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91.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30?kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected. 相似文献
92.
Kathryn E. Keenan Lampros C. Kourtis Thor F. Besier Derek P. Lindsey Garry E. Gold Scott L. Delp 《Computer methods in biomechanics and biomedical engineering》2013,16(4):415-422
Cartilage material properties are important for understanding joint function and diseases, but can be challenging to obtain. Three biphasic material properties (aggregate modulus, Poisson's ratio and permeability) can be determined using an analytical or finite element model combined with optimisation to find the material properties values that best reproduce an experimental creep curve. The purpose of this study was to develop an easy-to-use resource to determine biphasic cartilage material properties. A Cartilage Interpolant Response Surface was generated from interpolation of finite element simulations of creep indentation tests. Creep indentation tests were performed on five sites across a tibial plateau. A least-squares residual search of the Cartilage Interpolant Response Surface resulted in a best-fit curve for each experimental condition with corresponding material properties. These sites provided a representative range of aggregate moduli (0.48–1.58 MPa), Poisson's ratio (0.00–0.05) and permeability (1.7 × 10? 15–5.4 × 10? 15 m4/N s) values found in human cartilage. The resource is freely available from https://simtk.org/home/va-squish. 相似文献
93.
Abstract A convenient, high-yield synthesis of 1,3,5-tri-O-acetyl-2-deoxy-α. β-D-erythro-pentofuranose from 2-deoxy-D-erythro-pentose is described. 相似文献
94.
Christopher I Keeling Macaire MS Yuen Nancy Y Liao T Roderick Docking Simon K Chan Greg A Taylor Diana L Palmquist Shaun D Jackman Anh Nguyen Maria Li Hannah Henderson Jasmine K Janes Yongjun Zhao Pawan Pandoh Richard Moore Felix AH Sperling Dezene P W Huber Inanc Birol Steven JM Jones Joerg Bohlmann 《Genome biology》2013,14(3):R27
95.
96.
Gerald L. Gold 《Ethnos》2013,78(1-2):60-81
The Zhi Mä Funeral Ceremony of the Na‐Khi of Southwest China. Joseph F. Rock. Studia Instituti Anthropos, Vol. 9. St. Gabriel's Mission Press, Vienna‐Mödling, 1955. 228 pp., 10 pls. Mythen und Mysterien. Magie und Religian der Tibeter. M. Hermanns. Verlag Balduin Pick, Köln, 1956. 400 pp., 49 figs., 1 map. Oracles and Demons of Tibet. René de Nebesky‐Wojkowitz. Mouton &; Co., ‘s‐Gravenhage, 1956. 666 pp., 10 pls., 25 figs. Die Lamaistische Kunst in der Umwelt von Tibet. Siegbert Hummel. Otto Harrassowitz, Leipzig, 1955. 149 pp., 134 figs., 1 map. El Monte. Igbo Finda, Ewe Orisha, Vititinfinda. Notas sobre la religión, la magía, las supersticiones y el folklore de los negros criollos y del pueblo de Cuba. Lydia Cabrera. Ediciones C. R., Habana 1954. 564 pp., 25 pls. Die Hieroglyphen der Maya‐Handschriften. Günter Zimmermann. Universität Hamburg, Abhandlungen aus dem Gebiet der Auslandskunde, Band 62, Reihe B: Völkerkunde, Kulturgeschichte und Sprachen, Band 34. Verlag Cram, de Gruyter &; Co., Hamburg, 1956. 174 pp., 8 pls., ca. 2000 text ill. Das Indianerbuch. Geb. F. A. Brockhaus Verlag. Leipzig 1956. Eva Lips. 443 PP., 32 pls., 11 text ill., 6 maps. Cloth bound DM 10.80. Das doppelte Geschlecht. Ethnologische Studien zur Bisexualität in Ritus und Mythos. Hermann Baumann. Berlin 1955. 420 pp., 5 maps. Von Fremden Völkern und Kulturen. Beiträge zur Völkerkunde. Hans Plischke zum 65. Geburtstage gewidmet von seinen Kollegen und Freunden, Schülern und Mitarbeitern. Herausgegeben von W. Lang, W. Nippold und G. Spannaus. Droste‐Verlag, Düsseldorf, 1955. 284 pp., 30 figs., 2 maps. Die Wiener Schule der Völkerkunde — The Vienna School of Ethnology. Festschrift anlässlich des 25‐jährigen Bestandes des Institutes für Völkerkunde der Universität Wien (1929–1954). Herausgeber J. Haekel, A. Hohenwart‐Gerlachstein und A. Slawik, Wien 1956. VIII+ 568 S., 11 Taf., 21 Textill, und 2 Karten. $ 8.60. Das Problem des Völkertodes. Eine Studie zur historischen Bevölkerungsbiologie. Ilse Schwidetzky. Ferdinand Enke Verlag, Stuttgart 1954. 165 pp. This and the following review have been held over from former times, when these contributions were apt to prove rather exhaustive. Reviews are now heavily cut down irrespective of the significance of the work presented. 相似文献
97.
Hyosung Lee Alexander S. Gold Xiao-Fang Yang Rajesh Khanna Harold Kohn 《Bioorganic & medicinal chemistry》2013,21(24):7655-7662
Several antiepileptic drugs exert their activities by inhibiting Na+ currents. Recent studies demonstrated that compounds containing a biaryl-linked motif (Ar-X-Ar′) modulate Na+ currents. We, and others, have reported that compounds with an embedded benzyloxyphenyl unit (ArOCH2Ar′, OCH2 = X) exhibit potent anticonvulsant activities. Here, we show that benzyloxybenzylammonium chlorides (+H3NCH2C6H4OCH2Ar′ Cl?) displayed notable activities in animal seizure models. Electrophysiological studies of 4-(2′-trifluoromethoxybenzyloxy)benzylammonium chloride (9) using embryonic cortical neurons demonstrated that 9 promoted both fast and slow inactivation of Na+ channels. These findings suggest that the potent anticonvulsant activities of the earlier compounds were due, in part, to the benzyloxyphenyl motif and provide support for the use of the biaryl-linked pharmacophore in future drug design efforts. 相似文献
98.
99.
The molecular integrity of the active site of phytases from fungi is critical for maintaining phytase function as efficient catalytic
machines. In this study, the molecular dynamics (MD) of two monomers of phytase B from Aspergillus niger, the disulfide intact
monomer (NAP) and a monomer with broken disulfide bonds (RAP), were simulated to explore the conformational basis of the
loss of catalytic activity when disulfide bonds are broken. The simulations indicated that the overall secondary and tertiary
structures of the two monomers were nearly identical but differed in some crucial secondary–structural elements in the vicinity of
the disulfide bonds and catalytic site. Disulfide bonds stabilize the β-sheet that contains residue Arg66 of the active site and
destabilize the α-helix that contains the catalytic residue Asp319. This stabilization and destabilization lead to changes in the shape
of the active–site pocket. Functionally important hydrogen bonds and atomic fluctuations in the catalytic pocket change during the
RAP simulation. None of the disulfide bonds are in or near the catalytic pocket but are most likely essential for maintaining the
native conformation of the catalytic site.
Abbreviations
PhyB - 2.5 pH acid phophatese from Aspergillus niger, NAP - disulphide intact monomer of Phytase B, RAP - disulphide reduced monomer of Phytase B, Rg - radius of gyration, RMSD - root mean square deviation, MD - molecular dynamics. 相似文献100.
The study of stem cells in cnidarians has a history spanning hundreds of years, but it has primarily focused on the hydrozoan genus Hydra. While Hydra has a number of self-renewing cell types that act much like stem cells—in particular the interstitial cell line—finding cellular homologues outside of the Hydrozoa has been complicated by the morphological simplicity of stem cells and inconclusive gene expression data. In non-hydrozoan cnidarians, an enigmatic cell type known as the amoebocyte might play a similar role to interstitial cells, but there is little evidence that I-cells and amoebocytes are homologous. Instead, self-renewal and transdifferentiation of epithelial cells was probably more important to ancestral cnidarian development than any undifferentiated cell lineage, and only later in evolution did one or more cell types come under the regulation of a “stem” cell line. Ultimately, this hypothesis and competing ones will need to be tested by expanding genetic and developmental studies on a variety of cnidarian model systems. 相似文献