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121.
Chemo-radiotherapy, which combines chemotherapy with radiotherapy, has been clinically practiced since the 1970s, and various anticancer drugs have been shown to have a synergistic effect when used in combination with radiotherapy. In particular, cisplatin (CDDP), which is often the cornerstone of multi-drug combination cancer therapies, is highly versatile and frequently used in combination with radiotherapy for the treatment of many cancers. Therefore, the mechanisms underlying the synergistic effect of CDDP and radiotherapy have been widely investigated, although no definitive conclusions have been reached. We present a review of the combined use of CDDP and radiotherapy, including the latest findings, and propose a mechanism that could explain their synergistic effects. Our hypothesis involves the concepts of overlap and complementation. “Overlap” refers to the overlapping reactions of CDDP and radiation-induced excessive oxidative loading, which lead to accumulating damage to cell components, mostly within the cytoplasm. “Complementation” refers to the complementary functions of CDDP and radiation that lead to DNA damage, primarily in the nucleus. In fact, the two concepts are inseparable, but conceptualizing them separately will help us understand the mechanism underlying the synergism between radiation therapy and other anticancer drugs, and help us to design future radiosensitizers.  相似文献   
122.
Computational Visual Media - In many-light rendering, a variety of visual and illumination effects, including anti-aliasing, depth of field, volumetric scattering, and subsurface scattering, are...  相似文献   
123.
Effects of background noise on click-evoked otoacoustic emissions   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate the effect of increased levels of background noise on click-evoked otoacoustic emission (CEOAE) recordings and to compare the effectiveness of the default CEOAE program with the QuickScreen CEOAE program in increased levels of noise, using an Otodynamics ILO88 recording device. DESIGN: The right ears of 40 young adult women with normal hearing were assessed using CEOAEs under four different noise conditions and with two different methods of data collection. The noise conditions were in quiet, 50 dB A, 55 dB A, and 60 dB A of white noise. Data were collected at each noise level in the default mode and also using the ILO88 QuickScreen program. RESULTS: There was a significant change in a number of important CEOAE output parameters with increased noise. In the default mode, mean whole wave reproducibility was 89.2% in quiet but declined to 85% with 50 dB A of white noise, 65% at 55 dB A and 20% at 60 dB A. The QuickScreen program proved more robust to the effects of noise than the default. In that mode, mean whole wave reproducibility was 91.7% in quiet, 92.5% with 50 dB A of white noise, 82.5% at 55 dB A and 45% at 60 dB A. CONCLUSIONS: The findings of the study indicate ambient noise levels for accurate CEOAE recording should not exceed 50 to 55 dB A of noise and alternatives to the default program should be considered in non-sound-treated situations.  相似文献   
124.
Valence band offsets at [100]-oriented heterojunctions between tensile-strained GaASj1−xPx and unstrained GaAs are studied experimentally and theoretically. Light-hole (LH) and heavy-hole (HH) offsets are first extracted from the well-width dependence of valence subband splittings observed in luminescence spectra of tensile-strained GaAs1−xPx/GaAs quantum wells of various compositions (x = 0.06,0.09, and 0.19). This data is then combined with results from two other laboratories, yielding a set of 30 independent experimental offset values for junctions with compositions throughout the range 0.06≤x ≤0.32. The data are found to be highly consistent, with linear fits δELH = −140x (meV) and δEHH= −401x (meV) describing the measured offsets to within less than 5 meV on average. Experimental results are then compared with theoretical predictions for the GaAs1−x Px/GaAs system obtained from a tight-binding model for strained heterojunctions. Predictions from the tight-binding calculations are found to lie within experimental scatter for the LH offsets, which define the valence band edge in these heterostructures, while magnitudes of the tight-binding HH offsets exceed measured values by ~20% on average.  相似文献   
125.
The effects of various types of alginic acid consisting of L-guluronic acids (G) and D-mannuronic acids (M) on hyaluronidase and mast cell degranulation were examined. Alginic acid with an M/G ratio of 1.0 exhibited the strongest inhibition of both activities, the higher molecular weight alginic acids of 150 to 370 kDa being preferable in both cases. Esterification of the carboxyl residue enhanced the latter activity.  相似文献   
126.
We propose a mesoscopic version of the thermodynamic equilibration condition for open systems, which is applied to some simple cases to obtain physical expressions of higher order temperatures.  相似文献   
127.
128.
A prototype 13.3‐inch 8k4k 664‐ppi high‐resolution foldable organic light emitting diode display is constructed. C‐axis aligned a‐b‐plane‐anchored crystal In–Ga–Zn oxide field effect transistors designed using a 1.5‐µm rule process are used in the backplane. Each pixel circuit has three transistors and one capacitor, and an external circuit is used to correct pixel current.  相似文献   
129.
High pixel per inch and high‐resolution micro‐LED displays are attracting more and more attentions. The increasing pixel number requires a large amount of bonding pads and brings huge difficulties to micro‐LED system design and lowers power efficiency as well. It is urgent to integrate row and column driving circuits onto the micro‐LED panel. Here, we report a fully integrated active matrix programmable micro‐LED system on panel (SoP) with ultraviolet and blue emission wavelengths. The micro‐LED SoP has a resolution of 60 × 60 and pixel pitch of 70 μm. The micro‐LED SoP was achieved by integrating micro‐LED arrays with silicon‐based p‐channel metal‐oxide semiconductor driving panel using fine‐toned flip‐chip bonding technology. With fully integrated scan and data circuits, the number of bonding pads was greatly reduced from 136 to 28, and large amount of metal interconnection lines were saved. The micro‐LED SoP panel was mounted on a periphery driving board, and representative characters were displayed successfully.  相似文献   
130.
Positive and negative photosensitive polyimides developable with basic aqueous solutions are reported. The results consist of poly amic acids and naphthoquinone diazides in which sulfonate groups have to be substituted at 4-position. It depends on the naphthoquinone structures whether positive or negative patterns are obtained. In order to fabricate resist patterns, High-Temperature-Post-Exposure-Process (HIT-PEB) must be utilized. The reaction mechanisms are also discussed. © 1992 John Wiley & Sons, Inc.  相似文献   
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