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11.
Thyroid cancer risk in Belarus after the Chernobyl accident: Comparison with external exposures 总被引:1,自引:0,他引:1
Jacob P Kenigsberg Y Goulko G Buglova E Gering F Golovneva A Kruk J Demidchik EP 《Radiation and environmental biophysics》2000,39(1):25-31
Within the time period 1990–1993, childhood thyroid cancer incidence due to the Chernobyl accident increased dramatically
in Belarus, especially with regard to the birth cohort January 1, 1971, to May 31, 1986. This rise subsequently slowed down,
i.e. during the period 1994–1996. The respective data were analysed and compared with the results of an analysis on the time
dependence of thyroid cancer incidence in a pooled cohort of persons who had been exposed during childhood to external radiation
with high dose rates. Concerning the period of 5–10 years following exposure, the excess absolute cancer risk per unit thyroid
dose in the latter (external) exposure group was found to exceed the one in the Belarus group by a factor of two. This difference,
however, is not statistically significant. The age-adjusted average excess absolute risk per unit thyroid dose for the period
of 5–50 years following external childhood exposure was found to be 8 female and 14 male cases per 104 person-year · Gy, which is a factor about 2.5 times higher than for the non-adjusted risk in the pooled cohort, as reported
by Ron et al. in 1995. Assessments of future excess thyroid cancer cases due to the Chernobyl accident were done on the basis
of the time dependence of thyroid cancer risk following external exposure. The thyroid cancer incidence among the birth cohort
considered in Belarus and for a period starting from the cessation of the available observation data (1 January 1997) and
extending to 50 years after the Chernobyl accident has been estimated to be about 15,000 cases, with an uncertainty range
of 5000–45,000 cases. According to our calculations, 80% of these cases exceed the baseline risk under enhanced thyroid surveillance.
Received: 8 June 1999 / Accepted in revised form: 20 November 1999 相似文献
12.
为了解福岛核泄漏放射性核素对北太平洋公海渔场的后续性污染影响情况,于2013年8—11月在北太平洋公海渔场(40°—44° N、145°—160° E)采集柔鱼样品,利用超低本底HPGe γ 谱仪分析5种放射性核素.结果表明: 134Cs和110mAg未检测出高于本底值的比活度,而210Pb、137Cs和40K均有检出.其中210Pb在柔鱼体的比活度范围为0.99~7.60 Bq·kg-1,137Cs的比活度范围为最低检测限~0.37 Bq·kg-1,40K的比活度范围为46.00~107.00 Bq·kg-1.210Pb核素含量在柔鱼250~300 mm胴长组分布最高;在200~250和>400 mm胴长组中最低.137Cs含量在柔鱼200~250 mm胴长组中最高;在250~300和350~400 mm胴长组较低.40K核素含量在柔鱼250~300 mm胴长组中最高,在150~200 mm胴长组最低,总体分布比较均匀.3种核素在柔鱼的不同组织中含量不同,但均在内脏中含量最高.通过风险评估发现,北太平洋公海渔场所有检测的海洋生物的放射性核素含量值与基准值的熵值均未超过1,说明目前核辐射对该海域渔业资源的影响暂无大风险.研究可为福岛核事故对海洋环境生态影响及公众健康危害评估提供理论依据. 相似文献
13.
Chunmin Dong Lingling Yang Xiaoping Zhang Hua Gu May L. Lam William C. Claycomb Houhui Xia Guangyu Wu 《The Journal of biological chemistry》2010,285(26):20369-20380
The molecular mechanism underlying the post-Golgi transport of G protein-coupled receptors (GPCRs) remains poorly understood. Here we determine the role of Rab8 GTPase, which modulates vesicular protein transport between the trans-Golgi network (TGN) and the plasma membrane, in the cell surface targeting of α2B- and β2-adrenergic receptors (AR). Transient expression of GDP- and GTP-bound Rab8 mutants and short hairpin RNA-mediated knockdown of Rab8 more potently inhibited the cell surface expression of α2B-AR than β2-AR. The GDP-bound Rab8(T22N) mutant attenuated ERK1/2 activation by α2B-AR, but not β2-AR, and arrested α2B-AR in the TGN compartment. Co-immunoprecipitation revealed that both α2B-AR and β2-AR physically interacted with Rab8 and glutathione S-transferase fusion protein pulldown assays demonstrated that Rab8 interacted with the C termini of both receptors. Interestingly, mutation of the highly conserved membrane-proximal C terminus dileucine motif selectively blocked β2-AR interaction with Rab8, whereas mutation of residues Val431-Phe432-Asn433-Gln434, Pro447-Trp448, Gln450-Thr451, and Trp453 in the C terminus impaired α2B-AR interaction with Rab8. Furthermore, transport inhibition by Rab8(T22N) of a chimeric β2-AR carrying the α2B-AR C terminus was similar to α2B-AR. These data provide strong evidence indicating that Rab8 GTPase interacts with distinct motifs in the C termini of α2B-AR and β2-AR and differentially modulates their traffic from the TGN to the cell surface. 相似文献
14.
目的分析我院急诊科对急性冠脉事件包括急性心肌梗死(AMI)和不稳定型心绞痛(UAP)的院前急救情况,就其存在的问题提出对策。方法回顾性分析1989~2010年救治的急性冠脉事件患者166例临床资料,其中AMI患者72例,UAP患者94例。结果急性冠脉事件发生率占急性心脏事件的48.8%,其院前急救率为31.3%(52/166),院前抢救成功率为82.69%(44/52)。结论(1)急性冠脉事件的院前急救率仍低,主要与患者及其家属不了解急性冠脉综合征的发病先兆和表现等相关知识以及呼救意识有关,因此加强相关知识的群众性普及教育迫在眉睫。(2)缩短出诊半径、加强医务人员对急诊处理特别是院前处理急性冠脉事件知识的培训、完善院前急救设备,是提高急性冠脉事件院前抢救成功率的保障。 相似文献
15.
目的 探讨应用改良早期预警(MEWS)评分指导急性脑血管意外院前急救的临床价值.方法 将院前急救中临床诊断为急性脑血管意外的患者分为常规病情评估急救组(对照组)和进行现场MEWS评分指导急救组(实验组),并比较两组患者的病死率及好转出院率.结果 对照组病死率为17.23%,好转出院率为82.77%;实验组病死率为8.76%,好转出院率为91.24%.两组比较,差异有统计学意义(P<0.05).结论 急性脑血管意外患者院前应用MEWS评分进行病情评估和指导急救,能降低患者的病死率及提高好转出院率,具有较好的应用价值,值得在院前脑血管意外急救中推广应用. 相似文献
16.
Pelin Aribal Kocatürk M. Cenk Akbostanci Canan Işikay Aylin Öcal Deniz Tuncel Güzin Özelçi Kavas Nermin Mutluer 《Biological trace element research》2001,80(2):115-124
Ischemia is associated with the pathological changes caused by the accumulation of reactive oxygen metabolites (ROM) in cerebrovascular
accident (CVA). The aim of this study was to determine red cell copper/zinc-superoxide dismutase (Cu/Zn-SOD) and catalase
activities and copper and zinc concentrations both in plasma and in red cells in CVA. Cu/Zn-SOD and catalase activities of
16 patients, with an average age of 64 yr, were measured spectrophotometrically; copper and zinc concentrations were determined
by atomic absorption spectrophotometer. The results showed that Cu/Zn-SOD activity was increased markedly in patients compared
to the young controls and reached a peak on the d 5 of the disease, whereas the catalase activity of the patients on d 3 and
d 5 were in the normal range, but higher on d 10. The enzyme activities of the elderly group were generally increased compared
to the young controls. Copper and zinc concentrations showed corresponding alterations. These findings suggested that the
effects of oxidative stress in CVA might be reflected in red cell and plasma parameters.
Presented at the III International Congress of Pathophysiology, Lahti, Finland, 28 June–3 July, 1998. 相似文献
17.
F. Auriault L. Thollon J. Peres J. Delotte K. Kayvantash C. Brunet M. Behr 《Journal of biomechanics》2014
This study report documents the development of a finite element (FE) model for analyzing trauma in pregnant women involved in road accidents and help the design of a specific safety device. The model is representative of a 50th percentile pregnant woman at 26 weeks of pregnancy in sitting position. To achieve this, the HUMOS 2 model, which has been validated in a wide range of dynamic tests, was scaled to the morphology of a woman in the 50th percentile and coupled with a model of gravid uterus. During scaling, special attention was paid to the pelvic region which is known to differ considerably in morphological terms between men and women. The gravid uterus model includes a placenta, a fetus, uterosacral ligaments and the amniotic fluid by means of fluid structure interaction formulation. The uterus and the female model were coupled using an original method whereby the growth of an uterus was simulated to compress the abdominal organs in a realistic manner. The model was validated based on experimental tests described in the literature. Additional tests based on abdominal loadings with a seatbelt on Post Mortem Human Surrogates (PMHS) coupled to silicone uterus were also performed. 相似文献
18.
A.V. Kuznetsov 《Mathematical biosciences》2010,226(2):147-155
The purpose of this paper is to develop a model for simulation of the formation of organelle traps in fast axonal transport. Such traps may form in the regions of microtubule polar mismatching. Depending on the orientation of microtubules pointing toward the trap region, these traps can accumulate either plus-end or minus-end oriented vesicles. The model predicts that the maximum concentrations of organelles occur at the boundaries of the trap regions; the overall concentration of organelles in the axon with traps is greatly increased compared to that in a healthy axon, which is expected to contribute to mechanical damages of the axon. The organelle traps induce hindrance to organelle transport down the axon; the total organelle flux down the axon with traps is found to be significantly reduced compared to that in a healthy axon. 相似文献
19.
The pale grass blue butterfly, Zizeeria maha (Lepidoptera, Lycaenidae), has successfully been employed as an indicator species to evaluate acute biological changes in polluted human-living environments after the Fukushima nuclear accident. Here, we quantitatively examined the field sampling efficiency of the butterfly and its associated sexual sampling bias under different conditions, which may provide important information for environmental risk assessment. Sampling data were obtained in 2014 and 2015 from 87 localities across Japan. Across the localities, the mean capture rate was 17 individuals per hour per person, and males represented approximately 80% of the collected butterflies. No significant difference was detected in the capture rate under different weather conditions. Among the four habitats, the riverside showed a significantly higher capture rate than the city park. A shorter sampling time tended to yield a higher capture rate. Comparisons among prefectures and districts of collection localities revealed that the Kanto district had significantly higher percentages of collected males than 4 other districts. Fukushima prefecture also had high percentage, although not significant. A generalized linear mixed model indicated that the capture rate was significantly negatively affected by the agricultural village, the city park, the rainy weather, and latitude and positively by longitude. Together, the present study showed high sampling efficiency and versatility of this butterfly as an indicator for environmental risk assessment but simultaneously suggested preferable conditions for a field sampling design. This study also suggested a possibility that the Fukushima nuclear accident or other factors might have affected behavioral or population dynamics of the butterfly. 相似文献
20.