慢性阻塞性肺疾病患者呼出气NO含量的变化及吸入NO对其肺功能的影响

为探讨一氧化氮 (NO)在慢性阻塞性肺疾病 (COPD)发病中的作用及吸入NO对COPD肺功能的影响 ,本研究检测了COPD患者鼻、口呼出气中NO的含量及吸入不同浓度 (10～ 80ppm)NO时肺功能和血气指标。结果表明 :COPD患者鼻、口呼出气NO含量均明显低于对照组 (P <0 .0 1) ,且COPD和对照组口呼出气NO含量低于鼻呼出气 (P <0 .0 1) ;吸入 2 0～ 80ppmNO能明显改善COPD患者部分肺通气功能指标(FEV1、FEV1/FVC、FEV1%、PEF) ,且呈效量依赖关系 ,但对肺容量和肺弥散功能指标无明显影响 ;吸入NO后COPD患者PaCO2 增加 ,但对PaCO2 和高铁血红蛋白无明显影响。提示NO合成减少可能介导了COPD的发病 ,吸入一定浓度的NO可改善COPD患者肺通气功能和PaO2     

非常规分割放射治疗的放射生物学基础与临床应用

如何进一步提高肿瘤的放疗疗效是放射临床医师及放射生物学家长期以来密切关注的问题。在放射生物学对放疗的时间、剂量、分割次数深入研究基础上，20世纪70年代开始提出了多种非常规分割的放疗方法，如超分割放疗（HRT）、加速超分割放疗（HART），包括连续加速超分割放疗（CHART、CHART—WEL）、同时小野加量加速超分割放疗（CBHART）、分段加速超分割放疗（SCHART）、后程加速超分割放疗（LCHART）、逐步增量加速超分割放疗（EHART）等和连续加速常规分割放疗（CAIR），并在临床应用中取得了明显的治疗效果。     

Radiotargeting agents for cancer therapy

Although the general radiobiological principles underlying external beam therapy and radionuclide therapy are the same, there are significant differences in the radiobiological effects observed in mammalian cells. In external beam therapy and brachytherapy, emissions are composed of photons, whereas in radionuclide therapy, the radiations of interest are particulate. This article will explore the special features that characterise the biological effects consequent to the traversal of charged particles through mammalian cells. In addition, it will highlight what has been learned when these radionuclides and targeting radiopharmaceuticals are used to treat cancers.     

p（35）Be快中子辐射场生物剂量参数的测定

报道了ｐ（３５）Ｂｅ快中子、γ混合辐射场生物剂量参数，说明了采用双电离室方法测量ｐ（３５）Ｂｅ快中子时，剂量计算中有关因子和参数的确定原则和估算结果；给出了辐射场的中子／γ比，照射野内组织比释动能率分布，以及由比释动能率计算小鼠全身与局部照射和血液样品照射时的吸收剂量转换系数等剂量常参数；最后还对剂量测量的误差问题做了分析。     

Annual number of intraoral radiographs in Denmark and other countries

It has been demonstrated previously that in 1982, 2.4 million intraoral radiographs were taken in Denmark, or 0.47 radiograph per inhabitant. In the present study this frequency is compared to frequencies in other countries. The number of radiographs per inhabitant varied between 1.6 (Sweden) and 0.08 (Hungary). It is concluded that the frequency in Denmark is lower than in Sweden, USA, Norway, and Japan, but higher than in Great Britain, Finland, and Hungary. The increase in use of intraoral radiography was compared for five countries. The frequency curves exhibited nearly identical slopes, but the rates of increase for Great Britain and Denmark were approximately 15 yr delayed in comparison with Sweden, USA, and Japan.     

放射外科组织病理改变(附4例报告)

目的:探讨放射外科治疗的放射生物学效应。方法:报告4例放射外科治疗的手术病理改变,与影像改变及治疗计划等对照研究,结合文献复习,探讨放射生物机理。结果:4例出现不同程度变性、坏死、组织吸收及水肿反应,有剂量及时间依赖性。结论:放射外科治疗后病灶早期改变是血脑屏障紊乱和靶细胞超微结构改变,逐步出现水肿期、坏死期、吸收期及瘢痕期。在坏死期及吸收早期,从治疗体积中心向外依次为坏死区、变性与反应区、水肿区,分别与计算机体层摄影(CT)或磁共振成像(MRI)的中央无强化区、强化环、周围低密度或长T_1长T_2水肿样信号区相对应,水肿样改变主要与灶周剂量较高有关。坏死是靶细胞辐射损伤与血管闭塞相结合的结果,后者为管壁增厚和血栓形成所致。糖皮质激素对灶周水肿的疗效与血管壁损伤程度有关。     

3.7PBq放射生物学研究用60Co辐照装置

本⁶⁰Co辐照装置(源强3.7PBq=10⁵ci)具有平衡式传动机构,比较可靠的安全联锁系统和防护措施,用微型电子计算机设计照射方案和控制运行.装置已用于放射医学、剂量学和辐射加工等领域.     

Potential for therapeutic gain similar to pions by daily combinations of neutrons and low-LET radiations.

Biological studies with negative pi mesons (pions) at the Los Alamos Meson Physics Facility (LAMPF) have shown a relatively constant reduction of shoulder of the survival curve for single cell cultures and relatively constant reduction in the no response region for multicellular tumor spheroids (MTS) with little change in sensitivity (or slope), in both single dose and fractionated experiments. In clinical studies, a trend toward therapeutic gain for pions has been demonstrated in patients treated at LAMPF, with marked, rapid turmor regression for relatively mild acute normal tissue injury and no untoward effects observed over 7 to 24 months. Since the pion beams used therapeutically at LAMPF are characterized by a small amount of high-linear-energy-transfer (LET) radiation (in the range 10 to 20%), it is hypothesized that pion radiation as compared to x-rays increased the differential tolerance to sublethal injury in favor of normal tissues, resulting in therapeutic gain. It is further proposed that the near simultaneous application of high-LET radiation (such as neutrons) and low-LET radiation (such as x-rays) might create a bilogical situation similar to that of pion treatment, potentially resulting in therapeutic gain, although without the added benefit of dose localization obtainable with pions.     

电离辐射诱导microRNA研究进展

微小RNA（microRNA,miRNA）是一类长度为21~23 nt的单链非编码小RNA。在真核生物中miRNA主要通过与编码蛋白质基因的信使RNA（mRNA）配对结合,在转录后水平抑制基因表达。越来越多的证据表明,miRNA与氧化应激特别是辐射生物效应相关,miRNA有可能成为放射病治疗的潜在新靶点。本文概述电离辐射诱导miRNA的研究进展。     

DNA Repair: Translation to the Clinic

It has been well established that an accumulation of mutations in DNA, whether caused by external sources (e.g. ultraviolet light, radioactivity) or internal sources (e.g. metabolic by-products, such as reactive oxygen species), has the potential to cause a cell to undergo carcinogenesis and increase the risk for the development of cancer. Therefore, it is critically important for a cell to have the capacity to properly respond to and repair DNA damage as it occurs. The DNA damage response (DDR) describes a collection of DNA repair pathways that aid in the protection of genomic integrity by detecting myriad types of DNA damage and initiating the correct DNA repair pathway. In many instances, a deficiency in the DDR, whether inherited or spontaneously assumed, can increase the risk of carcinogenesis and ultimately tumorigenesis through the accumulation of mutations that fail to be properly repaired. Interestingly, although disruption of the DDR can lead to the initial genomic instability that can ultimately cause carcinogenesis, the DDR has also proven to be an invaluable target for anticancer drugs and therapies. Making matters more complicated, the DDR is also involved in the resistance to first-line cancer therapy. In this review, we will consider therapies already in use in the clinic and ongoing research into other avenues of treatment that target DNA repair pathways in cancer.