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61.
Masaru Asari Kumiko Oka Tomohiro Omura Chikatoshi Maseda Yoshikazu Tasaki Hiroshi Shiono Kazuo Matsubara Mitsuyoshi Matsuda Keiko Shimizu 《Electrophoresis》2013,34(3):448-455
Amplification/hybridization‐based genetic analyses using primers containing locked nucleic acids (LNAs) present many benefits. Here, we developed a novel design for universal fluorescent PCR using LNAs. Universal fluorescent PCR generates intermediate nonlabeled fragments and final fluorescent fragments in a two‐step amplification process that uses locus‐specific primers with universal tails and universal fluorescent primers. In this study, a few standard nucleotides were replaced with LNAs only in the fluorescent universal primers. The sequence of the fluorescent universal primer significantly affected the amplification efficiency. For primers with three LNAs, the fluorescent primers with stable M13(‐47) sequences provided the most efficient signal (approximately tenfold higher than the primers with M13(‐21) sequences at lower Tm values). Moreover, AT‐rich LNA substitutions in the fluorescent primers produced much lower amplification efficiencies than GC‐rich substitutions. GC‐rich LNAs produced greater differences in Tm values among primers, and resulted in the preferential production of fluorescently labeled amplicons. The specificity and sensitivity of LNA‐containing fluorescent primers were assessed by genotyping eight STRs in Japanese individuals, and full STR profiles could be generated using as little as 0.25 ng of genomic DNA. The method permitted clear discrimination of alleles and represents sensitive STR genotyping at a reduced cost. 相似文献
62.
Farid R. Zaggout Hassan Abed Elazzez Abed El Fattah A. Qaraman Issa El Nahal 《Journal of Dispersion Science and Technology》2013,34(4):561-565
This study involves the behavior of universal indicator entrapped into the sol‐gel matrix. The encapsulation of universal indicator has been prepared by acid catalyzed sol‐gel reaction of tetraethylorthosilicate (TEOS) in the presence of universal indicator to produce transparent monolithic silica doping with universal indicator. The immobilized universal indicator pH‐indicator shows behavior similar to its solution counterpart. The UV/VIS spectra indicate that the universal indicator retains its structure during the sol‐gel reactions in terms of response to pH. The universal indicator can be regarded as uniformly distributed in the sol‐gel matrix. The use of SDS surfactant has positive effects on the immobilized universal indicator monolithic disk due to homogenizing the polymerizing system. This observation has been confirmed using polarized microscopy. 相似文献
63.
On doubling metric measure spaces endowed with a strongly local regular Dirichlet form, we show some characterisations of pointwise upper bounds of the heat kernel in terms of global scale-invariant inequalities that correspond respectively to the Nash inequality and to a Gagliardo–Nirenberg type inequality when the volume growth is polynomial. This yields a new proof and a generalisation of the well-known equivalence between classical heat kernel upper bounds and relative Faber–Krahn inequalities or localised Sobolev or Nash inequalities. We are able to treat more general pointwise estimates, where the heat kernel rate of decay is not necessarily governed by the volume growth. A crucial role is played by the finite propagation speed property for the associated wave equation, and our main result holds for an abstract semigroup of operators satisfying the Davies–Gaffney estimates. 相似文献
64.
For every , we present a set of points in the plane such that every planar 3-tree with n vertices has a straight-line embedding in the plane in which the vertices are mapped to a subset of . This is the first subquadratic upper bound on the cardinality of universal point sets for planar 3-trees, as well as for the class of 2-trees and serial parallel graphs. 相似文献
65.
Genotyping of exons 1 to 20 in Duchenne muscular dystrophy by universal multiplex PCR and short‐end capillary electrophoresis
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One rapid CE method was established to diagnose Duchenne muscular dystrophy (DMD). DMD is a severe recessive inherited disorder frequently caused by gene deletions. Among them, exons 1–20 account for nearly 30% of occurrences. In this study, the universal multiplex PCR was used to enhance the fluorescently labeling efficiency, which was performed only by one universal fluorescent primer. After PCR, a short‐end injection CE (short‐end CE) speeded up the genotyping of the DMD gene. This method involved no extra purification, and was completed within 9 min. The CE conditions contained a polymer solution of 1.5% hydroxylethylcellulose in 1× TBE buffer at 6 kV for separation. This method was applied to test six DMD patients and one healthy male person. The results showed good agreement with those of multiplex ligation‐dependent probe amplification. This method can be applied for clinical diagnosis of DMD disease. Accurate diagnosis of the DMD gene is the best way to prevent the disease. 相似文献
66.
Jolanta Pyteraf Witold Jamrz Mateusz Kurek Joanna Szafraniec-Szczsny Daniel Kramarczyk Karolina Jurkiewicz Justyna Knapik-Kowalczuk Jacek Tarasiuk Sebastian Wroski Marian Paluch Renata Jachowicz 《Molecules (Basel, Switzerland)》2021,26(11)
The flexibility of dose and dosage forms makes 3D printing a very interesting tool for personalized medicine, with fused deposition modeling being the most promising and intensively developed method. In our research, we analyzed how various types of disintegrants and drug loading in poly(vinyl alcohol)-based filaments affect their mechanical properties and printability. We also assessed the effect of drug dosage and tablet spatial structure on the dissolution profiles. Given that the development of a method that allows the production of dosage forms with different properties from a single drug-loaded filament is desirable, we developed a method of printing ketoprofen tablets with different dose and dissolution profiles from a single feedstock filament. We optimized the filament preparation by hot-melt extrusion and characterized them. Then, we printed single, bi-, and tri-layer tablets varying with dose, infill density, internal structure, and composition. We analyzed the reproducibility of a spatial structure, phase, and degree of molecular order of ketoprofen in the tablets, and the dissolution profiles. We have printed tablets with immediate- and sustained-release characteristics using one drug-loaded filament, which demonstrates that a single filament can serve as a versatile source for the manufacturing of tablets exhibiting various release characteristics. 相似文献
67.
We give a complete classification of Lagrangian immersions of homogeneous 3-manifolds (the Berger spheres, the Heisenberg group , the universal covering of the Lie group and the Lie group ) in 3-dimensional complex space forms. As a corollary, we get a new characterization of the Berger sphere in complex projective space. 相似文献
68.
The exact solutions to a class of differential equation are studied. Some special cases are discussed for the central potentials, single ring-shaped potential and the angular Teukolsky equation. A new expression to the associated Legendre polynomials is found. Some new properties of the universal associated-Legendre polynomials (UALPs) including the generating function, Rodrigues’ formula, parity, some special values and the recurrence relations are presented. A new different Rodrigues’ formula of associated Legendre polynomials is also obtained. 相似文献
69.
70.
Qingyi Cao Yahui Qian Handong Liang Zhanping Li Siyao Chen Liu Yang Qin Zhan 《Surface and interface analysis : SIA》2020,52(5):283-292
Pyrite is considered to be the major carrier of mercury in coal. Here, the chemical characteristics of two natural pyrite samples of different weathering degrees were characterized by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Thermal stability of Hg was also analyzed via temperature programmed desorption experiment (TPD). Characteristic ions such as S−, Fe+, FeS−, and FeS2− were detected on the surface of fresh pyrite. The release temperature of Hg ranged between 180°C and 300°C, and the characteristic peak of black HgS was recorded. In addition, abundant Fe2O3−, FeSO−, SO4−, and HSO4− were detected on the surface of weathered pyrite, and the release temperature of Hg therein was mainly distributed at 260°C to 380°C and 520°C to 600°C, corresponding to the characteristic peaks of red HgS and HgSO4, respectively. The results show that pyrite is acidified during weathering and that Hg forms in pyrite are transformed from the original state (HgS) to HgSO4. 相似文献