Permanent inflation of detachable balloons with a low-viscosity, hydrophilic polymerizing system

A polymer system was developed for use in permanent inflation of detachable balloons, to avoid long-term reliance on the integrity of balloon shells or valve mechanisms. This system is based on 2-hydroxy-ethyl methacrylate (HEMA) as the monomer, in combination with a cross-linking agent and a water-soluble curing system. The low-viscosity, hydrophilic mixture can be exchanged through a small-bore catheter into a detachable balloon and polymerizes in 40-60 minutes at body temperature. Partially polymerized HEMA can cause vascular occlusion; hence, careful timing of balloon detachment is required. The evolution of the radiographic appearance of HEMA-filled balloons is predictable. The balloons remain radiopaque on plain radiographs as long as the balloon shell and valve mechanisms are competent. After rupture of the shell or failure of the valve mechanism, the balloons become invisible on plain radiographs but remain hyperattenuating on computed tomography scans.     

Problems of Psychological Monitoring in Astronaut Training

在进行职业训练时，对受训者的心理变化趋势进行监视是必要的。航天员心理因素的发展水平可通过心理测试来检测，以便能对其重要的心理指标进行评价，并给出综合评价。文中列出应进行测试的心理指标，并根据大量的样本统计给出了经验加权因子。测试结果的积累可以预测航天员将来飞行任务中处理复杂问题的能力，并能帮助改进训练过程及暴露缺点。     

重组腺病毒bcl-xs基因对人卵巢癌裸鼠移植瘤作用的研究

目的 观察重组腺病毒bcl-xs基因（adv-bcl-xs基因,简称bcl-xs基因）对人卵巢癌裸鼠移植瘤的生长抑制和荷瘤裸鼠生存率的影响。为卵巢癌的基因治疗提供实验基础。方法 采用以复制缺陷型腺病毒bcl-xs基础感染的人胚肾细胞,使bcl-xs基因对NUTU-19细胞的生长抑制作用并检测其病毒滴度后,将bxl-xs基因导入人卵巢癌裸鼠移植瘤中,观察bcl-xs基因对腹水的生长抑制作用,计算裸鼠的生存时间,并观察bcl-xs基因对裸鼠全身和局部的毒副作用。电镜观察bcl-xs基因的病毒颗粒,以免疫细胞化学染色测定bcl-xs基因表达情况。结果 bcl-xs基因可在人胚肾细胞内扩增,对NUTU-19细胞有抑制和杀伤作用。并在裸鼠体内呈过度表达,使裸鼠腹水形成的时间由5-10d延长至11-23d,裸鼠平均生存时间由24d延长至39d,bcl-xs基因对裸鼠全身和局部无明显毒副作用。结论 bcl-xs基因导入人卵巢癌裸鼠移植肿瘤,能延缓腹水形成,延长裸鼠的生存时间,为卵巢癌的基因治疗提供了一种新方法。     

Changes in the occurrence of sister chromatid exchange and chromosome aberrations in bone marrow cells of mice after administration of chromium with drinking water

Through taking into account frequency of sister chromatid metabolisms and chromosome aberrations in bone marrow cells of animals it is demonstrated that under long-term body intake chromium in a wide range of doses can produce mutagenic effect. When assessing chromium mutagenic effect in vivo it is also shown that the test on sister chromatid metabolism is more sensitive than the test on chromosome aberrations in bone marrow cells.