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1.
The formerly unknown microspheric form of Raadshoovenia salentina (Papetti and Tedeschi) and the new genus Cyclopseudedomia (type-species Cyclopseudedomia smouti n.g., n.sp.) are described from limestones of Campanian-Maastrichtian age from Gavrovo-Tripolitza zone in Greece. The new genus is distinguished from others of the sub-family RhapydionininaeKeijzer emend. Hamaoui and Fourcade by its almost entirely evolute test made of chambers tending to a cyclical stage (rapidly reached in the microspheric form).  相似文献   

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R-(-)-β-O-methylsynephrine (OMe-Syn) is an active compound isolated from a plant of the Rutaceae family. We conducted cell proliferation assays on various cell lines and found that OMe-Syn more strongly inhibited the growth of human umbilical vein endothelial cells (HUVECs) than that of other normal and cancer cell lines tested. In angiogenesis assays, it inhibited vascular endothelial growth factor (VEGF)-induced invasion and tube formation of HUVECs with no toxicity. The anti-angiogenic activity of OMe-Syn was also validated in vivo using the chorioallantonic membrane (CAM) assay in growing chick embryos. Expression of the growth factors VEGF, hepatocyte growth factor, and basic fibroblast growth factor was suppressed by OMe-Syn in a dose-dependent manner. Taken together, our results indicate that this compound could be a novel basis for a small molecule targeting angiogenesis.  相似文献   

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The trinuclear complex [L2Cu3(CF3CO2)4] (1) has been synthesized and its crystal structure determined. It consists of a linear arrangement of Cu(II) centers. The central copper atom is bonded to six oxygen atoms and has a tetragonally distorted octahedral geometry, while the terminal copper atoms are bonded to three oxygen and two nitrogen atoms and show a distorted square pyramidal geometry. The complex shows di-μ(O,O′) syn-syn carboxylate bridging as well as monoatomic (μ-O) bridging, along with phenolate (μ-O) oxygen bridging. Cryomagnetic investigations in the range 2-300 K revealed an antiferromagnetic spin exchange interaction with J = −95.7 cm−1, based on the isotropic exchange model Hex = −2J[S1 · S2 + S2 · S3].  相似文献   

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More than 90 remains of rhinoceroses bones and teeth have been recovered from the Layna Pliocene deposit. They correspond to a middle sized animal with stout bones and is quite different from both the large sized Pliocène D. megarhinus, the lower Villafranchian D. jeanvireti and the slim small Villafranchian D. etruscus. Its a new species belonging to the Dicerorhinus genus: D. miguelcrusafonti nov. sp. This species is also found in the Perpignan Pliocene formation, together with D. megarhinus.  相似文献   

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Simone Pouyet  Louis David 《Geobios》1979,12(6):763-817
Systematic revision of the genus Steginoporella: until now about eighty species were described. Only twenty recent species and thirty-four fossil ones are maintained. Several species and subspecies are new.The main interest of this revision is to establish a biostratigraphical scale: the settlement of this scale is based on the known stratigraphical distribution and on an attempt of phylogeny.The second advantage is ecological: all recent species live in marine tropical environment. The Steginoporella are good paleoecological indicators.At last, the establishment of a paleobiogeography, even incomplete and not definitive, allows to understand more easily recent distribution of Steginoporella connected with the great events of earth evolution.  相似文献   

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Nucleotide variation in chloroplast Asp(GUC)–Thr(GGU) intergenic region and genetic relationships among this group were examined among Elymus trachycaulus complex, Elymus alaskanus and Elymus caninus. The estimates of nucleotide diversity (π) ranged from 0.00111 for Elymus virescens to 0.03086 for E. caninus. Highest nucleotide diversity was found for E. caninus among the taxa analyzed here and followed by Elymus hyperarcticus. E. virescens accessions are genetically very uniform. Phylogenetic analysis suggested that E. caninus is paraphyletic. Elymus violaceus is genetically distinct from both E. alaskanus and E. trachycaulus. Our result indicates that Asp (GUC)–Thr (GGU) intergenic region has a high rate of evolutionary in Elymus species. Large indels detected in this region appear to have a highly rate of evolution and are thus more prone to homoplasy. We also first reported a minisatellite discovered in Asp (GUC)–Thr (GGU) region in Elymus species. The minisatellite identified here is an excellent candidate marker for studying population structures of Elymus species.  相似文献   

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Ten bacterial isolates belonging to the genus Vagococcus were obtained from Malian sour milk fènè produced from spontaneously fermented cow milk. However, these isolates could not be assigned to a species upon initial comparative 16S rRNA gene sequence analysis and were therefore further characterized. Rep-PCR fingerprinting of the isolates yielded four strain clusters represented by strains CG-21T (=DSM 21459T), 24CA, CM21 and 9H. Sequence identity of the 16S rRNA gene of DSM 21459T to its closest relative species Vagococcus penaei was 97.9%. Among the four rep strain clusters, DSM 21459T and 24CA shared highest 16S rRNA gene sequence identity of 99.6% while CM21 and 9H shared 98.6–98.8% with DSM 21459T and V. penaei CD276T. DSM 21459T and 24CA were thus subjected to a polyphasic typing approach. The genome of DSM 21459T featured a G + C content of 34.1 mol% for a 2.17-bp chromosome and a 15-kbp plasmid. Average nucleotide identity (ANI) of DSM 21459T to Vagococcus fluvialis bH819, V. penaei CD276T were 72.88%, 72.63%, respectively. DNA–DNA hybridization (DDH) similarities of strain DSM 21459T to other Vagococcus species were <42.0%. ANI and DDH findings strongly supported the 16S rRNA gene phylogenetic tree delineations. The fatty acid patterns of DSM 21459T was palmitic acid (C 16:0, 24.5%), oleic acid (C 18:1-ω9c, 32.8%), stearic acid (C 18:0, 18.9%). General physiological characterization of DSM 21459T and 24CA were consistent with those of the genus Vagococcus. Strain DSM 21459T and further strains are therefore considered to belong to a novel species, for which the nomenclature Vagococcus teuberi sp. nov. is proposed. The type strain is named CG-21T (=DSM 21459T and LMG 24695T).  相似文献   

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From the crystals of trans aquabis(N,N-dimethylglycinato-κNO)copper(II) dihydrate (compound 1, space group P212121) novel crystal structure of trans aquabis(N,N-dimethylglycinato-κNO)copper(II) (compound 2, space group Pbca) was obtained and analysed by X-ray diffraction. In the crystal structure 1, the O-H?O hydrogen bonds form three-dimensional network. In the crystal structure 2, two-dimensional layers stacking to each other are formed, with non-polar N,N-dimethyl groups placed on the opposite sides of the layers, and with the polar part in the middle forming CO?O-H and C-H?O hydrogen bonds. Different hydrogen bonding patterns in 1 and 2 do not pronouncedly affect molecular geometry of the title compound. Molecular mechanics force field suited for studying the properties of bis(amino acidato)copper(II) complexes in the solid state can follow the differences between the experimental molecular structures in the two diverse crystalline surroundings. To make possible direct comparison between crystal lattices, the force field was applied to predict unit cell packing of supposed anhydrous bis(N,N-dimethylglycinato)copper(II) in space group Pbca. Relative intermolecular energies of hypothetic anhydrous crystal and simulated 1 and 2 crystals are discussed. On the basis of experimental and theoretical results we conclude that the main effect of two water molecules of crystallisation in 1 is to stabilise the crystal packing via hydrogen bonding, whilst similar pyramidal copper(II) coordination geometry in 1 and 2 is due to axially coordinated water molecule and its intermolecular interactions.  相似文献   

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An isomer of leucocyanidin, (2R,3S,4R)-(+)-3,4,5,7,3′,4′-hexahydroxyflavan has been synthesized from (+)-taxifolin, isolated in its phe  相似文献   

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The unusual 18e seven-coordinate Mo(II) complex [Mo(NO)(H2NO-κ2N,O)(TpMe2)I] (1; [TpMe2] is hydrotris(3,5-dimethylpyrazol-1-yl)borate) has been synthesised and characterised by IR, 1H NMR and ESI-MS spectroscopies and by a single crystal X-ray diffraction study. The complex has a distorted pentagonal bipyramid structure with equatorial κ2-NH2O ligand (dN-O = 1.387 Å, dMo-N and dMo-O equal 2.049 and 2.092 Å, respectively). In the solid state 1 exists as a dimer (the point group Ci) due to the formation of two NH?O hydrogen bonds (dN-H?O = 2.064 Å) between the adjacent NH2O ligands, whilst in solution at/or above RT it resolves itself giving a monomer, which readily isomerises to more thermodynamically stable diastereoisomer.  相似文献   

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Saponification of the bis(carbamic acid ester) 1,3-C6H4(CMe2NHCO2Me)2 (1), made by the addition of methanol to commercial 1,3-C6H4(CMe2NCO)2, yielded the meta-phenylene-based bis(tertiary carbinamine) 1,3-C6H4(CMe2NH2)2 (2). Dinuclear [{(η4-1,5-C8H12)RhCl}2{μ-1,3-C6H4(CMe2NH2)2}] (3) resulted from the action of 2 on [{(η4-1,5-C8H12)Rh(μ-Cl)}2] in toluene. Combination of 2 with PdCl2 or K2[PdCl4] gave the dipalladium macrocycle trans,trans-[{μ-1,3-C6H4(CMe2NH2)2}2(PdCl2)2] (4) along with cyclometalated [{2,6-C6H3(CMe2NH2)2NC1N′}PdCl] (5). Substitution of PEt3 for the labile chlorido ligand of 5 afforded [{2,6-C6H3(CMe2NH2)2NC1, κN′}Pd(PEt3)]Cl (6). The crystal structures of the following compounds were determined: bis(carbamic acid ester) 1, ligand 2 as its bis(trifluoroacetate) salt [1,3-C6H4(CMe2NH3)2](O2CCF3)2, 2 · (HAcf)2, complexes 3 and 6, as well as 1,3-C6H4(CMe2OH)2 (the diol analogue of 2).  相似文献   

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Studies of skeleton elements of several jurassic species of Saitoum allow to compare them with Poulpus from Trias. The sub-family Poulpinae is introduced, caracterised by three cephalic arcs and the collar position of the cephalic structure. Among the jurassic forms, 4 species are newly described: S. corniculum, S. elegans, S. levium and S. trichylum.  相似文献   

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Two diatoms, Asterionella japonica (Cleve) and Chaetoceros lauderi (Ralfs), produced a similar lipidic antibiotic, whose activity increased after irradiation by visible light.In mixed cultures with the dinoflagellate Prorocentrum micans Ehrenberg, their cells contained higher amounts of the photoactivated antibiotic and a lower quantity of carotenoid pigments.These observations suggest the action of a chemical mediator released into the medium by P. micans, which inhibits the synthesis of pigments, thus leading to an increase of the photoactivation of the lipidic antibiotics in vivo. A similar inverse relationship between the concentration of carotenoids and the antibiotic activity was observed in several clones of Asterionella japonica isolated from different sea-water samples, and in cultures of the same diatom in the presence of diphenylamine. The importance of such phenomenon in a natural environment is discussed.  相似文献   

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Simon Tillier 《Geobios》1975,8(1):75-78
This miocene organism was described as an Alga (Lithophyllym vinassaiPATRINI, 1932 = Neosolenopora patriniiMASTRORILLI, 1955) and as a Bryozoan (Reptomulticava parviporosaCANU et LECOINTRE, 1934). This paper shows several salient features of Cyclostomatous Bryozoans (morphology, microstructure, zoarial brood chamber). The arguments for the classing of this organism among Algae are simultaneously refuted (pseudo-differentiation of the thallus, conceptacles).  相似文献   

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