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41.
Santiago Uribe-Lewis Rory Stark Thomas Carroll Mark J Dunning Martin Bachman Yoko Ito Lovorka Stojic Silvia Halim Sarah L Vowler Andy G Lynch Benjamin Delatte Eric J de Bony Laurence Colin Matthieu Defrance Felix Krueger Ana-Luisa Silva Rogier ten Hoopen Ashraf EK Ibrahim Fran?ois Fuks Adele Murrell 《Genome biology》2015,16(1)
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The validity of Gonatocerus Nees is discussed, and the identity of the type-species, G.longicornis, is established. Generic and specific synonymy is listed, and the neotype female of G.longicornis is redescribed. 相似文献
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Abstract. A new chalcidoid family, Rotoitidae fam.n., is described from New Zealand. The probable systematic affinities of Rotoitidae are discussed and the type genus and a single included species, Rotoita basalis gen. et sp.n., are described and illustrated. 相似文献
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CONSUELO SENDINO KAMIL ZÁGORŠEK PAUL D. TAYLOR 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):423-431
Sendino, C., Zágor?ek, K. & Taylor, P.D. 2012: Asymmetry in an Ordovician conulariid cnidarian. Lethaia, Vol. 45, pp. 423–431. Conulariids are fossils of the presumed polyps of an extinct scyphozoan cnidarian group. Their cone‐shaped skeletons normally show perfect tetraradial symmetry. However, in the Ordovician species Metaconularia anomala ( Barrande 1867 ) from Drabov (Czech Republic), tetraradial symmetry is compromised in three ways: (1) the skeleton often shows torsion; (2) the four sides may vary in width at the same level within one individual; and (3) one side may be deleted to give a triradial skeleton. Almost 2000 specimens were studied in museum collections. About 56% of analysed specimens are twisted in an anticlockwise direction (sinistral) when viewed from the apex towards the aperture, 28% show no torsion, 1% exhibit clockwise torsion (dextral) and the remaining 15% cannot be classified. Maximum measured torsion rate was 1.5°/mm. A significant negative correlation between torsion rate and length suggests that more highly torted individuals may have survived less well. Almost 5% of individuals show loss of one side for at least part of their lengths. Although many individuals have four sides of equal width, in a significant proportion the sides are of unequal width, up to a maximum/minimum side width ratio of 2 (i.e. widest face twice the width of the narrowest). In the absence of a satisfactory taphonomic model to explain the asymmetries, they are regarded as mirroring asymmetries in the living conulariids, with the strong preference for sinistral torsion interpreted as an example of a fixed asymmetry that was genetically controlled and heritable. It is speculated that the signalling protein Nodal as well as Hox‐like genes were involved in controlling the asymmetries described in M. anomala. 相似文献
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Summary. Forty AI bulls were tested for BoLA class I antigens by means of eight specific polyclonal reagents. By means of immobilization and sperm penetration tests these antigens were not detected on sperm cells. Isoimmunization studies with the use of sperm as antigenic stimuli and insemination of frozen spermatozoa diluted in specific reagents did not prove the presence of BoLA class I antigens on bovine spermatozoa. The cytotoxic tests used in this investigation were not reliable. 相似文献
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The number and concentration of haemopoietic stem cells in the femoral bone marrow and spleen of Wistar rats of different ages were investigated. Stem cells were assayed by the spleen colony technique in irradiated rat recipients. The ability of the recipient spleen to harvest transplanted tissue as a macroscopic colony was found to be dependent on the recipient's age. Changes with senescence were observed also in the concentration and the size of the stem cell compartment both in the marrow and spleen. No differences were demonstrated in the seeding of transplanted colony-forming units into the spleen of recipients of 1 and 4 months of age. A rats-mice strain difference in the effect of senescence on the haemopoietic stem cells is discussed. 相似文献
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Deniz EKİNCİ 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):1034-1039
The in vitro effects of the analgesic drugs, lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine, on the activity of purified human serum paraoxonase (hPON1) (EC 3.1.8.1.) were evaluated. hPON1 was purified from human serum with a final specific activity of 3840 U mg?1 and a purity of 25.3 % using simple chromatographic methods, including DEAE-Sephadex anion exchange and Sepharose 4B-L-tyrozine-1-napthylamine hydrophobic interaction chromatography. SDS-polyacrylamide gel electrophoresis indicated a single protein band corresponding to hPON1. The six analgesics dose-dependently decreased in vitro hPON1 activity, with IC50 values for lornoxicam, indomethacin, tenoxicam, diclofenac sodium, ketoprofen and lincomycine of 0.136, 0.195, 0.340, 1.639, 6.23 and 9.638 mM, respectively. Ki constants were 0.009, 0.097, 0.306, 0.805, 13.010 and 11.116 mM, respectively. Analgesics showed different inhibition mechanisms: lornoxicam, diclofenac sodium and lincomycine were uncompetitive, indomethacin and tenoxicam were competitive, ketoprofen was noncompetitive. According to the results, inhibition potency was lornoxicam>indomethacin>tenoxicam> diclofenac sodium>ketoprofen> lincomycine. 相似文献