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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.
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers.  相似文献   
3.
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   
4.
Aim We evaluate how closely diversity patterns of endemic species of vascular plants, beetles, butterflies, molluscs and spiders are correlated with each other, and to what extent similar environmental requirements or survival in common glacial refugia and comparable dispersal limitations account for their existing congruence. Location Austria. Methods We calculated pairwise correlations among species numbers of the five taxonomic groups in 1405 cells of a 3′ × 5′ raster (c. 35 km2) using the raw data as well as the residuals of regression models that accounted for: (1) environmental variables, (2) environmental variables and the occurrence of potential refugia during the Last Glacial Maximum, or (3) environmental variables, refugia and spatial filters. Results Pairwise cross‐taxonomic group Spearman’s rank correlations in the raw data were significantly positive in most cases, but only moderate (0.3 < ρ < 0.5) to weak (ρ < 0.3) throughout. Correlations were closest between plants and beetles, plants and butterflies, and plants and snails, respectively, whereas the distribution of endemic spiders was largely uncorrelated with those of the other groups. Environmental variables explained only a moderate proportion of the variance in endemic richness patterns, and the response of individual groups to environmental gradients was only partly consistent. The inclusion of refugium locations and the spatial filters increased the goodness of model fit for all five taxonomic groups. Moreover, removing the effects of environmental conditions reduced congruence in endemic richness patterns to a lesser extent than did filtering the influence of refugium locations and spatial autocorrelation, except for spiders, which are probably the least dispersal‐limited of the five groups. Main conclusions The moderate to weak congruence of endemic richness patterns clearly limits the usefulness of a surrogacy approach for designating areas for the protection of regional endemics. On the other hand, our results suggest that dispersal limitations still shape the distributions of many endemic plant, snail, beetle and butterfly species, even at the regional scale; that is, survival in shared refugia and subsequent restricted spread retain a detectable signal in existing correlations. Concentrating conservation efforts on well‐known Pleistocene refugia hence appears to be a reasonable first step towards a strategy for protecting regional endemics of at least the less mobile invertebrate groups.  相似文献   
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6.
The -galactosidase (EC 3.2.1.32) of Corynebacterium murisepticum (inducible by lactose and galactose) was purified by successive column chromatography on Sephadex G-200, DEAE-Sephadex A-50 and DEAE-cellulose (DE52). The enzyme was found to be a dimer of identical subunits of molecular mass 100,000 daltons. The K m values of the enzyme for the substrates lactose and o-nitrophenyl--d-galactopyranoside (ONPG) are 16.7 mM and 4.4 mM, respectively, indicating, its low affinity for the substrates. The Ouchterlony immunodiffusion method exhibited immunological homogeneity of the enzyme preparation. The catalytic site of the enzyme does not take part in antigen-antibody reaction.  相似文献   
7.
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   
8.
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   
9.
Summary The genomic relationship between cultivated sorghum [Sorghum bicolar (L.) Moench, race bicolor, De Wet, 2n=20] and Johnsongrass [S. halepense (L.) Pers., 2n=40] has been a subject of extensive studies. Nevertheless, there is no general consensus concerning the ploidy level and the number of genomes present in the two species. This research tested the validity of four major genomic models that have been proposed previously for the two species by studying chromosome behaviors in the parental species, 30-chromosome hybrids [sorghum, (2n=20) x Johnsongrass, (2n=40)], 40-chromosome hybrids [sorghum, (2n=40) x Johnsongrass, (2n=40)] and 60-chromosome amphiploids. Chromosome pairings of amphiploids are reported for the first time. Chromosomes of cultivated sorghums paired exclusively as 10 bivalents, whereas Johnsongrass had a maximum configuration of 5 ring quadrivalents with occasional hexavalents and octovalents. In contrast, 40-chromosome cultivated sorghum had up to 9 ring quadrivalents and 1 hexavalent. Pairing in the 30-chromosome hybrids showed a maximum of 10 trivalents, and that in the 40-chromosome hybrids exhibited 8 quadrivalents, 5 of which were rings, together with a few hexavalents. Amphiploid plants showed up to 3 ring hexavalents, 1 chain hexavalent and a chain of 12 chromosomes. The data suggest that cultivated sorghum is a tetraploid species with the genomic formula AAB1B1, and Johnsongrass is a segmental auto-allo-octoploid, AAAA B1B1B2B2. The model is further substantiated by chromosome pairing in amphiploid plants whose proposed genomic formula is AAAAAA B1B1B1B1 B2B2.Contribution no. 87-391-J from the Kansas Agriculatural Experiment Station  相似文献   
10.
大叶杨组组间杂交花粉-柱头相互作用的超微结构研究   总被引:3,自引:1,他引:2  
以大叶杨为母本,分别与小叶杨、欧洲黑杨、响叶杨进行人工杂交,并以大叶杨×大叶杨为对照,观察其花粉与柱头相互作用的超微结构变化。结果表明,大叶杨柱头细胞在授粉前表现生理活跃,含丰富的细胞器,壁外被含分支通道的角质层。接受大叶杨及欧洲黑杨花粉的柱头细胞内部仍有丰富的细胞器,膜结构保存完好。接受小叶杨及响叶杨花粉的柱头细胞衰亡较快,授粉部位沉积厚的胼胝质,细胞内部液泡化,膜结构逐渐消失,细胞质电子密度加大。欧洲黑杨花粉行为与大叶杨花粉行为相似,花粉能迅速萌发,并以短管形式穿入柱头,异常行为罕见。小叶杨及响叶杨花粉萌发后只有半数花粉管能以短管形式进入柱头,其中部分管内沉积胼胝质,另半数花粉管在柱头上表现各种异常行为——扭曲、爬行、肿胀、提前破裂释放内容物及先端沉积胼胝质。由各种花粉在大叶杨柱头上的行为和大叶杨柱头对各种授粉的反应判断,与大叶杨杂交亲和力在柱头阶段表现由强至弱依次是欧洲黑杨、小叶杨、响叶杨。  相似文献   
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