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31.
Enterocytes die during high‐dose radiation exposure in radiation accidents. The modality of cell death has a profound effect on the therapeutic response. The ilea from mice with 15 Gy total body irradiation (TBI) were drawn, morphological features observed by hematoxylin and eosin staining and transmission electron micrographs. The biochemical features of mouse ileum presented with the structure were cleaved Caspase‐3 (apoptosis marker), Light Chain 3 (LC3)‐I's conversion to LC3‐II (autophagy marker) and high mobility group box chromosomal protein 1's secretion (necrosis marker). Then, the autophagy inhibitor (3‐methyladenine), caspase inhibitor (Z‐VAD‐FMK) or necrosis inhibitor (necrostatin) was used to prevent death. Apoptosis, autophagy and necrosis were all appeared in the ileum, but necrosis had the biggest size; the use of 3‐methyladenine and Z‐VAD‐FMK prolong one day's life of the mice after 15 Gy TBI, necrostatin significantly extended the lifespan of 15 Gy irradiated mice (p < 0.05). The results suggest that the death of enterocytes could not be classified into one type of cell death but rather as ‘mixed death.’ Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
32.
Little is known about effects of dietary glutamine supplementation on specific and general defense responses in a vaccine-immunized animal model. Thus, this study determined roles for dietary glutamine supplementation in specific and general defense responses in mice immunized with inactivated Pasteurella multocida vaccine. The measured variables included: (1) the production of pathogen-specific antibodies; (2) mRNA levels for pro-inflammatory cytokines, toll-like receptors and anti-oxidative factors; and (3) the distribution of P. multocida in tissues and the expression of its major virulence factors in vivo. Dietary supplementation with 0.5 % glutamine had a better protective role than 1 or 2 % glutamine against P. multocida infection in vaccine-immunized mice, at least partly resulting from its effects in modulation of general defense responses. Dietary glutamine supplementation had little effects on the production of P. multocida-specific antibodies. Compared to the non-supplemented group, dietary supplementation with 0.5 % glutamine had no effect on bacterial burden in vivo but decreased the expression of major virulence factors in the spleen. Collectively, supplementing 0.5 % glutamine to a conventional diet provides benefits in vaccine-immunized mice by enhancing general defense responses and decreasing expression of specific virulence factors.  相似文献   
33.
Heat shock protein 22 (HSP22) is an important member of small heat shock protein (sHSP) subfamily which plays a key role in the process of protecting cells, facilitating the folding of nascent peptides, and responding to stress. In the present study, the cDNA of HSP22 was cloned from Argopecten irradians (designated as AiHSP22) by rapid amplification cDNA end (RACE) based on the expressed sequence tags (ESTs). The full-length cDNA of AiHSP22 was of 1,112 bp, with an open reading frame of 588 bp encoding a polypeptide of 195 amino acids. The deduced amino acid sequence of AiHSP22 showed high similarity to previously identified HSP22s. The expression patterns of AiHSP22 mRNA in different tissues and in haemocytes of scallops exposed to Cd2+, Pb2+ or Cu2+ were investigated by real-time quantitative RT-PCR. The mRNA of AiHSP22 was constitutively expressed in all examined tissues, including haemocyte, muscle, kidney, gonad, gill and heart. The expression level in heart and muscle was higher than that in other tissues. The mRNA level of AiHSP22 in haemocytes was up-regulated after a 10 days exposure of scallops to Cu2+, Pb2+ and Cd2+. However, the expression of AiHSP22 did not increase linearly along with the rise of heavy metal concentration. Different concentrations of the same metal resulted in different effects on AiHSP22 expression. The sensitive response of AiHSP22 to Cu2+, Pb2+ and Cd2+ stress indicated that it could be developed as an indicator of exposure to heavy metals for the pollution monitoring programs in aquatic environment.  相似文献   
34.
目的探讨老年患者术后应用自控镇痛技术对康复治疗的临床护理。方法将304例患者随机分成两组,治疗组给予术后自控镇痛,对照组给予阿片类或吗啡类止痛,分别对镇痛效果、胃肠道恢复时间、尿潴留发生率、睡眠情绪满意率几方面进行对比。结果两组间在镇痛评分(VAS)和睡眠情绪满意率存在统计学差异(P〈0.05);而术后胃肠道恢复时间、尿潴留发生率两组间差异无统计学意义(P〉0.05)。结论良好的自控镇痛技术能提高老年患者术后镇痛质量和睡眠情绪满意度。何丽娟,汪凤梅,余丽花  相似文献   
35.
Maize is one of the major cultivated crops of China, having a central role in ensuring the food security of the country. There has been a significant increase in studies of maize under interactive effects of elevated CO2 concentration ([CO2]) and other factors, yet the interactive effects of elevated [CO2] and increasing precipitation on maize has remained unclear. In this study, a manipulative experiment in Jinzhou, Liaoning province, Northeast China was performed so as to obtain reliable results concerning the later effects. The Open Top Chambers (OTCs) experiment was designed to control contrasting [CO2] i.e., 390, 450 and 550 µmol·mol−1, and the experiment with 15% increasing precipitation levels was also set based on the average monthly precipitation of 5–9 month from 1981 to 2010 and controlled by irrigation. Thus, six treatments, i.e. C550W+15%, C550W0, C450W+15%, C450W0, C390W+15% and C390W0 were included in this study. The results showed that the irrigation under elevated [CO2] levels increased the leaf net photosynthetic rate (P n) and intercellular CO2 concentration (C i) of maize. Similarly, the stomatal conductance (G s) and transpiration rate (T r) decreased with elevated [CO2], but irrigation have a positive effect on increased of them at each [CO2] level, resulting in the water use efficiency (WUE) higher in natural precipitation treatment than irrigation treatment at elevated [CO2] levels. Irradiance-response parameters, e.g., maximum net photosynthetic rate (P nmax) and light saturation points (LSP) were increased under elevated [CO2] and irrigation, and dark respiration (R d) was increased as well. The growth characteristics, e.g., plant height, leaf area and aboveground biomass were enhanced, resulting in an improved of yield and ear characteristics except axle diameter. The study concluded by reporting that, future elevated [CO2] may favor to maize when coupled with increasing amount of precipitation in Northeast China.  相似文献   
36.
The aim of the study is to investigate the radioprotective effect of polysaccharide extract from Sipunculus nudus (SNP). Beagle dogs were randomly divided into the following six groups. Group-1: Un-treated and un-irradiated controls. Group-2: Exposed to a single acute dose of 2 Gy γ-radiation alone. Groups-3, 4 and 5: Oral administration of SNP at 50, 100 or 200 mg/kg body weight once a day for 7 days followed by a single acute whole body exposure to 2 Gy γ-radiation. The same doses of SNP were administered for further 27 days. Group-6: Positive controls treated with 1.6 mg/kg Nilestriol by gavage after radiation. Blood parameters including white/red cells and platelet counts, as well as hemoglobin level, were assessed every other day for 34 days (7 days before and 27 days of experiment). Serum separated from aliquots of the same blood sample was used to estimate enzyme activity of antioxidant superoxide-dismutase, and to determine levels of free radical, nitric oxide, hydroxyl and superoxide anion. At the end of the experiment, all dogs were euthanized to weigh the organs for organ co-efficient calculation. Pathological changes were assessed in the bone marrow. The results showed that the dogs exposed to γ-radiation alone exhibited a typical hematopoietic syndrome. In contrast, at the end of 27 days experiment, dogs received oral administration of SNP+γ-radiation showed: (i) a much improved blood picture as indicated by shorter duration of leucopenia, neutropenia, thrombocytopenia (platelet counts), as well as hemoglobin levels, (ii) significantly improved hematopoietic activity in the bone marrow, (iii) substantial decrease in nitric oxide levels, and notable increase in activity of antioxidant superoxide dismutase. The results suggested that oral administration of SNP in Beagle dogs was effective in facilitating the recovery of hematopoietic bone marrow damage induced by γ-radiation.  相似文献   
37.
目的拟将尼罗红包裹入纳米制剂中,利用其荧光特性来考察纳米制剂在荷瘤鼠体内的肿瘤靶向性与组织分布情况。方法采用CCK-8法检测尼罗红纳米乳[NRNE(O)]对H1688的细胞毒性。建立BALB/c裸鼠肺癌模型,灌胃给予尼罗红混悬液(NRS)及NRNE(O),通过小动物活体成像系统观察其在荷瘤裸鼠中荧光强度的动态分布情况。结果 NRNE(O)具有较低的细胞毒性和良好的生物相容性,并且在体内的吸收量及肿瘤部位的蓄积量均高于NRS;NR在纳米制剂中能快速、稳定、清晰地反映纳米制剂在小鼠体内的动态分布情况。结论本研究中制备的NRNE(O)的稳定性好,为尼罗红作为示踪剂应用于纳米制剂在动物体内的研究提供了重要的研究手段。  相似文献   
38.
All‐solid‐state on‐chip SiC supercapacitors (SCs) based on free‐standing SiC nanowire arrays (NWAs) are reported. In comparison to the widely used technique based on the interdigitated fingers, the present strategy can be much more facile for constructing on‐chip SCs devices, which is directly sandwiched with a solid electrolyte layer between two pieces of SiC NWAs film without any substrate. The mass loading of active materials of on‐chip SiC SCs can be up to ≈5.6 mg cm?2, and the total device thickness is limited in ≈40 µm. The specific area energy and power densities of the SCs device reach 5.24 µWh cm?2 and 11.2 mW cm?2, and their specific volume energy and power densities run up to 1.31 mWh cm–3 and 2.8 W cm?3, respectively, which are two orders of magnitude higher than those of state‐of‐the‐art SiC‐based SCs, and also much higher than those of other solid‐state carbon‐based SCs ever reported. Furthermore, such on‐chip SCs exhibit superior rate capability and robust stability with over 94% capacitance retention after 10 000 cycles at a scan rate of 100 mV s?1, representing their high performance in all merits.  相似文献   
39.
中药复方“保康”的抗氧化与清除自由基作用   总被引:1,自引:0,他引:1  
分别彩改良的IBA分光光度法和肾上腺素自氧化法研究中药复方“保康”对辐射所致小鼠某些组织中LPO含量及SOD水平变化的影响;采用ESR方法研究“保康”对羟自由基的清除作用。结果发现,“保康”能明显抑制辐照所致LPO含量增高,并能提高组织中SOD水平;ESR研究表明“保康”对羟自由基具有良好的清除作用。  相似文献   
40.
哺乳动物体细胞克隆技术在动物育种及珍稀动物保护领域具有极其广阔的应用前景,但极低的成功率限制了这项技术的应用.相关学者从不同方面进行了研究,试图提高体细胞克隆技术的成功率.综述了近年来哺乳动物体细胞克隆技术的研究进展,为其相关研究提供必要的参考.  相似文献   
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