of CEMAD Digestive Disease Center Fondazione Policlinico Universitario A Gemelli IRCCSCatholic University of RomeRome 00168Italy department of Fondazione Policlinico Universitario Agostino Gemelli IRCCS UniversitàCattolica del Sacro CuoreRome 00168Italy department of Medicina Interna e Gastroenterologia CEMAD Digestive Disease CenterFondazione Policlinico Universitario A Gemelli IRCCSUniversitàCattolica del Sacro CuoreRome 00168Italy

BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(*** or metastasis)is highly challenging and definitive diagnosis still relies on histological *** patterns of enhancement and wash-out of liver nodules can be used to stratify the risk of malignancy only in cirrhotic patients and HCC frequently shows atypical *** contrast-enhanced ultrasound(DCEUS)with standardized software could help to overcome these obstacles,providing functional and quantitative parameters and potentially improving accuracy in the evaluation of tumor *** To explore clinical evidence regarding the application of DCEUS in the differential diagnosis of liver *** A comprehensive literature search of clinical studies was performed to identify the parameters of DCEUS that could relate to histological *** accordance with the study protocol,a qualitative and quantitative analysis of the evidence was *** Rise time was significantly higher in HCC patients with a standardized mean difference(SMD)of 0.83(95%CI:0.48-1.18).Similarly,other statistically significant parameters were mean transit time local with a SMD of 0.73(95%CI:0.20-1.27),peak enhancement with a SMD of 0.37(95%CI:0.03-0.70),area wash-in area under the curve with a SMD of 0.47(95%CI:0.13-0.81),wash-out area under the curve with a SMD of 0.55(95%CI:0.21-0.89)and wash-in and wash-out area under the curve with SMD of 0.51(95%CI:0.17-0.85).SMD resulted not significant in fall time and wash-in rate,but the latter presented a trend towards greater values in HCC compared to intrahepatic *** DCEUS could improve non-invasive diagnosis of HCC,leading to less liver biopsy and early *** quantitative analysis needs to be applied on larger cohorts to confirm these preliminary results.

关键词： Dynamic contrast enhanced ultrasound Hepatocellular carcinoma Intracellular cholangiocarcinoma Quantitative ultrasound Liver cancer Time-intensity curve

Calcium-sensitive protein MLC1 as a possible modulator of the astrocyte functional state

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第7期20卷 2008-2010页

作者： elena Ambrosini Angela Lanciotti maria Stefania Brignone department of Neuroscience Istituto Superiore di SanitàRomeItaly

Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental stage to adult *** maintain the optimal functionality of the brain,astroglial cells are particularly committed to reacting to every change in tissue homeostatic conditions,from mild modifications of the physiological environment,a process called astrocyte activation,to the more severe alterations occurring in pathological situations causing astrocyte reactivity or reactive astrogliosis(Escartin et al.,2021).During these reactive states,astrocytes mount an active,progressive response encompassing morphological,molecular,and interactional remodeling,leading to the acquisition of new functions and the loss of others,whose intensity,duration,and reversibility are dependent on the nature of the stimulus and regulated in a context-specific manner.

关键词： alterations modulator maintain