卫星生物搭载舱的辐射剂量测量及蚕卵生物叠试验

本文利用LiF热释光剂量计对我国生物搭载舱内外宇宙辐射剂量作了监测研究。经过八天的近地轨道飞行,舱内累积辐射剂量约为0.53±0.04mGy,平均日剂量约为0.07mGy/d。舱内辐射剂量主要是能量为50MeV 以上的高能质子形成的。这一剂量水平比地面高27倍,但未超过最大允许剂量,在评价空间生物效应时可作参考。本文还讨论了屏蔽厚度的影响,中子对剂量的贡献及舱内平均日剂量与轨道高度的关系。在生物舱内放置了CR-39塑料核径迹探测器与蚕卵组成的生物叠进行宇宙线重粒子及其生物效应的研究。为判定蚕卵样品是否被重粒子所击中,解决了重粒子射入蚕卵的径迹定位技术。试验表明,生物叠中被重粒子击中的蚕卵孵化率略高于未被击中的蚕卵孵化率,虽因样本量少不能满足统计学要求,但其趋势与国外报导的某些试验结果相一致。     

载人航天飞行空间辐射研究进展

空间辐射是载人航天长期飞行及深空探测面临的最重要的环境因素之一。本文系统介绍了近地轨道飞行及载人登月、深空探测任务中空间辐射的时空分布特征,对当前空间辐射生物效应的研究热点(致癌、中枢神经系统影响、退行性变、辐射综合症)、空间辐射剂量测量、风险评估及防护技术的研究现状及进展进行综述,并提出了后续发展方向建议。     

空间辐射生物学效应及生物防护措施研究进展

目的 综述空间辐射的生物学效应及生物防护措施的研究进展,探讨各种生物防护途径的作用机制及未来的发展方向. 资料来源与选择国外该领域的研究及论著资料引用引用文献资料39篇. 资料综合空间辐射粒子尤其是高能重离子对人体细胞及组织器官有严重危害,某些药物及活性物可以通过抗自由基、调节免疫、调节细胞分裂周期等途径对抗辐射损伤效应. 结论 生物防护方法可以有效降低空间辐射带来的伤害,包括辐射诱导引起的癌症、免疫抑制以及神经损伤等不利效应.     

电离辐射与生物组织作用的径迹结构研究方法

分析了电离辐射与人体组织相互作用的微观物理机制，确定了电离辐射微剂量学在研究辐射生物效应过程中的重要地位，指出径迹结构研究方法用于计算电离辐射粒子在人体组织中能量沉积时的可行性。     

α粒子照射体外细胞的生物效应研究的现状与展望

α粒子照射体外细胞的生物效应研究的现状与展望龚诒芬自１９９５年Ｅｌｋｉｎｄ应用２１０Ｐｏα放射源研究α粒子致酵母细胞的辐射敏感性以来，许多放射生物学和放射毒理学家在这个领域里进行了卓有成效的工作。在研究初期，α粒子作为一种高ＬＥＴ辐射源，用于体外细胞...     

重离子辐射的细胞突变效应

重离子治癌作为一种新的疗法应用越来越广泛，同时，随着宇航事业的发展，有关重离子辐射的生物效应研究日益增多。本文对重离子辐射所致细胞的突变效应与其各种物理参数如粒子注量、突变截面的关系及重离子辐射致突变的相对生物效应和特点等作了扼要介绍     

电离辐射与生物组织作用的径迹结构研究方法

分析了电离辐射与人体组织相互作用的微观物理机制，确定了电离辐射微剂量学在研究辐射生物效应过程中的重要地位，指出径迹结构研究方法用于计算电离辐射粒子在人体组织中能量沉积时的可行性，并利用程序ESLOW3．1和MOCA15进行了相关物理参数的精确计算工作。     

高能重离子的生物学效应初探

为研究高能重离子对高等植物种子的影响，用核径迹探测器与药用植物干种子复合制成生物叠的方法，在卫星搭载实验中，初步探查了空间环境对莨菪和藿香的生物学效应，发现单纯失重因素对当年栽培的植株无显著影响，但被高能重离子击中的种子经３个月储存后，其栽培的植株长势有明显增快，开花和结实时间也早于对照组，但染色体凶有损伤或变异。确认这种方法能较精细地鉴别空间环境中持续失重和高能重离子击中两个因素的生物学效应，是     

中倾角近地轨道载人航天辐射危险性分析

为了解５００ｋｍ以下，倾角为４０°～５０°的近地轨道载人航天辐射危险性。按照已知太阳质子事件参数的轨道飞行器舱内辐射剂量实际测量结果对其他大事件进行估计，结果表明，迄今为止的太阳质子事件不会对如此轨道载人飞行的辐射安全构成威胁。     

中国首次小鼠的轨道飞行实验

利用我国返回式科学实验卫星，搭载装有２只小白鼠的生物舱，在近地球轨道上飞行８ｄ，初步观察飞行因素对小白鼠的影响。实验前对动物进行选训，挑选出体格健壮、对环境适应能力强的２只昆明种、雄性、成年小白鼠进行飞行。飞行前，对舱内仪器、设备和动物均进行消毒检疫处理。小白鼠在轨道上存活了５．４ｄ，由於失重原因，飞行后小鼠的骨形成率有降低趋势，力学特性无明显变化；小鼠脑、肺等组织残留了动物死亡前发生的血管性变化     

俄生物卫星的家蚕搭载飞行实验

在俄罗斯第１０颗生物卫星上，家蚕滞育卵，非滞育卵，熟蚕，蚕蛹，蚕茧和蚕蛾完成了１２天的空间飞行和吐丝结茧，交配产卵，胚胎发育，化蛹化蛾等一系列行为和变态过程，发现飞行组与对照组比较家蚕发育过程缩短；滞育卵在飞行中孵化率提高；在飞行中产卵所发育的家蚕的蚕丝质量有提高的趋势，并观察到三个飞行品种家蚕出现明显的形态学变异现象。     

"北京-纽约"极地航线空勤人员所受光子、中子有效辐射剂量测量分析

目的 研究极地航线空勤人员(包括飞行员和空乘人员)所受宇宙辐射剂量,以评价其是否超过国家标准,确保空勤人员健康,保障飞行安全. 方法 采用外照射全身个人剂量监测胸章剂量计,对典型极地航线(北京-纽约)空勤人员(飞行员6名、空乘人员12名)的个人辐射剂量进行测定,以地面工作场所10个监测点所测得的辐射剂量作为对照组. 结果 极地航线飞行员组的年有效剂量为5.34 mSv/a,千小时有效剂量为(3.43±0.08)mSv/1000 h,极地航线空乘人员组的年有效剂量为6.06 mSv/a,千小时有效剂量为(2.94±0.14)mSv/1000 h,地面对照组分别为0.63 mSv/a及(0.07±0.02)mSv/1000 h,3组间差异均有统计学意义. 结论 极地航线飞行空勤人员的年有效剂量均未超过国家标准规定限值(20 mSv/a),极地飞行中宇宙射线辐射不会对空勤人员身体构成额外过量剂量,基本属正常航线飞行,不必产生心理恐慌. Abstract： Objective To measure the cumulative cosmic radiation dose of aircrew in polar flight and to assess whether the dose exceeds the national standard in order to ensure flight safety and their health. Methods Photoluminescence (OSL) dosimeter and CR-39 solid track detector were used to measure the cosmic radiation dose contributed by photon and neutron. The individual effective dose of pilots (6 persons) and stewards (12 persons), who were in the typical polar flight route (Beijing-New York), were measured and compared with the control group whose values were gathered from 10 monitors on ground site. Results The 1000 h effective dose from the groups of pilot and stewards was (3.43±0.08) mSv/1000 h and (2.94±0. 14) mSv/1000 h respectively comparing to (0.07±0. 02) mSv/1000 h gathered from ground sites. The statistic showed significant differences among these 3 groups. The annual effective does was then respectively summarized as 5. 34, 6.06 and 0.63 mSv/a corresponding to above groups. Conclusions The annual effective dose of aircrew's in polar flight does not exceed the limit of national standard (20 mSv/a). Such polar flight will not cause aircrew suffered from excessive cosmic radiation and it's not necessary to carry extra mental load.     

Effect of prehatching weightlessness on adult fish behavior in dynamic environments.

At 16-17 months of age, three groups of fish from the embryonated eggs in the ASTP killifish experiment were subjected to postflight tests consisting of rapidly changing environments. It was found that the group of fish with the least amount of development at orbital insertion (A-32) had a decreased rheotropism for both the moving background and the rotating water current tests when compared to ground control fish. Exposure to parabolic aircraft flight conditions revealed that the A-32 fish were less disoriented during zero gravity periods and were hypersensitive to high-gravity periods. These results suggested a modified vestibular competency due to a 9-d prehatching weightlessness exposure.     

飞行训练对飞行学员下丘脑-垂体-性腺轴功能的影响

目的 探讨飞行训练对飞行学员下丘脑－垂体－性腺轴功能的影响。方法 采用放射免疫法检测飞行基础学校毕业学员（１４０名）和飞行学院完成初教机（８２名）、高教机（２９名）训练阶段的学员的血清雌二醇、睾酮、催乳素、卵泡刺激素和黄体生成素５项指标。选择２０名场站地面战士作为对照组。结果 ①各学员组雌二醇、睾酮、催乳素、黄体生成素、卵泡刺激素和雌二醇／睾酮比值较对照组有不同程度改变;②其中尤以雌二醇、睾酮和雌二醇／睾酮比值改变明显;③各学员组自身比较结果显示,随着飞行时间的延长和训练强度的增大,飞行学员性激素水平的变化较大。结论 飞行训练对飞行学员下丘脑－垂体－性腺轴性激素分泌水平有一定影响,飞行因素引起的性激素失衡可能与飞行人员常见病的发生相关。     

Biochemical characteristics of beta-adrenoceptors in rats after an 18-day spaceflight (LMS-STS78).

BACKGROUND: To ascertain whether there was autonomic adaptation with the development of adrenoceptor hypersensitivity under microgravity, the biochemical properties of the beta-adrenoceptors were determined using (125I)iodocyanopindolol (ICYP) binding in rats flown for 18 d onboard the space shuttle. METHODS: This study was performed on heart and kidneys of 3 groups of 12 animals: the flight and 2 ground control (vivarium and AEM) groups. To distinguish the possible role of the corticosteroids, half of each animal group was bilaterally adrenalectomized (ADX rats) with an aldosterone and corticosterone supplementation while the other half was SHAM operated. RESULTS: The Scatchard analysis of the ICYP-binding in both organs revealed no significant alterations in the dissociation constant (Kd) and in the maximal binding capacity (Bmax) between SHAM flight and control groups. The Kd of the beta-adrenoceptors in the cardiac atria of the SHAM flight rats (74 +/- 5 pm) was significantly higher (p < 0.05) than in those of the ADX flight rats (60 +/- 3 pm) while the Bmax was nonsignificantly higher (1925 +/- 370 in SHAM flight rats vs. 1482 +/- 283 fmol x mg(-1) protein in ADX flight rats). No significant change was determined for the Bmax and Kd values in the kidneys of the ADX and SHAM flight rats. CONCLUSIONS: This work performed on animals did not show any obvious effect of microgravity on the beta-adrenergic function in the heart and kidneys. Inflight rodent sacrifice protocols should definitely ensure assessment of the influence of microgravity on the animals.     

民航飞行人员宇宙辐射受照剂量的估算

目的计算被检测飞行人员个人宇宙辐射年均受照有效剂量。方法根据飞行指令数据使用美国联邦航空署开发的软件CARI 6,计算飞行航线的宇宙辐射有效剂量和乌鲁木齐地区地面的宇宙辐射有效剂量率 ,由运行软件输出数据计算个人年均受照有效剂量。结果乌鲁木齐地区地面个人年均受照有效剂量为 0 .42 0mSv ,新疆航空公司全部航线 1 997～ 1 999年平均宇宙辐射有效剂量率为 2 .381 μSv·h- 1 ( 0 .33～ 3.64μSv·h- 1 )。被检测飞行人员年均受照有效剂量为 2 .1 93mSv·a- 1 ( 0 .887～ 4.41 9mSv·a- 1 )。结论估算的 2 34个受检飞行人员的年均受照有效剂量均小于国际放射防护委员会 (ICRP)建议的限值 2 0mSv·a- 1 。     

Effects of prolonged weightlessness on the swimming pattern of fish aboard Skylab 3.

Two fingerling fish and 50 embryonated eggs of (Fundulus heteroclitus) were flown aboard Skylab 3 in a plastic bag aquarium. Videographic picutres were taken with the on-board color-TV camera on flight Days 3 and 22 and video tapes were made for later evaluation on the ground. When observed first after 3 d in orbital weightlessness, both fish swam in tight circles for a considerable fraction of the observed time resembling the "looping behavior" as observed in previous studies with goldfish in parabolic aircraft flight. The frequency of looping diminished slowly after the third day until normal swimming was prevalent. At flight Day 22, both fish swam normally with their backs turned toward the light source. Looping episodes could still be provoked at this time by gentle shaking of the bag aquarium. Of the fish eggs carried aboard, 96% hatched during the mission. The hatch fry displayed normal swimming behavior.     

飞行员血小板的电子显微镜分型正常值及飞行后变化

用电子显微镜方法，将血小板（PC）分为圆、树突、过渡、展平和崩解五个型。对405例飞行员和550例地面工作人员，分别进行分型计数调查。发现36岁以上飞行员中树突型百分比明显高于同年龄地面人员，随着年龄增长，树突型和展平型均呈上升趋势，其余无差别；65岁以上树突型、展平和崩解型明显高于50岁以下者；飞行前后相比，飞行后PC各型均有不同程度改变。     

Pineal physiology in microgravity: relation to rat gonadal function aboard Cosmos 1887.

For the first time pineal glands obtained from 5 male rats flown aboard an orbiting satellite (Soviet Biosatellite #1887) were analyzed for their melatonin, serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIAA), and calcium content. In addition, plasma 5-HT and 5-HIAA were measured. These parameters were compared to indicators of gonadal function: plasma testosterone concentration and spermatogonia development. Plasma melatonin was low at the time of euthanasia (lights on) and was not different among the experimental groups (flight animals, synchronous controls, and vivarium controls). Pineal calcium of flight animals was not different from ground controls. However, pineal 5-HT and 5-HIAA in the flight group were significantly higher than those in ground controls (p less than 0.05). These findings suggest a possible increase in pineal 5-HT turnover in flight animals which may result in increased melatonin secretion. Since melatonin is known to possess antigonadal properties, the alteration of pineal 5-HT turnover and its expected effects on melatonin secretion may, in part, explain the lower plasma testosterone levels (p less than 0.001) and 4-11% fewer spermatogonia cells (p less than 0.02) observed in flight animals.