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OBJECTIVE: Preoperative cytologic diagnoses of ocular surface squamous neoplasms were evaluated and compared with histologic diagnoses. STUDY DESIGN: Impression cytology (Millipore filter paper) and brush cytology were applied to 32 patients who had conjunctival neoplasms. Papanicolaou-stained cytologic preparations and hematoxylin and eosin-stained histologic sections were examined by light microscopy. RESULTS: The brush technique was used on 27 patients; impression cytology was applied in 5 cases. Cytologic and histologic diagnoses were concordant in 26 cases. Squamous cell carcinoma or carcinoma in situ was diagnosed in 18 and dysplasia in 4 cases. Squamous metaplasia and normal-appearing conjunctival epithelial cells were diagnosed cytologically in four cases; of those histologic diagnoses, one was pterygium and three, conjunctival nevus. Four cases revealed discrepancies between the cytologic and histologic preparations. There was one false positive result, and one case was subconjunctival invasion of basal cell carcinoma of the eyelid. CONCLUSION: Impression and brush cytology are fast, cost-effective, reliable and noninvasive diagnostic tools for ocular surface squamous neoplasms. However, the brush technique has several advantages over impression cytology. 相似文献
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Ümmühan İşoğlu-Alkaç Canan Başar-Eroğlu Ahmet Ademoğlu Tamer Demiralp Michael Miener Michael Stadler 《Biological cybernetics》1998,79(5):437-442
In previous studies, a perceptual switching related potential was obtained during the observation of a multistable dynamic
reversal pattern, where the averaging of the single responses was triggered by subjects pressing a button. The present methodological
study aims to increase the signal quality of perceptual switching related potentials considering the dependence of the measurement
method on the reaction time of the subject, which may vary significantly during a session, leading to low-amplitude waveform
in the averaged event-related-potential (ERP). To overcome this problem in measuring the electrophysiological correlate of
an internal event, a pattern selection method based on the wavelet transform (WT) is proposed to choose a subset of single
ERPs with more homogenous latencies. Nine subjects observed a Necker cube and were instructed to press the button immediately
after perceptual switching. A slow, low-amplitude positive wave with frontocentral amplitude maxima was observed around 250 ms
prior to the button press. After the application of a 5 octave WT on single sweeps, the time-frequency coefficients obtained
in each octave were averaged across trials. The most dominant feature representing the averaged ERP was the delta (0.5–4 Hz)
coefficient occurring between 250 and 125 ms before the button press. By averaging the subset of the single sweeps containing
this property, a sharpening and significant amplitude increase of the response peak was observed.
Received: 12 September 1997 / Accepted in revised form: 9 July 1998 相似文献
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Nuray Bogurcu Canan Sevimli-Gur Besra Ozmen Erdal Bedir Kemal Sami Korkmaz 《Biochemical and biophysical research communications》2011,(4):738
Endemic Alkanna cappadocica was used to isolate novel antitumor molecules from Turkish landscapes in our previous studies. In this study, deoxyalkannin (ALCAP1), β,β-dimethylacrylalkannin (ALCAP2), acetylalkannin (ALCAP3), and alkannin (ALCAP4) as well as the novel isolated compounds 5-methoxydeoxyalkannin (ALCAP5), 8-methoxydeoxyalkannin (ALCAP6), 5-methoxyacetylalkannin (ALCAP7), 5-methoxy-β,β-dimethylacrylalkannin (ALCAP8) were characterized. The topoisomerase I (topo I) inhibitory activity of ALCAPs was investigated using in vitro plasmid relaxation assay and found that ALCAP2, 3, 4 and 7 were potent inhibitors at 2–6 μM concentrations. Further, DNA damage response to ALCAP treatments was also studied by measuring the H2AX(S139) and ATM(S1981) phosphorylations. ALCAP2, 7 and 8 induced the DNA damage and apoptosis, consistently resulted in PARP cleavage at nanomolar concentrations in K562 leukemia cells. Moreover, when the free radical (ROS) generating capacity of the compounds was studied by 2′,7′-dichlorofluorescein-diacetate assay using flow cytometry, we found that a known antioxidant N-acetyl-cysteine almost completely abrogated the H2AX(S139) phosphorylations and the caspase 3 cleavage and activation. Thus, γH2AX(S139) foci formation remained higher than the control, and an increase in CHK2(T68) phosphorylation was observed by ALCAP2 and 7 treatments suggested that, these compounds can be potential therapeutics against tumor cell growth because of their unique DNA damaging abilities additional to enzyme inhibition similar to those of doxorubicin. 相似文献
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Canan Uluoglu Ugur Hodoglugil H. Zafer Gü ney C. Zafer G rgü n Nurettin Abacioglu Hakan Zengil 《Biological Rhythm Research》1998,29(4):343-352
The presence of temporal patterns in the responses of vascular smooth muscle to relaxing agents have been known. The aim of this study was to examine the variations in the in vitro sensitivity of rat aorta to papaverine and theophylline in both endothelium-intact and -denuded rings. The animals were synchronized with a 12-h light: 12-h dark schedule. Rat thoracic aorta rings were obtained from animals sacrificed at six different times (09:00, 13:00, 17:00, 21:00, 01:00 and 05:00) of the day. Tissues were precontracted submaximally with phenylephrine and then were relaxed by papaverine (10-8 - 10-4 M) and theophylline (10-7 &miknus; 10-3 M) applied cumulatively. The responses to most of the concentrations and EC50 values for papaverine demonstrated an ultradian rhythm with an 8 h periodicity. Time-dependent variations were not found in the responses to theophylline. The results are discussed in relation with the time-dependent differences in signal transducing mechanisms. 相似文献
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Baris Gulcu Derya Ulug Canan Hazir Mehmet Karagoz 《Biocontrol Science and Technology》2014,24(8):965-970
In laboratory studies, we demonstrated that five native entomopathogenic nematode species/isolates caused 100% mortality of Spodoptera cilium larvae, a soil surface-feeding pest of turfgrass. At 25 infective juveniles/cm2 applied to sod, two selected Turkish species, Steinernema carpocapsae and Heterorhabditis bacteriophora (Sarigerme isolate), averaged 77% and 29% larval mortality, respectively. 相似文献
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Mehmet Kaya Nurcan Orhan Emrah Karabacak Metin Berkant Bahceci Nadir Arican Bulent Ahishali Gonul Kemikler Atilla Uslu Aydin Cevik Canan Ugur Yilmaz Mutlu Kucuk Candan Gürses 《Life sciences》2013,92(4-5):289-297
AimsThis study investigates the effects of vagus nerve stimulation (VNS) on seizure severity and blood–brain barrier (BBB) integrity in kindled rats with cortical dysplasia (CD).Main methodsPregnant rats were exposed to 145 cGy of gamma-irradiation on day 17 of pregnancy. In offsprings, kindling was induced by giving subconvulsive doses of pentylenetetrazole. Left VNS was performed for 48 h at output currents of 0.5 or 1 mA. Horseradish peroxidase (HRP) was used to study the BBB permeability. Immunohistochemistry for occludin and P-glycoprotein (P-gp) was also performed.Key findingsKindled rats with CD exhibited seizures with mean Racine's scores of 3.57 ± 1.2 during video EEG recording. Kindled animals with CD receiving VNS at 0.5 and 1.0 mA did not exhibit either clinical or electrophysiological signs of seizure. Immunostaining for occludin, a tight junction protein, in hippocampus remained relatively intact in all groups. VNS-treated and -untreated kindled animals with CD revealed intense immunostaining for P-gp in hippocampal formation (P < 0.01). Electron microscopic observations revealed frequent transport vesicles containing electron-dense HRP reaction products in the cytoplasm of brain capillary endothelial cells in both cerebral cortex and hippocampus of kindled animals with CD. Those which were exposed to 1 mA VNS were observed to have brain capillary endothelial cells largely devoid of HRP reaction products in both cerebral cortex and hippocampus.SignificanceThe results of this study suggest that VNS therapy at 1 mA inhibits seizure activity and protects BBB integrity by limiting the enhancement of transcellular pathway in kindled animals with CD. 相似文献
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Gonullu G Ersoy C Ersoy A Evrensel T Basturk B Kurt E Oral B Gokgoz S Manavoglu O 《Cytokine》2005,31(4):264-269
Insulin resistance (IR) and obesity may be risk factors for breast cancer. The mechanism of IR in patients with cancer has not been fully clarified yet. This study was conducted to evaluate the possible role of circulating cytokines; tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6) in inducing IR in 20 overweight or obese patients with early stage breast cancer and to compare their levels with that of body mass index matched 20 healthy controls. IR was calculated by homeostasis model assessment (HOMA) method. Four groups were formed according to a 2.7 HOMA-IR cut-off value as breast cancer with or without IR and controls with or without IR. IL-6 and HOMA-IR values were found to be higher in breast cancer patients with IR compared to other groups. There was no significant difference in TNF-alpha levels between groups. HOMA-IR values correlated with estradiol and IL-6 levels in all breast cancer patients but not TNF-alpha. HOMA-IR values, serum insulin, estradiol and IL-6 levels in the receptor positive group were significantly higher than those of the receptor negative group. These results suggested a possible contribution of endogenous IL-6 production and hyperinsulinemia to the development of breast cancer in overweight or obese patients with prominent IR. 相似文献
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Shifeng Cheng Erik van den Bergh Peng Zeng Xiao Zhong Jiajia Xu Xin Liu Johannes Hofberger Suzanne de Bruijn Amey S. Bhide Canan Kuelahoglu Chao Bian Jing Chen Guangyi Fan Kerstin Kaufmann Jocelyn C. Hall Annette Becker Andrea Br?utigam Andreas P.M. Weber Chengcheng Shi Zhijun Zheng Wujiao Li Mingju Lv Yimin Tao Junyi Wang Hongfeng Zou Zhiwu Quan Julian M. Hibberd Gengyun Zhang Xin-Guang Zhu Xun Xu M. Eric Schranz 《The Plant cell》2013,25(8):2813-2830
The Brassicaceae, including Arabidopsis thaliana and Brassica crops, is unmatched among plants in its wealth of genomic and functional molecular data and has long served as a model for understanding gene, genome, and trait evolution. However, genome information from a phylogenetic outgroup that is essential for inferring directionality of evolutionary change has been lacking. We therefore sequenced the genome of the spider flower (Tarenaya hassleriana) from the Brassicaceae sister family, the Cleomaceae. By comparative analysis of the two lineages, we show that genome evolution following ancient polyploidy and gene duplication events affect reproductively important traits. We found an ancient genome triplication in Tarenaya (Th-α) that is independent of the Brassicaceae-specific duplication (At-α) and nested Brassica (Br-α) triplication. To showcase the potential of sister lineage genome analysis, we investigated the state of floral developmental genes and show Brassica retains twice as many floral MADS (for MINICHROMOSOME MAINTENANCE1, AGAMOUS, DEFICIENS and SERUM RESPONSE FACTOR) genes as Tarenaya that likely contribute to morphological diversity in Brassica. We also performed synteny analysis of gene families that confer self-incompatibility in Brassicaceae and found that the critical SERINE RECEPTOR KINASE receptor gene is derived from a lineage-specific tandem duplication. The T. hassleriana genome will facilitate future research toward elucidating the evolutionary history of Brassicaceae genomes. 相似文献
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Cécilia Szatkowski Judith Vallet Mojdeh Dormishian Nadia Messaddeq Phillippe Valet Mounia Boulberdaa Daniel Metzger Pierre Chambon Canan G. Nebigil 《PloS one》2013,8(12)