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371.
Sergio Cardoso Laura Valverde Miguel A. Alfonso-Sánchez Leire Palencia-Madrid Xabier Elcoroaristizabal Jaime Algorta Susana Catarino David Arteta Rene J. Herrera María Teresa Zarrabeitia José A. Pe?a Marian M. de Pancorbo 《PloS one》2013,8(7)
The European genetic landscape has been shaped by several human migrations occurred since Paleolithic times. The accumulation of archaeological records and the concordance of different lines of genetic evidence during the last two decades have triggered an interesting debate concerning the role of ancient settlers from the Franco-Cantabrian region in the postglacial resettlement of Europe. Among the Franco-Cantabrian populations, Basques are regarded as one of the oldest and more intriguing human groups of Europe. Recent data on complete mitochondrial DNA genomes focused on macrohaplogroup R0 revealed that Basques harbor some autochthonous lineages, suggesting a genetic continuity since pre-Neolithic times. However, excluding haplogroup H, the most representative lineage of macrohaplogroup R0, the majority of maternal lineages of this area remains virtually unexplored, so that further refinement of the mtDNA phylogeny based on analyses at the highest level of resolution is crucial for a better understanding of the European prehistory. We thus explored the maternal ancestry of 548 autochthonous individuals from various Franco-Cantabrian populations and sequenced 76 mitogenomes of the most representative lineages. Interestingly, we identified three mtDNA haplogroups, U5b1f, J1c5c1 and V22, that proved to be representative of Franco-Cantabria, notably of the Basque population. The seclusion and diversity of these female genetic lineages support a local origin in the Franco-Cantabrian area during the Mesolithic of southwestern Europe, ∼10,000 years before present (YBP), with signals of expansions at ∼3,500 YBP. These findings provide robust evidence of a partial genetic continuity between contemporary autochthonous populations from the Franco-Cantabrian region, specifically the Basques, and Paleolithic/Mesolithic hunter-gatherer groups. Furthermore, our results raise the current proportion (≈15%) of the Franco-Cantabrian maternal gene pool with a putative pre-Neolithic origin to ≈35%, further supporting the notion of a predominant Paleolithic genetic substrate in extant European populations. 相似文献
372.
R H Ward B Modell M Petrou F Karag?zlu E Douratsos 《BMJ (Clinical research ed.)》1983,286(6377):1542-1544
Samples of chorionic villi were obtained in the first trimester by aspiration using a cannula passed transcervically under the guidance of real time ultrasound. In initial studies in 47 anaesthetised patients immediately before therapeutic abortion a method was developed giving a success rate of 89%. In 10 patients successful sampling was performed as an outpatient procedure without anaesthesia. In all, seven diagnostic procedures were undertaken and four of the five unaffected pregnancies continued. The technique of chorionic villous sampling using real time ultrasound is simple to learn and yields material for biochemical analysis and chromosomal study without the need for tissue culture. The exact obstetric risk, however, remains to be defined. 相似文献
373.
Within the past year, it has become apparent, in connection with its use on automatic flow cytometers, that the quality of commercially available Alcian Blue has significantly declined. A homologous series of alkylated (C1-C7) Astra Blue quaternary ammonium halides was prepared, characterized, and evaluated for the detection of basophils in whole blood. On the Technicon H6000 flow cytometer, the resolution of the basophil cluster from the main population of unstained white blood cells was found to depend on the chain length of the quaternizing alkyl group. Optimal basophil resolution was observed for the n-propyl derivative. Correlation of the new method vs Alcian Blue as the reference on the H6000 was expressed as follows: %Baso (Astra Blue) = 0.89% Baso (Alcian Blue) + 0.12% for 180 fresh whole blood samples. Within-run precision at a basophil differential count of 0.73% was characterized by SD = 0.11, identical to that obtained for Alcian Blue. Aqueous solutions of n-propyl Astra Blue iodide, in contrast to Alcian Blue, are thermally stable. Heating the reagent for 1 h at 100 degrees C did not alter solubility or cytochemical behavior. In contrast, parallel treatment of Alcian Blue yielded insoluble material by hydrolysis of the isothiouronium groups. The reagent for basophil detection comprises n-propyl Astra Blue iodide, lanthanum chloride, sodium chloride, Tween 20, and cetylpyridinium chloride. The Astra Blue derivatives were characterized by uv-vis, ir, percentage halide, paper chromatography, and 13C NMR. 相似文献
374.
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376.
Use of restriction endonucleases and exonuclease III to expose halogenated pyrimidines for immunochemical staining 总被引:1,自引:0,他引:1
We describe an enzymatic procedure for exposure of single-stranded DNA (ssDNA) containing the halogenated pyrimidines (HdUrd) bromodeoxyuridine (BrdUrd) or iododeoxyuridine (IdUrd) in single cells to antibodies that bind to HrdUrd only in ssDNA. Production of ssDNA was accomplished by digesting the DNA using either restriction endonucleases alone or endonucleases followed by exonuclease III. The enzymatic production of ssDNA was maximal when 0.1 N HCl or 0.1 M citric acid plus Triton X-100 was added to extract nuclear proteins prior to enzymatic denaturation. The restriction endonucleases Bam HI, Dde I, Eco RI, and Hind III produced significant ssDNA when used alone to allow binding of detectable amounts of the anti-HdUrd antibody IU-4 in Chinese hamster ovary cells labeled with 10 microM BrdUrd or 10 microM IdUrd. However, these treatments did not expose sufficient ssDNA to allow binding of IU-1, an anti-HdUrd antibody with lower binding affinity. IU-4 binding was most intense after treatment with Eco RI. Treatment with exonuclease III following endonuclease digestion allowed substantially more IU-4 binding. 相似文献
377.
378.
Summary The horseradish-peroxidase (HRP) technique was used to visualize the cell bodies of axons projecting to the goldfish pituitary. Following intravenous injections of HRP, HRP reaction products were observed in axons of the rostral pars distalis, proximal pars distalis, neurointermediate lobe, pituitary stalk and in axons coursing from the pituitary into the hypothalamus. HRP-labelled cells in the brain were localized in two regions only — the nucleus preopticus (NPO) pars magnocellularis and pars parvocellularis, and the nucleus lateralis tuberis (NLT) of the hypothalamus. These observations suggest that the NPO and NLT are the source of the neurosecretory innervation of the goldfish pituitary. 相似文献
379.
In the experiments on the anesthesized cats sodium hydroxybutyrate and piracetam, in contrast to glyo-6, have been shown to slow down the growth rate of creatine phosphokinase activity in the blood of the coronary sinus during 60-min occlusion of the coronary artery. At the same time, in the experiments on rats with 3-day myocardial infarction GABA derivatives like glyo-6 failed to influence the final size of cardiac necrosis. It may be concluded that anti-ischemic action of some drugs may be expressed only in the reduction of the rate of ischemic lesion development in the heart, but not in the limitation of the infarction size. 相似文献
380.