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1.
目的研究低剂量重离子辐射(LDR)对小鼠造血系统的适应性反应特征。方法对小鼠给予大剂量(2.0 Gy)12C+6射线照射前预先采用0.050,0.075 Gy 12C+6离子束全身照射,其中一批小鼠24 h处死,测定外周血指标、脏器系数、骨髓细胞微核率、骨髓DNA含量;第二批小鼠接受大剂量(2.0 Gy)全身辐照后观察其30 d存活情况。结果与大剂量直接照射组相比,0.050Gy低剂量照射组小鼠外周血白细胞明显升高,骨髓DNA含量升高,小鼠骨髓细胞的微核率降低(均P<0.05~0.01),其余指标无统计学差异。0.075 Gy低剂量照射后小鼠外周血白细胞与照射对照组比较有一定下降,其余指标无明显差异。结论低剂量碳离子束照射能拮抗大剂量照射后引起的骨髓细胞损伤,对造血组织产生适应性反应,对重离子治疗肿瘤及放射防护具有一定参考意义。  相似文献   

2.
目的研究低剂量重离子辐射(LDR)对小鼠造血系统的适应性反应特征。方法对小鼠给予大剂量(2.0 Gy)12C+6射线照射前预先采用0.050,0.075 Gy 12C+6离子束全身照射,其中一批小鼠24 h处死,测定外周血指标、脏器系数、骨髓细胞微核率、骨髓DNA含量;第二批小鼠接受大剂量(2.0 Gy)全身辐照后观察其30 d存活情况。结果与大剂量直接照射组相比,0.050Gy低剂量照射组小鼠外周血白细胞明显升高,骨髓DNA含量升高,小鼠骨髓细胞的微核率降低(均P〈0.05~0.01),其余指标无统计学差异。0.075 Gy低剂量照射后小鼠外周血白细胞与照射对照组比较有一定下降,其余指标无明显差异。结论低剂量碳离子束照射能拮抗大剂量照射后引起的骨髓细胞损伤,对造血组织产生适应性反应,对重离子治疗肿瘤及放射防护具有一定参考意义。  相似文献   

3.
目的 观察低剂量辐射诱导EL-4淋巴瘤细胞周期进程的适应性反应。方法 用X射线照射离体EL-4淋巴瘤细胞,其诱导剂量(D1)为25~200mGy(12.5mGy/min),攻击剂量(D2)为1.5Gy(287mGy/min),D1和D2间隔6h。通过流式细胞仪检测其细胞周期各时相百分数的变化。结果 当D1和D2分别为25~100mGy和1.5Gy,或分别为75mGy和0.5~2.0Gy,D1+D2各组G0/G1期细胞百分数不同程度低于各自D2组,而S期细胞百分数明显高于各自D2组(P<0.05、P<0.01或P<0.001)。结论 上述结果显示,EL-4淋巴瘤细胞在1.0~2.0Gy照射前6h接受25~100mGy照射,可在体外诱导其细胞周期进程的适应性反应。  相似文献   

4.
目的 观察Radaway抗辐射胶囊对小鼠γ射线辐射损伤的保护作用。方法 将120只雄性昆明小鼠随机分为I(外周血白细胞计数)、Ⅱ(骨髓细胞微核检测)、Ⅲ(骨髓DNA含量测定)3大组,每大组又随机分为高、中、低剂量组和辐射对照组。各组根据不同指标选择不同的照射时间均以同一剂量γ射线全身照射1次。结果 以3Gy剂量照射后第14天各剂量组的外周血白细胞计数均显著高于辐射对照组(P < 0.01);照射后第3天,中、低剂量组的骨髓细胞微核率显著低于辐射对照组(P < 0.01),低剂量组的骨髓DNA含量显著高于辐射对照组(P < 0.01)。结论 Radaway抗辐射胶囊对小鼠γ射线辐射损伤具有显著的保护作用。  相似文献   

5.
X射线全身照射对小鼠骨髓细胞周期的影响   总被引:15,自引:0,他引:15  
目的 研究不同剂量X射线全身照射对小鼠骨髓细胞周期的影响。方法 采用PI标记及流式细胞术(FCM)检测细胞周期的变化。结果 发现,1.0-6.0GyX射线线全身照射后12h,小鼠骨髓细胞G1及G2期明显增高,而S期明显减少;同时发现,0.05-0.2Gy低剂量X射线全身照射后72h,G1期骨髓细胞明显减少。而S期细胞明显增高。结论 0.5Gy以上剂量X射线全身照射可诱导小鼠骨髓细胞G1及G2期阻滞,使骨髓细胞增殖明显受抑;而0.2Gy以下低剂量照射则可刺激骨髓细胞增殖。  相似文献   

6.
目的比较不同剂量X射线照射后实验小鼠生物学指标的变化,以建立辐射损伤动物模型。方法用三种辐射剂量率(0.04 Gy/h/d、0.08 Gy/h/d、0.12 Gy/h/d)的X射线对三组昆明小鼠(辐射剂量由低到高分为L、M、H组)进行连续7天全身照射,同时设立不接受辐射的对照组(NC),辐射后检测各组小鼠脏器指数、外周血细胞计数、骨髓有核细胞计数、血清MDA含量和SOD活性等指标的变化,同时比较辐射前后各组小鼠体质量和肝脏、脾脏指数的改变。结果照射后7天,L组小鼠体质量明显低于NC组以及M、H组(P0.05); M、H组小鼠脾脏指数显著低于NC组(P0.01)和L组(P0.05);不同剂量辐射组小鼠外周血WBC和骨髓有核细胞数量均较NC组显著降低(P0.05,P0.01);与NC组比较,M组小鼠血清MDA含量显著升高(P0.05)、SOD活性显著降低(P0.05)。结论慢性累积性低剂量辐射小鼠模型的最佳造模方法为辐射剂量率0.08 Gy/h/d、连续辐射7天,累积辐射剂量0.56 Gy。  相似文献   

7.
目的探讨碳-12(12C)重离子诱导正常人疱疹病毒(EBV)-转化淋巴细胞染色体畸变的生物效应。方法以照射能量为165 Me V/u,剂量率为0.3~0.5 Gy/min,照射剂量分别为0.0、0.1、0.3、0.5、0.7、1.0和2.0 Gy的12C重离子来辐照对数增长期正常人EBV-淋巴细胞,分别培养至照后48、72 h收获细胞(分别设为48和72 h组),收获前2 h加秋水仙素,制片,计算染色体畸变细胞率、"双+环"畸变率以及总非稳定性畸变率,并拟合剂量-效应回归方程。结果 48 h组的"双+环"畸变率在0.3~2.0 Gy约为72 h组的2倍。2组染色体畸变细胞数量均随照射剂量的增加而增加,呈剂量-效应关系(P<0.01)。48 h组的畸变细胞率、"双+环"畸变率以及非稳定性畸变率在0.0~2.0 Gy的剂量-效应回归方程分别为Y=0.024+0.708 D-0.175 D2[校正决定系数(R2c)=0.963,P<0.01]、Y=-0.034+0.531 D-0.128 D2(R2c=0.950,P<0.01)和Y=0.009+0.868 D-0.089 D2(R2c=0.980,P<0.01);72 h组的上述指标分别为Y=0.039+0.388 D-0.084 D2(R2c=0.976,P<0.01)、Y=-0.013+0.247 D-0.062 D2(R2c=0.900,P<0.01)和Y=0.034+0.490 D-0.046 D2(R2c=0.987,P<0.01)。结论12C重离子诱导正常人EBV-转化淋巴细胞畸变随照射剂量增加而增加;染色体畸变在0.0~2.0 Gy存在一定剂量-效应关系,符合二次多项式回归模型。  相似文献   

8.
目的 探讨孕期接受微波辐射对仔鼠遗传学方面的影响.方法 选择健康昆明小鼠45只(雌鼠30只,雄鼠15只),按雌∶雄为2∶1合笼.将妊娠的雌鼠随机分为对照组、低剂量组和高剂量组,分别采用0、570、1 400 μW/cm2的模拟辐射源对孕鼠进行全身辐射,进行其子代骨髓细胞染色体畸变(chromosome aberration,CA)试验、姐妹染色单体交换(sister chromatid exchange,SCE)试验和嗜多染红细胞微核试验.结果 高剂量组SCE的频率(2.64±0.21)高于对照组(1.49±0.23),差异有统计学意义(P<0.05).染色体畸变率和微核率有随剂量升高而上升的趋势.但高剂量组、低剂量组、对照组间染色体畸变率和微核率差异均无统计学意义(P>0.05).结论 孕期微波辐射暴露对仔鼠的遗传物质具有一定的影响.  相似文献   

9.
银杏叶黄酮抗辐射效应研究   总被引:21,自引:0,他引:21  
目的:研究银杏叶中黄酮的抗辐射作用。方法:以碱性水提取法从银杏叶中分离出总黄酮(GBF),调配成低剂量(10 mg/100 ml)、中剂量(20 mg/100 ml)、高剂量(100 mg/100 ml)水溶液,分别给小鼠灌胃,10 d后,以总剂量8.5 Gy 60Co-γ射线整体辐射,再灌胃10 d,观察30 d存活率。另取小鼠,分六组(低、中、高GBF剂量组,辐射对照组,正常对照组,及环磷酰胺组),分别灌胃低、中、高剂量GBF水溶液,另三组灌胃蒸馏水,连续11 d后,低、中、高剂量GBF组及辐射对照组以总剂量1.0 Gy γ射线照射,再灌胃7 d,灌胃停止后D21 测小鼠骨髓微核率及精子畸变率及淋巴细胞测转化率。结果:低、中、高剂量GBF水溶液可分别提高辐射小鼠存活率31.7 %,25.3 %和26.5 %( P<0.05),低剂量GBF使淋巴细胞转化率显著提高(P<0.01),骨髓微核率及精子畸变率有一定程度降低。结论:低剂量银杏叶黄酮具有较强的抗辐射作用,其作用机制与提高小鼠免疫力有关。  相似文献   

10.
低剂量辐射对小鼠蛋白质代谢的影响   总被引:1,自引:0,他引:1  
目的 : 了解一次性低剂量辐射对小鼠蛋白质代谢是否有影响 ,为辐射防护提供参考。方法 : 选用生长期和成年期小鼠各 3 0只 ,随机分成 3组 ,雄雌各半。分别接受 0 ,2 5 0 m Gy,5 0 0 m Gy60 Coγ射线一次全身照射 ,剂量率为 78.6 c Gy/min。每只动物每天定量给予 4g饲料 ,照射后第 7d起恢复自由进食 ,测定动物照射后连续 3 d的氮平衡 ,每 3 d称一次体重。照射后 1 0 d测定血红蛋白 (Hb) ,血清总蛋白 (TP)和血清非蛋白氮 (NPN)。结果 : 成年期小鼠在照射后 6 d时体重显著减少 (P<0 .0 1 ) ,恢复自由进食后体重减轻得到恢复。氮平衡试验中生长期小鼠 5 0 0 m Gy组 ,成年期 2 5 0 m Gy和 5 0 0 m Gy剂量组的正氮平衡低于相应的对照组 (P<0 .0 5 )。照射 5 0 0 m Gy使 Hb和 TP有所下降 ,同时 NPN升高 ,但未达到统计学显著差别。结论 : 一次性暴露于 2 5 0m Gy电离辐射对氮代谢有不良效应。  相似文献   

11.
Determinations of benzene concentration in blood and of phenol in urine were made by head-space gas chromatography techniques on samples taken near the end of the work day from two groups of workers potentially exposed to low levels of benzene in the work-place atmosphere. Preliminary results suggest that benzene in blood is more reliable than phenol tests for assessing both exposure and uptake of benzene. Normal values of phenol in urine (10 mg/liter or less) were found in nearly all those cases in which benzene was detected in the blood.  相似文献   

12.
目的 了解绵阳市2012年市售蔬菜中农药残留情况,为食用蔬菜监管提供依据.方法 全部样品均按照GB/T 5009-2003的方法进行农药的残留检测.依据GB 2763-2005《食品中农药最大残留限量》进行判定.结果 2012年共检测蔬菜165份,农药检出率和超标率分别为72.12%和23.64%.豆类、根茎类、叶菜类、瓜果菜类和食用菌类蔬菜检测农药残留超标率分别为8.00%、23.53%、36.00%、5.26%和27.03%,差异有统计学意义(x2=11.41,P<0.01).不同种类农药超标率差异有统计学意义(x2 =62.42,P<0.01).夏季和冬季蔬菜农药超标率差异无统计学意义(x2=3.44,P>0.05).结论 绵阳市叶菜类蔬菜中农药残留情况较为严重,应采取有效措施,加强蔬菜的监督管理,从源头禁止高毒农药的使用,加大蔬菜种植、销售环节的监测,确保市民食用蔬菜的安全.  相似文献   

13.
恶性肿瘤已成为中国居民的主要死因之一。近些年来,中国政府积极推进肿瘤预防和控制领域的研究工作,取得了很大的进步。本文简要汇总中国在肿瘤流行病学领域的研究进展,具体包括2019年的肿瘤负担、癌症危险因素及其干预、筛查和早期发现、癌症防治专项行动(2019-2022年)方案等方面,以期为我国肿瘤防治工作的有效开展提供技术支撑和理论依据。  相似文献   

14.
15.
芜湖地区儿童隐孢子虫病调查   总被引:3,自引:0,他引:3       下载免费PDF全文
1989年5月~9月,对安徽省芜湖市五所医院儿科就诊的腹泻患儿进行隐孢子虫病调查。粪检腹泻患儿3 498人,卵囊检出率1.9%。男女检出率无差异;6个月内的患儿中未检出卵囊阳性者;86.2%的卵囊阳性者分布于7个月~4岁年龄段;乡村患儿的卵囊检出率2倍于城市患儿;病例呈高度散发状态;卵囊检出率从6月下旬开始上升,在本调查中,92.5%的病例分布于6月下旬~9月。所见病例,从临床表现到大便性状均无特殊,且均呈自限性,病程似较文献报道者为短。  相似文献   

16.
Objective: The objective of this study is to examine if overall correlation exists among cadmium levels (Cd) in the general environment, dietary Cd intake, and Cd body burden of local residents. Methods: Eleven prefectures in Japan were selected as the areas where large-scale data on Cd levels in urine of adult women (40–49 and 50–59 years of age, respectively) were available to calculate geometric mean (GM) values for each of the prefecture. Other data were cited from published or previously established databases on Cd in the sediments of river bottoms (as a representative of Cd in the environment), Cd in rice for local consumption, and Cd in daily food duplicate samples collected from local women populations, and calculated for GM values for the prefectures. The GM values were subjected to correlation matrix and regression analysis. Results: Marginally significant (P<0.10) correlation was detected between Cd in sediment and Cd in rice. Furthermore, correlation of Cd in sediment was significant with Cd in total foods (P<0.05) and possibly with Cd in urine (P<0.05–0.10). Importance of data on Cd in rice paddy soil as a missing link is discussed. Conclusions: Correlation was demonstrated in the flow of Cd transport from the environment (expressed as Cd contents in river sediments) to humans (in terms of Cd in urine) among general populations in Japan.  相似文献   

17.
目的:了解引起神经内科住院患者医院感染的危险因素,采取有效的护理措施,以降低医院感染的发生率和死亡率。方法:结合多年临床经验,对医院感染不同的危险因素进行分析及提出护理对策。结论:神经内科医院感染发病率较高,获得途径以外源为主,针对主要危险因素的发生原因,我们应加强病房管理,严格执行消毒隔离制度,合理应用抗生素,加强基础护理和健康教育,缩短住院天数,以降低神经内科医院感染的发病率。  相似文献   

18.
目的调查住院婴儿疾病分布情况。方法利用SAS8.0对汕头市2003年住院婴儿2923例病例进行统计分析。结果婴儿住院的病因包括:早产、新生儿窒息、呼吸道及消化道感染、新生儿黄疸以及先天性疾病等;造成婴儿死亡的前5位病因主要是出生窒息、窘迫、先天性肺炎、新生儿吸人性肺炎以及先天性心脏畸形;婴儿的住院时间越长,入院情况越危急,受到医院感染的机会越大;入院婴儿平均住院日为7.089天,平均住院费用3717.834元。结论婴儿发病入院主要由于先天性疾病以及后天感染,这是家庭及社会进行婴儿健康干预与促进的重点。  相似文献   

19.
BACKGROUND: Ragpickers are informal workers who collect recyclable materials to earn a small wage. Their life and working conditions are extremely precarious. The ergonomic hazards and musculoskeletal pain in a sample of ragpickers in Pelotas, a city in southern Brazil are examined. METHODS: Two comparison groups were available: a matched sample of non-ragpickers from the same poor neighborhoods, and a random sample of the general population of the city. The cross-sectional study gathered data by interview on 990 individuals in 2004. Musculoskeletal pain was assessed using the Standardized Nordic Questionnaire. RESULTS: Ragpickers reported higher prevalences for most awkward postures and ergonomic exposures compared to neighbors with other demanding manual jobs. The prevalence within the last 12 months of low back pain (LBP), lower extremity pain (LEP), and upper extremity pain (UEP) among ragpickers were 49.2%, 45.1%, and 34.9%, respectively; levels similar to those reported by neighborhood controls. Both ragpickers and non-ragpickers reported considerably higher ergonomic exposures, and more prevalent LBP, than the general population. CONCLUSIONS: Ragpickers experience many occupational hazards and ergonomic stressors. Their overall prevalence of musculoskeletal pain was similar to a comparison group with other physically demanding manual jobs. For LBP, this prevalence was substantially higher (49% vs. 35%) than in the general population.  相似文献   

20.
Changes in social inequalities in health in the Basque Country   总被引:6,自引:4,他引:2       下载免费PDF全文
STUDY OBJECTIVE: To determine the extent of the inequalities in self reported health between socioeconomic groups and its changes over time in the Basque Country (Spain). DESIGN: Cross sectional data on the association between occupation, education and income and three health indicators was obtained from the Basque Health Surveys of 1986 and 1992. Representative population samples were analysed. In 1986 the number of respondents was 24 657 and in 1992, 13 277. SETTING: Basque Country, Spain. MAIN OUTCOME MEASURES: The effect of socioeconomic position on health and the magnitude of social inequalities in health were quantified using the odds ratios based on logistic regression analysis, and the Relative Index of Inequality. RESULTS: As was expected, social inequalities in self reported health existed in both surveys, but the social gradient was greater in 1992. Social differences varied according to gender and health indicator. According to education an increase in social inequalities was observed consistently in all the health indicators except long term conditions in women. A consistent increase in inequalities in limiting longstanding illness was also observed according to all socioeconomic indicators. CONCLUSIONS: These results agree to a large extent with those of previous studies in other countries. In this context the unequal distribution of material circumstances and working conditions between socioeconomic groups seem to play a major part in health inequalities. The worsening of the labour market during this period and the onset of a new economic recession may explain the increase in social inequalities over time.  相似文献   

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