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排序方式: 共有509条查询结果,搜索用时 14 毫秒
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Antonio Hernandes Chaves Neto Karla Cristiana Queiroz Renato Milani Edgar Julian Paredes‐Gamero Giselle Zenker Justo Maikel P. Peppelenbosch Carmen Veríssima Ferreira 《Journal of cellular biochemistry》2011,112(1):71-77
Despite numerous reports on the ability of ascorbic acid and β‐glycerophosphate (AA/β‐GP) to induce osteoblast differentiation, little is known about the molecular mechanisms involved in this phenomenon. In this work, we used a peptide array containing specific consensus sequences (potential substrates) for protein kinases and traditional biochemical techniques to examine the signaling pathways modulated during AA/β‐GP‐induced osteoblast differentiation. The kinomic profile obtained after 7 days of treatment with AA/β‐GP identified 18 kinase substrates with significantly enhanced or reduced phosphorylation. Peptide substrates for Akt, PI3K, PKC, BCR, ABL, PRKG1, PAK1, PAK2, ERK1, ERBB2, and SYK showed a considerable reduction in phosphorylation, whereas enhanced phosphorylation was observed in substrates for CHKB, CHKA, PKA, FAK, ATM, PKA, and VEGFR‐1. These findings confirm the potential usefulness of peptide microarrays for identifying kinases known to be involved in bone development in vivo and in vitro and show that this technique can be used to investigate kinases whose function in osteoblastic differentiation is poorly understood. J. Cell. Biochem. 112: 71–77, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
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Bo Fernhall Linda M. Szymanski Patrick A. Gorman Jim Milani Donald C. Paup Craig M. Kessler 《European journal of applied physiology and occupational physiology》1998,78(3):247-252
In this study we investigated possible differences in fibrinolytic activity in cardiac patients while they performed treadmill
and cycle ergometry. Thirteen post-myocardial infarction patients completed two maximal exercise tests on treadmill and cycle
ergometers. Blood was collected before and after each exercise test and was analyzed for the fibrinolytic variables, tissue
plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) activity, and lactate. Maximal oxygen uptake, heart
rate, and ventilation were greater (P < 0.05) on the treadmill than during cycle ergometry, however, blood lactate was similar between modes. t-PA activity significantly
increased with exercise (P < 0.05) and there was a trend toward a reduction in PAI-1 activity with exercise, but this did not reach statistical significance.
The fibrinolytic responses to maximal exercise did not differ between the two modes of exercise studied. Therefore, exercise
intensity, but not the mode of exercise, appeared to be the primary determinant of the fibrinolytic response to acute exercise
in these patients.
Accepted: 29 January 1998 相似文献
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Zusammenfassung Es wurde mit Hilfe der kulturellen and der direkten Membranfilter-Methode ein Flussabschnitt der Fulda, der sich durch starke Abwasserführung auszeichnete, bakteriologisch untersucht. Bei der direkten mikroskopischen Zählung der Bakterien auf den Filtern wurden Zahlen gefunden, die die des Koch'schen Plattenverfahrens um das 10 bis 50-fache überstiegen. Das Studium der Bakterienformen in den verschiedenen filtrierten Proben läßt bei dem Vergleich mit den parallelen Untersuchungen - mit entsprechenden Vorbehalten — Schlüsse auf die Beziehungen zum Verschmutzungsgrad des Wassers zu.Herrn Prof. Dr. A. Thienemann zum 70. Geburtstag gewidmet. 相似文献
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Sequence variation in nuclear ribosomal small subunit,internal transcribed spacer and large subunit regions of Rhizophagus irregularis and Gigaspora margarita is high and isolate‐dependent 下载免费PDF全文
Odile Thiéry Martti Vasar Teele Jairus John Davison Christophe Roux Paula‐Ann Kivistik Andres Metspalu Lili Milani Ülle Saks Mari Moora Martin Zobel Maarja Öpik 《Molecular ecology》2016,25(12):2816-2832
Arbuscular mycorrhizal (AM) fungi are known to exhibit high intra‐organism genetic variation. However, information about intra‐ vs. interspecific variation among the genes commonly used in diversity surveys is limited. Here, the nuclear small subunit (SSU) rRNA gene, internal transcribed spacer (ITS) region and large subunit (LSU) rRNA gene portions were sequenced from 3 to 5 individual spores from each of two isolates of Rhizophagus irregularis and Gigaspora margarita. A total of 1482 Sanger sequences (0.5 Mb) from 239 clones were obtained, spanning ~4370 bp of the ribosomal operon when concatenated. Intrasporal and intra‐isolate sequence variation was high for all three regions even though variant numbers were not exhausted by sequencing 12–40 clones per isolate. Intra‐isolate nucleotide variation levels followed the expected order of ITS > LSU > SSU, but the values were strongly dependent on isolate identity. Single nucleotide polymorphism (SNP) densities over 4 SNP/kb in the ribosomal operon were detected in all four isolates. Automated operational taxonomic unit picking within the sequence set of known identity overestimated species richness with almost all cut‐off levels, markers and isolates. Average intraspecific sequence similarity values were 99%, 96% and 94% for amplicons in SSU, LSU and ITS, respectively. The suitability of the central part of the SSU as a marker for AM fungal community surveys was further supported by its level of nucleotide variation, which is similar to that of the ITS region; its alignability across the entire phylum; its appropriate length for next‐generation sequencing; and its ease of amplification in single‐step PCR. 相似文献
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An explosion set off in a limestone quarry located in the surroundings of Rapino (Chieti, central Italy), in the National Park of the Maiella Massif, exposed a small cave containing a Late Pleistocene fauna and Mousterian tools. Amongst the specimens is a fairly well preserved dorsal portion of a left mandibular corpus with associated M1 and M2 attributable to Macaca. The Grotta degli Orsi Volanti specimen is the very first macaque ever found in Abruzzo, but it also is one of the most recent, and the southern and easternmost known from Italy. 相似文献
100.
In the last decade the role of structural dynamics in controlling protein function was actively investigated using new and advanced experimental approaches. In particular, time resolved crystallography, despite some practical difficulties, is being used extensively to complement the study of protein structure-function relationships with information on the dynamics, based on experimental evidence. Here we present a short overview of the results obtained on dynamical properties of myoglobin and homologous hemoproteins, where the photosensitive heme-Fe--ligand bond has allowed transient intermediates to be studied by different flash photolysis methods coupled to Laue X-ray diffraction, thus highlighting some of the dynamical events that characterize diffusion of a diatomic ligand to/from the heme in model hemoproteins. 相似文献