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1.
目的:构建人IL-1Ra和人IL-10真核表达质粒载体并检测其表达。方法:用双酶切方法切取PCDI-IL-1Ra和PCDI-IL-10质粒中包含人IL-1Ra和人IL-10 CDS全长序列的cD-NA片段,并分别连接到真核表达质粒pcDNA3.1上,然后用壳聚糖转染上述质粒到原代软骨细胞,RT-PCR检测其mRNA水平的表达。结果:成功将人IL-1Ra和IL-10 CDS全长序列的cDNA片段克隆到真核表达载体,mRNA水平检测到目的基因的表达明显提高。结论:真核表达质粒可以用于外源基因的原代软骨细胞导入和表达,为进一步的基因治疗研究提供依据。  相似文献   
2.
Rn-222 is the most important source of natural radiation and is responsible for approximately half of the received dose from all sources. Most of this dose is from inhalation of the Rn-222 progeny, especially in closed atmospheres. A Lucas cell technique, using a portable device, “PRASSI” (SILENA mod. 5S), for Rn-222 measurements inside the Centre for Radiation Protection and Radioecology (ZSR), Hannover University was used. The portable radon monitor PRASSI is suitable for radon gas continuous or grab sampling measurements with the scintillation cell technique. In recognition of the wide periodic variations in concentration, measurements were made daily for extended periods. At the same time, meteorological variables, such as temperature and humidity were observed so that their influence on radon levels could be evaluated. The radon average concentration during the year was about 55.9 Bq/m3 which gives rise to an annual effective dose 2.2 mSv y−1. The radon concentration is within the limits prescribed by the International Commission for Radiation Protection. A detailed analysis of radon distribution with seasonal variation is presented.  相似文献   
3.
本文分析了101例成人骨灰样品和5例成人尸解样品中镭-226和钙的含量。实验范围内,人骨中镭-226含量与年龄及骨中钙含量呈二元线性相关关系。用苏州市人口相应的年龄构成计权的人骨中镭-226含量为(5.99+0.08)×10-4Bq/g灰。所测各部位骨的骨灰中镭-226含量的差异无显著性意义;不同部位骨的灰化率差异甚大,由尸解样品中镭-226含量估算的人体软组织中镭-226负荷量约占全身负荷量的20%。此外,本文还根据所测骨、肺、肝,胃,小肠、大肠、骨胳肌和皮肤中镭-226含量,对相应受辐射危险的组织进行了剂量估算,并估算了接受镭-226及其短寿命子体所致年剂量后随机性健康效应发生的几率,将随机性建康效应发生的几率与世界癌症发病率最低的国家或地区的相应组织或器官的癌症发病率相比较,发现前者比后者至少低约二个数量级。  相似文献   
4.
目的了解典型办公场所内氡浓度水平随时间变化规律,为开展办公室内氡浓度水平调查或评价提供有效方案。方法选取典型办公室1间,用脉冲电离室测氡仪AlphaGUARD~开展9个月的连续测量,通过对测量数据的统计,分析办公室内氡浓度水平的变化规律。结果在9个月内,办公室内氡浓度的最大日均值、周均值、月均值以及季度均值与相应的最小值比分别为6.27、2.63、1.41和1.09;周末与工作日平均氡浓度的比值为1.17,工作日中上、下班时间段的平均氡浓度比值为0.86。结论办公场所内氡浓度水平虽然随时间变化,但3个月的连续测量均值基本可反映办公室内氡浓度的年度均值。  相似文献   
5.
The effect of different degrees of avitaminosis B6 in mice on the cytolytic activity of T lymphocytes, measured as the quantity of Na2Cr51O4 released from lysed target cells, was studied on a model of the primary immune response in a mixed lymphocyte culture in vitro. Keeping animals for 3 weeks on a diet without pyridoxine did not affect the ability of the lymphocytes to proliferate in vitro or their cytolytic activity. In animals receiving a diet without pyridoxine for 45 days the content of pyridoxal-5-phosphate in the spleen was 55% lower than in the control. Lymphocytes taken from these animals, when cultured in vitro, showed sharply weakened ability to incorporate [3H]thymidine into DNA in response to the alloantigen. The cytolytic activity of these lymphocytes also was reduced. The ability of different forms of pyridoxine to restore the functions of T lymphocytes, when disturbed by avitaminosis B6, was studied.Laboratory of Systemic Blood Diseases, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 185–188, August, 1977.  相似文献   
6.
A reduction mammoplasty must produce a reduction in volume, a natural lasting shape, and minimal residual scarring. Many attempts to achieve this goal have been developed in recent years. The author described, in 1970, a vertical technique achieving an important reduction and a good shape but with the appearance of the end of the vertical scar below the brassiere line. In 1977, the author [3] modified the technique by the adjunction of a small horizontal scar to eliminate the inconvenience of the visible part of the vertical scar. In this article the author describes his technique which appears to be suitable for most types of breast deformities.  相似文献   
7.
Serum and intracytoplasmic cytokines are mandatory in host defense against microbes, but also play a pivotal role in the pathogenesis of autoimmune diseases by initiating and perpetuating various cellular and humoral autoimmune processes.  相似文献   
8.
Abstract

Purpose: To assess the impact of environmentally relevant levels of ingested 226Ra on a common freshwater fish species.

Methods: Fathead minnow (Pimephales promelas, Rafinesque) were obtained at the first feeding stage and established on a commercial fish food diet containing 226Ra in the activity range 10 mBq/g?1, –10,000 mBq/g?1. They remained on this diet for 24 months and were sampled invasively at 1,6,18 and 24 months to assess growth, biochemical indices and accumulated dose and non-invasively also at 12 and 15 months to assess growth.

Results: Fish fed 10 and 100 mBq/g?1 diet showed a small transitory deregulation of growth at 6 and 12 months. Fish fed higher activities showed less significant or insignificant effects. There was a trend at 18 months which was stronger at 24 months for the population distribution to change in all of the 226Ra fed groups so that smaller fish were smaller and bigger fish were bigger than the controls. There were also significant differences in the ratios of protein:DNA at 24 months which were seen as a trend but were not significant at earlier time points.

Conclusions: Fish fed a radium diet for 2 years show a small and transitory growth dysregulation at 6 and 12 months. The effects predominate at the lower activities suggesting hormetic or homeostatic adjustments. There was no effect on growth of exposure to the high activities 226Ra. This suggests that radium does not have a serious impact on the ecology of the system and the level of radium that would be transferred to humans is very low. The results may be important in the assessment of long-term environmental impacts of 226Ra exposure.  相似文献   
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