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61.
Phytocystatins are plant cysteine proteinase inhibitors that regulate endogenous and heterologous cysteine proteinases of the papain family. A cDNA encoding the phytocystatin BrCYS1 (Brassica rapa cysteine proteinase inhibitor 1 ) has been isolated from Chinese cabbage (B. rapa subsp.pekinensis) flower buds. In order to explore the role of this inhibitory enzyme, tobacco plants (Nicotiana tabacum L. cv. Samson) containing altered amounts of phytocystatin were generated by over-expressingBrCYS1 cDNA in either the sense or the antisense configuration. The resulting plants hadin vitro enzyme inhibitory activities that were over 10% of those detected in wild type plants. The transgenic plants exhibited retarded seed germination and seedling growth and a reduced seed yield, whereas these properties were enhanced in antisense plants. These data suggest that BrCYS1 participates in the control of seed germination, post-germination and plant growth by regulating cysteine peptidase activity.  相似文献   
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This study presents the results of a Europe-wide training and Quality Control (QC) exercise carried out within the framework of the European Aerobiology Society’s QC Working Group and European COST Action FA1203 entitled “sustainable management of Ambrosia artemisiifolia in Europe (SMARTER)” with the aim of ensuring that pollen counters in Europe are confident in the identification of Ambrosia pollen grains. A total of 69 analysts from 20 countries examined a test slide by light microscopy, which contained Ambrosia pollen and pollen from other Asteraceae that could be recorded in the atmosphere at the same time of year (i.e. Artemisia, Iva, and Xanthium). Daily average pollen concentrations produced by individual participants were compared with the assigned value and the bias was measured by z-score. Both the assigned value and standard deviation for proficiency testing were calculated following the consensus value principle (ISO13528:2005) from the results reported by all the participants in the test. It took a total of 531 days from when the exercise commenced until all 69 analysts reported their results. The most outliers were reported for Artemisia pollen concentrations followed by Xanthium and Iva. The poor results for Artemisia and Xanthium were probably caused by low concentrations on the test slide leading to larger bias due to the unequal distribution of pollen over the microscope slide. Participants performed the best in identifying and quantifying Ambrosia pollen. Performing inter-laboratory ring tests with the same sample is very time consuming and might not be appropriate for large-scale proficiency testing in aerobiology. Pollen with similar morphology should be included in the education process of aerobiologists.  相似文献   
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Abstract

Fusion of 2-trimethylsilylpyridine and tetra-O-acetyl-aldehydo-D-xylose or 2,3:4,5-di-O-isopropylidene-aldehydo-L-arabinose led, after removing of the protecting groups, to 2-(pentitol-1-yl)pyridines of D-gulo and D-ido or L-manno configurations. Dehydration of the sugar-chain with D-gulo and D-ido configurations gave the corresponding 2′,5′-anhydro derivatives, whereas 2-(5-O-isopropyl-L-manno-pentitol-1-yl)-pyridine was the only compound formed by dehydration of the sugar-chain with L-manno configuration. Structural proofs are based on 1H and 13C NMR spectra.  相似文献   
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Two of the most frequently used methods of pollen counting on slides from Hirst type traps are evaluated in this paper: the transverse traverse method and the longitudinal traverse method. The study was carried out during June–July 1996 and 1997 on slides from a trap at Worcester, UK. Three pollen types were selected for this purpose: Poaceae, Urticaceae and Quercus. The statistical results show that the daily concentrations followed similar trends (p < 0.01, R-values between 0.78–0.96) with both methods during the two years, although the counts were slightly higher using the longitudinal traverses method. Significant differences were observed, however, when the distribution of the concentrations during 24 hour sampling periods was considered. For more detailed analysis, the daily counts obtained with both methods were correlated with the total number of pollen grains for the taxon over the whole slide, in two different situations: high and low concentrations of pollen in the atmosphere. In the case of high concentrations, the counts for all three taxa with both methods are significantly correlated with the total pollen count. In the samples with low concentrations, the Poaceae and Urticaceae counts with both methods are significantly correlated with the total counts, but none of Quercus counts are. Consideration of the results indicates that both methods give a reasonable approximation to the count derived from the slide as a whole. More studies need be done to explore the comparability of counting methods in order to work towards a Universal Methodology in Aeropalynology. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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Clinical differential diagnosis of early-onset dementia (EOD) includes familial Alzheimer disease (FAD) and hereditary prion disease. In both disease entities, postmortem brain histopathological examination is essential for unambiguous diagnosis. Mutations in the genes encoding the presenilins (PS1 and PS2) and amyloid precursor protein (APP) are associated with FAD, whereas mutations in the prion protein (PrP) gene are associated with prion disease. To investigate the proportion of EOD attributable to known genes, we prospectively (i.e., antemortem) screened these four genes for mutations by sequencing genomic PCR products from patients with EOD before age 60 years. Family history for dementia was positive (PFH) in 16 patients, negative (NFH) in 17 patients, and unknown (UFH) in 3 patients. In 12 patients, we found five novel mutations (in PS1, F105L; in PS2, T122P and M239I; and in PrP, Q160X and T188K) and five previously reported mutations (in APP, in three patients who were most likely unrelated, V717I; in PS1, A79V and M139V; and in PrP, P102L and T183A) that are all considered to be disease causing. Of these 12 patients, 9 had PFH. This indicates a detection rate of 56% (9/16) in patients with PFH. We found two mutations (APP V717I) in two of the three UFH patients, and only one mutation (PrP T188K) in 1 of the 17 patients with NFH. We conclude that because of the lack of specific antemortem diagnostic markers for FAD and hereditary prion disease, all four genes should be included in a molecular diagnostic program in patients with EOD who had PFH.  相似文献   
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Background and Objective

Both distractions (external and internal) and attention-deficit/hyperactivity disorder (ADHD) are serious risk factors for traffic crashes and injuries. However, it is still unknown if ADHD (a chronic condition) modifies the effect of distractions (irregular hazards) on traffic crashes. The objective of this study was to assess the effects of distractions and ADHD on traffic crash responsibility.

Methods

A responsibility case-control study was conducted in the adult emergency department of Bordeaux University Hospital, France. Subjects were recruited among drivers injured in a motor vehicle crash between April 2010 and August 2011. Responsibility levels were estimated using a standardized method. Frequencies of exposures were compared between drivers responsible and drivers not responsible for the crash. Independent risk factors were identified using a multivariate logistic regression including test interactions between distractions and ADHD.

Results

A total of 777 subjects were included in the analysis. Factors associated with responsibility were distraction induced by an external event (adjusted OR (aOR)  = 1.47; 95% confidence interval (CI) [1.06–2.05]), distraction induced by an internal thought (aOR = 2.38; CI: [1.50–3.77]) and ADHD (aOR = 2.18 CI: [1.22–3.88]). The combined effect of ADHD and external distractions was strongly associated with responsibility for the crash (aOR = 5.79 CI: [2.06–16.32]). Interaction assessment showed that the attributable proportion due to the interaction among participants with both exposures was 68%.

Discussion

Adults with ADHD are a population at higher risk of being responsible for a road traffic crash when exposed to external distractions. This result reinforces the need to diagnose adult ADHD and to include road safety awareness messages delivered by the physician. Developing advanced driver assistance systems devoted to the management of attention lapses is also increasingly relevant for these drivers.  相似文献   
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