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991.
Sang-im Lee Kyungseon Seo Wonyoung Lee Woohjung Kim Jae Chun Choe Piotr Jabłoński 《Journal of Ethology》2011,29(3):401-407
We report the first case of non-parental infanticide in the Black-billed Magpie Pica pica. Using a video camera installed in the victims’ nest, we recorded repeated visits (over 4 days) of an adult (each time one
bird) who attacked six nestlings at each visit until they died or were evicted. The nest was one of 58 nests filmed over four
breeding seasons. Collected evidence suggests that the perpetrator(s) might have been the female breeder of the neighbouring
nest, possibly also her male partner. The parental female aggressively attacked the perpetrator. Post-infanticide expansion
of breeding territory by the suspected perpetrator is the hypothetical ultimate explanation of the observed infanticide. Movie
clips from inside the nest are shown at: , , , and . 相似文献
992.
993.
994.
Chang JH Cha HR Chang SY Ko HJ Seo SU Kweon MN 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(12):6999-7005
Although the induction mechanism of secretory IgA has been well studied, that of IgG in the mucosal compartments is not well understood. In this study, vitamin A deficiency was convincingly shown to be associated with increased IgG in serum and intestinal fluid. We found increased numbers of IgG-secreting B cells in the lamina propria of the small intestine and mesenteric lymph node (MLN) of vitamin A-deficient (VAD) mice. Of note, IFN-γ secreted by MLN dendritic cells (DCs) was significantly augmented in VAD mice, unlike control mice, and CD103(+) DCs were the main subsets to secrete IFN-γ. The aberrant increase of IgG in VAD mice can be ascribable to IFN-γ, because IFN-γ(-/-) VAD mice have normal IgG levels and the addition of rIFN-γ increased IgG production by B cells cocultured with MLN DCs from IFN-γ(-/-) VAD mice. Oral feeding of antibiotics resulted in significant reduction of IgG in VAD mice, indicating a critical role for altered commensal bacteria for IgG class-switching recombination in the absence of vitamin A. Collectively, vitamin A deficiency provokes the generation of IFN-γ-secreting CD103(+) DCs, which may be a critical regulator for IgG generation in the MLN. 相似文献
995.
Iwakura Y Wang R Abe Y Piao YS Shishido Y Higashiyama S Takei N Nawa H 《Journal of neurochemistry》2011,118(1):57-68
Epidermal growth factor (EGF) and structurally related peptides promote neuronal survival and the development of midbrain dopaminergic neurons; however, the regulation of their production has not been fully elucidated. In this study, we found that the treatment of striatal cells with dopamine agonists enhances EGF release both in vivo and in vitro. We prepared neuron-enriched and non-neuronal cell-enriched cultures from the striatum of rat embryos and challenged those with various neurotransmitters or dopamine receptor agonists. Dopamine and a dopamine D(1) -like receptor agonist (SKF38393) triggered EGF release from neuron-enriched cultures in a dose-dependent manner. A D(2) -like agonist (quinpirole) increased EGF release only from non-neuronal cell-enriched cultures. The EGF release from striatal neurons and non-neuronal cells was concomitant with ErbB1 phosphorylation and/or with the activation of a disintegrin and metalloproteinase and matrix metalloproteinase. The EGF release from neurons was attenuated by an a disintegrin and metalloproteinase/matrix metalloproteinase inhibitor, GM6001, and a calcium ion chelator, BAPTA/AM. Transfection of cultured striatal neurons with alkaline phosphatase-tagged EGF precursor cDNA confirmed that dopamine D(1) -like receptor stimulation promoted both ectodomain shedding of the precursor and EGF release. Therefore, the activation of striatal dopamine receptors induces shedding and release of EGF to provide a retrograde neurotrophic signal to midbrain dopaminergic neurons. 相似文献
996.
Sim S Lee WJ Yu JR Lee IY Lee SH Oh SY Seo M Chai JY 《The Korean journal of parasitology》2011,49(1):95-98
Head louse infestation (HLI) is one of the most frequently occurring parasitic diseases in children. This study was conducted to investigate the socioeconomic and personal factors influencing HLI in the Republic of Korea. A total of 2,210 questionnaires about various factors related to HLI were obtained from children in 17 primary schools throughout the country. The rate of HLI was significantly lower in children who lived together with mother or in a family where both parents worked. In addition, HLI was lower in children whose fathers or mothers were public officers or teachers. However, HLI was higher in children who had small families and washed their hair less often. Education levels of parents and the number of children in family were not significant. Improvement of socioeconomic factors and personal hygiene will be helpful for reducing HLI. 相似文献
997.
998.
Lee J Kim SE Lee JY Kim SY Kang SU Seo SH Chun MW Kang T Choi SY Kim HO 《Bioorganic & medicinal chemistry letters》2003,13(6):1087-1092
A series of sulfamate surrogates of methionyl and isoleucyl adenylate have been investigated as MetRS and IleRS inhibitors by modifications of the sulfamate linker and adenine moieties. The discovery of 2-iodo Ile-NHSO(2)-AMP (58) as a potent Escherichia coli IleRS inhibitor revealed that a significant hydrophobic interaction between the 2-substituent of Ile-NHSO(2)-AMP and the adenine binding site of IleRS provided its high potency to the enzyme. 相似文献
999.
Here, we report the cloning and characterization of a common salivary gland-specific gene, Nf-1, from late instar Hydropsyche sp. larvae, and show that the corresponding gene product is translated in the gland and secreted to the gland lumen. The deduced Nf-1 protein is primarily composed of five repetitive sequence units of 63-65 amino acids, and contains a putative signal sequence composed of 19 amino acids. Secreted Nf-1 (approximately 37 kDa) was localized to the gland lumen by Western blotting of gland and lumen fractions. Together, the structure, expression pattern and protein localization of Nf-1 indicate that this protein is likely to be a major component of the silk shields and nets produced by the aquatic insect, Trichoptera. 相似文献
1000.
Synthesis and in vitro activity of new methylenepiperidinyl and methylenepyrrolidinyl oxazolidinone antibacterial agents 总被引:2,自引:0,他引:2
Kim HY Lee JS Cha JH Pae AN Cho YS Chang MH Koh HY 《Bioorganic & medicinal chemistry letters》2003,13(13):2227-2230
We have prepared and evaluated the antibacterial activities of a series of substituted methylenepiperidinyl and methylenepyrrolidinyl oxazolidinones against several gram-positive strains including the resistant strains of Staphyloccus and Enterococcus, such as MRSA, CRSA, MSSA and VRE. Some of them showed comparable or superior in vitro activities (MIC) to vancomycin. 相似文献