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1.
IntroductionThe International Atomic Energy Agency (IAEA) organized the 3rd international conference on radiation protection (RP) of patients in December 2017. This paper presents the conclusions on the interventional procedures (IP) session.Material and methodsThe IAEA conference was conducted as a series of plenary sessions followed by various thematic sessions. “Radiation protection of patients and staff in interventional procedures” session keynote speakers presented information on: 1) Risk management of skin injuries, 2) Occupational radiation risks and 3) RP for paediatric patients. Then, a summary of the session-related papers was presented by a rapporteur, followed by an open question-and-answer discussion.ResultsSixty-seven percent (67%) of papers came from Europe. Forty-four percent (44%) were patient studies, 44% were occupational and 12% were combined studies. Occupational studies were mostly on eye lens dosimetry. The rest were on scattered radiation measurements and dose tracking. The majority of patient studies related to patient exposure with only one study on paediatric patients. Automatic patient dose reporting is considered as a first step for dose optimization. Despite efforts, paediatric IP radiation dose data are still scarce. The keynote speakers outlined recent achievements but also challenges in the field. Forecasting technology, task-specific targeted education from educators familiar with the clinical situation, more accurate estimation of lens doses and improved identification of high-risk professional groups are some of the areas they focused on.ConclusionsManufacturers play an important role in making patients safer. Low dose technologies are still expensive and manufacturers should make these affordable in less resourced countries. Automatic patient dose reporting and real-time skin dose map are important for dose optimization. Clinical audit and better QA processes together with more studies on the impact of lens opacities in clinical practice and on paediatric patients are needed.  相似文献   
2.
As compared to cutaneous leishmaniasis, vaccination against visceral leishmaniasis (VL) has received limited attention. In this study, we demonstrate for the first time that an UDP-Galactose: N-acetylglucosamine β 1–4 galactosyltransferase (GenBank Accession No. EF159943) expressing attenuated LD clonal population (A-LD) is able to confer protection against the experimental challenge with the virulent LD AG83 parasite. A-LD was also effective in established leishmania infection. The vaccinated animals showed both cell mediated (in vitro T-cell proliferation, and DTH response) and humoral responses (Th1 type). These results demonstrate the potential of the attenuated clones as an immunotherapeutic and immunoprophylactic agent against visceral leishmaniasis.  相似文献   
3.
We studied the effect of the temporal regulation of herpes simplex virus (HSV) type 1 glycoprotein D (gD-1) expression in Ia+ epidermal cells (EC) and macrophages on virus specific immunity and protection from HSV-2 challenge. gD-1 was expressed on the surface of cells infected with a vaccinia recombinant containing gD-1 under the control of an early vaccinia virus promoter (VP176). It was not expressed in cells infected with a recombinant (VP254) in which gD-1 is controlled by a late vaccinia virus promoter. BALB/c mice immunized with both recombinants seroconverted to HSV-2 as determined by neutralization. However, HSV specific delayed type hypersensitivity (DTH) responses were significantly (p<0.025) higher in VP176 than VP254 immunized animals. Both VP176 and VP254 immunized mice were protected from severe neurological disease due to HSV-2 challenge at 14 days post immunization, but long term protection was observed only in VP176 immunized mice.  相似文献   
4.
Summary The European starling Sturnus vulgaris preferentially incorporates fresh sprigs of particular plant species for use as nesting material. Chemicals found in these plants may act to reduce pathogen and ectoparasite populations normally found in nest environments. The present experiments were performed to test this Nest Protection Hypothesis. In the fild, we experimentally determined that wild carrot Daucus carota, a plant species preferred as nest material, effectively reduced the number of hematophagous mites found within nests relative to control nests without green vegetation. Chicks from nests containing wild carrot had higher levels of blood hemoglobin than chicks from control nests. However, there were no differences in weight or feather development. In the laboratory, we found that wild carrot and fleabane, Erigeron philadelphicus, (also preferred by starlings as nest material) substantially reduced the emergence of feeding instars of mites, while garlic mustard, Alliaria officinalis, (commonly available but not preferred) had little effect on the emergence of mites. We infer that preferred plant material may act to inhibit feeding or otherwise delay reproduction of mites, thereby reducing risk of anemia to developing nestlings.  相似文献   
5.
The design of single-stranded nucleic acid knots   总被引:1,自引:0,他引:1  
A general strategy is described for the synthesis of single-stranded nucleic acid knots. Control of nucleic acid sequence is used to direct the formation of secondary structures that produce the target topology. The key feature of the strategy is the equation of a half-turn of double helical DNA or RNA with a node in a knot. By forming nodes from complementary DNA sequences, it appears possible to direct the assembly of any simple knot. Stabilization of individual nodes may be achieved by constructing them from long regions containing both B-DNA and Z-DNA. Control over the braiding of DNA that acts as a link between node-forming domains can be realized by condensing the nodes into well-defined DNA structures, such as extended domains of linear duplex, branched junctions, antijunctions or mesojunctions. Further topological control may be derived from the pairing of linker regions to complementary single-stranded molecules, thereby preventing them from braiding in an undesirable fashion.  相似文献   
6.
水资源的忧虑   总被引:2,自引:2,他引:0  
水是生态系统中生命必需元素得以无限循环的介质。没有水生态系统,生命就不能维持。在当今世界面临的人口、资源、环境三大问题中,水属于人类赖以生存和社会经济发展的重要物质资源,又和其它两个问题有着密切的关系。因此,水资源的开发、利用和管理已成为世界各国普遍重视的一个重要课题。  相似文献   
7.

1. 1.|When Chinese hamster ovary cells are treated with cycloheximide (10 μg/ml) or puromycin (100 μg/ml) for 2 h before and during heating at 43°C for 3 h, there is protection from hyperthermic killing; i.e. the plating efficiency increases 2000-fold from 3.7 × 10−5 to (6–9) × 10−2.

2. 2.|The total intracellular levels of spermidine and spermine are not altered by the hyperthermic or drug treatments.

3. 3.|The small 30% decrease in intracellular putrescine observed after heating is not altered by drug treatment.

4. 4.|Heat protection by treatment with cycloheximide or puromycin cannot be attributed to changes in levels of total intracellular polyamines.

Author Keywords: Heat protection; cycloheximide; puromycin; putrescine; spermidine; spermine  相似文献   

8.
神经节苷脂对6-OHDA损毁交感神经末梢的对抗作用   总被引:1,自引:0,他引:1  
单次6-OHDA (15mg/kg.i.p.)注射后24h,可使雌性成年小鼠颌下腺内儿茶酚胺荧光神经末梢几乎完全消失;同时用 HPLC 测得腺体内去甲肾上腺素(NA)和多巴胺(DA)的含量下降至正常值的3—4%以下。随着受损交感神经末梢再生过程,NA 和 DA 水平有缓慢的恢复。在损毁2周时 NA 和 DA 含量分别达到正常水平的50%和28%,且在4周时完全恢复。在注射6-OHDA 的同时,和在损伤后12h 内给动物注射4次神经节苷脂(每次50mg/kg.i.p.)并在其后的一周內每天注射一次,可使颌下腺内 NA 含量维持在正常水平;在损毁后4h 及损毁前4d 开始施用神经节苷脂,也可不同程度地对抗交感神经末梢损伤,但作用强度不如前者。实验结果提示:(1)神经节苷脂通过减弱6-OHDA 及其代谢产物的损伤效应能够保护交感神经末梢膜,它可能还有促损伤末梢再生性长芽的作用;(2)损伤后神经节苷脂处理得越早,其效果越好。  相似文献   
9.
Human blood was sheared between rotating polyethylene disks and plasma hemoglobin measured at intervals to produce kinetic hemolysis curves (KHC), plotted as free hemoglobin concentration vs time. The KHC produced by blood samples incubated in the presence of penicillin, streptomycin, gentamicin, and amikacin lie always below those for control samples, indicating a reduction in hemolysis; this reduction was greater as the drug concentration was increased. Explanations in terms of alterations in red cell structure were sought by several characterization tests of amikacin-loaded blood samples. Drug-localization studies demonstrated that significant fractions of the total dosage were associated with the red-cell membrane. Resistive pulse spectroscopy was used to show how amikacin affected cell size, deformability, and osmotic fragility; results were sensitive to storage age of the blood. In all cases, the effect of shearing was to reduce cell size, deformability, and osmotic fragility. Mechanisms for hemolytic protection by drugs are proposed.  相似文献   
10.
It has been suggested that the sociospatial organization of baboon progressions has a protective function in which the most physically powerful troop members, the adult males, play a key role. This theory implies regularities in adult male progression order for different species of savannah baboons with similar social systems. Quantitative progression data are available from two such similar baboon species, olive and yellow, but not from the third, chacma. The order of movement of 15 adult male chacma baboons was determined from 40 progressions observed at the Moremi Wildlife Reserve, Botswana. The chacma males were most often found in the front sixth of progressions, next most often in the second sixth, and about equally often from there to the rear. As expected from the protection theory, this frontal positioning is consistent with available quantitative data from other species of savannah baboons.  相似文献   
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