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891.
Larval settlement and metamorphosis of the mussel Mytilus coruscus in response to natural biofilms 总被引:1,自引:0,他引:1
Settlement and metamorphosis of pediveliger larvae of Mytilus coruscus in response to natural biofilms was investigated in the laboratory. Pediveliger larvae settled and metamorphosed in response to biofilms and post-larval settlement and metamorphosis increased with biofilm age. The activity of the biofilm was positively correlated with biofilm age, dry weight, bacterial density and diatom density, but had no apparent relationship with chlorophyll a concentration. The change in bacterial community composition corresponding to biofilm age may explain differences in the age-dependent inducing activities of biofilms, which in turn may play an important role in larval settlement in this species. 相似文献
892.
Xiu L. Feng Qing T. Liu Rui B. Cao Bin Zhou De Y. Li Yuan P. Zhang Ke Liu Xiao D. Liu Jian C. Wei Ya F. Qiu Xin F. Li Zhi Y. Ma Pu Y. Chen 《Amino acids》2012,43(6):2443-2456
Bursa of Fabricius is the acknowledged vital humoral immune system for B cell differentiation and antibody production. To study the molecular mechanism underlying the effect of bursal-derived BP5, we used gene microarray to analyze the genomic expression profiling of BP5-treated hybridoma cells. BP5 exhibited an immunomodulatory effect on antibody production in hybridoma cells and induced alterations in the gene expression profiles related to the immune-related biological processes, such as T cell activation and proliferation, B cell activation, B cell-mediated immunity, and cytokines cytokine production involved in immune response. In addition, 26 biological pathways associated with immunomodulatory functions were regulated in BP5-treated hybridoma cells, in which p53 signal pathway played an important role in antitumor. Among these regulated genes, 12 differentially expressed genes were verified by qRT-PCR. The activation of p53 activity by BP5 was further confirmed by p53 luciferase reporter assay and p53 expression. Our data revealed that bursal-derived BP5 could regulate various immune-related cellular processes, including antitumor factor p53 signal pathway, perhaps partially accounting for the reported immunomodulatory roles and novel antiproliferation on tumor cells functions of bursal-derived bioactive factor BP5. 相似文献
893.
894.
机械拉伸下人肺上皮细胞增殖及整联蛋白再分布 总被引:8,自引:0,他引:8
应用体外周期性拉伸装置研究机械拉伸对人肺上皮细胞A5 4 9增殖及其膜表面受体———整联蛋白α5、β1再分布的调控作用。结果表明 :在应变为 15 % ,频率为 2 0次 /min、4 0次 /min的拉伸刺激下 ,4 8h后 ,应用流式细胞技术检测细胞的增殖活性指数明显降低 ,A5 4 9细胞的DNA合成受到显著抑制。在 4 0次 /min的拉伸频率下 ,整联蛋白α5、β1的分布发生重组并向基底层转移 ,形成局部粘附连接。研究表明 :整联蛋白α5、β1可能在肺上皮细胞感应机械应力过程中起了重要的作用。 相似文献
895.
Yujiao Mao Jingjing Wei Qiang Zheng Na Xiao Qipei Li Yingnan Fu Yanan Wang Nianzhi Jiao 《Current microbiology》2012,65(5):568-574
A novel aerobic, bacteriochlorophyll-containing bacteria strain JLT1202rT was isolated from Beibu Gulf in the South China Sea. Cells were gram-negative, non-motile, and short-ovoid to rod-shaped with two narrower poles. Strain JLT1202rT formed circular, opaque, wine-red colonies, and grew optimally at 3–4?% NaCl, pH 7.5–8.0 and 28–30?°C. The strain was catalase, oxidase, ONPG, gelatin, and Voges–Proskauer test positive. In vivo absorption spectrum of bacteriochlorophyll a presented two peaks at 800 and 877?nm. The predominant cellular fatty acid was C18:1 ω7c and significant amounts of C16:0, C18:0, C10:0 3-OH, C16:0 2-OH, and 11-methyl C18:1 ω7c were present. Strain JLT1202rT contained Q-10 as the major respiratory quinone and the genomic DNA G+C content was 76.3?mol%. Phylogenetic analysis based on 16S rRNA gene sequences of various species with validly published names showed that strain JLT1202rT fell within the genus Roseibacterium, family Rhodobacteraceae, sharing the highest similarity with Roseibacterium elongatum OCh 323T (97.9?% similarity), followed by Dinoroseobacter shibae DFL 12T (95.4?% similarity). The phylogenetic distance of pufM genes between strain JLT1202rT and R. elongatum OCh 323T was 9.4?%, suggesting that strain JLT1202rT was distinct from the only strain of the genus Roseibacterium. Based on the variabilities of phylogenetic and phenotypic characteristics, strain JLT1202rT stands for a novel species of the genus Roseibacterium and the name R. beibuensis sp. nov. is proposed with JLT1202rT as the type strain (=JCM 18015T?=?CGMCC 1.10994T). 相似文献
896.
Moireau P Xiao N Astorino M Figueroa CA Chapelle D Taylor CA Gerbeau JF 《Biomechanics and modeling in mechanobiology》2012,11(1-2):1-18
The objective of this work is to address the formulation of an adequate model of the external tissue environment when studying a portion of the arterial tree with fluid–structure interaction. Whereas much work has already been accomplished concerning flow and pressure boundary conditions associated with truncations in the fluid domain, very few studies take into account the tissues surrounding the region of interest to derive adequate boundary conditions for the solid domain. In this paper, we propose to model the effect of external tissues by introducing viscoelastic support conditions along the artery wall, with two—possibly distributed—parameters that can be adjusted to mimic the response of various physiological tissues. In order to illustrate the versatility and effectiveness of our approach, we apply this strategy to perform patient-specific modeling of thoracic aortae based on clinical data, in two different cases and using a distinct fluid–structure interaction methodology for each, namely an Arbitrary Lagrangian–Eulerian (ALE) approach with prescribed inlet motion in the first case and the coupled momentum method in the second case. In both cases, the resulting simulations are quantitatively assessed by detailed comparisons with dynamic image sequences, and the model results are shown to be in very good adequacy with the data. 相似文献
897.
Na+通道存在于胰腺胰岛β细胞上;相对其它可兴奋细胞上的Na+通道,有其特殊的生理特性和功能.研究发现β细胞上的Na+通道影响了β细胞的动作电位,并可能参与胰岛素的分泌调节.但是目前对于Na+通道在β细胞上的功能还存在着很大的争议.随着新的研究技术的发展,有必要为目前对β细胞Na+通道的研究进行综述,这对于进一步研究β细胞上Na+通道的功能具有重要的指导意义. 相似文献
898.
Xiao K Li X Li J Ma L Hu B Yu H Fu Y Wang R Ma Z Qiu B Li J Hu D Wang X Shen J 《Bioorganic & medicinal chemistry》2006,14(13):4535-4551
With the aim of developing small molecular non-peptide beta-secretase (BACE) inhibitors, Leu*Ala hydroxyethylene (HE) was investigated as a scaffold to design and synthesize a series of compounds. Taking advantage of efficient combinatorial synthesis approaches and molecular modeling, extensive structure-activity relationship (SAR) studies were carried out on the N- and C-terminal residues of the Leu*Ala HE scaffold. Isobutyl amine was found to be an optimal C-cap, and suitable hydroxylalkylamines at the 3-position and nitro or methyl(methylsulfonyl)amine at the 5-position of isophthalamide as the N-terminus could form additional hydrogen bonds with BACE active sites and help improve potency. Many new potent non-peptide BACE inhibitors were identified in this study. Among them, compounds 37 and 44 exhibited excellent enzyme-inhibiting potency, comparable to that of OM99-2, and obvious inhibitory effects in cell-based assay with low molecular weights (<600). 相似文献
899.
Objective
To evaluate the reports'' qualities which are about randomized controlled trials (RCTs) of acupuncture treatment on Mild Cognitive Impairment (MIC).Methods
Nine databases including the Cochrane Central Register of Controlled Trials (CENTRAL,2010), PUBMED (1984-5/2010), EMbase (1984-5/2010), MEDLINE (1984-5/2010), CINAL (1984-5/2010), China National Knowledge Infrastructure (CNKI, 1980-5/2010), China Biomedicine Database disc (CBMdisc, 1980-5/2010), VIP (a full text issues database of China, 1989-5/2010) were searched systematically. Hand search for further references was conducted. Language was limited to Chinese and English. We identified 14 RCTs that used acupuncture as an intervention and assessed the quality of these reports against the Consolidated Standards for Reporting of Trials (CONSORT) statement and Standards for Reporting Interventions in Controlled Trials of Acupuncture (STRICTA).Results
In regard to the items in the CONSORT statement, 13(92.86%) RCTs described baseline demographic and clinical characteristics in each group. 7 (50.0%) mentioned the method of generating the random sequence, only 2 (14.3%) RCTs had adequate allocation concealment. No RCTs used blinding. RCTs reported the sample size calculation. In regard to the items in STRICTA, 10 (71.43%) mentioned the depths of insertion, 6 (42.86%) reported acupuncture response, 11 (78.57%) mentioned the technique of acupuncture, 12 (85.71%) recorded the time, and only 3 (21.43%) RCTs reported the numbers of needles inserted. No RCTs reported the background of the acupuncture practitioners and professional title of practitioners.Conclusion
The reporting quality of RCTs of acupuncture for mild cognitive impairment was moderate to low. The CONSORT statement and STRICTA should be used to standardize the reporting of RCTs of acupuncture in future. 相似文献900.
衰老是任何生物都无法避免的生理现象,它由多种因素引起,其过程极其复杂.酵母细胞是目前衰老研究领域公认的模式生物,一系列影响衰老的分子作用机理及调控因素的发现均源自于对酵母细胞的研究.自然衰老是酵母细胞的衰老模式之一,由于该衰老过程与其他高等真核细胞(特别是哺乳动物细胞)极为相似,近年来受到广泛关注.全面比较酵母细胞衰老的两种模式,详细介绍自然衰老过程中分子作用机理的研究进展,重点阐述其复杂的自然寿命调控通路,包括卡路里限制以及药物添加对Ras/PKA、Sch9、Tor等营养依赖型调控通路的影响,并展望未来该领域需要解决的重要科学问题,为全面深入了解高等生物,特别是人类自身的衰老机理提供参考. 相似文献