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1.
《建筑材料放射性核素限量》（GB6566—2001）结束了我国建材标准长期不统一的局面，规定了对建材中放射性实现强制检定的要求，但在装修材料分类、空心材料、废渣利用、测量方法等方面存在着一些不合理的规定。与以往的国家标准相比。对建材中的放射性控制明显放宽，甚至比原来的建材行业标准对石材的控制还要宽，影响了公众的辐射防护安全。对此进行了详细的分析和讨论。 相似文献
2.
Maoru Zhao Chengyan Wang Chao Ji Ruixue Liu Jiani Xie Yuguang Wang Zhanjun Gu 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(27):2206598
A key characteristic of radiation-induced oral mucositis (RIOM) is oxidative stress mediated by the “reactive oxygen species (ROS) storm” generated from water radiolysis, resulting in severe pathological lesions, accompanied by a disturbance of oral microbiota. Therefore, a sprayable in situ hydrogel loaded with “free radical sponge” fullerenols (FOH) is developed as antioxidant agent for RIOM radioprotection. Inspired by marine organisms, 3,4,5-trihydroxyphenylalanine (TOPA) which is enriched in ascidians is grafted to clinically approved temperature-switchable Pluronic F127 to produce gallic acid (containing the TOPA fragment)-modified Pluronic F127 (MGA) hydrogels to resist the fast loss of FOH via biomimetic adhesion during oral movement and saliva erosion. Based on this, progressive RIOM found in mice is alleviated by treatment of FOH-loaded MGA hydrogels whether pre-irradiation prophylactic administration or post-irradiation therapeutic administration, which contributes to maintaining the homeostasis of oral microbiota. Mechanistically, FOH inhibits cell apoptosis by scavenging radiation-induced excess ROS and up-regulates the inherent enzymatic antioxidants, thereby protecting the proliferation and migration of mucosal epithelial cells. In conclusion, this work not only provides proof-of-principle evidence for the oral radioprotection of FOH by blocking the “ROS storm”, but also provides an effective and easy-to-use hydrogel system for mucosal in situ administration. 相似文献
3.
某铀矿山位于海拔3000 m以上,属于高山采矿,由于高山采矿不但存在地质灾害频发、工业场地安全性较差的问题,更重要的是高山铀矿山开采过程中还有具有高山病和放射性危害。在矿山设计中,应充分考虑高原采矿的特殊性,采取有针对性的安全措施,降低矿山开采中风险,使井下生产能够安全、顺利的进行。 相似文献
4.
探究在137Csγ-射线单次辐射下,紫甘薯多糖对小鼠辐射损伤的保护作用及机制。小鼠被分为5组:对照组、辐射模型组、多糖高、中、低剂量组。小鼠在照射前1 d,照后3、14 d检测外周血白细胞总数3次。在照后14 d,处死小鼠,观察多糖对小鼠的胸腺系数和脾脏系数、胸骨骨髓细胞的微核率、脾结节数的影响,测定小鼠血清中的SOD、CAT活性和MDA含量,肝、肾组织中的SOD、GSH-PX、CAT活性和MDA含量各项抗氧化指标。结果实验表明,在4 Gy137Csγ-射线辐射情况下,与辐射模型组进行比较,紫甘薯多糖对小鼠外周血白细胞总数、胸腺系数、脾脏系数、胸骨骨髓细胞的微核率、脾结节数都有显著提高;显著提高小鼠血清中SOD活性,提高脾、肾组织中SOD、GSH-PX和CAT活性,降低小鼠血清、脾、肾组织中MDA含量。结论紫甘薯多糖在体内对137Cs-γ射线辐射损伤小鼠具有保护作用。 相似文献
5.
Jonas Ahlstedt Thuy A. Tran Sven-Erik Strand Magnus Gram Bo ?kerstr?m 《International journal of molecular sciences》2015,16(12):30309-30320
Peptide receptor radionuclide therapy (PRRT) has been in clinical use for 15 years to treat metastatic neuroendocrine tumors. PRRT is limited by reabsorption and retention of the administered radiolabeled somatostatin analogues in the proximal tubule. Consequently, it is essential to develop and employ methods to protect the kidneys during PRRT. Today, infusion of positively charged amino acids is the standard method of kidney protection. Other methods, such as administration of amifostine, are still under evaluation and show promising results. α1-microglobulin (A1M) is a reductase and radical scavenging protein ubiquitously present in plasma and extravascular tissue. Human A1M has antioxidation properties and has been shown to prevent radiation-induced in vitro cell damage and protect non-irradiated surrounding cells. It has recently been shown in mice that exogenously infused A1M and the somatostatin analogue octreotide are co-localized in proximal tubules of the kidney after intravenous infusion. In this review we describe the current situation of kidney protection during PRRT, discuss the necessity and implications of more precise dosimetry and present A1M as a new, potential candidate for renal protection during PRRT and related targeted radionuclide therapies. 相似文献
6.
介绍了^60Co货运列车检查系统的列车辐射安全设计。控制系统通过失效保护、冗余设计、可靠的连锁逻辑、应急措施等,来保证入境待检货车司机、入境客车以及出境列车的辐射安全。 相似文献
7.
《Radioprotection》2009,44(4):505-517
The radiation-induced cataract has been up to now considered as a quite rare pathology, needing high-dose radiations (beyond a dose threshold roughly estimated at 2 Grays to the lens) consisting mainly in head tumour radiotherapy complications. Several new studies on different exposed populations such as astronauts, japanese atomic bomb survivors, people undergoing X-ray examinations, Chernobyl accident “liquidators” as well as data from animal experiments, suggest that dose threshold for detectable opacities as well as for clinical posterior subcapsular cataract occurring, might be far lower than those previously assumed. Even the existence of a dose threshold is no longer an absolute certitude insofar as radiation-induced cataract pathogeny might consist not really in a deterministic effect (direct tissue harmful effect, killing or seriously injuring a critical population of cells) as believed until now, but rather in a stochastic effect (genomic damage in target-cells, altered cell division, abnormal lens fiber cell differentiation). More practically, these new data may lead us to reconsider radioprotection of specifically exposed populations: mainly patients and workers. Regarding workers, labour legislation (lens equivalent dose limit of 150 mSv during 12 consecutive months) might be, in the medium term, reassessed downwards. 相似文献
8.
Durant les dernières années, Radioprotection , le journal de la Société française de radioprotection (SFRP), a évolué vers un journal international à comité de lecture. Cette évolution, simultanément à un changement récent dans le comité éditorial, a conduit à une réflexion sur les objectifs et les domaines d'intérêt du journal. Le point de départ de cette réflexion est une analyse par le comité éditorial des sujets d'intérêts actuels dans les différents champs de la radioprotection et les défis dans les domaines de recherche correspondants comme l'épidémiologie, la radiobiologie fondamentale, la dosimétrie biologique et physique, la radiotoxicologie, l'écotoxicologie et la radioprotection de l'environnement. Cet article présente les résultats de cette réflexion et ouvre la voie pour une évolution des objectifs et des domaines d'intérêt du journal Radioprotection .https://doi.org/10.1051/radiopro/2017007 相似文献
9.
针对大型核设施产生的大流量废气的处理,发展低气阻的整体式催化剂尤为必要。本工作在整体式堇青石载体上生长分子筛涂层,以离子交换法负载活性组分Pt,获得的整体式催化剂具有高的金属分散度,达到了60%。使用该催化剂,在15℃、体积空速为10 000～40 000 h-1、1.0%(体积分数)H2的条件下实现大于99.9%的H2转化率;在25℃、体积空速为50 000 h-1、1.0%H2的条件下实现H2的完全转化。在更低的H2浓度下(0.1%H2和0.5%H2),该催化剂在湿条件下的H2转化率低于干条件下的H2转化率,表明水蒸气会抑制室温催化活性。由于分子筛涂层较Al2O3涂层具有更低的吸水性,整体式Pt/sil-cord催化剂在湿条件下具有比Pt/Al2O3高得多的... 相似文献
10.
硫酸化黑木耳多糖的辐射防护作用研究 总被引：1，自引：0，他引：1
为考察硫酸化黑木耳多糖对~(60)Co-γ射线辐射损伤小鼠的防护作用。以硫酸化黑木耳多糖为受试物,用~(60)Co-γ射线对小鼠进行一次性全身辐射,对小鼠的免疫指标,血清中SOD活力、MDA含量,骨髓DNA含量和骨髓微核率进行测定。结果表明:硫酸化黑木耳多糖对~(60)Co-γ射线辐射损伤小鼠的单核细胞吞噬能力、血清SOD活性有明显的促进作用,并且能够增加小鼠免疫器官指数和骨髓DNA含量,减少血清MDA含量和骨髓微核率,减轻辐射诱导机体的氧化损伤。结论证实,硫酸化黑木耳多糖对~(60)Co-γ射线辐射损伤小鼠具有良好的防护作用。 相似文献