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41.
42.
The primary aims of this study were to establish a client injury baseline for the New Zealand adventure tourism and adventure sport sector, and to examine patterns and trends in claims for injury during participation in adventure activities. Content analysis of narrative text data for compensated injuries occurring in a place for recreation and sport over a 12-month period produced over 15,000 cases involving adventure tourism and adventure sport. As found in previous studies in New Zealand, highest claim counts were observed for activities that are often undertaken independently, rather than commercially. Horse riding, tramping, surfing and mountain biking were found to have highest claim counts, while hang gliding/paragliding/parasailing and jet boating injuries had highest claim costs, suggesting greatest injury severity. Highest claim incidence was observed for horse riding, with female claimants over-represented for this activity. Younger male claimants comprised the largest proportion of adventure injuries, and falls were the most common injury mechanism.  相似文献   
43.
以耐SO2品种巨峰和不耐SO2品种红地球葡萄为材料,研究了葡萄贮藏中SO2伤害与活性氧代谢的关系,结果表明,SO2伤害葡萄体内活性氧水平,GSH含理和ASP活性增加,SOD和CAT活性降低,与红地球相比,巨峰具有较高的SOD活性和GSH水平,受SO2伤害后,巨峰的ASP活性上升幅度大于红地球,其SOD活性和CAT活性的下降幅度低于红地球。  相似文献   
44.
通过观察大气污染物引起大鼠肺损伤的病理组织学变化,分析肺组织内血红素氧合酶1(HO-1)的表达量的变化,为大气污染所致肺损伤的生物学标记物的研究提供科学依据。实验方法如下:将30只Wistar大鼠,随机分为3个实验组(3d、7d、30d组)和3个对照组(3d、7d、30d组),对实验组大鼠染尘染毒后提取所有大鼠肺组织,观察其病理组织学变化;RT-PCR技术检测各组肺组织中HO-1的mRNA表达;Western-blot技术检测各组肺组织中HO-1蛋白的表达。结果显示:实验组(7d及30d)的肺组织病理形态学评分显著高于对照组(7d及30d),实验组(7d及30d)大鼠肺组织HO-1mRNA表达与对照组相比,具有显著性差异(P均〈0.05)。随着吸入大气混合污染物的时间延长,肺组织内的HO-1蛋白表达水平逐渐增高,实验组(7d及30d)与对照组(7d及30d)相比,差异有显著性意义(P〈0.05)。在吸入大气混合污染物后早期(7d),HO-1转录水平升高。持续吸入混合大气污染物(30d),大鼠肺组织出现明显的病理组织学变化,HO-1转录水平、蛋白表达水平均比对照组明显升高。得出结论:可将HO-1作为大气混合污染物所致的肺损伤的早期生物学标记物;采取某些手段增加肺组织HO-1的表达,可能会减少混合大气污染物对肺组织造成的损伤。  相似文献   
45.
《Ergonomics》2012,55(5):891-897
Abstract

To study the usefulness of a screening questionnaire for neck/upper extremity complaints, 165 women in either repetitive industrial, or mobile and varied work, were studied by the questionnaire and by a detailed clinical physical examination. A total of 94 subjects recorded complaintsin the questionnaire. In 140 subjects findingswere recorded at the examination. Most subjects with findings at the clinical examination of shoulders reported complaints in the questionnaire (sensitivity 80%). For the other anatomical regions, the sensitivity was rather low (42– 65%). For all regions, most subjects without findings reported no complaints (specificity 77–97%). A total of 75 subjects were given clinical diagnoses according to a set of predetermined diagnostic criteria. The capacity of the questionnaire to identify diagnoses of shoulders was higher (sensitivity 92%) than for the other regions (66–79%). Of subjects who did not qualify for diagnosis, a majority (specificity 71–81%) did not report complaints in the questionnaire. We conclude that the questionnaire approach gives a fairly good picture of the neck/upper extremity status of a working female population. However, a clear view of the size of a problem is obtained only by a detailed clinical examination, particularly as regards the neck, elbows and hands, for which the questionnaire gave an underestimate.  相似文献   
46.
Protein Rad23, a nucleotide excision repair factor, mainly involves in repairing the DNA damage from environment, such as UV light. The function of Rad23 protein involved in DNA damage repair from many environmental factors has been studied extensively, but it is not clear from ultraviolet irradiation. To further investigate the photo-protective function of Rad23 protein on HeLa cells damaged from UV light irradiation, firstly, HeLa cells were irradiated by UV light and incubated with the fusion protein of pCold-Rad23, then the cell viability and apoptosis rate were detected by MTT and Hoechst33342/Pl fluorescent staining, respectively. The results show that the recombinant Rad23 protein can protect the HeLa cells from UV irradiation, and inhibit the apoptosis of HeLa cell by UV irradiation.  相似文献   
47.
Cryopreservation is the most reliable method for long-term storage of plant genetic resources. A review of cell injury by ice crystals and dehydration during a freeze–thaw cycle is given. For successful regeneration of plants and cultures after cryopreservation of their cells, the development of reliable cryopreservation procedure is required including preliminary cultivation, treatment by cryoprotectors, freezing by different methods, thawing and recultivation. Up to now 27 cell lines successfully resumed their growth after storage in liquid nitrogen and preserved their specific features and biosynthetic potential. Besides, shoot tips of 40 cultivars of potato, rose, strawberry and raspberry regenerated plants both in vitro and in vivo after cryopreservation. The longest storage duration was 25 years. Now in liquid nitrogen we continuously store 24 cell strains of rare medicinal plants, shoot tips of seven cultivars of strawberry and raspberry and seeds of 250 endangered plant species collected over all Russian territory.  相似文献   
48.
Objective To investigate the change of protein expression of lung tissue of rabbit after ischemic preconditioning (IP) and try to elucidate the potential protective mechanism of IP. Methods 12 domestic rabbits were randomly divided into group IP and group control (6 rabbits in each group). All the left lungs were afflicted by ische mia-reperfusion injury except that those in group IP were subject to IP prior to ischemic phase. 2-DE was employed to separate the total protein of the lung tissue. PDQuest analysis software was used to distinguish the differently expressed protein spot. MALDI-TOF-MS and Mascot database searching were exploited to identify these proteins. Results 1) IP attenuated the ischemia-reperfusion lung injury. 2) The proteomic analysis showed 35 target proteins, of which 17 were characterized such as phosphatidylinositol 3-kinase(PI3k) delta catalytic subunit. Conclusions 1) Proteomic is a promising tool to investigate the IP and ischemia-reperfusion lung injury. 2) That IP inhibits inflammatory cascades through phosphatidylinositol 3-kinase signal transduction pathway may be one of its protective mechanism. Foundation item: Project(2004036433) supported by the Postdoctoral Science Foundation of China; project(B2004024) supported by the Science Foundation of Public Health Bureau of Hunan Province  相似文献   
49.
急性放射损伤小鼠血清蛋白质组分析   总被引:5,自引:0,他引:5  
为寻找急性放射病早期诊断指标和新的治疗靶点,探讨辐射损伤的发病机理,采用蛋白质组学的双向电泳和蛋白质氨基酸序列分析技术研究了8Gy γ射线照射后24h小鼠血清蛋白质的变化,鉴定有差异的蛋白质,并用蛋白质印迹(Western blotting)方法进行验证。结果显示,双向电泳发现8Gy照射后24h小鼠血清有一显著变化蛋白点,分子量约为15ku,经氨基酸序列分析发现为结合珠蛋白(Haptoglobin,Hp)的α亚单位。Western blotting方法进一步验证了双向电泳的结果。结果表明,经8Gy γ射线照射后24h小鼠血清中结合珠蛋白发生显著增加,可能在辐射损伤中发挥着一定的作用,此结果为探索急性放射损伤的发病机理提供了新的线索。  相似文献   
50.
The number of immigrants in the United States is at an all time high, yet psychologists have largely ignored the domain of immigrant health. This article considers 1 aspect of immigrant health, risk for pediatric injury. A sample of over 5,000 5-year-old children from impoverished families was studied; approximately 13% had immigrant mothers. Children of immigrants had a significantly lower rate of injury in the prior year. This was particularly true of non-White children of immigrants. Three possible mediators for this finding--assistance with parenting, parenting style, and health care accessibility--were considered, but none explained the difference. The need for further research on the topic and implications of results for injury prevention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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