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小鼠脾淋巴细胞辐射死亡与凋记之间的关系 总被引:10,自引:0,他引:10
探讨细胞凋亡在小鼠脾脏辐射损伤与重建中的作用及其机制,为急性放射病的防治提供依据。用原位末端标记、DNA电泳和免疫组化技术观察经2 ̄8Gy不同剂量γ射线整体照射后,小鼠脾脏淋巴细胞凋亡的动态变化过程和Bax、Bcl-2蛋白在其中的作用。结果表明,(1)照射后早期淋巴细胞凋亡率迅速增加,如6Gy照射后4h和1d凋亡率分别为对照值的4.9和9.7倍;凋亡率还随照射剂量的增加而迅速升高;照射后8h当照射 相似文献
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报道了在妊娠期以单次腹腔注入氚水,宫内受到累积剂量分别为0、0.05、0.10和0.30Gyβ射丝辐射后,对雄性仔鼠行为、学习及记忆能力的影响。研究发现0.10Gy以上剂量组对旷场行为,跳台学习及记忆能力、食物迷宫、水迷宫和孔板探究等多项测试指标均有影响,表现为早期兴奋性增强、晚期抑制及学习记忆能力的减退。结果提示阈剂量大约在0.05和0.10 Gy之间。 相似文献
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Neuberger T Greiser A Nahrendorf M Jakob PM Faber C Webb AG 《Magma (New York, N.Y.)》2004,17(3-6):196-200
The mouse has become an important animal model for human cardiac disease, and the development of techniques for non-invasive imaging of the mouse heart in vivo is, therefore, of great potential interest. Previous magnetic resonance imaging studies have concentrated on pathologically induced changes in cardiac structure and dynamics by acquiring proton images. Further information can be gained by studying cardiac function and physiology using other nuclei, for example, sodium. Sodium imaging of such a small structure presents considerable technical challenges. In this work we show the first sodium images of the mouse heart, with an isotropic spatial resolution of 1 × 1 × 1 mm, acquired in a time of 1.5 h. The ventricles, septum and myocardium are readily distinguishable in these images, which were acquired through the combination of 3D density-weighted chemical shift imaging, optimized instrumentation, and a high magnetic field strength (17.6 T). Measurements of the myocardial:blood sodium concentration in the left and right ventricles agree well with theoretical values. 相似文献
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Using a computer keyboard with the forearms unsupported has been proposed as a causal factor for neck/shoulder and arm/hand diagnoses. Recent laboratory and field studies have demonstrated that forearm support might be preferable to working in the traditional "floating" posture. The aim of this study was to determine whether providing forearm support when using a normal computer workstation would decrease musculoskeletal discomfort in intensive computer users in a call centre. A randomised controlled study (n = 59), of 6 weeks duration was conducted. Thirty participants (Group 1) were allocated to forearm support using the desk surface with the remainder (Group 2) acting as a control group. At 6 weeks, the control group was also set up with forearm support. Both groups were then monitored for another 6 weeks. Questionnaires were used at 1, 6 and 12 weeks to obtain information about discomfort, workstation setup, working posture and comfort. Nine participants (Group 1 n = 6, Group 2 n = 3) withdrew within a week of commencing forearm support either due to discomfort or difficulty in maintaining the posture. At 6 weeks, the group using forearm support generated significantly fewer reports of discomfort in the neck and back, although the difference between the groups was not statistically significant. At 12 weeks, there were fewer reports of neck, back and wrist discomfort when preintervention discomfort was compared with post intervention discomfort. These findings indicate that for the majority of users, forearm support may be preferable to the "floating" posture implicit in current guidelines for computer workstation setup. 相似文献
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《Ergonomics》2012,55(13-14):1320-1331
Among many important attributes, designers often seek to create products that are comfortable both in the sense of avoiding discomfort and providing a positive sense of comfort. Another way of looking at the design of hand-held products is to consider what attributes make a product enjoyable to touch, rather than just comfortable or uncomfortable. A series of focus discussions investigated the qualities of objects that are enjoyable to touch. Persons were asked to bring in one or two objects that said to them, ‘Touch me’ and ‘Keep touching me’. Discussion with the participants discerned their motivations for selecting the touchable objects. Observations noted the objects' sizes, weights, shapes, surfaces, and colours. This research about qualities of touchable objects influenced the designs of new designs of trackballs for computer navigation. Further hypothesis supposes that the attributes of touchable objects are based on human experience over time with nature. 相似文献
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脂质体包裹猪白细胞介素6基因对猪带绦虫抗原基因免疫小鼠的影响 总被引:3,自引:0,他引:3
比较研究了BALb/c小鼠分别肌肉注射猪带绦虫抗原基因VTS76、猪白细胞介素6(VPIL-6)联合VTS76及其阳离子脂质体包裹质粒等5个处理的免疫效应。结果表明,VTS76联合VPIL-6共注射小鼠的IgG含量和抗体滴度,脾细胞增殖反应和IL-2诱生活性以及免疫细胞数量,均比注射VTS76的显著增强。经阳离子脂质体包裹的VTS76+VPIL-6在减少质粒用量80%时,免疫应答水平仍显著高于脂质体包裹VTS76,且明显高于VTS76+VPIL-6,证明VPIL-6能显著增强基因疫苗(VTS76)免疫小鼠的免疫应答。 相似文献