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31.
A Luquita L Urli MJ Svetaz AM Gennaro ME Giorgetti G Pistone R Volpintesta S Palatnik M Rasia 《Journal of biomedical science》2010,17(1):8
Background
Hyaluronic acid (HA) is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs) with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA) patients, a serum HA-increasing pathology. 相似文献32.
33.
目的:采用SF-36量表中文版评价农村中老年人生存质量,并为提高农村中老年人的生存质量和健康水平提供科学依据和建议。方法:采用随机抽样的方法,采用面对面访谈的形式,记分方法参照国际生存质量评价计划(IQOLA)的制定标准,评价其生理和心理健康状况。结果:1590名农村中老年人男性生存质量得分高于女性。经济水平对农村中老年人的生理健康的影响大于对其心理健康的影响。配偶健在的农村中老年人的各维度得分均高于无配偶者。农村中老年人的各维度得分随教育水平的升高呈升高趋势。结论:农村中老年人的生存质量与年龄成负相关,同时也受文化程度和经济水平等多个因素的影响。因而,对农村中老年人这一弱势群体应该给予更多关注。 相似文献
34.
Historical isolation during Pleistocene low sea level periods is thought to have contributed to divergence among marine basin populations across the Coral Triangle. In the Philippine archipelago, populations in the South China Sea, Sulu Sea–inland seas, and Philippine Sea‐Celebes Sea basins might have been partially isolated. Meanwhile, present‐day broadscale oceanographic circulation patterns suggest connectivity between these basins. To evaluate hypotheses regarding the influence of historical and contemporary factors on genetic structure, phylogeographic patterns based on mitochondrial control region sequences for a reef‐associated fish, Siganus fuscescens, were analysed. Three distinct lineages were recovered. One lineage was identified as the morphologically similar species Siganus canaliculatus, while two lineages are monophyletic with S. fuscescens. Clade divergence and demographic expansion in S. fuscescens occurred during the Pleistocene. A strong signal of latitudinal structure was detected (ΦCT = 0.188), driven by marked differences in clade distribution: one clade is widely distributed (clade A), while a second clade (clade B) has a restricted northern distribution. Regional structure of clade A is consistent with the basin isolation hypothesis (ΦCT = 0.040) and suggests isolation of the South China Sea (ΦCT = 0.091). Fine‐scale structure was observed in the South China Sea and south Philippine Sea, while Sulu Sea and inland seas were unstructured. Genetic structure across multiple spatial scales (archipelagic, regional, and fine‐scale within basins) suggests the influence of vicariant barriers and contemporary limits to gene flow in S. fuscescens that may be influenced by oceanographic circulation, geographical distance between available habitats, and latitudinal temperature differences. 相似文献
35.
Thérèse S Lapperre Jacob K Sont Annemarie van Schadewijk Margot ME Gosman Dirkje S Postma Ingeborg M Bajema Wim Timens Thais Mauad Pieter S Hiemstra 《Respiratory research》2007,8(1):85-9
Background
Chronic Obstructive Pulmonary Disease (COPD) is associated with bronchial epithelial changes, including squamous cell metaplasia and goblet cell hyperplasia. These features are partially attributed to activation of the epidermal growth factor receptor (EGFR). Whereas smoking cessation reduces respiratory symptoms and lung function decline in COPD, inflammation persists. We determined epithelial proliferation and composition in bronchial biopsies from current and ex-smokers with COPD, and its relation to duration of smoking cessation.Methods
114 COPD patients were studied cross-sectionally: 99 males/15 females, age 62 ± 8 years, median 42 pack-years, no corticosteroids, current (n = 72) or ex-smokers (n = 42, median cessation duration 3.5 years), postbronchodilator FEV1 63 ± 9% predicted. Squamous cell metaplasia (%), goblet cell (PAS/Alcian Blue+) area (%), proliferating (Ki-67+) cell numbers (/mm basement membrane), and EGFR expression (%) were measured in intact epithelium of bronchial biopsies.Results
Ex-smokers with COPD had significantly less epithelial squamous cell metaplasia, proliferating cell numbers, and a trend towards reduced goblet cell area than current smokers with COPD (p = 0.025, p = 0.001, p = 0.081, respectively), but no significant difference in EGFR expression. Epithelial features were not different between short-term quitters (<3.5 years) and current smokers. Long-term quitters (≥3.5 years) had less goblet cell area than both current smokers and short-term quitters (medians: 7.9% vs. 14.4%, p = 0.005; 7.9% vs. 13.5%, p = 0.008; respectively), and less proliferating cell numbers than current smokers (2.8% vs. 18.6%, p < 0.001).Conclusion
Ex-smokers with COPD had less bronchial epithelial remodelling than current smokers, which was only observed after long-term smoking cessation (>3.5 years).Trial registration
NCT00158847 相似文献36.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
37.
The fate of tetanus toxin (mol wt 150,000) subsequent to its retrograde axonal transport in peripheral sympathetic neurons of the rat was studied by both electron microscope autoradiography and cytochemistry using toxin-horseradish peroxidase (HRP) coupling products, and compared to that of nerve growth factor (NGF), cholera toxin, and the lectins wheat germ agglutinin (WGA), phytohaemagglutinin (PHA), and ricin. All these macromolecules are taken up by adrenergic nerve terminals and transported retrogradely in a selective, highly efficient manner. This selective uptake and transport is a consequence of the binding of these macromolecules to specific receptive sites on the nerve terminal membrane. All these ligands are transported in the axons within smooth vesicles, cisternae, and tubules. In the cell bodies these membrane compartments fuse and most of the transported macromolecules are finally incorporated into lysosomes. The cell nuclei, the parallel golgi cisternae, and the extracellular space always remain unlabeled. In case the tetanus toxin, however, a substantial fraction of the labeled material appears in presynaptic cholinergic nerve terminals which innervate the labeled ganglion cells. In these terminals tetanus toxin-HRP is localized in 500-1,000 A diam vesicles. In contrast, such a retrograde transsynaptic transfer is not at all or only very rarely detectable after retrograde transport of cholera toxin, NGF, WGA, PHA, or ricin. An atoxic fragment of the tetanus toxin, which contains the ganglioside-binding site, behaves like intact toxin. With all these macromolecules, the extracellular space and the glial cells in the ganglion remain unlabeled. We conclude that the selectivity of this transsynaptic transfer of tetanus toxin is due to a selective release of the toxin from the postsynaptic dendrites. This release is immediately followed by an uptake into the presynaptic terminals. 相似文献
38.
FANNY VOGELWEITH DENIS THIERY YANNICK MORET JÉRÔME MOREAU 《Physiological Entomology》2013,38(3):219-225
Despite the obvious benefit of an immune system, its efficacy against pathogens and parasites may show great variation among individuals, populations and species. Understanding the causes of this variation is becoming a central theme in ecology. Many biotic and abiotic factors are known to influence immunocompetence (temperature, age, etc.). However, for a given age, size among individuals varies, probably as a result of accumulated resources. Thus, these variable resources could be allocated to immune defence and, consequently, body size may explain part of the variation in immune responsiveness. However, the influence of body size on immune defence is often overlooked. The present study investigates variations in haemocyte count and phenoloxidase activity in larvae of the phytophagous vine moth Eupoecilia ambiguella Hübner of the same age, although differing in body size. The measurements of immune function are made both when the insects are immunologically naïve and 24 h after a bacterial immune challenge. The base levels of these immune parameters do not covary with body size in naïve larvae. After the bacterial immune challenge, more haemocytes and phenoloxidase enzyme are mobilized, and the mobilization of these immune effectors is correlated positively with individual body size. Thus, larger larvae exhibit higher immunocompetence than smaller ones, suggesting that smaller larvae might be more vulnerable to infection. These results suggest that body size is probably an underestimated variable, which nevertheless modulates the insect immune system and should thus be considered as a covariate in insect immune system measurement. It is recommended therefore, that body size should be taken into account in ecological immunity studies with insects. © 2013 The Royal Entomological Society 相似文献
39.
The Cupper Mining Company (CMC)'s site located in Lefke-Gemikonagi, Northern Cyprus has been a continuous source of highly dangerous contamination for the surrounding environment, the Lefke region, and the neighboring ecosystems and settlements. Rehabilitation and reuse possibilities of the CMC site due to its vital importance have kept its place in the agenda of Northern Cyprus. Phytostabilization appears to be a convenient and less expensive method that can immediately be used for reducing the negative impacts of the mining site on the region. The main purpose of this study is to identify potential candidate plant species, adapted to grow on polluted sites, for revegetation in the CMC site. Within this context, the method of the study can be summarized as follows: literature review for examining potential candidate plant species for pyhtostabilization in arid and semiarid regions, especially the ones suitable both for the existing ecological and present conditions of Cyprus; identification of native and/or cultural plant species survived in the heavily polluted mining site, and definition of a number of candidate plant species for the study site. The result of sampling revealed that 23 plant species thrive well in the contaminated site. As a result of the literature review and considering drought, metal, salt tolerant features of semiarid environment in the region, 5 tree, 4 shrub, and 23 herbaceous plant species were proposed for starting revegetation with the purpose of phytostabilization on the CMC mining site. 相似文献
40.