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81.
82.
Irena Trbojević-Akmačić Frano Vučković Marija Vilaj Andrea Skelin Lennart C. Karssen Jasminka Krištić Julija Jurić Ana Momčilović Jelena Šimunović Massimo Mangino Manuela De Gregori Maurizio Marchesini Concetta Dagostino Jerko Štambuk Mislav Novokmet Richard Rauck Yurii S. Aulchenko Dragan Primorac Gordan Lauc 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(10):2124-2133
Background
Low back pain (LBP) is the symptom of a group of syndromes with heterogeneous underlying mechanisms and molecular pathologies, making treatment selection and patient prognosis very challenging. Moreover, symptoms and prognosis of LBP are influenced by age, gender, occupation, habits, and psychological factors. LBP may be characterized by an underlying inflammatory process. Previous studies indicated a connection between inflammatory response and total plasma N-glycosylation. We wanted to identify potential changes in total plasma N-glycosylation pattern connected with chronic low back pain (CLBP), which could give an insight into the pathogenic mechanisms of the disease.Methods
Plasma samples of 1128 CLBP patients and 760 healthy controls were collected in clinical centers in Italy, Belgium and Croatia and used for N-glycosylation profiling by hydrophilic interaction ultra-performance liquid chromatography (HILIC-UPLC) after N-glycans release, fluorescent labeling and clean-up. Observed N-glycosylation profiles have been compared with a cohort of 126 patients with acute inflammation that underwent abdominal surgery.Results
We have found a statistically significant increase in the relative amount of high-branched (tri-antennary and tetra-antennary) N-glycan structures on CLBP patients' plasma glycoproteins compared to healthy controls. Furthermore, relative amounts of disialylated and trisialylated glycan structures were increased, while high-mannose and glycans containing bisecting N-acetylglucosamine decreased in CLBP.Conclusions
Observed changes in CLBP on the plasma N-glycome level are consistent with N-glycosylation changes usually seen in chronic inflammation.General significance
To our knowledge, this is a first large clinical study on CLBP patients and plasma N-glycome providing a new glycomics perspective on potential disease pathology. 相似文献83.
Joseph M. Craine Peter B. Reich G. David Tilman David Ellsworth Joseph Fargione Johannes Knops Shahid Naeem 《Ecology letters》2003,6(7):623-625
In an experiment that factorially manipulated plant diversity, CO2, and N, we quantified the effects of the presence of species on assemblage biomass over 10 time points distributed over 5 years. Thirteen of the 16 species planted had statistically significant effects on aboveground and/or belowground biomass. Species differed dramatically in their effects on biomass without any relationship between aboveground and below‐ground effects. Temporal complementarity among species in their effects seasonally, successionally, and in response to a dry summer maintained the diversity–biomass relationships over time and may be the cause behind higher diversity plots having less variation in biomass over time. The response of plant biomass to elevated N, but not CO2, was at times entirely dependent on the presence of a single species. 相似文献
84.
武陵源风景区生态承载力预警 总被引:3,自引:1,他引:3
随着人类面临的严重环境挑战,可持续发展模式作为全人类共同的选择变得越来越重要。生态承载力作为可持续发展的衡量指标,通过生态承载力水平与生态荷载状况表现出来。可持续承载力预警是以可持续发展为目标进行生态承载力调控。利用主成分分析法、层次分析法构建了武陵源风景区的生态承载力评价指标体系,作为模型的输入层预警指标,并利用状态空间法求算的生态承载指数进行警度区间的划分,通过样本训练、建立BP神经网络模型,进行生态承载预警。从风景区的资源承载、环境承载、生态弹性和生态承压等方面来考虑,析出17个资源类、环境类、社会经济类指标作为评价指标体系。对于武陵源风景区的承载状态,从时间上看,2000年曾出现超载状态,主要是风景区的核心区范围内出现城市化现象所致;从空间上看,协和乡出现超载状态,其主要原因在于资源的开发利用上。基于BP网络模型实现的生态承载力预警,用于预测预报未来的可持续发展的发展状态,可以及时反映可持续状态的调控效果,为区域系统的可持续发展提供科学依据。 相似文献
85.
Habitat and landscape factors associated with neotropical waterbird occurrence and richness in wetland fragments 总被引:3,自引:0,他引:3
Habitat destruction alters the structure and spatial arrangement of remnants and creates a novel matrix, affecting the structure
of biological communities. This study evaluated the contribution of patch, class and landscape level attributes of 42 wetland
fragments and surrounding landscapes on the richness, abundance and presence of waterbird species. Twelve monthly censuses
identified 55 species––ranging from 3 to 40 among fragments, and a total of 84,286 birds––ranging from 15 to 19,322. Wetland
areas varied from 0.2 ha to 145.2 ha. The presence of 37 out of 42 species could be predicted from the structure of the fragments
and the landscapes. The most important predictors were the wetland area (22 models), the rice field matrix permeability (13
models), the microhabitat richness (7 models), the wetland connectivity (5 models), and the wetland isolation (5 models).
Discriminant analysis showed that fragments richer in species than expected from their areas, are found in landscapes with
greater connectivity and matrix permeability than the species-poor fragments. The total area of rice fields was not related
to the richness, abundance or presence of waterbirds in the wetlands fragments. The results suggest that the maintenance of
the connectivity among fragments and the matrix permeability through rice-fields could be managed to foster the waterbird
conservation at the landscape scale. 相似文献
86.
Richard M. Torack 《Cell and tissue research》1971,113(1):1-12
Summary Following an intracisternal injection of sodium chloride, sodium has been localized in paraventricular and subpial tissues of the posterior fossa by means of the pyroantimonate histochemical technique, with the use of a buffered pyroantimonate medium. The electron dense deposit is present in these tissues within 4 minutes after injection and is found only extracellularly except in the area postrema. This finding supports the contention that sodium is chiefly an extracellular ion and that the cerebrospinal fluid and the extracellular fluid are in equilibrium at these sites. In the area postrema, an intracellular precipitate is noted in the vesicular structures of the atypical astrocytes of this structure and in pinocytic vesicles of the large blood vessels. The intraglial localization of sodium in the area postrema is discussed in relation to a possible function of this structure as a regulator of cerebrospinal fluid ionic content.This work was supported by grant number NB-08549-02 from the National Institute of Neurological Disease and Stroke, Bethesda, Maryland. 相似文献
87.
Finn A. Geneser-Jensen 《Cell and tissue research》1973,137(1):1-12
Summary 1. The distribution of monoamine oxidase (MAO) within the dentate area, a part of the hippocampal region, has been described for the adult guinea pig.2. The histochemical demonstration of the enzyme was done essentially according to the tryptamine-tetrazolium method of Glenner et al., and the staining reactivity was controlled by complete inhibition with iproniazide.3. Most of the MAO in the dentate area was present in a stratified pattern. Within the molecular layer, a supragranular third reacted heavily, while a more weakly staining superficial layer could be distinguished from an intermediate, still paler lamina. The granular cell bodies were unstained. In the hilus, five layers showing alternating stronger and weaker activity were observed. The distribution of the MAO staining was compared with conventional anatomical subdivision of the dentate region.4. The guinea pig dentate area appears to have a greater amount and more stratified distribution of MAO than the comparable region previously described in the rat.I am indebted to Mrs. E. Kjær Hansen, Mrs. L. Knudsen, Mr. A. Meier, Mr. Th. Nielsen, Mrs. K. Sørensen, and Miss M. Sørensen for skillful technical assistance. This study was supported in part by U.S.P.H.S. Grant NS 07998. 相似文献
88.
Raghavendra Mishra 《Ocean Development & International Law》2016,47(1):29-39
The judgments in maritime delimitation cases involving Bangladesh and Myanmar (2012) and between Bangladesh and India (2014) have resulted in a “Grey Area” in the northern Bay of Bengal involving intersecting and overlapping rights and responsibilities in terms of the exclusive economic zone (EEZ) and continental shelf regimes. This article seeks to identify a functional solution for this Grey Area. 相似文献
89.
A small-scale, “no-use zone policy” has been implemented since 1992 at Eilat’s Coral Nature Reserve (Northern Red Sea). Six
years later, the status of this closed-to-the-public reef area was compared to two nearby open-to-the-public sites, by evaluating
populations of the scleractinian coral Stylophora pistillata in the strolling zone (0.5–1.5 m depth). Results from the open sites show that: (1) Live coral cover was three times lower
than at the closed site; (2) numbers of small colonies (recruits) were significantly higher than in the closed site, while
numbers of medium and large size colonies (geometric mean radius, rˉ>4.1 cm) per m2 were significantly lower; (3) maximum rˉ was almost half than that in the closed site (9.6 cm versus 16.7 cm); (4) average number of broken colonies was three times
higher than in the closed site; (5) significantly fewer colonies were partially dead. The latter result may reflect senescence
processes in the large colonies of the closed site. Although colony breakage is reduced, it appears that the “no-use zone”
policy is not sufficient for protecting small reef areas. The intense exploitation of Eilat’s coral reef by the tourist industry
requires’ in addition to the conventional protective measures, the initiation of novel management solutions such as reef restoration
by sexual and asexual recruits.
Accepted: 11 August 1999 相似文献
90.
毛乌素沙地若干植物光合作用,蒸腾作用和水分利用效率种间及生境间差异 总被引:34,自引:0,他引:34
蒋高明 《Acta Botanica Sinica》1999,41(10):1114-1124
报道了内蒙古毛乌素沙地不同生境下66种不同科属植物的光合作用、蒸腾作用和水分利用效率特征。这几种生境包括流动沙丘、固定沙丘、滩地和湿地,所分布的植物与表现的生理生态特征不同。研究结果表明:藜科、禾本科、豆科等具有C4光合碳同化途径或具固氮能力的植物具有较高的光合能力,其净光合速率20~30μmolCO2·m-2·s-1;而松柏科的常绿植物具最低的光合速率,0~5μmolCO2·m-2·s-1。菊科、玄参科、禾本科等具C3途径和无固氮能力的植物蒸腾作用最高,为20~30mmolH2O·m-2·s-1;松柏科、杨柳科和菊科的个别植物蒸腾速率很低,为0~5mmolH2O·m-2·s-1。豆科、禾本科和藜科中具C4光合途径或固氮能力的一些植物(灌木或草本植物)具有较高的水分利用效率。然而,植物的这些生理生态指标随不同季节和生境表现出不同的特点,在晚夏季所测的净光合速率、蒸腾速率分别比初夏季高26%和40%,而水分利用效率下降12%。从总体趋势来看,随着生境沿着由湿到干的不同水分供应等级,如从湿地、滩地、固定沙丘至流动沙丘,光合作用和蒸腾作用呈现减弱的趋势,而水分利用效率则呈现升高的趋势 相似文献