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311.
312.
E Cerasi 《Hormones et métabolisme》2002,34(2):107-8; author reply 109-10
313.
B Y Klein R Nesher E Cerasi 《Biochemical and biophysical research communications》1986,136(2):638-644
L cells (tk-) were cotransfected with total genomic rat islet DNA and a plasmid containing thymidine kinase gene (ptk). Transfectants were tested for their ability to release insulin into the medium. At least 10% of the colonies contained immunoreactive insulin (IRI) during the initial two weeks. The insulin secreted competed linearly with rat insulin in RIA, the majority of the insulin antigenicity comigrating with rat insulin on G-50 Sephadex chromatography. With continuing propagation the IRI activity diminished; however 3 selected cultures demonstrated increased secretion of IRI following stimulation with glucose. These findings indicate that glucose-induced insulin secretion can be obtained in non-beta cells; however the frequency of success was below one stable transfection for every 5 X 10(8) Ltk- cells exposed to the transfection procedure. 相似文献
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315.
316.
Is the alpha rhythm a control parameter for brain responses? 总被引:4,自引:0,他引:4
Erol Bas¸ar Juliana Yordanova Vasil Kolev Canan Bas¸ar-Eroglu 《Biological cybernetics》1997,76(6):471-480
The main goal of the present study is to develop a conceptual analysis of alpha response in the brain based on single sweep
evaluation. A new method was employed to estimate a set of single-sweep parameters and quantify the oscillatory behaviour
of single, electroencephalograph (EEG) sweeps. It was aimed to demonstrate that brain alpha responses are governed by spontaneous
alpha activity and to validate the principle of brain response excitability. Because the spontaneous alpha activity depends
on both the topology of recording and the subject’s age, topology and age models were used. Spontaneous and evoked alpha activity
were recorded at frontal and occipital sites in three groups of subjects: 3-year-old children, young adults and middle-aged
subjects. Amplitude, enhancement and phase-locking of single alpha responses to visual stimuli were analysed. Major results
showed that: (1) visual alpha responses could be recorded only if the alpha rhythm was developed in the spontaneous EEG independent
of electrode location; (2) middle-aged adults showed more expressed frontal spontaneous alpha activity in comparison with
young adults; (3) accordingly, alpha responses with higher amplitude and stronger phase-locking were produced over the frontal
brain area in middleaged than young adults. These results validate the principle of brain response excitability and demonstrate
that a shift towards frontal brain areas for both the spontaneous and evoked alpha activity occurs with increasing age in
adults. The results are discussed in the context of the diffuse and distributed alpha system of the brain. Age-dependent changes
in frontal alpha activity are suggested to be related to frontal brain functioning during aging.
Received: 6 November 1995 / Accepted in revised form: 13 March 1997 相似文献
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318.
In this study, Crocus ancyrensis was extracted from different parts of the plants with various solvents and their antioxidant activities and phenolic contents were investigated in detail for the first time. The highest amount of total phenolic substance in all parts of the plant was determined in the stigmaless flower. In the DPPH and FRAP methods, the highest antioxidant activity was obtained from the water extraction from the plant. Rutin is the highest detected by LC MS/MS. Stigmaless flower extract in all solvents is attributed to the component that contributes the most to antioxidant capacity. p-hydroxy benzoic acid was detected as the highest phenolic component after rutin. When the antioxidant activity results were examined, it was determined that the highest activity was in the water extract. As a result, it is evaluated that rutin and p-hydroxybenzoic acid in the plant contribute to the antioxidant capacity. 相似文献
319.
Michael J. Conway Alan M. Watson Tonya M. Colpitts Srdjan M. Dragovic Zhiyong Li Penghua Wang Fabiana Feitosa Denueve T. Shepherd Kate D. Ryman William B. Klimstra John F. Anderson Erol Fikrig 《Journal of virology》2014,88(1):164-175
Dengue virus (DENV), a flavivirus of global importance, is transmitted to humans by mosquitoes. In this study, we developed in vitro and in vivo models of saliva-mediated enhancement of DENV infectivity. Serine protease activity in Aedes aegypti saliva augmented virus infectivity in vitro by proteolyzing extracellular matrix proteins, thereby increasing viral attachment to heparan sulfate proteoglycans and inducing cell migration. A serine protease inhibitor reduced saliva-mediated enhancement of DENV in vitro and in vivo, marked by a 100-fold reduction in DENV load in murine lymph nodes. A saliva-mediated infectivity enhancement screen of fractionated salivary gland extracts identified serine protease CLIPA3 as a putative cofactor, and short interfering RNA knockdown of CLIPA3 in mosquitoes demonstrated its role in influencing DENV infectivity. Molecules in mosquito saliva that facilitate viral infectivity in the vertebrate host provide novel targets that may aid in the prevention of disease. 相似文献
320.
Erol ?akmak Hakan Alagozlu Cesur Gumus Celiks?z Alí 《The Korean journal of parasitology》2013,51(4):475-477
Although alveolar echinococcosis (AE) can cause a serious disease with high mortality and morbidity similar to malign neoplasms. A 62-year-old woman admitted to a hospital located in Sivas, Turkey, with the complaints of fatigue and right upper abdominal pain. On contrast abdominal CT, a 54×70×45 mm sized cystic lesion was detected in the left lobe of the liver that was seen to extend to the posterior mediastinum and invade the diaphragm, esophagus, and pericardium. The cystic lesion was seen to be occluding the inferior vena cava and left hepatic vein at the level where the hepatic veins poured into the inferior vena cava. Bilateral pleural effusion was also detected. We discussed this secondary Budd-Chiari Syndrome (BCS) case, resulting from the AE occlusion of the left hepatic vein and inferior vena cava, in light of the information in literature. 相似文献