检索结果-南通市图书馆

Lower and upper motor neuron involvement and their impact on disease prognosis in amyotrophic lateral sclerosis

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 2022年第1期17卷 65-73页

作者： Maria n.Zakharova anna A. Abramova Research Center of neurology MoscowRussia

Amyotrophic lateral sclerosis is a fatal neurodegenerative disease characterized by progressive muscle wasting,breathing and swallowing difficulties resulting in patient’s death in two to five years after disease *** amyotrophic lateral sclerosis,both upper and lower motor neurons of the corticospinal tracts are involved in the process of neurodegeneration,accounting for great clinical heterogeneity of the *** phenotype has great impact on the pattern and rate of amyotrophic lateral sclerosis progression and overall survival *** more homogenous patient groups in order to study the effects of drug agents on specific manifestations of the disease is a challenging issue in amyotrophic lateral sclerosis clinical *** amyotrophic lateral sclerosis has low incidence rates,conduction of multicenter trials requires certain standardized approaches to disease diagnosis and *** review focuses on the current approaches in amyotrophic lateral sclerosis classification and staging system based on clinical examination and additional instrumental methods,highlighting the role of upper and lower motor neuron involvement in different phenotypes of the *** demonstrate that both clinical and instrumental findings can be useful in evaluating severity of upper motor neuron and lower motor neuron involvement and predicting the following course of the *** disease heterogeneity in amyotrophic lateral sclerosis clinical trials could lead to study designs that will assess drug efficacy in specific patient groups,based on the disease pathophysiology and spatiotemporal *** clinical evaluation can be a sufficient screening method for dividing amyotrophic lateral sclerosis patients into clinical subgroups,we provide proof that instrumental studies could provide valuable insights in the disease pathology.

关键词： amyotrophic lateral sclerosis biomarkers of progression classification diagnostic biomarkers disease heterogeneity electrodiagnostic medicine electromyography motor neuron disease neuroimaging

Quality incentive based congestion control for multimedia communication over IP networks

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 7-12页

作者： JOHAnSEn Stian KIM anna n. PERKIS Andrew Centre for Quantifiable Quality of Service in Communication Systems norwegian University of Science and Technology Trondheim N-7034Norway

In this paper we introduce a framework for using quality as an incentive to promote proper application level congestion control. Through integrating a joint-source channel coder and feedback-based congestion control scheme, we are able to construct accurate and efficient quality incentives. The framework is applicable in all network architectures where end-to-end congestion control may be used, and is as such not specific to either best-effort or traffic class-based architectures. The concept is presented along with preliminary simulations that highlight the resulting rate control accuracy. We also discuss how to implement some well-known congestion control schemes within our framework.

关键词： Congestion control, Incentives, Video communication, Joint source/channel coding, Unequal error protection

Primary hepatic solitary fibrous tumor with histologically benign and malignant areas

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2015年第6期14卷 665-668页

作者： anna Silvanto nariman D Karanjia Izhar n Bagwan Departments of Histopathology Royal Surrey County Hospital General Sugery Royal Surrey County Hospital

Extrapleural solitary fibrous tumor （SFT） is an uncommon mesenchymal neoplasm, presenting most commonly in the intrathoracic sites but which has been reported at nu- merous extrathoracic locations. The majority of intra-thoracic SFTs are benign, but 10%-15% behave aggressively. We report a case of primary hepatic SFT with histologically benign and ma- lignant areas. A 65-year-old man underwent an abdominal CT scan following a cerebrovascular accident, which demonstrated a sharply demarcated large liver mass with a heterogenous enhancing area and occupying most of the left lobe of the liver. Histological examination following a hemihepatectomy showed an SFT with morphological patterns ranging from benign to malignant areas, including pleomorphism, increased cellularity, herringbone pattern, necrosis and a raised mitotic count. On review of the literature, only an occasional case report with malignant areas in a hepatic SFT was identified. This case highlights that SFT should be included in the differential diagnosis of a hepatic spindle cell lesion, and that on rare occasions, malignant areas can occur in this already uncommon neoplasm.

关键词： liver tumors malignant (non-HCC) liver surgery pathological changes

novel methylation specific real-time PCR test for the diagnosis of Klinefelter syndrome

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2014年第5期16卷 684-688,I0006页

作者： Akanksha Mehta anna Mielnik Peter n Schlegel Darius A Paduch Department of Urology Weill Cornell Medical College New York NY USA Department of Urology Emory University School of Medicine Atlanta GA USA

The aim of this study was to design a molecular assay for the diagnosis of Klinefelter syndrome （KS）, based on the detection of supernumerary X-chromosomes （X-chs）. DnA was extracted from peripheral blood samples of twenty-six 47,XXY males; two 46,XY/47,XXY males; twenty-two 46,XY males; and 15 females; and deaminated. Methylation-specific quantitative polymerase chain reaction （MS-qPCR） was performed using primers for unmethylated and methylated copies of the X-ch inactive-specific transcript （XIST-U and XIST-M） gene. X-ch disomy was determined on the basis of XIST methylation status. Degree of mosaicism in the 46,XY/47,XXY males was compared with karyotype and fluorescent in situ hybridization （FISH） results. Data analysis was performed using the Roche LightCycler software V. 3.5.3, including determination of crossing points （CPs） by fit-point analysis and melting curve analysis. Xoch disomy was detected in all female controls and KS patients; male controls expressed XIST-M only. CPs ranged from 29.5 to 32.5 （standard deviation （s.d.） 0.8） for XIST-U and from 29 to 31 （s.d. 0.6） for XIST-M. Limit of detection of mosaicism was 1%. Based on XlST-U/XIST-M ratios for the two 47,XXY/46,XY patients, the calculated degree of mosaicism （1.8% and 17.8%） was comparable to FISH results （2.3% and 15%, respectively）. Turnaround time from DnA deamination to final data analysis was under 9 h. We conclude that MS-qPCR is a sensitive, specific and rapid test for the detection of X-ch disomy, with applicability for the screening and diagnosis of KS, even in the setting of low grade 47,XXY/46,XY mosaicism.

关键词： DnA methylation Klinefelter syndrome mosaicism polymerase chain reaction

Comparison of Perovskite Systems Based on AFeO_(3)(A=Ce,La,Y)in CO_(2) Hydrogenation to CO

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： anna n.Matveyeva Shamil O.Omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

CO_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of CO_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeO_(3)(where A=Ce,La,Y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of nH 4 nO_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,n 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and CO_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand nH_(4) nO_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-O systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-O produced by solgel combustion(SGC).CO_(2) conversion into CO at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)nces in properties between La-Fe-O obtained by the SCS and SGC methods can be attributed to diff erent ratios of oxygen and lanthanum vacancy contributions,hydroxyl coverage,morphology,and free iron oxide *** situ FTIR data revealed that CO_(2) hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La-Fe-O,obtained by the SCS method.γ-Al_(2)O_(3) improves the dispersion of CeFeO_(3) and LaFeO_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeO_(3) CeFeO_(3) YFeO_(3) Solution combustion synthesis CO_(2) hydrogenation Reverse water–gas reaction(rWGS)

Role of ultrasound in colorectal diseases

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2016年第43期22卷 9477-9487页

作者： Renáta Bor anna Fábián Zoltán Szepes First Department of Medicine University of Szeged

Ultrasound is an undervalued non-invasive examination in the diagnosis of colonic diseases. It has been replaced by the considerably more expensive magnetic resonance imaging and computed tomography, despite the fact that, as first examination, it can usefully supplement the diagnostic process. Transabdominal ultrasound can provide quick information about bowel status and help in the choice of adequate further examinations and treatment. Ultrasonography,as a screening imaging modality in asymptomatic patients can identify several colonic diseases such as diverticulosis, inflammatory bowel disease or cancer. In addition, it is widely available, cheap, non-invasive technique without the use of ionizing radiation, therefore it is safe to use in childhood or during pregnancy, and can be repeated at any time. new ultrasound techniques such as elastography, contrast enhanced and Doppler ultrasound, miniprobes rectal and transperineal ultrasonography have broadened the indication. It gives an overview of the methodology of various ultrasound examinations, presents the morphology of normal bowel wall and the typical changes in different colonic diseases. We will pay particular attention to rectal and transperineal ultrasound because of their outstanding significance in the diagnosis of rectal and perineal disorders. This article seeks to overview the diagnostic impact and correct indications of bowel ultrasound.

关键词： Ultrasound Perineal ultrasound Rectal endosonography Gastrointestinal diseases

Long-term effects of environmentally relevant concentrations of silver nanoparticles on microbial biomass, enzyme activity,and functional genes involved in the nitrogen cycle of loamy soil

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 Environmental Sciences 2018年第7期30卷 12-22页

作者： anna-Lena Grün Susanne Straskraba Stefanie Schulz Michael Schloter Christoph Emmerling Faculty of Regional and Environmental Sciences Department of Soil Science University of Trier J.W.Goethe University Institute of Molecular Biosciences Research for Comparative Microbiome Analysis Helmholtz Zentrum München Chair for Soil Science Technische Universit?t München

The increasing production and use of engineered silver nanoparticles（AgnP） in industry and private households are leading to increased concentrations of AgnP in the environment. An ecological risk assessment of AgnP is needed, but it requires understanding the long term effects of environmentally relevant concentrations of AgnP on the soil microbiome. Hence, the aim of this study was to reveal the long-term effects of AgnP on soil microorganisms. The study was conducted as a laboratory incubation experiment over a period of one year using a loamy soil and AgnP concentrations ranging from 0.01 to 1 mg AgnP/kg soil. The short term effects of AgnP were, in general, ***, after one year of exposure to 0.01 mg AgnP/kg, there were significant negative effects on soil microbial biomass（quantified by extractable DnA; p = 0.000） and bacterial ammonia oxidizers（quantified by amo A gene copy numbers; p = 0.009）. Furthermore, the tested AgnP concentrations significantly decreased the soil microbial biomass, the leucine aminopeptidase activity（quantified by substrate turnover; p = 0.014）, and the abundance of nitrogen fixing microorganisms（quantified by nif H gene copy numbers; p = 0.001）. The results of the positive control with Ag nO3 revealed predominantly stronger effects due to Ag＋ion release. Thus, the increasing toxicity of AgnP during the test period may reflect the long-term release of Ag^＋ions. nevertheless, even very low concentrations of AgnP caused disadvantages for the microbial soil community, especially for nitrogen cycling, and our results confirmed the risks of releasing AgnP into the environment.

关键词： Silver nanoparticles Soil Microbiome amoA nifH Leucine aminopeptidase activity AgPure

Deletion or underexpression of the Y-chromosome genes CDY2 and HSFY is associated with maturation arrest in American men with nonobstructive azoospermia

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2012年第5期14卷 676-682页

作者： Peter J Stahl anna n Mielnik Christopher E Barbieri Peter n Schlegel Darius A Paduch Department of Urology Weill Cornell Medical CollegeNew York Presbyterian HospitaI-CornellNew YorkNY 10065USA

Maturation arrest （MA） refers to failure of germ cell development leading to clinical nonobstructive azoospermia. Although the azoospermic factor （AZF） region of the human Y chromosome is clearly implicated in some cases, thus far very little is known about which individual Y-chromosome genes are important for complete male germ cell development. We sought to identify single genes on the Y chromosome that may be implicated in the pathogenesis of nonobstructive azoospermia associated with MA in the American population. Genotype-phenotype analysis of 132 men with Y-chromosome microdeletions was performed. Protein-coding genes associated with MA were identified by visual analysis of a genotype-phenotype map. Genes associated with MA were selected as those genes within a segment of the Y chromosome that, when completely or partially deleted, were always associated with MA and absence of retrievable testicular sperm. Expression of each identified gene transcript was then measured with quantitative RT-PCR in testicular tissue from separate cohorts of patients with idiopathic MA and obstructive azoospermia. Ten candidate genes for association with MA were identified within an 8.4-Mb segment of the Y chromosome overlapping the AZFb region. CDY2and HSFYwere the only identified genes for which differences in expression were observed between the MA and obstructive azoospermia cohorts. Men with obstructive azoospermia had 12-fold higher relative expression of CDY2transcript （1.33__.0.40 vs. 0.11＋_0.04; P=O.O003） and 16-fold higher expression of HSFYtranscript （0.78__.0.32 vs. 0.05_0.02; P=O.O005） compared to men with MA. CDY2 and HSFYwere also underexpressed in patients with Sertoli cell only syndrome. These data indicate that CDY2and HSFYare located within a segment of the Y chromosome that is important for sperm maturation, and are underexpressed in testicular tissue derived from men with MA. These observations suggest that impairments in CDY2 or HSFYexpression could be impli

关键词： CDY1 protein CDY2 protein genetics histology HSFY human make infertility nonobstructive azoospermia spermato-genesis sperm maturation

Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Avian Research 2024年第1期15卷 91-97页

作者： nora Agh Henriett anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(ng did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences