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991.
This study tested whether differences in sensitivity between the upper and lower olfactory epithelia of Solea senegalensis are associated with different odorant receptors and transduction pathways, using the electro‐olfactogram. Receptor mechanisms were assessed by cross‐adaptation with amino acids (L‐cysteine, L‐phenylalanine and 1‐methyl‐L‐tryptophan) and bile acids (taurocholic acid and cholic acid). This suggested that relatively specific receptors exist for 1‐methyl‐L‐tryptophan and L‐phenylalanine (food‐related odorants) in the lower epithelium, and for taurocholic acid (conspecific‐derived odorant) in the upper. Inhibition by U73122 [a phospholipase C (PLC) inhibitor] suggested that olfactory responses to amino acids were mediated mostly, but not entirely, by PLC‐mediated transduction (IC50; 15–55 nM), whereas bile acid responses were mediated by both PLC and adenylate cyclase–cyclic adenosine monophosphate (AC–cAMP) (using SQ‐22536; an AC inhibitor). Simultaneous application of both drugs rarely inhibited responses completely, suggesting possible involvement of non‐PLC and non‐AC mediated mechanisms. For aromatic amino acids and bile acids, there were differences in the contribution of each transduction pathway (PLC, AC and non‐PLC and non‐AC) between the two epithelia. These results suggest that differences in sensitivity of the two epithelia are associated with differences in odorant receptors and transduction mechanisms. 相似文献
992.
In this paper, we propose a full-reference (FR) image quality assessment (IQA) scheme, which evaluates image fidelity from two aspects: the inter-patch similarity and the intra-patch similarity. The scheme is performed in a patch-wise fashion so that a quality map can be obtained. On one hand, we investigate the disparity between one image patch and its adjacent ones. This disparity is visually described by an inter-patch feature, where the hybrid effect of luminance masking and contrast masking is taken into account. The inter-patch similarity is further measured by modifying the normalized correlation coefficient (NCC). On the other hand, we also attach importance to the impact of image contents within one patch on the IQA problem. For the intra-patch feature, we consider image curvature as an important complement of image gradient. According to local image contents, the intra-patch similarity is measured by adaptively comparing image curvature and gradient. Besides, a nonlinear integration of the inter-patch and intra-patch similarity is presented to obtain an overall score of image quality. The experiments conducted on six publicly available image databases show that our scheme achieves better performance in comparison with several state-of-the-art schemes. 相似文献
993.
Sevda Tanrikulu Evin Ademoglu Figen Gurdol Umit Mutlu‐Turkoglu Ahmet Kaya Bilge Yilmaz Nisanci 《Cell biochemistry and function》2009,27(7):452-457
In Turkish population, plasma HDL‐C levels were found to be lower than in any other country and it is suggested that this is associated with genetic origin. The cholesteryl ester transfer protein (CETP) ?629C > A polymorphism is associated with lower plasma CETP concentration, with increased HDL‐C level. In the present study, the frequency of ?629C > A polymorphism in patients with coronary artery disease (CAD) was investigated and the effect of genotype on HDL‐C was evaluated in a Turkish population. For this aim CETP ?629C > A polymorphism was studied in angiographically documented CAD patients and healthy controls. There was no statistical significance in the distribution of genotypes between patients and controls. Although A allele carriers with CAD had significantly lower HDL‐C levels than controls, plasma lipid levels showed no difference according to the genotypes. Adjustment by a logistic regression model predicting CAD status through HDL‐C and including some risk factors as covariate indicated that the HDL‐C doesn't have a significant association with CAD risk in CA and AA genotype carriers. Smoking, gender and hypertension were the common predictors for the HDL‐C levels in CA and AA carriers. Although HDL‐C appeared to be the only significant predictor of CAD in our study groups, the contribution of CETP ?629C > A polymorphism to the alterations in HDL‐C level appears to be weak to mention a protective effect of this polymorphism for CAD. In conclusion, the findings of the present study indicate that the CETP ?629C > A polymorphism is not among the determinants of the coronary artery disease in Turks. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
994.
995.
Aquatic plants are used as a practical and effective method to remove toxic elements from secondary-treated municipal wastewater. In this study, Lemna gibba was investigated for its capacity to remove uranium, arsenic, and boron from secondary effluents. L. gibba was collected from a natural lake in Elaz??, Turkey, then acclimatized to the effluent in situ. The concentration of toxic elements in the plant material was monitored as a function of time for 7 days. L. gibba significantly accumulated the toxic elements, particularly in the first 2 days. Arsenic, uranium, and boron were accumulated in the highest concentrations (133%, 122%, and 40%, respectively). However, in the following days, accumulation levels showed both increases and decreases, most probably due to L. gibba reaching saturation levels. 相似文献
996.
In this study, the Phanerotomini of Turkey collected between July 1959 and July 2004, are listed. A total of thirteen Phanerotomini
species were determined, and six of these are reported for the first time from Turkey. Phanerotoma (Bracotritoma) permixtellae Fischer, 1968 was reared from a new natural host Recurvaria pistaciicola (Danilevskii, 1955) (Lepidoptera: Gelechiidae). With this present study an illustrated identification key for the Phanerotomini
of Turkey is given. The distribution of the Phanerotomini species is discussed according to the phytogeographical provinces
of Turkey. 相似文献
997.
Ahmet Yilmaz Coban 《Memórias do Instituto Oswaldo Cruz》2014,109(2):246-249
The aim of this study was to investigate the performance of a new and accurate method
for the detection of isoniazid (INH) and rifampicin (RIF) resistance among
Mycobacterium tuberculosis isolates using a crystal violet
decolourisation assay (CVDA). Fifty-five M. tuberculosis isolates
obtained from culture stocks stored at -80ºC were tested. After bacterial
inoculation, the samples were incubated at 37ºC for seven days and 100 µL of CV (25
mg/L stock solution) was then added to the control and sample tubes. The tubes were
incubated for an additional 24-48 h. CV (blue/purple) was decolourised in the
presence of bacterial growth; thus, if CV lost its colour in a sample containing a
drug, the tested isolate was reported as resistant. The sensitivity, specificity,
positive predictive value, negative predictive value and agreement for INH were
92.5%, 96.4%, 96.1%, 93.1% and 94.5%, respectively, and 88.8%, 100%, 100%, 94.8% and
96.3%, respectively, for RIF. The results were obtained within eight-nine days. This
study shows that CVDA is an effective method to detect M.
tuberculosis resistance to INH and RIF in developing countries. This
method is rapid, simple and inexpensive. Nonetheless, further studies are necessary
before routine laboratory implementation. 相似文献
998.
A new subspecies, Klasea serratuloides (DC.) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on stony places in the Ayranc? and Ermenek district (C4 Karaman Province), Ere?li district (C5 Konya province) and Uluk??la (C5 Ni?de province) in the central and south Anatolia transition zone. It is morphologically similar to K. serratuloides subsp. serratuloides. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distribution of the new subspecies and other related species is mapped. The pollen morphology and achene surface of K. serratuloides subsp. karamanica and K. serratuloides subsp. serratuloides were examined by SEM. 相似文献
999.
Figen Amber Cicek Aysegul Toy Erkan Tuncay Belgin Can Belma Turan 《Journal of bioenergetics and biomembranes》2014,46(5):377-387
Current data support that pharmacological modulators of endoplasmic reticulum stress (ERS) have therapeutic potential for diabetic individuals. Therefore, we aimed to examine whether timolol, having free radical-scavenger action, besides being a β-blocker, exerts a cardioprotective effect via inhibition of ERS response in diabetic rats in a comparison with an antioxidant N-acetylcysteine (NAC). Histopathological data showed that either timolol- or NAC-treatment of diabetic rats prevented the changes in mitochondria and nucleus of the cardiac tissue while they enhanced the cellular redox-state in heart as well. The levels of ER-targeted cytoprotective chaperones GRP78 and calnexin, unfolded protein response signaling protein CHO/Gadd153 besides the levels of calpain, BCL-2, phospho-Akt, PUMA, and PML in the hearts from diabetic rats, treated with either timolol or NAC, are found to be similar among these groups, although all these parameters were markedly preserved in the untreated diabetics compared to those of the controls. Taken into consideration how important a balanced-ratio between anti-apoptotic and pro-apoptotic proteins for the maintenance mitochondria/ER function, our results suggest that ERS in diabetic rat heart is mediated by increased oxidative damage, which in turn triggers cardiac dysfunction. Moreover, we also demonstrated that timolol treatment of diabetic rats, similar to NAC treatment, induced a well-controlled redox-state and apoptosis in cardiac myocardium. We, thus for the first time, report that cardioprotective effect of timolol seems to be associated with normalization of ER function due to its antioxidant action in cardiomyocytes even under hyperglycemia. 相似文献
1000.
High summer temperature negatively affects cotton yield, and better understanding of genetic mechanisms of heat stress responses in cotton may facilitate development of new heat tolerant cultivars. We attempted to determine heat responsive genes in cotton using tolerant (Stoneville 453, BA 119) and susceptible (Nazilli 84S) cultivars. Twenty five expressed sequence tags (ESTs) were sequenced and studied for gene homology. Sixteen ESTs were significantly similar to known genes, whereas eight ESTs were similar to not annotated cDNA clones and 1 EST did not show homology to any known gene. Expression of some ESTs was analyzed by quantitative real-time PCR and IAA-ala hydrolase (IAR3), folylpolyglutamate synthase (FPGS3), and two not annotated ESTs (GhHS126 and GhHS128) were consistently up-regulated under both short- and long-term heat stress. Since cotton is considered relatively more heat tolerant than most of the other crops, it can be suggested that these genes and ESTs could play a significant role in heat tolerance. In addition, GhHS126 and GhHS128 might be parts of the new candidate genes for heat tolerance. 相似文献