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971.
Chun Tang Yun Li Xiaojun Lin Jinghua Ye Weinian Li Zhixiang He Fangfei Li Xiaoyan Cai 《Cellular immunology》2014
Tumor necrosis factor (TNF)-α is one of the major proinflammatory mediators of rheumatic arthritis (RA); the regulatory factors for TNF-α release is not fully understood. This study aims to investigate the role of prolactin receptor (PRLR) activation in regulating the expression and release of TNF-α from CD14+ monocytes. The results showed that the expression of PRLR was detectable in CD14+ monocytes of healthy subjects, which was markedly increased in RA patients. Exposure to PRL in the culture increased the expression and release of TNF-α from CD14+ monocytes, which was abolished by the PRLR gene silencing or blocking the mitogen activated protein (MAPK) pathway. We conclude that exposure to PRL increases TNF-α release from CD14+ monocytes of RA patients, which can be abolished by PRLR gene silencing or treating with MAPK inhibitor. 相似文献
972.
973.
With different prevalence in different regions, radio frequency (RF) electromagnetic fields (EMF) are widely used for therapeutic tissue heating. Although short‐wave diathermy (27.12 MHz) is the most popular treatment modality, quantitative data on patient's exposure have been lacking. By numerical simulation with the numerical anatomical model NORMAN, intracorporal distributions of specific absorption rates (SAR) were investigated for different treatment scenarios and applicators. Quantitative data are provided for exposures of target treatment areas as well as for vulnerable regions such as the eye lenses, central nervous system, and testes. Different applicators and distances were investigated. Capacitive and inductive applicators exhibit quite a different heating efficiency. It could be shown that for the same output power therapeutic heat deposition can vary by almost one order of magnitude. By mimicking therapist's practice to use patient's heat perception as an indicator for output power setting, numerical data were elaborated demonstrating that muscle tissue exposures may be several times higher for inductive than for capacitive applicators. Presented quantitative data serve as a guide for power adjustment preventing relevant overexposures without compromising therapy; they also provide a basis for estimating target tissue heat load and developing therapeutic guidelines. Bioelectromagnetics 31:12–19, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
974.
夏季舟山渔场及邻近海域浮游动物群落结构特征分析 总被引:5,自引:0,他引:5
2006年8月在舟山渔场及邻近海域(29°30′ ~31°30′ N,124°30′ E以西)开展海洋生态系统综合调查,用浅水Ⅰ型浮游生物网采集的浮游动物样本,对该海域浮游动物的种类组成、数量分布、生物多样性等群落结构特征进行了分析。结果得知,在调查海域共鉴定出浮游动物93种(不包含浮游幼虫),其中以桡足类的种类数为最多,有50种,优势种主要有精致真刺水蚤(Euchaeta concinna)、软拟海樽(Dolioletta gegenbauri)、肥胖箭虫(Sagitta enflata)、百陶箭虫(Sagitta bedoti)、中华哲水蚤(Calanus sinicus)、普通波水蚤(Undinula vulgaris)、微刺哲水蚤(Canthocalanus paupe)、长尾类幼虫(Macruran larvae)、双生水母(Diphyes chamissonis)、背针胸刺水蚤(Centropages dorsispinatus)、肥胖三角溞(Evadne tergestina)、太平洋纺锤水蚤(Acartia pacifica)等12种。调查海域浮游动物丰度平面分布呈现南部高、北部低,近岸高、外海低的特征。生物多样性分析表明,调查海域浮游动物种类数较多,且具有较高的均匀度(0.70),因此其生物多样性指数较高(4.98)。根据聚类分析结果,可将夏季调查海域的浮游动物在17.13%相似性水平上分为A、B、C三个组群。生物8722;环境匹配分析显示,浮游动物的丰度除了与表层盐度、硝酸氮和硅酸盐含量有关外,还与镉、铅的含量存在着一定相关性。 相似文献
975.
Effects of age and orientation of the explant on callus induction and de novo shoot regeneration from cotyledonary leaf segments of Jatropha curcas were studied. The callus induction and shoot regeneration capacity of cotyledonary leaf segments were found significantly related to the age of the explants and their orientation in culture medium. The youngest explant, derived from the cotyledonary leaf of germinated seed induced the highest regeneration response as compared to one- and two-week-old explants. A gradient response with age of the explant was observed in percentage of callus induction, shoot regeneration from callus and the number of shoots per regenerating callus. The explants cultured with their abaxial side in medium showed significantly higher regeneration response. The youngest explant was found to be most amenable to Agrobacterium-mediated transformation as compared to older explants. The fact that callus induced from the edges of the explant followed by de novo shoot induction, and strong transient gus expression observed in the edges of the explant are significant for routine Agrobacterium-mediated transformation and generation of stable transgenic plants in J. curcas. 相似文献
976.
A quantitative real-time PCR method for in planta monitoring of Phytophthora infestans growth 总被引:1,自引:0,他引:1
Llorente B Bravo-Almonacid F Cvitanich C Orlowska E Torres HN Flawiá MM Alonso GD 《Letters in applied microbiology》2010,51(6):603-610
Aim: To develop a real‐time PCR‐based strategy for the detection of Paenibacillus larvae vegetative cells and spores to improve the diagnosis and the screening of American foulbrood (AFB), the most harmful pathology of honeybee brood. Methods and Results: A real‐time PCR that allowed selective identification and quantification of P. larvae 16S rRNA sequence was developed. Using standard samples quantified by flow cytometry, detection limits of 37·5 vegetative cells ml?1 and 10 spores ml?1 were determined. Compared to spread plate method, this real‐time PCR‐based strategy allowed, in only 2 h, the detection of P. larvae in contaminated honeys. No false‐positive results were obtained. Moreover, its detection limit was 100 times lower than that of the culture method (2 vs 200 spores g?1 of honey). Conclusion: A rapid, selective, with low detection limit, sensitive and specific method to detect and quantify vegetative cells and spores of P. larvae is now available. Significance and Impact of Study: In addition to honey samples, this real‐time PCR‐based strategy may be also applied to confirm AFB diagnosis in honeybee brood and to screen other apiary supplies and products (bees, pollen, wax), thus broadening the control of AFB spreading. 相似文献
977.
Background
The concentration of iron in the brain increases with aging. Furthermore, it has also been observed that patients suffering from neurological diseases (e.g. Parkinson, Alzheimer…) accumulate iron in the brain regions affected by the disease. Nevertheless, it is still not clear whether this accumulation is the initial cause or a secondary consequence of the disease. Free iron excess may be an oxidative stress source causing cell damage if it is not correctly stored in ferritin cores as a ferric iron oxide redox-inert form.Scope
Both, the composition of ferritin cores and their location at subcellular level have been studied using analytical transmission electron microscopy in brain tissues from progressive supranuclear palsy (PSP) and Alzheimer disease (AD) patients.Major conclusions
Ferritin has been mainly found in oligodendrocytes and in dystrophic myelinated axons from the neuropili in AD. In relation to the biomineralization of iron inside the ferritin shell, several different crystalline structures have been observed in the study of physiological and pathological ferritin. Two cubic mixed ferric–ferrous iron oxides are the major components of pathological ferritins whereas ferrihydrite, a hexagonal ferric iron oxide, is the major component of physiological ferritin. We hypothesize a dysfunction of ferritin in its ferroxidase activity.General significance
The different mineralization of iron inside ferritin may be related to oxidative stress in olygodendrocites, which could affect myelination processes with the consequent perturbation of information transference. 相似文献978.
A number of studies now point to the association of patterns of phylogeography with discontinuities in coastal current patterns. If such phylogeographic patterns are indicative of populations that retain local diversity, as has been predicted by recent modelling, such results may be of use in marine reserve planning. Here we show that there is a distributional correlation on the Pacific coast of North America between marine reserve placement and phylogeographic patterns. A number of factors could contribute to this correlation, but its existence suggests the utility of genetic studies in marine conservation planning. 相似文献
979.
We provide the first direct evidence that Steller sea lions will prey on harbor seals. Direct observations of predation on marine mammals at sea are rare, but when observed rates of predation are extrapolated, predation mortality may be found to be significant. From 1992 to 2002, harbor seals in Glacier Bay declined steeply, from 6,200 to 2,500 (∼65%). After documenting that Steller sea lions were preying on seals in Glacier Bay, we investigated increased predation by sea lions as a potential explanation for the large decline. In five independent data sets spanning 21–25 yr and including 14,308 d of observations, 13 predation events were recorded. We conducted a fine-scale analysis for an intensively studied haul-out (Spider Island) and a broader analysis of all of Glacier Bay. At Spider Island, estimated predation by sea lions increased and could account for the entirety of annual pup production in 5 of 8 yr since 1995. The predation rate, however, was not proportional to the number of predators. Predation by Steller sea lions is a new source of mortality that contributed to the seal declines; however, life history modeling indicates that it is unlikely that sea lion predation is the sole factor responsible for the large declines. 相似文献
980.
One of the major bottlenecks in many ab initio protein structure prediction methods is currently the selection of a small number of candidate structures for high‐resolution refinement from large sets of low‐resolution decoys. This step often includes a scoring by low‐resolution energy functions and a clustering of conformations by their pairwise root mean square deviations (RMSDs). As an efficient selection is crucial to reduce the overall computational cost of the predictions, any improvement in this direction can increase the overall performance of the predictions and the range of protein structures that can be predicted. We show here that the use of structural profiles, which can be predicted with good accuracy from the amino acid sequences of proteins, provides an efficient means to identify good candidate structures. Proteins 2010. © 2009 Wiley‐Liss, Inc. 相似文献