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Content of malondialdehyde (MDA), proline, phenolics, and saccharides was analyzed during different developmental stages of in vitro root and shoot organogenesis in saffron. The highest content of MDA, proline, and phenolics was detected in nodular calli. Significant changes were also found in the content of polysaccharides, soluble saccharides, oligosaccharides, and reducing saccharides during developmental stages. Histological investigation of nodular calli showed meristematic zones with small and densely stained cells situated at peripheral zones of calli. The meristematic zones surrounded some vascular areas from which de novo organs originated. The parenchymatic cells of inner zones of calli converted to procambium cells that produced vascular tissues.  相似文献   
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Abstract: We examined the effects of orally administered 5'-cytidinediphosphocholine (CDP-choline) on arterial plasma choline and cytidine levels and on brain phospholipid composition in rats. Animals receiving a single oral dose of 100, 250, or 500 mg/kg showed peak plasma choline levels 6–8 h after drug administration (from 12 ± 1 to 17 ± 2, 19 ± 2, and 24 ± 2 µ M , respectively). The area under the plasma choline curve at >14 µ M , i.e., at a concentration that induces a net influx of choline into the brain, was significantly correlated with CDP-choline dose. In rats receiving 500 mg/kg this area was 2.3 times that of animals consuming 250 mg/kg, which in turn was 1.8 times that of rats receiving 100 mg/kg. Plasma cytidine concentrations increased 5.4, 6.5, and 15.1 times baseline levels, respectively, 8 h after each of the three doses. When the oral CDP-choline treatment was prolonged for 42 and 90 days, brain phosphatidylcholine concentrations increased significantly (by 22–25%; p < 0.05) in rats consuming 500 mg/kg/day. Brain phosphatidylethanolamine and phosphatidylserine concentrations also increased significantly under some experimental conditions; levels of other phospholipids were unchanged.  相似文献   
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Precise localization of epileptic foci is an unavoidable prerequisite in epilepsy surgery. Simultaneous EEG-fMRI recording has recently created new horizons to locate foci in patients with epilepsy and, in comparison with single-modality methods, has yielded more promising results although it is still subject to limitations such as lack of access to information between interictal events. This study assesses its potential added value in the presurgical evaluation of patients with complex source localization. Adult candidates considered ineligible for surgery on account of an unclear focus and/or presumed multifocality on the basis of EEG underwent EEG-fMRI. Adopting a component-based approach, this study attempts to identify the neural behavior of the epileptic generators and detect the components-of-interest which will later be used as input in the GLM model, substituting the classical linear regressor. Twenty-eight sets interictal epileptiform discharges (IED) from nine patients were analyzed. In eight patients, at least one BOLD response was significant, positive and topographically related to the IEDs. These patients were rejected for surgery because of an unclear focus in four, presumed multifocality in three, and a combination of the two conditions in two. Component-based EEG-fMRI improved localization in five out of six patients with unclear foci. In patients with presumed multifocality, component-based EEG-fMRI advocated one of the foci in five patients and confirmed multifocality in one of the patients. In seven patients, component-based EEG-fMRI opened new prospects for surgery and in two of these patients, intracranial EEG supported the EEG-fMRI results. In these complex cases, component-based EEG-fMRI either improved source localization or corroborated a negative decision regarding surgical candidacy. As supported by the statistical findings, the developed EEG-fMRI method leads to a more realistic estimation of localization compared to the conventional EEG-fMRI approach, making it a tool of high value in pre-surgical evaluation of patients with refractory epilepsy. To ensure proper implementation, we have included guidelines for the application of component-based EEG-fMRI in clinical practice.  相似文献   
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Neurochemical Research - Evidence has shown the beneficial effects of exercise on learning and memory. However, many studies have reported controversial results, indicating that exercise can impair...  相似文献   
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Abstract

One of the major environmental problems nowadays is petroleum hydrocarbons contamination. Bioremediation is widely used for cleaning ecosystems contaminated with petroleum hydrocarbons. This study was carried out to investigate the response of five microalgae strains isolated from different regions in Iran for 1% n-dodecane (DOD) degradation. The results revealed that Leptolyngbya fragilis ISC 108 is the most effective strain to utilize n-DOD as growth substrate under a mixotrophic condition. Currently, there is little information about mechanisms involved in microalgae response against DOD. The activity of antioxidant enzymes and total lipid and carbohydrate contents were observed to be greater in DOD-treated L. fragilis ISC 108. Lower values of lipid peroxidation and H2O2 along with an increase of dry weight and specific growth rate in L. fragilis ISC 108 under DOD treatment shows that at the cellular level this strain is better equipped with an efficient oxygen radical scavenging system. In conclusion, this study proposes that L. fragilis ISC 108 can be considered an ideal candidate for use in bioremediation of DOD contaminated sites.  相似文献   
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