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91.
VANJA BUGARSKI-STANOJEVIĆ JELENA BLAGOJEVIĆ GORANA STAMENKOVIĆ TANJA ADNAĐEVIĆ EVA B. GIAGIA-ATHANASOPOULOU MLADEN VUJOŠEVIĆ 《分类学与生物多样性》2013,11(1):95-106
The utility of the Inter Simple Sequence Repeat-Polymerase Chain Reaction (ISSR-PCR) was explored in order to determine genetic variation in six species of the genus Apodemus (A. flavicollis, A. sylvaticus, A. uralensis, A. agrarius, A. mystacinus and A. epimelas) at the individual level, population level, in separate geographic samples and in the species as a whole. Six optimized primers produced highly reproducible and polymorphic DNA markers with 98.3% polymorphic bands on a total sample of 91 individuals from 32 localities in Europe and Asia. Moreover, each primer allowed for an exact diagnosis of each of the six Apodemus species and thus provides a simple and reliable tool for the hitherto problematic discrimination of species from the subgenus Sylvaemus. Genetic distances between species ranged from 0.079, among the closely related A. flavicollis and A. sylvaticus, to 0.203 between A. mystacinus and A. agrarius. A. flavicollis, A. uralensis and A. sylvaticus display a strong population substructure. The range of genetic distances among geographic samples within last two species reaches the values obtained for closely related species. ISSR markers proved to be a simple and reliable tool for species diagnosis, as well as for estimating genetic diversity below the species level and for closely related species, but they showed questionable reliability for larger genetic distances. 相似文献
92.
Jovana J. Ajduković Evgenija A. Djurendić Edward T. Petri Olivera R. Klisurić Andjelka S. Ćelić Marija N. Sakač Dimitar S. Jakimov Katarina M. Penov Gaši 《Bioorganic & medicinal chemistry》2013,21(23):7257-7266
We report a rapid and efficient synthesis of A-ring modified 17α-picolyl and 17(E)-picolinylidene androstane derivatives from dehydroepiandrosterone. Compounds were validated spectroscopically and structurally characterized by X-ray crystallography. Virtual screening by molecular docking against clinical targets of steroidal anticancer drugs (ERα, AR, Aromatase and CYP17A1) suggests that 17(E)-picolinylidene, but not 17α-picolyl androstanes could specifically interact with CYP17A1 (17α-hydroxylase) with similar geometry and affinity as Abiraterone, a 17-pyridinyl androstane drug clinically used in the treatment of prostate cancer. In addition, several 17(E)-picolinylidene androstanes demonstrated selective antiproliferative activity against PC3 prostate cancer cells, which correlates with Abiraterone antiproliferative activity and predicted CYP17A1 binding affinities. Based on these preliminary results, 17(E)-picolinylidene androstane derivatives could be a promising starting point for the development of new compounds for the treatment of prostate cancer. 相似文献
93.
Donald G. Ćeskleba Steven AveLallemant Thomas F. Thuemler 《Environmental Biology of Fishes》1985,14(1):79-85
Synopsis Attempts to culture lake sturgeon, Acipenser fulvescens, in the past have generally met with limited success. The Wisconsin Department of Natural Resources has been experimenting
with artificial propagation of this species since 1979. The intent has been to develop egg collection and handling techniques,
hatching regimes, larva and juvenile diet formulations, and to evaluate juvenile survival after stocking. Eggs were collected
by caesarian section and fertilized with milt from ripe males taken during annual sturgeon spawning runs on the Fox and Wolf
rivers in central Wisconsin. After insemination, the eggs were treated in a saturated solution of Bentonite clay and transported
to the hatchery. Eggs were incubated at temperatures ranging from 13–16° C and embryos began hatching within 4 to 8 days.
Hatching success ranged from 42 to 96%. Yolksac absorption was complete within 10 days of hatching. Larvae then became positively
phototactic and swam actively as if searching for food. Successful larval diets consisted of live brine shrimp nauplii followed
by larger zooplankton, primarily Daphnia sp. Juveniles grew best on diets of live Tubifex sp. and chopped earthworms. Liver, fish mash (ground up trout) and pelleted dry food were poorly accepted. Hatchery reared
sturgeon grew more slowly than did wild fish. 相似文献
94.
IVAN J. SANSOM NEIL S. DAVIES MICHAEL I. COATES ROBERT S. NICOLL ALEX RITCHIE 《Palaeontology》2012,55(2):243-247
Abstract: Microvertebrate sampling of the Stairway Sandstone (Darriwilian, Middle Ordovician, central Australia) has yielded scales that are chondrichthyan‐like in their overall construction, and Tantalepis gatehousei gen. et sp. nov. is erected here to describe these specimens. Tantalepis gatehousei gen. et sp. nov. is the stratigraphically oldest microsquamous taxon described thus far, and the ‘shark‐like’ appearance of the scales may extend the chondrichthyan lineage back into the Middle Ordovician. The presence of ‘shark‐like’ scales in the fossil record some 50 myr prior to the first articulated chondrichthyan body fossils and 44 myr before the first clearly identifiable chondrichthyan teeth suggests there is a considerable scope for the recovery of articulated specimens with which to document the early history of crown gnathostomes. Traditional hypotheses of phylogenetic relationships among early jawed vertebrates were recently challenged by the proposal of a radically different tree topology. However, the development of a new data set specifically addressing scale‐based characters is required before taxa such as Tantalepis, that are based upon disarticulated remains alone, can be firmly placed within the emerging, revised, evolutionary narrative. 相似文献
95.
Wolfgang Willner Borja Jiménez‐Alfaro Emiliano Agrillo Idoia Biurrun Juan Antonio Campos Andraž Čarni Laura Casella János Csiky Renata Ćušterevska Yakiv P. Didukh Jörg Ewald Ute Jandt Florian Jansen Zygmunt Kącki Ali Kavgacı Jonathan Lenoir Aleksander Marinšek Viktor Onyshchenko John S. Rodwell Joop H.J. Schaminée Jozef Šibík Željko Škvorc Jens‐Christian Svenning Ioannis Tsiripidis Pavel Dan Turtureanu Rossen Tzonev Kiril Vassilev Roberto Venanzoni Thomas Wohlgemuth Milan Chytrý 《应用植被学》2017,20(3):494-512
96.
Lj. Tušek-Božić M. Ćurić J. Balzarini E. De Clercq 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):777-781
Abstract Diethyl and dibutyl α-anilinobenzylphosphonates and [α-(4-benzeneazoanilino)benzyl]-phosphonates and their new palladium(II) halide complexes were evaluated for their cytostatic and antiviral activity in different cell systems. 相似文献
97.
98.
ALEXEI A. OSKOLSKI EKATERINA L. KOTINA IVAN V. FOMICHEV FREDERIC TRONCHET PORTER P. LOWRY II 《Botanical journal of the Linnean Society. Linnean Society of London》2007,153(3):363-379
Wood anatomy was examined in 16 species of Meryta (a genus of c . 35 species) and bark anatomy was studied in 12 species. All but two of these taxa form an assemblage corresponding to the Northern Arc clade, one of two major groups identified by a recent molecular phylogenetic study. M. sinclairii and M. tenuifolia (corresponding to the New Zealand/Fiji clade) differ distinctly by having more numerous simple perforation plates, multiseriate rays with few marginal rows, and the absence of sclerified cells in collapsed secondary phloem, a bark feature that has not yet been found elsewhere in Araliaceae. The increase in abundance of simple perforation plates in the wood of these two species is not accompanied by a decrease in the number of bars on scalariform perforation plates. The wood structure of Meryta bears a strong resemblance to members of the Pacific Schefflera clade, sharing similar ranges of variation of several features. Bark characters, such as the diameter of the cortical secretory canals, the types of crystal in cortical cells, the types of axial parenchyma cell in collapsed secondary phloem, and the presence of sheath cells by phloem rays, appear to be of diagnostic value for some species of Meryta . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 363–379. 相似文献
99.
IVAN L. F. MAGALHÃES ADALBERTO J. SANTOS 《Zoological Journal of the Linnean Society》2012,166(1):14-53
The phylogenetic relationships amongst the New World spiny orb‐weaving spiders Micrathena and Chaetacis were assessed through parsimony and Bayesian analyses of morphological characters. A total of 146 characters was scored for ten outgroup taxa and 37 Micrathena and four Chaetacis species. The results indicate that Chaetacis nests within Micrathena and we propose Chaetacis as a junior synonym of Micrathena. Twelve subgeneric species groups of Micrathena are recognized and diagnosed. Species with extremely long spines evolved at least eight times in the genus and we suggest that this may be related to antipredator defences. Micrathena is primitively sexually monomorphic and extreme sexual size dimorphism has arisen at least six times in the genus. Most of these events are because of enlargement of the female in relation to the ancestral size, although in two cases sexual dimorphism was attained through male reduction, adding more data to the ‘giant females’ vs. ‘dwarf males’ controversy. The genus is probably of South American origin and has repeatedly invaded Central and North America. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 14–53. 相似文献