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The neuronal impulse activity during visual testing for orientation sensitivity in different head tilts was recorded in parkinsonian++ patients diagnosed and treated with long-term intracerebral electrodes implanted into different nuclei of the thalamus and striopallidar complex. It was revealed that some neuronal populations responded only to the definite orientation of the stimuli. The "preferable" orientations were not changed for the most orientation-selective neurons during left and right head positions differing by 90 degrees. 相似文献
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F. I. Abdullaev L. Rivern-Negrete H. Caballero-Ortega J. Manuel Hernndez I. Prez-Lpez R. Pereda-Miranda J. J. Espinosa-Aguirre 《Toxicology in vitro》2003,17(5-6):731
Saffron is harvested from the dried, dark red stigmas of Crocus sativus L. flowers. It is used as a spice for flavoring and coloring food and as a perfume. It is often used for treating several diseases. We assessed the antimutagenic, comutagenic and cytotoxic effects of saffron and its main ingredients using the Ames/Salmonella test system, two well known mutagens (BP, 2AA), the in vitro colony formation assay and four different cultured human normal (CCD-18Lu) and malignant (HeLa, A-204 and HepG2) cells. When only using the TA98 strain in the Ames/Salmonella test system, saffron showed non-mutagenic, as well as non-antimutagenic activity against BP-induced mutagenicity, and demonstrated a dose-dependent co-mutagenic effect on 2-AA-induced mutagenicity. The saffron component responsible for this unusual comutagenic effect was safranal. In the in vitro colony formation test system, saffron displayed a dose-dependent inhibitory effect only against human malignant cells. All isolated carotenoid ingredients of saffron demonstrated cytotoxic activity against in vitro tumor cells. Saffron crocin derivatives possessed a stronger inhibitory effect on tumor cell colony formation. Overall, these results suggest that saffron itself, as well as its carotenoid components might be used as potential cancer chemopreventive agents. 相似文献
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Hemorheological indices were studied in 89 patients. In 61 patients the authors have revealed somewhat increased viscosity potential of blood and negligible changes in the aggregation activity of erythrocytes which is thought by the authors to be due to the saved compensatory potentialities of the organism. In 28 patients with the complicated course of the disease the rheological parameters of blood became worse because of the suppressed compensatory potentialities of organism. So, in addition to the adequate transfusion-infusion therapy the complex of treatment must include immunostimulating means (Levamisole, Prodigiozan, Tactivin etc.). 相似文献
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R. Zosiamliana B. Chettri G. S. L. Fabris J. R. Sambrano Sherzod Abdullaev G. Abdurakhmanov D. P. Rai 《RSC advances》2022,12(42):27666
Motivated by our previous work on pristine Na2SiO3, we proceeded with calculations on the structural, electronic, mechanical and piezoelectric properties of complex glass-like Na2Si1−xGexO3 (x = 0.0, 0.25, 0.50, 0.75, 1.0) by using density functional theory (DFT). Interestingly, the optimized bond lengths and bond angles of Na2SiO3 and Na2GeO3 resemble each other with high similarity. On doping we report the negative formation energy and feasibility of transition of Na2SiO3 → Na2GeO3 while the structural symmetry is preserved. Analyzing the electronic profile, we have observed a reduced band gap on increasing x = Ge concentration at Si-sites. All the systems are indirect band gap (Z–Γ) semiconductors. The studied systems have shown mechanical stabilities by satisfying the Born criteria for mechanical stability. The calculated results have shown highly anisotropic behaviour and high melting temperature, which are a signature of glass materials. The piezoelectric tensor (both direct and converse) is computed. The results thus obtained predict that the systems under investigation are potential piezoelectric materials for energy harvesting.Motivated by our previous work on pristine Na2SiO3, we proceeded with calculations on the structural, electronic, mechanical and piezoelectric properties of complex glass-like Na2Si1−xGexO3 (x = 0.0, 0.25, 0.50, 0.75, 1.0) by using density functional theory (DFT). 相似文献
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We review the impact of mitochondrial DNA (mtDNA) maintenance and mitochondrial function on the aging process. Mitochondrial function and mtDNA integrity are closely related. In order to create a protective barrier against reactive oxygen and nitrogen species (RONS) attacks and ensure mtDNA integrity, multiple cellular mtDNA copies are packaged together with various proteins in nucleoids. Regulation of antioxidant and RONS balance, DNA base excision repair, and selective degradation of damaged mtDNA copies preserves normal mtDNA quantities. Oxidative damage to mtDNA molecules does not substantially contribute to increased mtDNA mutation frequency; rather, mtDNA replication errors of DNA PolG are the main source of mtDNA mutations. Mitochondrial turnover is the major contributor to maintenance of mtDNA and functionally active mitochondria. Mitochondrial turnover involves mitochondrial biogenesis, mitochondrial dynamics, and selective autophagic removal of dysfunctional mitochondria (i.e., mitophagy). All of these processes exhibit decreased activity during aging and fall under greater nuclear genome control, possibly coincident with the emergence of nuclear genome instability. We suggest that the age-dependent accumulation of mutated mtDNA copies and dysfunctional mitochondria is associated primarily with decreased cellular autophagic and mitophagic activity. 相似文献