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1.
Bong Jin Kim Kyung Seob Song Hyun-Hee Kong Hee-Jae Cha Meesun Ock 《The Korean journal of parasitology》2014,52(1):85-87
We encountered a patient with heavy Hymenolepis nana infection. The patient was a 44-year-old Korean man who had suffered from chronic hepatitis (type B) for 15 years. A large number of H. nana adult worms were found during colonoscopy that was performed as a part of routine health screening. The parasites were scattered throughout the colon, as well as in the terminal ileum, although the patient was immunocompetent. Based on this study, colonoscopy may be helpful for diagnosis of asymptomatic H. nana infections. 相似文献
2.
Yu Song Xin Yao Yunhong Tan Yi Gan Junbo Yang Richard T. Corlett 《Tree Genetics & Genomes》2017,13(6):120
Phoebe is an economically important genus from the family Lauraceae. It is widely distributed in tropical and subtropical Asia, but systematics of the genus is unclear, and currently there is no species-level phylogeny. Here, we determined the complete chloroplast genome sequences of two species with long-range PCR and next genome sequencing technologies, and identified mutation sites and highly variable regions. These highly variable sites were used to reconstruct the phylogeny. The plastomes of Phoebe sheareri and P. omeiensis were 152, 876, and 152, 855 bp, respectively. Comparative genomic analysis indicated that there are 222 mutation sites including 146 substitutions, 73 indels, and 3 microinversions in both plastomes. Fifty-six single-nucleotide changes were identified in gene-coding regions, and 45 microsatellite sites were found for use in species identification. Fourteen divergence hotspots of 38 variable regions were located. Phylogeny was reconstructed using a Bayesian and maximum likelihood approach for 12 Phoebe species and other five related Lauraceae based on 15 of the highly variable regions including accD-psaI, atpB-rbcL, ndhC-trnV, ndhF-rpl32, petA-psbJ, psaA, psbA-trnH, rbcL, rps8-rpl14, rps16-trnQ, rpl32-trnL, trnC-petN, trnL-trnF, trnS-trnG, and ycf1 indicated that variability in the chloroplast regions proposed as variable is enough to detect divergence events among 12 taxa of Phoebe, and that maybe also useful to help to elucidate further relationships among other taxa of the genus. 相似文献
3.
David Dubbeldam Sofía Calero Donald E. Ellis Randall Q. Snurr 《Molecular simulation》2016,42(2):81-101
A new software package, RASPA, for simulating adsorption and diffusion of molecules in flexible nanoporous materials is presented. The code implements the latest state-of-the-art algorithms for molecular dynamics and Monte Carlo (MC) in various ensembles including symplectic/measure-preserving integrators, Ewald summation, configurational-bias MC, continuous fractional component MC, reactive MC and Baker's minimisation. We show example applications of RASPA in computing coexistence properties, adsorption isotherms for single and multiple components, self- and collective diffusivities, reaction systems and visualisation. The software is released under the GNU General Public License. 相似文献
4.
Dynamic changes of microtubule and actin structures in CV-1 cells during electrofusion 总被引:1,自引:0,他引:1
To study the involvement of the cytoskeletal system in the fusion of animal cells, we examined the dynamic changes of cytoskeletal proteins during the various stages of cell fusion. CV-1 cells were fused by applying a radio-frequency electrical pulse. Structural changes of microtubules (MTs) and F-actin were monitored simultaneously by double-label fluorescence microscopy. It was observed that in a few minutes after the initiation of cell fusion, MT bundles began to extend into the cytoplasmic bridges which were formed by fusing the membranes of neighboring cells. Later, a network of parallel MT bundles appeared between the adjacent nuclei of the fusing cells; such MT bundles may provide the mechanical links that are responsible for nuclear aggregation. The structural changes of F-actin during cell fusion were more complicated. We observed many different patterns of actin distribution in the fusing cells, including some giant, ring-shaped structures. Reorganization of actin is unlikely to be involved in the nuclear aggregation process. Instead, actin bundles condensed at the cell edges may help to widen the cytoplasmic bridges to allow merging of cellular contents between the fusing cells. 相似文献
5.
6.
Oily water treatment has attracted the attention of many researchers.The development of effective and cheap oil/water separation materials is urgent for treating this problem.Herein,inspired by superhydrophobic typical plant leaves such as lotus,red rose and marigold,superhydrophobic and superoleophilic copper mesh was fabricated by etching and then surface modification with 1-dodecanethiol (HS(CH2)11CH3).A rough silver layer is formed on the mesh surface after immersion.The obtained mesh surface exhibits superhydrophobicity and superoleophilicity and the static water contact angle was 153° ± 3°.In addition,the as-prepared copper mesh shows self-cleaning character with water and chemical stability.The as-prepared copper foam can easily remove the organic solvents either on water or underwater.We demonstrate that by using the as-prepared mesh,oils can be absorbed and separated,and that high separation efficiencies of larger than 92% are retained for various oils.Thus,such superhydrophobic and superoleophilic copper mesh is a very promising material for the application of oil spill cleanup and industrial oily wastewater treatment. 相似文献
7.
In Situ,Fast, High‐Temperature Synthesis of Nickel Nanoparticles in Reduced Graphene Oxide Matrix 下载免费PDF全文
Yiju Li Yanan Chen Anmin Nie Aijiang Lu Rohit Jiji Jacob Tingting Gao Jianwei Song Jiaqi Dai Jiayu Wan Glenn Pastel Michael R. Zachariah Reza Shahbazian Yassar Liangbing Hu 《Liver Transplantation》2017,7(11)
For the first time, a fast heating–cooling process is reported for the synthesis of carbon‐coated nickel (Ni) nanoparticles on a reduced graphene oxide (RGO) matrix (nano‐Ni@C/RGO) as a high‐performance H2O2 fuel catalyst. The Joule heating temperature can reach up to ≈2400 K and the heating time can be less than 0.1 s. Ni microparticles with an average diameter of 2 µm can be directly converted into nanoparticles with an average diameter of 75 nm. The Ni nanoparticles embedded in RGO are evaluated for electro‐oxidation performance as a H2O2 fuel in a direct peroxide–peroxide fuel cell, which exhibits an electro‐oxidation current density of 602 mA cm?2 at 0.2 V (vs Ag/AgCl), ≈150 times higher than the original Ni microparticles embedded in the RGO matrix (micro‐Ni/RGO). The high‐temperature, fast Joule heating process also leads to a 4–5 nm conformal carbon coating on the surface of the Ni nanoparticles, which anchors them to the RGO nanosheets and leads to an excellent catalytic stability. The newly developed nano‐Ni@C/RGO composites by Joule heating hold great promise for a range of emerging energy applications, including the advanced anode materials of fuel cells. 相似文献
8.
Low-level inversion of the L component of pseudorabies virus is not dependent on sequence homology. 下载免费PDF全文
G F Rall S Kupershmidt X Q Lu T C Mettenleiter T Ben-Porat 《Journal of virology》1991,65(12):7016-7019
Pseudorabies virus has a class 2 genome in which the S component is found in two orientations relative to the L component. The L component is bracketed by sequences that are partially homologous; it is found mainly in one orientation, but a small proportion is inverted (J. M. DeMarchi, Z. Lu, G. Rall, S. Kuperschmidt, and T. Ben-Porat, J. Virol. 64:4968-4977, 1990). We have ascertained the role of the patchy homologous sequences bracketing the L component in its inversion. A viral mutant, vYa, from which the sequences at the right end of the L component were deleted was constructed. Despite the absence of homologous sequences bracketing the L component in vYa, its L component inverted to an extent similar to that of the L component in the wild-type virus. These results show the following. (i) The low-frequency inversion of the L component of PrV is not mediated by homologous sequences bracketing this component. (ii) Cleavage of concatemeric DNA at the internal junction between the S and L components is responsible for the appearance of the minority of genomes with an inverted L component in populations of pseudorabies virus. (iii) The signals present near or at the end of the S component are sufficient to allow low-frequency cleavage of concatemeric DNA; the sequences at the end of the L component are not essential for cleavage, although they enhance it considerably. 相似文献
9.
10.
Changes in nitrogen resorption traits of six temperate grassland species along a multi-level N addition gradient 总被引:1,自引:0,他引:1
Ju-Ying Huang Xiao-Guang Zhu Zhi-You Yuan Shi-Huan Song Xin Li Ling-Hao Li 《Plant and Soil》2008,306(1-2):149-158
Nitrogen (N) resorption from senescing leaves is an important mechanism of N conservation for terrestrial plant species, but
changes in N-resorption traits over wide-range and multi-level N addition gradients have not been well characterized. Here,
a 3-year N addition experiment was conducted to determine the effects of N addition on N resorption of six temperate grassland
species belonging to three different life-forms: Stipa krylovii Roshev. (grass), Cleistogenes squarrosa (T.) Keng (grass), Artemisia frigida Willd. (semishrub), Melissitus ruthenica C.W.Wang (semishrub and N-fixer), Potentilla acaulis L. (forb) and Allium bidentatum Fisch.ex Prokh. (forb). Generally, N concentrations in green leaves increased asymptotically for all species. N concentrations
in senescent leaves for most species (5/6) also increased asymptotically, except that the N concentration in senescent leaves
of A. bidentatum was independent of N addition. N-resorption efficiency decreased with increasing N addition level only for S. krylovii and A. frigida, while no clear responses were found for other species. These results suggest that long-term N fertilization increased N
uptake and decreased N-resorption proficiency, but the effects on N-resorption efficiency were species-specific for different
temperate grassland species in northern China. These inter-specific differences in N resorption may influence the positive
feedback between species dominance and N availability and thus soil N cycling in the grassland ecosystem in this region. 相似文献