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71.
Exposure of rats to radiation in a dose of 1 Gy changes sensitivity of chromatin in the cerebral cortex cells to the action of DNAase 1, which promotes an increase of the DNA hydrolysis level and content of dissolved chromatin fractions. A day after irradiation the chromatin structure restores only partially and then (7-30 days after irradiation) it passes into a new, less compact state. The irradiation changes the chromatin ability to aggregation in the presence of Mg2+ and spermidine. 相似文献
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We performed simultaneous fasting and fed antroduodenal manometry and EGG in 25 children with functional bowel disorders. Three patients (12%) had an uninterpretable EGG. The manometric studies showed severe neuropathy in six patients; milder neuropathic changes in five patients; postprandial hypomotility in one patient; myopathy in four patients, and normal motility in the remaining six patients. The percentage of tachygastria time (frequency > 3.5 cycles/min) was higher in the patiens with mild (44.1 +/- 15.8%) and severe (48 +/- 19.1%) neuropathy than in the patients with myopathy (20 +/- 16.2%, P < 0.05) or with normal motility (23 +/- 13.3%, P < 0.05). There was a considerable overlap in the percentage of tachygastria and total arrhythmia time among the different study groups. The ratio of post- to preprandial power was significantly higher (2.5 +/- 0.07) in children with normal motility than in the other patients groups. Every child with total arrhythmia time < 35% and a ratio of post- to preprandial power > 2.4 had normal manometry. In summary, EGG differentiated groups of children with normal manometry from others with neuropathic or myopathic changes, but in a minority of patients the study was not interpretable and there was overlap in EGG results between children with normal and abnormal manometry. 相似文献
73.
In this work was investigated the effect of the addition of barium titanate (BaTiO3) on electrical properties of two chemically recyclable thermosets, polyhemiaminal (PHA) and polyhexahydro‐s‐triazine (PHT), both fabricated from 4,4′‐oxydianiline (ODA), an ether derivative of aniline and paraformaldehyde. Thermal and mechanical properties as well as chemical recyclability of the two polymers and their nanocomposites/nanodielectrics were also investigated. In addition, a quantitative analysis was conducted of the nanoparticle dispersion in the PHA‐/PHT‐based BaTiO3‐containing nanocomposites using transmission electron microscopy imaging and the nearest‐neighbor distance index and this index was used to analyze the investigated properties in connection with the proper mechanisms. Regarding the electrical properties for both neat polymers, conductivity values of the order of 10?8 S m?1 at 100 Hz were observed and dielectric constant values close to 2.80 for both polymers at 1 kHz. The addition of 0.5 wt% of BaTiO3 ferroelectric nanoparticles increased by about 44% the dielectric constant (1 kHz) and conductivity (102 Hz) of the PHA‐based nanocomposite. PHA and PHT exhibited glass transition temperature (Tg) values in the range 125–180 °C. An increase of 7 °C in Tg was observed after the incorporation of 0.5 wt% of BaTiO3 into PHA. Concerning the mechanical properties, values in the range 4.00–4.45 GPa for reduced modulus and 0.30–0.43 GPa for nanohardness for PHA and PHT polymers were observed. Independently of filler content or polymer matrix, both mechanical properties were enhanced after the addition of BaTiO3. The chemical recycling of PHA/PHT and all nanocomposites in the initial ODA reagent after sulfuric acid treatment was successfully characterized using the NMR and Fourier transform infrared spectroscopic techniques. © 2018 Society of Chemical Industry 相似文献
74.
A Golay I Hagon D Painot P Rouget AF Allaz Y Morel J Nicolet M Archinard 《Canadian Metallurgical Quarterly》1997,31(2):103-112
The ability of lonidamine (LND), an energolytic derivative of indazole-carboxylic acid, to modulate the cytotoxic activity of cisplatin (CDDP) and epidoxorubicin (EPI), singly or in combination, was investigated in two human breast cancer cell lines (MCF7 and T47D). A 72-hr post-incubation with a non-cytotoxic concentration of LND (75 microM) increased the activity of a 1-hr CDDP treatment as well as that of a 1 to 16-hr EPI treatment. A different pattern of interaction among the drugs and modulator was observed as a function of the sequence of drug treatment. Specifically, supra-additive or additive effects of the combination were obtained in the two cell lines according to the different treatment schemes. In particular, the maximum potentiation was observed in MCF7 cells simultaneously exposed to CDDP, EPI and LND for 1 hr and then post-incubated with LND for 72 hr, and in T47 first exposed to EPI and LND, then to CDDP and LND, and finally post-incubated with LND. Flow cytometric analysis of MCF7 cell distribution in the different cycle phases showed that combined treatment with EPI/CDDP/LND was able to stabilize cell cycle perturbations (mainly G2M accumulation) induced by individual agents. The ability of LND to potentiate CDDP and EPI cytotoxicity, and the consideration that LND causes side effects different from those caused by alkylating agents and anthracyclines, make this compound an attractive candidate for multidrug combination therapy in breast cancer. 相似文献
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This paper discusses the issues of providing an empirically validated, manual-based-treatment when viewed from the perspective of a practicing clinical psychologist. The trend for empirically proven treatment is reviewed briefly, and initial data are provided illustrating a manual-based-treatment for post-traumatic stress disorder (PTSD) following a motor vehicle accident. The relatively brief (9-12 session) psychological treatment was effective in reducing PTSD symptoms as measured on the Clinician Administered PTSD Scale, for all 10 subjects. The results are discussed form the practicing clinician's perspective: generalization to a clinical population, ethical concerns of limited treatment goals, individually tailored vs standardized treatments in clinical practice, concerns for co-morbid conditions, and how this type of study might impact on practice in an era of managed health care. Issues of incorporating manual based treatments into clinical practice are discussed, with consideration of gains, the limits and the constraints this would bring to the practice of psychology. 相似文献
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Haemagglutination of purified F42 fimbriae was found to be inhibited by N-acetyl-galactosamine. Purified F42 fimbrial adhesin reacted with distinct membrane components from chicken erythrocytes (35, 37 and 40 kDa) in immunoblot analysis, suggesting that the binding occurred to proteins or glycoproteins. 相似文献