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201.
202.
Physical mapping with large-insert clones is becoming an active area of genomics research, and capillary electrophoresis (CE) promises to revolutionize the physical mapping technology. Here, we demonstrate the utility of the CE technology for genome physical mapping with large-insert clones by constructing a robust, binary bacterial artificial chromosome (BIBAC)-based physical map of Penicillium chrysogenum. We fingerprinted 23.1× coverage BIBAC clones with five restriction enzymes and the SNaPshot kit containing four fluorescent-ddNTPs using the CE technology, and explored various strategies to construct quality physical maps. It was shown that the fingerprints labeled with one or two colors, resulting in 40–70 bands per clone, were assembled into much better quality maps than those labeled with three or four colors. The selection of fingerprinting enzymes was crucial to quality map construction. From the dataset labeled with ddTTP–dROX, we assembled a physical map for P.chrysogenum, with 2–3 contigs per chromosome and anchored the map to its chromosomes. This map represents the first physical map constructed using the CE technology, thus providing not only a platform for genomic studies of the penicillin-producing species, but also strategies for efficient use of the CE technology for genome physical mapping of plants, animals and microbes.  相似文献   
203.
In this study, we tested the hypothesis that spontaneously diabetic TallyHo (TH) mice, a novel polygenic model for type 2 diabetes, will exhibit endothelial dysfunction associated with an increased contribution from endothelium-derived contractile factors (EDCF). The cellular mechanisms underlying the increased contribution of EDCF were explored in 16 and 30-week-old male TH and age-matched male C57BL/6J mice (n=4-9). Blood glucose and serum lipid profiles were markedly increased in the TH mice. Superoxide generation, assessed with a lucigenin chemiluminescence assay, was markedly increased in the aortae of TH mice. Endothelium-dependent vascular relaxations and contractions to acetylcholine (ACh), but not endothelium-independent relaxations to sodium nitroprusside, were impaired and vascular contractions to phenylephrine were significantly enhanced in aortae from TH mice. Nomega-nitro-L-arginine methyl ester markedly increased the ACh-induced contractions in TH mice, whereas SQ29548, a thromboxane receptor antagonist, and cytochrome P450 (CYP) inhibitors 17-octadecynoic acid and sulfaphenazole, the latter being specific for CYP2C6 and 2C9, decreased and (or) normalized the contractile response to ACh in TH mice. The present study indicates that enhanced contribution of prostaglandin H2/thromboxane A2 receptor and CYP, likely CYP2C6 and 2C9, play a critical role in the pathogenesis of increased EDCF in the aortae of type 2 diabetic TH mice.  相似文献   
204.
Soluble guanylate cyclase (sGC) is an important downstream intracellular target of nitric oxide (NO) that is produced by endothelial NO synthase (eNOS) and inducible NO synthase (iNOS). In this study, we demonstrate that sGC exists in a complex with eNOS and heat shock protein 90 (HSP90) in aortic endothelial cells. In addition, we show that in aortic smooth muscle cells, sGC forms a complex with HSP90. Formation of the sGC/eNOS/HSP90 complex is increased in response to eNOS-activating agonists in a manner that depends on HSP90 activity. In vitro binding assays with glutathione S-transferase fusion proteins that contain the alpha- or beta-subunit of sGC show that the sGC beta-subunit interacts directly with HSP90 and indirectly with eNOS. Confocal immunofluorescent studies confirm the subcellular colocalization of sGC and HSP90 in both endothelial and smooth muscle cells. Complex formation of sGC with HSP90 facilitates responses to NO donors in cultured cells (cGMP accumulation) as well as in anesthetized rats (hypotension). These complexes likely function to stabilize sGC as well as to provide directed intracellular transfer of NO from NOS to sGC, thus preventing inactivation of NO by superoxide anion and formation of peroxynitrite, which is a toxic molecule that has been implicated in the pathology of several vascular diseases.  相似文献   
205.
&#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &#  &# 《水生生物学报》2014,38(1):137-141
为了阐明养殖环境对鱼类寄生指环虫群落的影响,研究调查了湖北省梁子湖和湖北省石首市养殖池塘中鲫鳃部寄生指环虫的种类和感染情况。在梁子湖中的野生鲫共发现6种指环虫,分别为坏鳃指环虫(Dactylogyrus vastator)、中型指环虫(D. intermedius)、弧形指环虫(D. arcuatus)、弓茎指环虫(D. baueri)、美丽指环虫(D. formosus)、望外指环虫(D. inexpeatatus);在养殖池塘中,除了望外指环虫外,其他5种指环虫均有发现。分析结果表明,来自于梁子湖野生鲫鳃部的坏鳃指环虫的平均丰度以及其他4种指环虫(不含望外指环虫)的感染率与平均丰度明显高于养殖池塘的。梁子湖中的指环虫群落平均物种丰富度、平均寄生虫数量以及Brillouin多样性指数都明显高于养殖池塘的;梁子湖野生鲫寄生指环虫的优势种是弧形指环虫(0.54),而池塘中的是坏鳃指环虫(0.76)。在宿主密度、种群大小、光照和溶氧等影响指环虫群落的因子中,溶氧可能是最主要因子。    相似文献   
206.
The effect of Ce3+ on the chlorophyll (chl) of spinach was studied in pot culture experiments. The results showed that Ce3+ could obviously stimulate the growth of spinach and increase its chlorophyll contents and photosynthetic rate. It could also improve the PSII formation and enhance its electron transport rate of PSII as well. By inductively coupled plasma-mass spectroscopy and atom absorption spectroscopy methods, it was revealed that the rare-earth-element (REE) distribution pattern in the Ce3+-treated spinach was leaf>root>shoot in Ce3+ contents. The spinach leaves easily absorbed REEs. The Ce3+ contents of chloroplast and chlorophyll of the Ce3+-treated spinach were higher than that of any other rare earth and were much higher than that of the control; it was also suggested that Ce3+ could enter the chloroplast and bind easily to chlorophyll and might replace magnesium to form Ce-chlorophyll. By ultraviolet-visible, Fourier transform infrared, and extended X-ray absorption fine structure (EXAFS) methods, Ce3+-coordinated nitrogen of porphyrin rings with eight coordination numbers and average length of the Ce-N bond of 0.251 nm.  相似文献   
207.
G protein coupled receptors (GPCRs) form homo- and hetero-dimers or -oligomers, which are functionally important. Lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) are bioactive lysophopholipids involved in diverse biological processes. We have examined homo- and hetero-dimerization among three major LPA receptors (LPA(1-3)), three major S1P receptors (S1P(1-3)), as well as OGR1 and GPR4. Using LacZ complementation assays, we have shown that LPA receptors form homo- and hetero-dimers within the LPA receptor subgroup and hetero-dimers with other receptors (S1P(1-3) and GPR4). In addition, we have found that although GPR4 and OGR1 share more than 50% homology, GPR4 forms strong homo- and hetero-dimers with LPA and S1P receptors, but OGR1 forms very weak homo-dimer and relatively weak hetero-dimers with other receptors. Using chimeric receptors between GPR4 and OGR1, we have shown that different domains of GPR4 receptor are involved in its dimerization with different GPCRs and more than one domain may be involved in some of the complex formation. Our results suggest that when studying a signal transduction induced by a stimulus, not only is the expression and activation of its own receptor(s), but also the status of the interacting receptors should be taken into consideration.  相似文献   
208.
江洪  张朝晖 《广西植物》2007,27(4):610-615
利用原子吸收光谱仪对晴隆老万场红土型金矿三种苔藓植物体及其土壤中Au、Ca、Mg、Cu、Pb、Tl、Zn、Hg八种金属元素进行测定,并对植物体与元素之间的相关性及植物对金属的富集能力进行分析。结果表明:在该金矿区生长的苔藓体内金属元素普遍比较高,其体内金属元素含量的顺序与土壤中的金属元素的顺序基本一致。不同物种植物体对金属元素的吸收、富集却有较大的差异。Mg-Hg在0.01水平上达到极显著正相关,Au-Zn、Tl-Cu在0.05水平上达到显著正相关。皱叶毛口藓和芽孢银藓对Au具有较强的富集能力,因此,它们在该地区对红土型金矿具有一定的指示作用。  相似文献   
209.
A wide range of host cellular signal transduction pathways can be stimulated by influenza virus infection. Some of these signal transduction pathways induce the host cell’s innate immune response against influenza virus, while others are essential for efficient influenza virus replication. This review examines the cellular signaling induced by influenza virus infection in host cells, including host pattern recognition receptor (PRR)-related signaling, protein kinase C (PKC), Raf/MEK/ERK and phosphatidylinositol- 3-kinase (PI3K)/Akt signaling, and the corresponding effects on the host cell and/or virus, such as recognition of virus by the host cell, viral absorption and entry, viral ribonucleoprotein (vRNP) export, translation control of cellular and viral proteins, and virus-induced cell apoptosis. Research into influenza virus-induced cell signaling promotes a clearer understanding of influenza virus-host interactions and assists in the identification of novel antiviral targets and antiviral strategies.  相似文献   
210.
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