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51.
ColEl DNA replication is initiated by RNA II and inhibited by RNA I. Control of the replication occurs through the interaction between RNA I and RNA II. Therefore, RNases involved in the metabolism of RNA I and RNA II are expected to play a key role in the control of the ColEl plasmid replication. RNase H, RNase E, RNase III, RNase P, and polynucleotide phosphorylase carry out the many specific reactions of the RNA metabolism. 相似文献
52.
Jung Dong-Hyun Seo Dong-Ho Kim Ga-Young Nam Young-Do Song Eun-Ji Yoon Shawn Park Cheon-Seok 《Applied microbiology and biotechnology》2018,102(11):4927-4936
Applied Microbiology and Biotechnology - Resistant starch (RS) in the diet reaches the large intestine without degradation, where it is decomposed by the commensal microbiota. The fermentation of... 相似文献
53.
Abstract: Germination and growth of Pinus sylvestris L., Betula pendula Roth. and Quercus robur L. were investigated under laboratory conditions. Sterilized sand was used as the substrate and supplied with (a) increasing amounts of faeces of larvae of Dendrolimus pini L. which had been reared previously on Scotch pine and (b) a solution of NH4 NO3 of the same N-concentration as the faeces. The germination of pine and birch decreased strongly with increasing amounts of faeces, whereas the germination of oak was unaffected. When the inhibition of germination was overcome the further growth proceeded according to the species-specific growth pattern during a period of 200 days (oak) and 300 days, respectively (pine, birch). It was influenced neither by the supply of faeces nor of fertilizer. It is concluded from the results that the faeces of phytophagous insects contain inhibitory components which become effective only during the germination process of the species if there is a poor supply of nutrients in the seed (pine, birch). The subsequent stage of germ growth however, is not affected. The results are discussed in terms of a possible ecological function for insects as regulators of the species composition following mass propagations. 相似文献
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In this paper, three Korean species of the big‐head fly, genus Jassidophaga Aczél were treated: J. chiiensis (Ouchi), J. pala (Morakote) and J. villosa (Roser). Of these, J. pala is reported in Korea for the first time. A key to Korean species and photographs on external features are given. 相似文献
57.
HemoHIM, an herbal preparation of three edible herbs (Angelica gigas Nakai, Cnidium officinale Makino, Paeonia japonica Miyabe) is known to increase the Th1 immune response as well as reduce the allergic response in human mast cells. Here, our goal was to determine whether or not HemoHIM could induce Th1 cell differentiation as well as inhibit the development of airway inflammation. To study Th1/Th2 cell differentiation, naive CD4+ T cells isolated from C57BL/6 mouse spleens were cultured with or without HemoHIM. To examine airway inflammation, C57BL/6 mice were fed HemoHIM for 4 weeks before sensitization and provocation with ovalbumin (OVA). In an in vitro experiment, naive CD4+ T cells displayed increased Th1 (IFN-γ+ cell) as well as decreased Th2 (IL-4+ cell) differentiation in a HemoHIM concentration-dependent manner. Furthermore, in an airway inflammation mice model, eosinophil numbers in BALF, serum levels of OVA-specific IgE and IgG1, and cytokine (IL-4, IL-5, and IL-13) levels in BALF and the supernatant of splenocytes all decreased upon HemoHIM (100 mg/kg body weight) pretreatment (4 weeks). These results show that HemoHIM attenuated allergic airway inflammation in the mouse model through regulation of the Th1/Th2 balance. 相似文献
58.
Seongyup Kim Pil Young Jung Jin Suk Lee Soonjae Hwang Joon Hyung Sohn Yongdae Yoon Keum Seok Bae Young Woo Eom 《Cell biology international》2021,45(12):2443-2451
Skeletal muscle satellite cells (SkMSCs) play crucial roles in muscle fiber maintenance, repair, and remodeling; however, it remains unknown if these properties are preserved in cultured SkMSCs. In this study, we investigated the characteristics of cultured SkMSCs and their ability to regulate the activity of M1 macrophages. SkMSCs grew well with an average population doubling time of 26.26 ± 6.85 h during 10 passages (P). At P5, Pax7, MyoD, cluster of differentiation (CD)34, and CD56 were not expressed in SkMSCs, but the MSC markers CD73, CD105, and CD90 were expressed and the cells were differentiated into adipocytes and osteoblasts. When SkMSCs were cocultured with macrophages, interleukin (IL)-1β secretion was decreased, prostaglandin (PG)E2 was produced in coculture, and cyclooxygenase-2 protein was induced in an SkMSC-dependent manner. Hepatocyte growth factor (HGF) was highly secreted by monocultured SkMSCs; interferon-γ and lipopolysaccharide reduced its expression level. However, HGF expression recovered when SkMSCs and macrophages were cocultured. Although exogenous PGE2 upregulated macrophage pro-IL-1β expression, it suppressed the secretion of cleaved IL-1β. In contrast, HGF decreased active IL-1β secretion without affecting pro-IL-1β expression. Co-treatment of macrophages with HGF and PGE2 reduced pro-IL-1β expression level and active IL-1β secretion. Our results suggest that SkMSCs lose their satellite cell properties during serial passaging but acquire mesenchymal stem cell properties including the ability to exert an anti-inflammatory response for macrophages through PGE2 and HGF. 相似文献
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How different cultures evaluate a person? Is an important person in one culture is also important in the other culture? We address these questions via ranking of multilingual Wikipedia articles. With three ranking algorithms based on network structure of Wikipedia, we assign ranking to all articles in 9 multilingual editions of Wikipedia and investigate general ranking structure of PageRank, CheiRank and 2DRank. In particular, we focus on articles related to persons, identify top 30 persons for each rank among different editions and analyze distinctions of their distributions over activity fields such as politics, art, science, religion, sport for each edition. We find that local heroes are dominant but also global heroes exist and create an effective network representing entanglement of cultures. The Google matrix analysis of network of cultures shows signs of the Zipf law distribution. This approach allows to examine diversity and shared characteristics of knowledge organization between cultures. The developed computational, data driven approach highlights cultural interconnections in a new perspective.Dated: June 26, 2013 相似文献