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991.
Eutrophication assessment and bioremediation strategy in a marine fish cage culture area in Nansha Bay,China 总被引:3,自引:0,他引:3
On the basis of field data measured during four cruises from January to November 2007, variations in the characteristics of
dissolved inorganic nitrogen and phosphate were analyzed in Nansha marine fish cage culture area, Ningbo City, China. Dissolved
inorganic nitrogen (DIN) was selected as the parameter to balance seaweed absorption and fish DIN production. The contents
of DIN and phosphate varied with different seasons, and eutrophication index (E) value ranged from 2.41 to 15.99, indicating serious eutrophication conditions; the annual average value of N/P of 32.95
indicates a nitrogen surplus in this system. The eutrophication condition in Nansha Bay was mainly caused by the fish cage
culture activities. Based on their biological characteristics, Laminaria and Gracilaria were selected as the bioremediation species in winter and spring and summer and autumn, respectively. The optimal co-cultivation
proportion of fish cage to Laminaria and Gracilaria in this bay was 1 cage, 450 m2 and one cage, 690 m2, respectively. 相似文献
992.
Receptor‐like kinase OsSIK1 improves drought and salt stress tolerance in rice (Oryza sativa) plants
Shou‐Qiang Ouyang Yun‐Feng Liu Peng Liu Gang Lei Si‐Jie He Biao Ma Wan‐Ke Zhang Jin‐Song Zhang Shou‐Yi Chen 《The Plant journal : for cell and molecular biology》2010,62(2):316-329
Receptor‐like kinases (RLKs) play essential roles in plant growth, development and responses to environmental stresses. A putative RLK gene, OsSIK1, with extracellular leucine‐rich repeats was cloned and characterized in rice (Oryza sativa). OsSIK1 exhibits kinase activity in the presence of Mn2+, and the OsSIK1 kinase domain has the ability to autophosphorylate and phosphorylate myelin basic protein (MBP). OsSIK1 promoter‐GUS analysis revealed that OsSIK1 is expressed mainly in the stem and spikelet in rice. The expression of OsSIK1 is mainly induced by salt, drought and H2O2 treatments. Transgenic rice plants with overexpression of OsSIK1 show higher tolerance to salt and drought stresses than control plants. On the contrary, the knock‐out mutants sik1‐1 and sik1‐2, as well as RNA interference (RNAi) plants, are sensitive to drought and salt stresses. The activities of peroxidase, superoxide dismutase and catalase are enhanced significantly in OsSIK1‐overexpressing plants. Also, the accumulation of H2O2 in leaves of OsSIK1‐overexpressing plants is much less than that of the mutants, RNAi plants and control plants, as measured by 3,3′‐diamino benzidine (DAB) staining. We also show that OsSIK1 affects stomatal density in the abaxial and adaxial leaf epidermis of rice. These results indicate that OsSIK1 plays important roles in salt and drought stress tolerance in rice, through the activation of the antioxidative system. 相似文献
993.
Li-Xia Cheng Jiang-Jiang Tang Hui Luo Xiao-Ling Jin Fang Dai Jie Yang Yi-Ping Qian Xiu-Zhuang Li Bo Zhou 《Bioorganic & medicinal chemistry letters》2010,20(8):2417-2420
Eight hydroxyl-substituted Schiff bases with the different number and position of hydroxyl group on the two asymmetric aromatic rings (A and B rings) were prepared by the reaction between the corresponding aromatic aldehyde and aniline. Their antioxidant effects against the stable galvinoxyl radical (GO) in ethyl acetate and methanol, and 2,2′-azobis(2-amidinopropane hydrochloride) (AAPH)-induced DNA strand breakage, and their antiproliferative effects on human hepatoma HepG2 cells, were investigated. Structure–activity relationship analysis demonstrates that o-dihydroxyl groups on the aromatic A ring and 4-hydroxyl group attached to the aromatic B ring contribute critically to the antioxidant and antiproliferative activities. 相似文献
994.
Wei Li Yi-Min Tao Yun Tang Xue-Jun Xu Jie Chen Wei Fu Xing-Hai Wang Bo Chao Wei Sheng Qiong Xie Zhui-Bai Qiu Jing-Gen Liu 《Bioorganic & medicinal chemistry letters》2010,20(1):418-421
Unexpected substituent on the well-known morphine skeleton is described to be account for highly selective and potent μ opioid ligands, which is strongly connected to substituted aromatic groups on this omitted 8α-position. 相似文献
995.
Xuefei Tan Richland W. Tester Gregory R. Luedtke Sarvajit Chakravarty Babu J. Mavunkel John J. Perumattam Qing Lu Imad Nashashibi Joon Jung Jie Hu Albert Liclican Ramona Almirez Jocelyn Tabora Vinh Tran Maureen Laney Daniel E. Levy Sundeep Dugar 《Bioorganic & medicinal chemistry letters》2010,20(3):828-831
Derivatives of the 4-fluorobenzyl dimethylpiperazine-indole class of p38α MAP kinase inhibitors are described. Biological evaluation of these compounds focused on maintaining activity while improving pharmacokinetic (PK) properties. Improved properties were observed for structures bearing substitutions on the benzylic methylene. 相似文献
996.
Slater L Bartlett NW Haas JJ Zhu J Message SD Walton RP Sykes A Dahdaleh S Clarke DL Belvisi MG Kon OM Fujita T Jeffery PK Johnston SL Edwards MR 《PLoS pathogens》2010,6(11):e1001178
The relative roles of the endosomal TLR3/7/8 versus the intracellular RNA helicases RIG-I and MDA5 in viral infection is much debated. We investigated the roles of each pattern recognition receptor in rhinovirus infection using primary bronchial epithelial cells. TLR3 was constitutively expressed; however, RIG-I and MDA5 were inducible by 8-12 h following rhinovirus infection. Bronchial epithelial tissue from normal volunteers challenged with rhinovirus in vivo exhibited low levels of RIG-I and MDA5 that were increased at day 4 post infection. Inhibition of TLR3, RIG-I and MDA5 by siRNA reduced innate cytokine mRNA, and increased rhinovirus replication. Inhibition of TLR3 and TRIF using siRNA reduced rhinovirus induced RNA helicases. Furthermore, IFNAR1 deficient mice exhibited RIG-I and MDA5 induction early during RV1B infection in an interferon independent manner. Hence anti-viral defense within bronchial epithelium requires co-ordinated recognition of rhinovirus infection, initially via TLR3/TRIF and later via inducible RNA helicases. 相似文献
997.
Lu Dong Jie Zhang Yue Sun Ying Liu Yanyun Zhang Guangmei Zheng 《Conservation Genetics》2010,11(6):2231-2242
Cabot’s tragopan (Tragopan caboti) is a pheasant endemic to southeast China and is protected under both national and global legislation due to ongoing decline
in population size and increased habitat fragmentation. We investigated the phylogeographic patterns and examined the consistency
between evolutionary units and assumed subspecies taxonomy in this species. Six populations across the whole species presenting
a wide distribution range were sampled and two mitochondrial DNA segments (control region, CR and cytochrome b, cyt b) were used in this study. The results demonstrated a high level of genetic diversity (h = 0.97 in CR and 0.78 in cyt b) and significant differentiation among populations. Phylogenetic analyses strongly indicated two reciprocally monophyletic
clades named the “West group” and “East group” that were not consistent with the present subspecies regional distribution.
The divergence time between the two groups was estimated to be around 5.54 × 105–8.7 × 105 years ago, and the expansion times of the two groups were close (about 3 × 105 years ago), indicating the effect of glaciation in intraspecific differentiation. Based on the results of genetic analyses
combined with geographic isolation and distinct population history, our findings suggest that two management units (MUs) should
be defined in T. caboti for conservation. 相似文献
998.
Yuanwei Jia Haitang Xie Guangji Wang Jianguo Sun Wei Wang Huang Qing Xuan Wang Hao Yang Meijuan Xu Yi Gu Chen Yao Jie Shen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(9-10):791-797
A simple liquid chromatography electrospray ionization mass spectrometry (LC–ESI–MS) method with highly improved sensitivities for the determination of helicid in rat bile, urine, feces and most tissues was developed. The tissues and feces were firstly homogenized mechanically using deionized water as the media. Bile, urine, tissues and feces homogenates were extracted by liquid–liquid extraction with n-butyl alcohol for sample preparation. The subsequent analysis procedures were performed on a Shimadzu LCMS2010A system (electrospray ionization single quadrupole mass analyzer). A Luna C18 column (150 mm × 2.00 mm, 5 μm) was used as the analytical column, while a mixture of acetonitrile and ammonium chloride water solution was used as the mobile phase. The proportions of mobile phase were changed timely according to gradient programs. Chlorinated adducts of molecular ions [M+Cl]? at m/z 319.00 and 363.05 were used to quantify helicid and bergeninum (internal standard), respectively. The method was validated to be accurate, precise and rugged with good linearity. The proposed method was successfully applied to the preclinical tissue distribution and excretion studies of helicid in rats. 相似文献
999.
Meng Sun Jing Ren Hui Du Yanmin Zhang Jie Zhang Sicen Wang Langchong He 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(28):2712-2718
We have developed an online analytical method that combines A431 cell membrane chromatography (A431/CMC) with high performance liquid chromatography and mass spectrometry (LC/MS) for identifying active components from Radix Caulophylli acting on human EGFR. Retention fractions on A431/CMC model were captured onto an enrichment column and the components were directly analyzed by combining a 10-port column switcher with an LC/MS system for separation and preliminary identification. Using Sorafenib tosylate as a positive control, taspine and caulophine from Radix Caulophylli were identified as the active molecules which could act on the EGFR. This A431/CMC-online-LC/MS method can be applied for screening active components acting on EGFR from traditional Chinese medicines exemplified by Radix Caulophylli and will be of great utility in drug discovery using natural medicinal herbs as a source of novel compounds. 相似文献
1000.
Rui Du Lin Xia Shiren Sun Zhaorui Lian Xue Zou Juan Gao Huahong Xie Rui Fan Jiugang Song Xiaohua Li Jie Liu Daiming Fan 《Journal of cellular and molecular medicine》2010,14(3):621-635
Upregulated gene 11 (URG11), a new gene upregulated by Heptatitis B Virus X protein (HBx), was previously shown to activate β‐catenin and promote hepatocellular growth and tumourigenesis. Although the oncogenic role of URG11 in the development of hepatocellular carcinoma has been well documented, its relevance to other human malignancies and the underlying molecular mechanisms remain largely unknown. Here we reported a novel function of URG11 to promote gastric cancer growth and metastasis. URG11 was found to be highly expressed in gastric cancer tissues compared with adjacent nontumourous ones by immunohistochemical staining and western blot. Knockdown of URG11 expression by small interfering RNA (siRNA) effectively attenuated the proliferation, anchorage‐independent growth, invasiveness and metastatic potential of gastric cancer cells. URG11 inhibition led to decreased expression of β‐catenin and its nuclear accumulation in gastric cancer cells and extensive costaining between URG11 and β‐catenin was observed in gastric cancer tissues. Transient transfection assays with the β‐catenin promoter showed that it was inhibited by URG11‐specific small inhibitory RNA. Moreover, suppression of endogenous URG11 expression results in decreased activation of β‐catenin/TCF and its downstream effector genes, cyclinD1 and membrane type 1 matrix metallopeptidase (MT1‐MMP), which are known to be involved in cell proliferation and invasion, respectively. Taken together, our data suggest that URG11 contributes to gastric cancer growth and metastasis at least partially through activation of β‐catenin signalling pathway. These findings also propose a promising target for gene therapy in gastric cancer. 相似文献