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21.
Nesibe Köse Ünal Akkemik H. Tuncay Güner H. Nüzhet Dalfes Henri D. Grissino-Mayer M. Sinan Özeren Tayfun Kındap 《International journal of biometeorology》2013,57(5):691-701
We developed a high quality reconstruction of May–June precipitation for the interior region of southwestern Turkey using regional tree-ring data calibrated with meteorological data from Burdur. In this study, three new climate sensitive black pine chronologies were built. In addition to new chronologies, four previously published black pine chronologies were used for the reconstruction. Two separate reconstructions were developed. The first reconstruction used all site chronologies over the common interval AD 1813–2004. The second reconstruction used four of the chronologies with a common interval AD 1692–2004. R 2 values of the reconstructions were 0.64 and 0.51 with RE values of 0.63 and 0.51, respectively. During the period AD 1692–1938, 41 dry and 48 wet events were found. Very dry years occurred in AD 1725, 1814, 1851, 1887, 1916, and 1923, while very wet years occurred in AD 1736, 1780, 1788, 1803, and 1892. The longest dry period was 16 years long between 1860 and 1875. We then explored relationships between the reconstructed rainfall patterns and major volcanic eruptions, and discovered that wetter than normal years occurred during or immediately after the years with the largest volcanic eruptions. 相似文献
22.
Ž. P. Marinšek N. Nolde I. Kardum‐Skelin R. Nizzoli B. Önal T. Rezanko E. Tani K. T. Ostović P. Vielh F. Schmitt G. Kocjan 《Cytopathology》2013,24(1):7-20
?. P. Marin?ek, N. Nolde, I. Kardum‐Skelin, R. Nizzoli, B. Önal, T. Rezanko, E. Tani, K. T. Ostovi?, P. Vielh, F. Schmitt and G. Kocjan Multinational study of oestrogen and progesterone receptor immunocytochemistry on breast carcinoma fine needle aspirates Objectives: To collect data on the variability of immunocytochemical (ICC) procedures used to detect oestrogen/progesterone receptors (ER/PR) on cytological material; to test the reproducibility of results; and to identify the crucial points in the ICC procedures that affect the result. Methods: Ten laboratories from eight countries participated in a two‐part study. In the first part, one of the participants (the coordinator) prepared and distributed cytospins from a fine needle aspirate of a primary breast carcinoma. Laboratories performed ICC staining for ER/PR according to their own methods on the test slides and in‐house positive controls. Slides were returned to the coordinator together with information on the preparation of positive control slides and the ICC methodology used. In the second part, obligatory methods of fixation and antigen retrieval were specified. Evaluation of results included grading the number of positive cells, staining intensity, background staining, cytoplasmic staining, sample condition and cellularity. Participants evaluated their own results, which were subsequently evaluated by the coordinator. Results: There was great variability in the preparation of slides for in‐house controls and ICC methodology. The outcome of ICC staining of in‐house control slides was excellent in two laboratories, adequate in three, sub‐optimal in four and inadequate in one. Only six obtained a positive reaction on the test slides and not all were of a high quality. Results of the second run were greatly improved in terms of cellularity of in‐house positive control slides, and scores for the percentage of stained cells and staining intensity of control and test slides. Cytospins and monolayer (ThinPrep®) preparations were superior to direct smears; methods of fixation and antigen retrieval were the key points in the staining process. Conclusions: Our experience points to the need for guidelines for hormonal receptor determination and external quality control on cytological material, in order for cytological methods to be used in routine clinical practice with a suitable degree of confidence. 相似文献
23.
Sibel Yılmaz Şerife Tokalıoğlu Serkan Şahan Ahmet Ülgen Ahmet Şahan Cengiz Soykan 《Journal of trace elements in medicine and biology》2013,27(2):85-90
An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was developed to determine trace zinc in water (tap, dam, and well water), biological (hair and nail), and liver samples. As a solid phase extractant, a synthesized new chelating resin, poly(2-thiozylmethacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propane sulfonic acid) was used. The resin was characterized by Fourier transform infrared spectroscopy, elemental analysis, and surface area by nitrogen sorption. A pre-concentration factor of 40-fold for a sample volume of 12.6 mL was obtained by using the time-based technique. The detection limit for the pre-concentration method was found to be 2.2 μg L?1. The precision (as RSD,%) for 10 replicate determinations at the 0.04 μg mL?1 Zn concentration was 1.2%. The calibration graph using the pre-concentration system for zinc was linear with a correlation coefficient of 0.998 in the concentration range from 0.005 to 0.05 μg mL?1. The applicability and accuracy of the developed method were estimated by the analysis spiked water, biological, liver samples (83–105%), and also certified reference material TMDA-70 (fortified lake water) and SPS-WW1 Batch 111-Wastewater. The results were in agreement with the certified values. 相似文献
24.
Özlem Biçen Ünlüer Arzu Ersöz Ridvan Say Özlem Tomsuk Hülya Sivas 《Biotechnology progress》2013,29(2):472-479
This study describes preparation and use of novel labeled and antibodious polymeric nanolabels (anti‐alpha fetoprotein cross‐linked nanolabels) as an immunogenic and semisynthetic nanolabel with potential prognostic and therapeutic roles for hepatoma cancer. Specificity, uptake, and binding efficiencies of the nanolabel have been examined in a human hepatosarcoma cell line HepG2, a human colorectal cell line DLD‐1, and a mouse myoblast cell line C2. Labeling of the cells has been performed by treating live and fixed cells with varying concentrations of the nanolabels and then, the cells have been examined under a fluorescence microscope. In addition, all cell lines have also been labeled using FITC‐conjugated nanotrastuzumab to compare the results obtained with those of the binding of the FITC‐nanoanti‐alpha fetoprotein nanolabels. Results show that FITC‐conjugated anti‐alpha fetoprotein cross‐linked nanolabels have been taken up by both live and fixed cells and have efficiently and specifically labeled HepG2 cells at a quite low concentration. Taken all together, the results indicate that the novel targeted nanoimaging tools and technique demonstrated their ability to detect the distribution of the nanolabels as probes in hepatoma cells. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 472–479, 2013 相似文献
25.
Martin Neumann Ebru Coskun Lars Fransecky Liliana H. Mochmann Isabelle Bartram Nasrin Farhadi Sartangi Sandra Heesch Nicola G?kbuget Stefan Schwartz Christian Brandts Cornelia Schlee Rainer Haas Ulrich Dührsen Martin Griesshammer Hartmut D?hner Gerhard Ehninger Thomas Burmeister Olga Blau Eckhard Thiel Dieter Hoelzer Wolf-Karsten Hofmann Claudia D. Baldus 《PloS one》2013,8(1)
Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has been identified as high-risk subgroup of acute T-lymphoblastic leukemia (T-ALL) with a high rate of FLT3-mutations in adults. To unravel the underlying pathomechanisms and the clinical course we assessed molecular alterations and clinical characteristics in a large cohort of ETP-ALL (n = 68) in comparison to non-ETP T-ALL adult patients. Interestingly, we found a high rate of FLT3-mutations in ETP-ALL samples (n = 24, 35%). Furthermore, FLT3 mutated ETP-ALL was characterized by a specific immunophenotype (CD2+/CD5-/CD13+/CD33-), a distinct gene expression pattern (aberrant expression of IGFBP7, WT1, GATA3) and mutational status (absence of NOTCH1 mutations and a low frequency, 21%, of clonal TCR rearrangements). The observed low GATA3 expression and high WT1 expression in combination with lack of NOTCH1 mutations and a low rate of TCR rearrangements point to a leukemic transformation at the pluripotent prothymocyte stage in FLT3 mutated ETP-ALL. The clinical outcome in ETP-ALL patients was poor, but encouraging in those patients with allogeneic stem cell transplantation (3-year OS: 74%). To further explore the efficacy of targeted therapies, we demonstrate that T-ALL cell lines transfected with FLT3 expression constructs were particularly sensitive to tyrosine kinase inhibitors. In conclusion, FLT3 mutated ETP-ALL defines a molecular distinct stem cell like leukemic subtype. These data warrant clinical studies with the implementation of FLT3 inhibitors in addition to early allogeneic stem cell transplantation for this high risk subgroup. 相似文献
26.
Anti‐HSV‐1 and HSV‐2 Flavonoids and a New Kaempferol Triglycoside from the Medicinal Plant Kalanchoe daigremontiana 下载免费PDF全文
Fernanda Gouvêa Gomes Ürményi Georgia do Nascimento Saraiva Livia Marques Casanova Amanda dos Santos Matos Luiza Maria de Magalhães Camargo Maria Teresa Villela Romanos Sônia Soares Costa 《化学与生物多样性》2016,13(12):1707-1714
Kalanchoe daigremontiana (Crassulaceae) is a medicinal plant native to Madagascar. The aim of this study was to investigate the flavonoid content of an aqueous leaf extract from K. daigremontiana (Kd), and assess its antiherpetic potential. The major flavonoid, kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 1 ), was isolated from the AcOEt fraction (Kd‐AC). The BuOH‐soluble fraction afforded quercetin 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside ( 2 ) and the new kaempferol 3‐O‐β‐d ‐xylopyranosyl‐(1 → 2)‐α‐l ‐rhamnopyranoside‐7‐O‐β‐d ‐glucopyranoside ( 3 ), named daigremontrioside. The crude extract, Kd‐AC fraction, flavonoids 1 and 2 were evaluated using acyclovir‐sensitive strains of HSV‐1 and HSV‐2. Kd‐AC was highly active against HSV‐1 (EC50 = 0.97 μg/ml, SI > 206.1) and HSV‐2 (EC50 = 0.72 μg/ml, SI > 277.7). Flavonoids 1 and 2 showed anti‐HSV‐1 (EC50 = 7.4 μg/ml; SI > 27 and EC50 = 5.8 μg/ml; SI > 8.6, respectively) and anti‐HSV‐2 (EC50 = 9.0 μg/ml; SI > 22.2 and EC50 = 36.2 μg/ml; SI > 5.5, respectively) activities, suggesting the contribution of additional substances to the antiviral activity. 相似文献
27.
We analysed migration strategies of the Osprey Pandion haliaetus on the poorly studied Eastern European–East African flyway. Four adult birds were equipped with GPS-based satellite-transmitters or data-loggers in their breeding sites in Estonia (north-eastern Europe) and tracked to their wintering grounds in Africa and back, during up to six migration cycles. Departure times, migration routes, as well as wintering and stopover sites varied remarkably between individuals but not much between years. Stopovers (2–30 days) were made mostly in Europe and less in the Middle East (Turkey) and north-eastern Africa (Egypt). The Ospreys did not avoid flying long distances over the sea, and the sea was crossed four times during the night. The current study adds to current knowledge on Osprey migration and should help to concentrate actions on protecting important flyways and stopover locations. 相似文献
28.
Enantioselective Ethylation of Various Aldehydes Catalyzed by Readily Accessible Chiral Diols 下载免费PDF全文
Four chiral C2‐symmetric diols were synthesized in a straightforward three‐step reaction and demonstrated excellent enantioselectivities and good overall yields. Their catalytic activities were examined via the addition of diethylzinc to various aldehydes. The enantioselective addition of diethylzinc to 2‐methoxybenzaldehyde gave the corresponding chiral secondary alcohol with high yields (up to 95%) and moderate to good enantiomeric excess (up to 88%). All synthesized ligands were evaluated in the addition of diethylzinc to various aldehydes in the presence of an additional metal such as Ti(IV) complexes. Chirality 28:593–598, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
29.
Gaëlle Lentini David J. Dubois Bohumil Maco Dominique Soldati‐Favre Karine Frnal 《Traffic (Copenhagen, Denmark)》2019,20(8):583-600
To efficiently enter host cells, apicomplexan parasites such as Toxoplasma gondii rely on an apical complex composed of tubulin‐based structures as well as two sets of secretory organelles named micronemes and rhoptries. The trafficking and docking of these organelles to the apical pole of the parasite is crucial for the discharge of their contents. Here, we describe two proteins typically associated with microtubules, Centrin 2 (CEN2) and Dynein Light Chain 8a (DLC8a), that are required for efficient host cell invasion. CEN2 localizes to four different compartments, and remarkably, conditional depletion of the protein occurs in stepwise manner, sequentially depleting the protein pools from each location. This phenomenon allowed us to discern the essential function of the apical pool of CEN2 for microneme secretion, motility, invasion and egress. DLC8a localizes to the conoid, and its depletion also perturbs microneme exocytosis in addition to the apical docking of the rhoptry organelles, causing a severe defect in host cell invasion. Phenotypic characterization of CEN2 and DLC8a indicates that while both proteins participate in microneme secretion, they likely act at different steps along the cascade of events leading to organelle exocytosis. 相似文献
30.
S. Ayla M. E. Okur M. Y. Günal E. M. Özdemir D. Çiçek Polat A. Yoltaş 《Biotechnic & histochemistry》2019,94(3):180-188
Laurocerasus officinalis Roem. (syn: Prunus laurocerasus L.) is a member of Rosaceae family. We investigated the antimicrobial and antioxidant activity of L. officinalis Roem in wound healing both in vivo and in vitro using an excisional wound model model in mice. We used four groups of eight mice as follows: untreated (control), empty gel, extract + gel (L. officinalis + gel), and Madecassol® groups. All treatments were applied topically once daily. The scar area, percentage wound closure and epithelization time were measured. L. officinalis promoted wound healing and increased granulation tissue, epidermal regeneration and angiogenesis. L. officinalis extract, which is known for its antioxidant and antimicrobial activities, may be useful for promoting wound healing. 相似文献