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91.
92.
Here we study 109 Iberian roe deer individuals corresponding to 9 Spanish populations. Individuals were sampled at locations that are expected to have acted as refugia for the species during the 20th century. Samples were analyzed for a 436 bp mtDNA fragment from the HVI region of mitochondrial DNA and 10 microsatellites. The 109 sequences gave 31 different haplotypes that enabled identification of a new haplogroup (mainly present in Northwestern Iberian populations and representing roughly a third of our samples) that is not present in other European roe deer populations. Using microsatellites, correspondence analysis and molecular coancestry information revealed high molecular differentiation among Northwestern and Central-Southern Spain roe deer populations. Both sequence and microsatellite analysis reveal that the Spanish roe deer populations are genetically heterogeneous and have high genetic structure clearly separating the Pyrenean-reintroduced populations and two main areas for the species in Spain (Northwestern and Central-Southern) coinciding with the two main areas acting as refugia for the majority of the mammal species during glaciations. The implications of the obtained information as regards the phylogeography of the species are discussed together with suggestions as to appropriate strategies for the conservation and management of populations.  相似文献   
93.
94.
The antitumoral activity of a series of acetylated bis-tetrahydrofuranic acetogenins with a threo/trans/threo/trans/erythro relative configuration was characterized by four new natural and two semisynthetic, 15,24,30-trioxygenated acetogenins that were found to inhibit mitochondrial complex I enzyme as well as growth of several tumor cell lines. Placement of acetyl groups along the alkyl chain modulated the potency of the bis-tetrahydrofuranic acetogenins and could be important for future utilization of these compounds as chemotherapeutic agents.  相似文献   
95.
A method for the preparation of oligomers by linking chromophore units is described. Specifically, the synthesis of chromophore units having a protected-hydroxyl group and a phosphoramidite function is described, along with a method to link several units using solid-phase phosphite-triester protocols.  相似文献   
96.
The need to accelerate breeding for increased yield potential and better adaptation to drought and other abiotic stresses is an issue of increasing urgency. As the population continues to grow rapidly, the pressure on resources (mainly untouched land and water) is also increasing, and potential climate change poses further challenges. We discuss ways to improve the efficiency of crop breeding through a better physiological understanding by both conventional and molecular methods. Thus the review highlights the physiological basis of crop yield and its response to stresses, with special emphasis on drought. This is not just because physiology forms the basis of proper phenotyping, one of the pillars of breeding, but because a full understanding of physiology is also needed, for example, to design the traits targeted by molecular breeding approaches such as marker-assisted selection (MAS) or plant transformation or the way these traits are evaluated. Most of the information in this review deals with cereals, since they include the world's main crops, however, examples from other crops are also included. Topics covered by the review include the conceptual framework for identifying secondary traits associated with yield potential and stress adaptation, and how to measure these secondary traits in practice. The second part of the review deals with the real role of molecular breeding for complex traits from a physiological perspective. This part examines current developments in MAS and quantitative trait loci (QTL) detection as well as plant transformation. Emphasis is placed on the current limitations of these molecular approaches to improving stress adaptation and yield potential. The essay ends by presenting some ideas regarding future avenues for crop breeding given the current and possible future challenges, and on a multidisciplinary approach where physiological knowledge and proper phenotyping play a major role.  相似文献   
97.
Prodrugs are increasingly used as delivery vehicles for pharmaceutical agents that present solubility and/or pharmacokinetic/metabolic issues. In the course of the development of prodrugs for the antitumoral agent thiocoraline, standard coupling reagents and procedures failed to provide the desired target derivatives because of the lack of reactivity of its quinolinic alcohol. In contrast, the use of N,N,N',N'-tetramethylchloroformamidinium hexafluorophosphate (TCFH) resulted in good yields of ester prodrugs of thiocoraline and could be applicable to other drugs with similar limitations.  相似文献   
98.
The reaction of MoO2(mes)2 with S-H2BINOL (mes = 2,4,6-Me3C6H2; H2BINOL = 1,1′-bi-2-naphthol) and (CF3)2MeCOH in THF yielded the novel dioxo-molybdenum(VI) complexes MoO2(S-BINOL)(THF)2 and MoO2[OCMe(CF3)2]2(THF), respectively. Similar tungsten derivatives WO2(S-BINOL)(THF) and WO2[OCMe(CF3)2]2(THF) have been prepared by the reaction of WO2Cl2(DME) with the corresponding lithium salts of BINOL and 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, respectively. Catalytic experiments have shown that MoO2(S-BINOL)(THF)2 is an active catalyst in the sulfoxidation of methyl phenyl sulfide and in the epoxidation of cis-cyclooctene with tert-butylhydroperoxide, under mild conditions. The BINOL complex was, however, not found to be enantioselective. In addition, the catalytic activity of the molybdenum species MoO2(S-BINOL)(THF)2 and MoO2[OCMe(CF3)2]2(THF) in the hydrosilylation of carbonyl groups has been explored.  相似文献   
99.
A new copper(II) complex with chloride bridges and mixed blocking ligands, [{Cu(pzPh)(Opo)}2(μ-Cl)2] (1), whereby pzPh = 3-phenyl-pyrazolyl, and OpoH = 2-hydroxypyridine-N-oxide, has been obtained by degrading tris(pyrazolyl)borate in the presence of hydrated CuCl2 salt and the ligand Opo. The molecular structure of 1 was solved by X-ray diffraction. The two Cu(II) atoms of the dinuclear complex have a pyramidal arrangement in which the two pyramids share one base-to-apex edge with parallel basal planes. Magnetic susceptibility measurements revealed ferromagnetic coupling between the Cu atoms, with J = +8.72 cm−1. X-band EPR spectra of CH2Cl2 solutions of 1 were recorded at different temperatures.  相似文献   
100.
Chromosome territories constitute the most conspicuous feature of nuclear architecture, and they exhibit non-random distribution patterns in the interphase nucleus. We observed that in cell nuclei from humans with Down Syndrome two chromosomes 21 frequently localize proximal to one another and distant from the third chromosome. To systematically investigate whether the proximally positioned chromosomes were always the same in all cells, we developed an approach consisting of sequential FISH and CISH combined with laser-microdissection of chromosomes from the interphase nucleus and followed by subsequent chromosome identification by microsatellite allele genotyping. This approach identified proximally positioned chromosomes from cultured cells, and the analysis showed that the identity of the chromosomes proximally positioned varies. However, the data suggest that there may be a tendency of the same chromosomes to be positioned close to each other in the interphase nucleus of trisomic cells. The protocol described here represents a powerful new method for genome analysis.  相似文献   
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