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91.
Coşkun S Karataş F Acartürk F Olmuş H Selvi M Erbaş D 《Molecular and cellular biochemistry》2005,278(1-2):65-69
The aim of the current study was to comparatively investigate the effect of inhibition of nitric oxide (NO) production by
N-nitro-L-arginine methyl ester (L-NAME), an isoform non-specific inhibitor of nitric oxide synthase (NOS), after oral mucosal
incision on wound tissue NO levels. A standard incision was applied to the oral mucosa of rabbits. After oral mucosal incision,
rabbits were divided into five groups as follows: (1) Untreated incisional group (control); (2) Titanium (Ti) implanted group;
(3) Ti + Polyethylene glycol (PEG) 4000 implanted group; (4) Ti + PEG 4000 + L-NAME (2 × 10−4 M) implanted group and (5) i.p. L-NAME administrated group (10 mg/kg). At 5 days after oral incision operations, wound tissue
strips and plasma were obtained from rabbits. Oral wound tissue and plasma nitric oxide, plasma thiobarbituric acid reactive
substances (TBARS) and total sulfhydryl group (RSH) levels were investigated. Plasma TBARS and NOx levels decreased after
i.p. L-NAME administration. Total RSH group levels were not changed in all groups (p>0.05). This means that L-NAME inhibits the deteriorating effects of free radicals without affecting healing. L-NAME in PEG
and titanium also has no effect on tissue and plasma NOx levels. These findings indicate that NO generation will not be affected
both Ti and local nitric oxide synthase (NOS) inhibitor. (Mol Cell Biochem 278: 65–69, 2005) 相似文献
92.
93.
Yelda Güzel Ekrem Aktoklu Vincent Roumy Racha Alkhatib Thierry Hennebelle François Bailleul Sevser Şahpaz 《Biochemical Systematics and Ecology》2011,39(4-6):781-786
The flavonoid profiles of Turkish Torilis Gaertn. (Apiaceae) species were studied by TLC, HPLC-UV and HPLC/ESI/MS2 (negative mode). O-glycosides of luteolin, apigenin and chrysoeriol were identified from crude extracts with the help of mass spectra in different MS/MS modes, such as full scan, precursor ion scan and product ion scan. Luteolin-7-O-glucoside and luteolin-7-O-rutinoside were common to all species. Flavonoid profiles usually differ from one species to another and can be put to use for a genus such as Torilis which has been little studied. By the help of different flavonoid profiles, it is concluded that, the plants, which are recognised as less rayed subspecies of Torilis arvensis (Huds.) Link. in various floras including Turkish one, must be classified in species category as Torilis chrysocarpa and Torilis purpurea. Flavonoid profiles seem to be in relation with evolutionary biogeography of the species. Because the most isolated species of the genus, endemic Torilis triradiata, has the most different flavonoid pattern. Moreover, geographically isolated species, T. triradiata and Torilis leptocarpa, do not share any flavonoid except for the two which are common to all species. 相似文献
94.
95.
Mustafa Şahin Asena Gökçay Canpolat Demet Çorapçioğlu Rıfat Emral Ali Rıza Uysal 《Biomarkers》2013,18(8):742-747
AbstractBackground: Hyperthyroidism is associated with increased metabolic activity and thermogenesis. Irisin is a key molecule in thermogenesis and energy expenditure via adipose tissue browning. Epicardial fat was previously defined as brown-like fat. Thus, here we aimed to evaluate the association between serum irisin level and epicardial fat thickness (EFT) in patients with hyperthyroidism.Methods: A total of 25 hyperthyroid patients and 24 age-, sex- and BMI-matched healthy controls were enrolled. Serum irisin levels, thyroid hormone levels, and body compositions were compared. EFT was measured via transthoracic echocardiography.Results: Serum irisin level and EFT were significantly higher in the hyperthyroid group (p?<?0.001 and p?=?0.001, respectively). The distributions of fat-free mass, muscle mass and fat mass were similar between the study groups. Serum irisin level was negatively correlated with TSH (p?<?0.001) and positively correlated with fT3 (p?<?0.001), fT4 (p?<?0.001) and TSH receptor antibody (p?=?0.002) levels and EFT (p?=?0.001). In multivariate linear regression analysis, TSH (β?=??0.475, p?<?0.001) and EFT (β?=?0.290, p?=?0.023) levels were significantly associated with serum irisin levels.Conclusions: An increased serum irisin level associated with EFT might contribute to metabolic derangement in hyperthyroidism. Further studies are needed to elucidate whether irisin levels and EFT are affected by hyperthyroidism or vice versa. 相似文献
96.
Failure modes and effects analysis (FMEA) is a step-by-step approach for identifying all possible failures in a design, a manufacturing or assembly process, or a product or service. The purpose of the FMEA is to take actions to eliminate or reduce failures, starting with the highest-priority ones. This article presents a basis for prioritizing the healthcare problems using FMEA with linguistic variables and fuzzy if–then rules. Severity rating of healthcare problems is handled under the categories of catastrophic, major, moderate, and minor events. MATLAB 2007 is used to obtain the results of fuzzy if–then rules for prioritizing healthcare failures. A numerical example is given for four possible healthcare problems to be prioritized, which are wrong patient, delay in therapy, wrong analgesic selection, and wrong drug. 相似文献
97.
A strain isolated from waste of a milk products plant and exhibited extracellular lipolytic activity was identified as Debaryomyces hansenii by 5.8S rRNA and 28S rRNA gene sequence analyses. Lipolytic activity was assayed spectrophotometrically by using p-nitrophenylpalmitate. Higher specific lipolytic activities were obtained in the presence of tristearin (0.68 U/mg prot), oleic acid (0.56 U/mg prot), and soybean oil (0.36 U/mg prot) than other triglycerides, fatty acids, and vegetable oils considered as carbon sources. Cheese whey appeared to be a good alternative to lipidic substances for lipolytic activity. Among various organic and inorganic nitrogen sources, soy flour was found to attain the lipolytic activity similar to that provided by universal yeast medium components. This work is the first report on the discussion of lipolytic activity enhancement by D. hansenii through modulating the cultivation medium. It also proposes low cost medium nutrients that could be of industrial value and could serve as basal nutrients for further optimization studies on the lipase production by D. hansenii. 相似文献
98.
Ramiz Demir Umut Şahar Remziye Deveci 《Biochimica et Biophysica Acta - Proteins and Proteomics》2021,1869(2):140559
Reelin (400 kDa) is an extracellular matrix glycoprotein that is a key regulator of the many significant biological processes including the brain formation, cell aggregation, and dendrite formation. The glycosylation contributes to the nature of the protein through folding, localization and trafficking, solubility, antigenicity, biological activity, and half-life. Although reelin is to be known as a glycoprotein, the knowledge of its glycosylation is very limited. In this study, we aimed to characterize the terminal glycan profile of reelin by lectin blotting and monosaccharide analysis of glycan chains by capillary liquid chromatography electrospray ionization ion trap tandem mass spectrometry (CapLC-ESI-MS/MS) in SH-SY5Y neuroblastoma cell line. According to our results, reelin was detected in different protein fragments (310, 250, and 85 kDa) in addition to full-length form (400 kDa) in the cell line. The reelin glycoprotein was found to carry the β-N-Acetylglucosamine, α-Mannose, β-Galactose, and α-2,3 and α2,6 linked sialic acids by lectin blotting. Nevertheless, these terminal monosaccharides were found in different intensity according to reelin fragments. Besides, we purified a reelin fragment (250 kDa), and we analyzed it for their monosaccharide by CapLC-ESI-MS/MS. We found that reelin contained five types of monosaccharides, which were consisted of N-Acetylgalactosamine, N-Acetylglucosamine, Galactose, Glucose, Mannose and Sialic acid, from high to low abundance respectively. The present results provide a valuable guide for biochemical, genetic, and glycobiology based further experiments about reelin glycosylation in cancer perspective. 相似文献
99.
Background
Numerous studies have been conducted regarding a heartbeat classification algorithm over the past several decades. However, many algorithms have also been studied to acquire robust performance, as biosignals have a large amount of variation among individuals. Various methods have been proposed to reduce the differences coming from personal characteristics, but these expand the differences caused by arrhythmia.Methods
In this paper, an arrhythmia classification algorithm using a dedicated wavelet adapted to individual subjects is proposed. We reduced the performance variation using dedicated wavelets, as in the ECG morphologies of the subjects. The proposed algorithm utilizes morphological filtering and a continuous wavelet transform with a dedicated wavelet. A principal component analysis and linear discriminant analysis were utilized to compress the morphological data transformed by the dedicated wavelets. An extreme learning machine was used as a classifier in the proposed algorithm.Results
A performance evaluation was conducted with the MIT-BIH arrhythmia database. The results showed a high sensitivity of 97.51%, specificity of 85.07%, accuracy of 97.94%, and a positive predictive value of 97.26%.Conclusions
The proposed algorithm achieves better accuracy than other state-of-the-art algorithms with no intrasubject between the training and evaluation datasets. And it significantly reduces the amount of intervention needed by physicians. 相似文献100.