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排序方式: 共有378条查询结果,搜索用时 31 毫秒
361.
Nehir Kaymak Kirk O. Winemiller Senol Akin Zekeriya Altuner Fatih Polat Tarik Dal 《Hydrobiologia》2015,753(1):131-147
362.
Gulhan Yasar Unzile Guven Gulhan Elif Guduk Fatih Aktas 《Biocatalysis and Biotransformation》2020,38(5):367-375
AbstractLipases are one of the most important catalysts for several industries such as detergent, dairy, and textile industry due to their bio-catalytic ability in aqueous and non-aqueous media. Stability to extreme conditions is an important property since it makes enzymes suitable to several industrial processes. In this study, lipase producing soil bacteria were screened and identified with 16S rDNA sequencing. A new hyper-thermophilic lipase named as Bacillus subtilis LP2 isolate was partially purified by ammonium sulphate precipitation with 17.8-fold purification and 583?U/mg specific activity. Maximum activity was exhibited at pH 7 and 80?°C with the substrate tween 80?KM and Vmax values were calculated as 18.3?mM and 680?U/mg with a catalytic efficiency (kcat/KM) of 307?s?1M?1. These results indicate that lipase from Bacillus subtilis LP2 can be a valuable candidate for industrial applications such as organic synthesis and fats and oils industry due to their efficient catalysis in higher temperatures. 相似文献
363.
Fatih Kaburcuk 《Electromagnetic biology and medicine》2019,38(2):168-176
In this paper, effects of a brain tumor located in a dispersive human head model on specific absorption rate (SAR) and temperature rise distributions due to different types of RF sources at 4G and 5G cellular frequencies are investigated with the use of a multiphysics model. This multiphysics model analyzes the dispersive human head with the brain tumor and provides the SAR and temperature rise distributions in the head due to the RF source operated at 4G and 5G cellular frequencies in a single finite-difference time-domain simulation. An adjacent antenna operated at 4G and 5G cellular frequencies to the human head is considered as the RF source for near-field exposure, while a plane wave field radiated by base stations operated at 4G and 5G cellular frequencies is considered as the RF source for far-field exposure. Numerical results show that the brain tumor in the head slightly affects the SAR and temperature rise distributions due to different RF sources at 4G and 5G cellular frequencies. 相似文献
364.
We use genomics to identify the natal origin of a grey whale found in the South Atlantic, at least 20 000 km from the species core range (halfway around the world). The data indicate an origin in the North Pacific, possibly from the endangered western North Pacific population, thought to include only approximately 200 individuals. This contributes to our understanding of Atlantic sightings of this species known primarily from the North Pacific, and could have conservation implications if grey whales have the potential for essentially global dispersion. More broadly, documenting and understanding rare extreme migration events have potential implications for the understanding of how a species may be able to respond to global change. 相似文献
365.
Assoc. Prof. Dr. Gülsen Tel-Çayan Begüm Hazar Çiftçi Meltem Taş-Küçükaydın Yeşim Temel Dr. Fatih Çayan Dr. Selçuk Küçükaydın Prof. Dr. Mehmet Emin Duru 《化学与生物多样性》2023,20(9):e202300990
The objectives of the present study are to compare the phenolic profiles and biological activities of 15 citrus honey samples from three different locations in Turkey using a chemometric approach. The HPLC-DAD analysis was used to determine phenolic profiles. Nineteen phenolic compounds were identified. Gallic acid (107.14–717.04 μg/g) was recorded as the predominant compound. AF (Antalya-Finike) had the highest antioxidant activity in ABTS⋅+ (IC50: 18.01±0.69 mg/mL), metal chelating (IC50: 6.20±0.19 mg/mL) and CUPRAC (A0.50: 12.05±0.68 mg/mL) assays, while it revealed the best anti-inflammatory activity against COX-2 (17.28±0.22 %) and COX-1 (43.28±0.91 %). AM (Antalya-Manavgat) was the most active in β-carotene-linoleic acid (IC50: 10.05±0.19 mg/mL), anti-urease (38.90±0.69 %), anti-quorum sensing and antimicrobial activities. AKO1 (Adana-Kozan-1) in DPPH⋅ (IC50: 34.25±0.81 mg/mL) assay, AKU1 (Antalya-Kumluca-1) in tyrosinase inhibition activity (37.73±0.38 %) assay, AKU2 (Antalya-Kumluca-2) in AChE (10.55±0.63 %) and BChE (9.18±0.45 %) inhibition activity assays showed the best activity. Chemometric tools were applied to the phenolic compositions and biological properties. PCA and HCA ensured that 15 citrus honey samples were grouped into 3 clusters. The results showed that myricetin, kaempferol, vanillin, protocatechuic acid, rosmarinic acid, rutin, vanillic acid, gallic acid, catechin and p-hydroxyphenyl acetic acid are phenolic compounds that can be used in the classification of citrus honeys. 相似文献
366.
367.
Chunshui Zhou Fatih Arslan Susan Wee Srinivasan Krishnan Alexander R Ivanov Anna Oliva Janet Leatherwood Dieter A Wolf 《BMC biology》2005,3(1):14
Background
PCI/MPN domain protein complexes comprise the 19S proteasome lid, the COP9 signalosome (CSN), and eukaryotic translation initiation factor 3 (eIF3). The eIF3 complex is thought to be composed of essential core subunits required for global protein synthesis and non-essential subunits that may modulate mRNA specificity. Interactions of unclear significance were reported between eIF3 subunits and PCI proteins contained in the CSN. 相似文献368.
Fatih Erci Rabia Cakir-Koc Mustafa Yontem Emrah Torlak 《Preparative biochemistry & biotechnology》2020,50(6):538-548
AbstractIn this study, we aimed to synthesize copper oxide nanoparticles (CuONPs) mediated by plant extract in an environmentally friendly way and to reveal their potential biological activities. Here we synthesized CuONPs by using different concentrations of aqueous leaf extract of Thymbra spicata at 80?°C to obtain Ts1CuONPs and Ts2CuONPs. Biosynthesized nanoparticles were characterized by using UV-Vis, AFM, FTIR, SEM-EDS, TEM, DLS and zeta potential analysis. The antibacterial activity of the nanoparticles was determined by calculation of the inhibition zone and minimum inhibitory concentration against selected bacterial strains. Moreover, the antioxidant activity of the as-synthesized nanoparticles was evaluated based on DPPH radical scavenging activity. The results indicate that the as-synthesized NPs have an average size of 26.8 and 21?nm for Ts1CuONPs and Ts2CuONPs, respectively. The formed CuONPs have more antibacterial action on gram-positive bacteria compared to gram-negative bacteria. In addition, CuONPs demonstrated good inhibition activity against biofilm formation of Staphylococcus aureus (S. aureus). Furthermore, the results showed that the smaller size of the CuONPs caused the higher cytotoxicity on L929 mouse fibroblast cells. The as-synthesized CuONPs exhibit antibacterial and antibiofilm potential against S. aureus, indicating that they may be attractive candidates to use in future therapeutic applications. 相似文献
369.
370.
MEIS proteins are historically associated with tumorigenesis, metastasis, and invasion in cancer. MEIS and associated PBX-HOX proteins may act as tumor suppressors or oncogenes in different cellular settings. Their expressions tend to be misregulated in various cancers. Bioinformatic analyses have suggested their upregulation in leukemia/lymphoma, thymoma, pancreas, glioma, and glioblastoma, and downregulation in cervical, uterine, rectum, and colon cancers. However, every cancer type includes, at least, a subtype with high MEIS expression. In addition, studies have highlighted that MEIS proteins and associated factors may function as diagnostic or therapeutic biomarkers for various diseases. Herein, MEIS proteins and associated factors in tumorigenesis are discussed with recent discoveries in addition to how they could be modulated by noncoding RNAs or newly developed small-molecule MEIS inhibitors. 相似文献