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61.
The palynological investigation of the early Middle Miocene fluviolacustrine sedimentary rocks interfingering with volcanics of the Galatean Volcanic Province at Pelitçik Basin (Central Turkey) have yielded palynomorphs belonging to 51 spore and pollen taxa. The pollen record is dominated by Ulmus, Pinaceae, Quercus, Carpinus and Carya, and appears to reflect climatic conditions. Two pollen zones were established based on changing abundances of plant taxa. Zone 1 is characterized by dominance of Ulmus and Pinaceae. Zone 2 is differentiated and characterized by a dramatic increase in, and predominance of, Ulmus, Carya, deciduous Quercus, Carpinus, Salix and Pinaceae. Mixed mesophytic forests were widespread in the basin suggesting warm and temperate climate. The decreasing relative percentage of thermophilous taxa, with Engelhardia as the main component, and warm temperate taxa, such as Carya, at the upper part of Zone 2 generally indicates a climatic deterioration, probably related to the Middle Miocene cooling. 相似文献
62.
Critical role of OX40 in CD28 and CD154-independent rejection 总被引:20,自引:0,他引:20
Demirci G Amanullah F Kewalaramani R Yagita H Strom TB Sayegh MH Li XC 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(3):1691-1698
Blocking both CD28 and CD154 costimulatory pathways can induce transplant tolerance in some, but not all, transplant models. Under stringent conditions, however, this protocol often completely fails to block allograft rejection. The precise nature of such CD28/CD154 blockade-resistant rejection is largely unknown. In the present study we developed a new model in which both CD28 and CD154, two conventional T cell costimulatory molecules, are genetically knocked out (i.e., CD28/CD154 double-knockout (DKO) mice) and used this model to examine the role of novel costimulatory molecule-inducible costimulator (ICOS), OX40, 4-1BB, and CD27 in mediating CD28/CD154-independent rejection. We found that CD28/CD154 DKO mice vigorously rejected fully MHC-mismatched DBA/2 skin allografts (mean survival time, 12 days; n = 6) compared with the wild-type controls (mean survival time, 8 days; n = 7). OX40 costimulation is critically important in skin allograft rejection in this model, as blocking the OX40/OX40 ligand pathway, but not the ICOS/ICOS ligand, 4-1BB/4-1BBL, or CD27/CD70 pathway, markedly prolonged skin allograft survival in CD28/CD154 DKO mice. The critical role of OX40 costimulation in CD28/CD154-independent rejection is further confirmed in wild-type C57BL/6 mice, as blocking the OX40/OX40 ligand pathway in combination with CD28/CD154 blockade induced long term skin allograft survival (>100 days; n = 5). Our study revealed a key cellular mechanism of rejection and identified OX40 as a critical alternative costimulatory molecule in CD28/CD154-independent rejection. 相似文献
63.
Aras Aşcı Özlem Demirci Tunhan Albayrak İlknur Deveci Hikmet Göktürk Baydar Nilgün 《In vitro cellular & developmental biology. Plant》2022,58(6):1090-1098
In Vitro Cellular & Developmental Biology - Plant - Gentiana species belonging to the Gentianaceae family are medicinal plants rich in glycosides and phenolics. Gentiana lutea L. is a highly... 相似文献
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66.
A biofilm reactor not only shortens the lag phase of nisin production, but also enhances nisin production when combined with an appropriate pH profile. Due to the substrate inhibition that takes place at high levels of carbon source, fed-batch fermentation was proposed as a better alternative for nisin production. In this study, the combined effects of fed-batch fermentation and various pH profiles on nisin production in a biofilm reactor were evaluated. The tested pH profiles include 1) a constant pH profile at 6.8 (profile 1), 2) a constant pH profile with an autoacidification after 4 h (profile 2), and 3) a step-wise pH profile with pH adjustment every 2 h (profile 3). When profile 1 was applied, fed-batch fermentation enhanced nisin production for both suspended-cell (4,188 IU ml−1) and biofilm (4,314 IU ml−1) reactors, yielded 1.8- and 2.3-fold higher nisin titer than their respective batch fermentation. On the other hand, pH profiles that include periods of autoacidification (profiles 2 and 3) resulted in a significantly lower nisin production in fed-batch fermentation (2,494 and 1,861 IU ml−1 for biofilm reactor using profile 2 and 3, respectively) due to toxicity of excess lactic acid produced during the fermentation. Overall, this study suggested that fed-batch fermentation can be successfully used to enhance nisin production for both suspended-cell and biofilm reactors. 相似文献
67.
Ayşegül Doğan Selami Demirci Hüseyin Apdik Ezgi Avşar Apdik Fikrettin Şahin 《Tissue & cell》2017,49(6):711-718
Cancer as a multistep and complicated disease is regulated by several molecular and cellular events. Cancer treatment could be managed at the early stages when the tumor is confined in the tissue. However, disseminated cancer cells metastasize to other body parts and generate new tumors resulting in mortality. Mesenchymal stem cells (MSCs) are found in different body parts and helps adult tissue regeneration. The role of MSCs in cancer progression has emerged as one of the important aspects in cancer biology and is the aim of interest in recent years. In the current study, effects of Dental Pulp Stem Cells (DPSCs) on PC-3 prostate cancer cell proliferation and migration were conducted by cell proliferation, apoptosis, gene expression and cell migration analysis in vitro. Condition medium (CM) obtained from DPSCs increased cell proliferation of PC-3 cells and decreased apoptosis. Either administration of CM or trans well co-culture of DPSCs increased cell migration in scratch assay, confirmed by gene expression analysis of migratory genes including fibronectin, laminin and collagen type I (Col I). Furthermore, DPSCs participated in a self-organized structure with PC-3 cells in co-culture conditions. Overall, results indicated that DPSCs could promote PC-3 cancer cell proliferation and metastasis in co-culture conditions in vitro. 相似文献
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69.
Characterization of humic materials extracted from hazelnut husk and hazelnut husk amended soils 总被引:1,自引:0,他引:1
This study was carried out to determine effects of composted hazelnut husk (CHH) on some chemical properties of soil and soil
humic acid (HA). Compost application increases organic matter (OM) content of the soil considerably, OM value of 3.18% became
3.89% in 3 years time interval. Before application of compost, the soil pH was found to be 5.37, while after compost application
it became 5.61. FTIR characteristics of humic acid/humic acid-like materials extracted from the original hazelnut husk, composted
hazelnut husk and composted hazelnut husk amended soil have been investigated. C and O content of humic acid-like/humic acid
materials were in the range of 41.4–50.8% and 37.8–50.5%, respectively. The N content of the humic acid/humic acid-like materials are in the expected range for humic materials which is 2–6%.
Comparison of FTIR spectra of hazelnut husk and composted hazelnut husk humic acid-like fractions shows that both exhibit
similar but not identical series of IR bands indicating the presence of the same functional groups in both samples. The only
difference in the spectra seemed to be a decrement in the peak intensities of composted sample compared to uncomposted one.
The similar differentiation of the intensities of IR bands of compost applied soil sample has also been observed. The FTIR
spectral results show that the characteristics of composted material tend to become similar to that of soil humic acids characteristics
in time. 相似文献
70.
Demirci B Dadandi MY Paper DH Franz G Başer KH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):826-829
Phlomis linearis Boiss. & Bal. of the Lamiaceae family growing in central, east and southeast Anatolia is an endemic species for Turkey. The essential oil obtained from the aerial parts by hydro distillation was subsequently analyzed by GC/MS. The main components of the oil were found as beta-caryophyllene (24.2%), germacrene D (22.3%) and caryophyllene oxide (9.2%), among 49 identified compounds, representing 94.5% of the total essential oil. The overall biological activity of the essential oil (100 microg/pellet) was tested on the chorioallantoic membrane (CAM) of the fertilized hen's egg in order to examine the anti-angiogenic and anti-inflammatory activity. None of the tests showed pronounced activity, toxicity or irritation at the tested concentration. 相似文献