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1.
The plasmodial slime molds is the largest group in the phylum Amoebozoa. Its life cycle includes the plasmodial trophic stage and the spore‐bearing fruiting bodies. However, only a few species have their complete life cycle known in details so far. This study is the first reporting the morphogenesis of Didymium laxifilum and Physarum album. Spores, from field‐collected sporangia, were incubated into hanging drop cultures for viewing germination and axenic oat agar plates for viewing plasmodial development and sporulation. The spores of D. laxifilum and P. album germinated by method of V‐shape split and minute pore, respectively. The amoeboflagellates, released from spores, were observed in water film. The phaneroplasmodia of two species developed into a number of sporangia by subhypothallic type on oat agar culture. The main interspecific difference of morphogenesis was also discussed. 相似文献
2.
Pelagostrobilidium liui n. sp. (Ciliophora,Choreotrichida) from the Coastal Waters of Northeastern Taiwan and an Improved Description of Pelagostrobilidium minutum Liu et al., 2012 下载免费PDF全文
Po‐Cheng Chen Kuo‐Ping Chiang Sheng‐Fang Tsai 《The Journal of eukaryotic microbiology》2017,64(5):579-587
The number of somatic kineties in Pelagostrobilidium ranges from 4 to 6 according to the present state of knowledge. This study investigates Pelagostrobilidium liui n. sp. using live observation, protargol stain, and small subunit rDNA data sequencing. Pelagostrobilidium liui n. sp. is characterized by having a spherical‐shaped body, four somatic kineties, with kinety 2 spiraled around the left side of body, about six elongated external membranelles, and invariably no buccal membranelle. It differs from its most similar congener, Pelagostrobilidium minutum Liu et al., 2012 , in (i) cell shape; (ii) macronucleus width; (iii) oral apparatus; (iv) anterior orientation of kinety 2; (v) location where kinety 2 commences; (vi) arrangement of kinety 1; (vii) distance between the anterior cell end and the locations where kineties commence; and (viii) the presence of 12 different bases (including two deletions) in the small subunit rDNA sequences. The diagnosis of P. minutum Liu et al., 2012 is also improved to include the following new characteristics: invariably four somatic kineties; kineties 2 and 4 alone commence at the same level; kinety 2 originates from right anterior cell half on ventral side, extends sinistrally posteriorly, over kinety 1, around left posterior region, terminates near posterior cell end on dorsal side; kinety 1 commences below anterior third of kinety 2. 相似文献
3.
Selective method for identification and quantification of Bifidobacterium animalis subspecies lactis BB‐12 (BB‐12) from the gastrointestinal tract of healthy volunteers ingesting a combination probiotic of BB‐12 and Lactobacillus rhamnosus GG 下载免费PDF全文
4.
Talia Dan‐Cohen 《The journal of the Royal Anthropological Institute》2017,23(2):285-301
Distinctions between the ‘simple’ and the ‘complex’ have enjoyed a long and varied career in anthropology. Simplicity was once part of a collective fantasy about what life was like elsewhere, tingeing studies of tribal life with human longing for simpler ways of being. With the reflexive turn and the rise of cultural critique, simplicity has been all but excommunicated in favour of widespread diagnoses of complexity. In this article, I tease out some transformations in the uses of complexity in anthropology, and weave in some critical responses to these uses, spanning many decades, from within the discipline. I pay special attention to recent critiques by anthropologists who are beginning to grow weary of complexity as both an end‐in‐itself for scholarship and an empirical diagnosis. For these critics, complexity is deeply entwined with anthropological methods and knowledge practices. Drawing on these critical views, I suggest that complexity may be an epistemological artefact, rather than something that can be diagnosed ‘out there’, and offer a way of reframing complexity as a ‘dominant problematic’ in anthropology and beyond. 相似文献
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The Mycobacterium-Escherichia coli shuttle vector system, equipped with the pAL5000 replicon, is widely used for heterologous gene expression and gene delivery in mycobacteria. Despite its extensive use, this system has certain limitations, which has led to the development of alternative mycobacterial vector systems. The present study describes the molecular structure and expression profiles of a novel 18-kb linear plasmid, pMyong2, from Mycobacterium yongonense. Sixteen open reading frames and a putative origin of replication were identified, and the compatibility of the pMyong2 and pAL5000 vector systems was demonstrated. In recombinant Mycobacterium smegmatis (rSmeg), the pMyong2 vector system showed a copy number that was approximately 37 times greater than that of pAL5000. Furthermore, pMyong2 increased the mRNA and protein expression of the human macrophage migration inhibitory factor (hMIF) over pAL5000 levels by approximately 10-fold and 50-fold, respectively, demonstrating the potential utility of the pMyong2 vector system in heterologous gene expression in mycobacteria. Successful delivery of the EGFP gene into mammalian cells via rSmeg carrying the pMyong2 vector system was also observed, demonstrating the feasibility of this system for DNA delivery. In conclusion, the pMyong2 vector system could be effectively used not only for the in vivo delivery of recombinant protein and DNA but also for mycobacterial genetic studies as an alternative or a complement to the pAL5000 vector system. 相似文献
7.
Genome‐wide analysis identifies an african‐specific variant in SEMA4D associated with body mass index 下载免费PDF全文
Jie Zhou Lin Lei Amy R. Bentley Fasil Tekola-Ayele Sally N. Adebamowo Jennifer L. Baker Olufemi Fasanmade Godfrey Okafor Benjamin Eghan Jr. Kofi Agyenim‐Boateng Albert Amoah Clement Adebamowo Joseph Acheampong Thomas Johnson Johnnie Oli Daniel Shriner Adebowale A. Adeyemo Charles N. Rotimi 《Obesity (Silver Spring, Md.)》2017,25(4):794-800
8.
Solar Cells: Synergic Interface Optimization with Green Solvent Engineering in Mixed Perovskite Solar Cells (Adv. Energy Mater. 20/2017) 下载免费PDF全文
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10.
Hyuck Choi Byung-Chul Jeong Sung-Woong Hur Jung-Woo Kim Keun-Bae Lee Jeong-Tae Koh 《PloS one》2015,10(10)
Craniofacial bone defects are observed in a variety of clinical situations, and their reconstructions require coordinated coupling between angiogenesis and osteogenesis. In this study, we explored the effects of cartilage oligomeric matrix protein-angiopoietin 1 (COMP-Ang1), a synthetic and soluble variant of angiopoietin 1, on bone morphogenetic protein 2 (BMP2)-induced cranial bone regeneration, and recruitment and osteogenic differentiation of perivascular pericytes. A critical-size calvarial defect was created in the C57BL/6 mouse and COMP-Ang1 and/or BMP2 proteins were delivered into the defects with absorbable collagen sponges. After 3 weeks, bone regeneration was evaluated using micro-computed tomography and histologic examination. Pericyte recruitment into the defects was examined using immunofluorescence staining with anti-NG2 and anti-CD31 antibodies. In vitro recruitment and osteoblastic differentiation of pericyte cells were assessed with Boyden chamber assay, staining of calcified nodules, RT-PCR and Western blot analyses. Combined administration of COMP-Ang1 and BMP2 synergistically enhanced bone repair along with the increased population of CD31 (an endothelial cell marker) and NG2 (a specific marker of pericyte) positive cells. In vitro cultures of pericytes consistently showed that pericyte infiltration into the membrane pore of Boyden chamber was more enhanced by the combination treatment. In addition, the combination further increased the osteoblast-specific gene expression, including bone sialoprotein (BSP), osteocalcin (OCN) and osterix (OSX), phosphorylation of Smad/1/5/8, and mineralized nodule formation. COMP-Ang1 can enhance BMP2-induced cranial bone regeneration with increased pericyte recruitment. Combined delivery of the proteins might be a therapeutic strategy to repair cranial bone damage. 相似文献