نتایج جستجو برای: x ray irradiation
تعداد نتایج: 719621 فیلتر نتایج به سال:
We investigated the effect of SCF, a c-kit ligand, on the radiosensitivity of HL60 cells. X-ray-induced apoptosis in HL60 cells was significantly lower in the presence of SCF than in the absence of SCF. This attenuation of X-ray-induced apoptosis by SCF was abolished by PD98059 (an ERK inhibitor), but not by wortmannin (a PI3-K inhibitor) or GF109203X (a PKC inhibitor). The expression of phosph...
Sub-fossilised remains may still contain highly degraded ancient DNA (aDNA) useful for palaeogenetic investigations. Whether X-ray computed [micro-] tomography ([μ]CT) imaging of these fossils may further damage aDNA remains debated. Although the effect of X-ray on DNA in living organisms is well documented, its impact on aDNA molecules is unexplored. Here we investigate the effects of synchrot...
We report simultaneous X-ray and optical observations of V404 Cyg in quiescence. The X-ray flux varied dramatically by a factor of & 20 during a 60 ks observation. X-ray variations were well correlated with those in Hα, although the latter include an approximately constant component as well. Correlations can also be seen with the optical continuum, although these are less clear. We see no large...
Some effects of irradiation on time-dependent accretion-disk models for black hole X-ray novae are presented. Two types of irradiation are considered: direct irradiation from the inner hot disk and indirect irradiation as might be reflected by a corona or chromosphere above the disk. The shadowing effect of the time-dependent evolution of the disk height and consequent blocking of the outer dis...
Chemoradiation therapy (CRT), a combination of X-ray irradiation and anticancer agents as a radiosensitizer, has been found to be an effective treatment for esophageal cancer and has been linked to p53 genetics. The p53 gene family regulates cell-cycle arrest, apoptosis and DNA damage repair. A recently identified ribonucleotide reductase, p53R2, is directly regulated by p53 in the supply of nu...
The inactivation of bacteriophage HP1c1 by X rays in a complex medium was found to be exponential, with a D0 (the X-ray exposure necessary to reduce the survival of the phage to 37%) of approximately 90 kR. Analysis of results of sucrose sedimentation of DNA from X-irradiated whole phage showed that the D0 for intactness of single strands was about 105kR, and for intactness of double strands, i...
BACKGROUND Radiotherapy may represent an alternative treatment modality for cystic echinococcosis (CE), but there is no adequate evidence for it up to now. In this study, we aim to investigate the parasiticidal effects of X-ray on the metacestodes of Echinococcus granulosus in vitro. METHODS Protoscoleces obtained from sheep naturally infected with CE were cultivated in RPMI 1640 medium conta...
Low-energy X-rays induce Auger cascades by photoelectric absorption in iodine present in the DNA of cells labeled with 5-iodo-2'-deoxyuridine (IUdR). This photoactivation therapy results in enhanced cellular sensitivity to radiation which reaches its maximum with 50 keV photons. Synchrotron core facilities are the only way to generate such monochromatic beams. However, these structures are not ...
We studied the relation between initial DNA double-strand breaks (DNA-DSB) and the rejoining kinetics of the strand breaks, as well as the OER (oxygen enhancement ratio) after low- and high-LET (linear energy transfer) radiations. CHO cells were exposed to 200 kVp X-rays or 80 keV/microm carbon ions under oxic and hypoxic conditions. DNA-DSB in the cells were analyzed by a static-field gel elec...
We present a method for the calculation of the effects of external irradiation on the geometrical shape of the secondary in a close binary containing a compact star, the source of the radiation, and a normal companion star, where we include the possibility of shadowing by an accretion disc. The model is based on a simple modification of the standard Roche binary potential in which the radiation...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید