小剂量低LET辐射对人淋巴细胞SCE的影响

本文用磷酸盐Giemsa法观察了小剂量X射线照射对人离体外周血淋巴细胞SCE的影响。其结果照射组各剂量点均不明显地高于对照组,证实了SCE对电离辐射不敏感,说明染色体结构畸变和SCE的发生是彼此独立的两个不同事件。     

Prediction of steady-state bioequivalence relationships using single dose data I-linear kinetics

Simulated data using a linear one- and two-compartment body model with different absorption characteristics were used to evaluate the ability of single dose bioavailability data to predict the relationships that exist at steady state. This was done by comparing the confidence intervals obtained from single and multiple dose data sets for the parameters of Tmax, Cmax, and area under the curve from time zero to infinity (AUC0-infinity). As a consequence of Tmax and Cmax decreasing and increasing from single to multiple dosing regimens, the confidence intervals for these parameters reflected these changes. The 90 per cent confidence interval expressed as a percentage of the reference mean increased or decreased for Tmax dependent upon the ratio of Ka test/Ka reference, and decreased for Cmax while the interval for AUC0-infinity exhibited no predictable pattern and appeared to be influenced by the amount of error in the data set. Alteration of either the dosing interval or the fraction absorbed did not affect the pattern of change in the confidence intervals for Tmax and Cmax, but the latter did result in a decrease in the interval for AUC0-infinity. Analysis of the confidence intervals for Tmax, Cmax and AUC0-infinity in bioequivalency studies for quinidine gluconate and procainamide hydrochloride following administration of single and multiple doses to different subjects appeared to be consistent with the patterns observed for the simulated data sets.     

优化CT扫描参数,降低患者辐射剂量

CT检查中如何有效减少辐射剂量,保护患者,同时保证图像质量,作为从事放射的工作人员应该充分认识。本文从CT检查辐射剂量、优化参数及降低CT检查辐射剂量的途径等方面加以综述。     

Tityus perijanensis González-Sponga (Scorpiones, Buthidae): molecular assessment of its geographical distribution and venom lethality of Venezuelan populations.

An extensive field survey allowed us to expand the geographical distribution of the scorpion Tityus perijanensis in the Perijá range, western Zulia State, Venezuela, including areas where adult cases of severe scorpionism have been reported. 16S ribosomal RNA (rRNA) gene sequencing, DL(50) determination, and native PAGE suggest low genetic and venom proteomic divergence across the distribution range. The results also indicate phylogenetic divergence between T. perijanensis and T. discrepans, the species prevalent in northcentral Venezuela. T. perijanensis venom lethality (0.91-0.94 mg/kg) is comparable to that of the Brazilian T. serrulatus and ranks highest among toxic Venezuelan Tityus studied so far. The data indicate that the Perijá range should be included amongst the endemic areas of scorpionism of Venezuela and Colombia.     

酸枣仁提取物急性毒性实验研究

目的 观察酸枣仁醇提取物的急性毒性反应.方法 ①小鼠尾静脉注射不同剂量的酸枣仁醇提取物,连续观察14 d,记录小鼠的急性毒性反应,并计算LD50及LD50 95%可信限;②小鼠灌胃给药,测定一次给予酸枣仁醇提取物的安全剂量.结果 ①静脉注射酸枣仁醇提取物后,部分小鼠出现中毒反应并死亡,测得LD50为27.5 g·kg-1,LD50 95%可信限为25.1～30.1 g·kg-1,死亡动物尸检,其主要脏器未见病理改变.14 d后存活小鼠体重平均增加20.4%,略高于生理盐水组(18.2%).②小鼠灌胃给药(340 g·kg-1,相当于成人一次用量的326倍)后,连续观察14 d,小鼠全部存活,无明显毒性反应,小鼠体重平均增长17.2%.结论 酸枣仁醇提取物毒性很低,临床给药安全可靠.     

低剂量辐射增强小鼠肿瘤基因-放射治疗效应的免疫学机制研究

目的 探讨低剂量辐射全身照射对小鼠Lewis肺癌移植肿瘤基因-放疗方案中的免疫增强作用机制。方法 小鼠右后肢皮下接种Lewis肺癌细胞建立荷瘤模型,基因-放疗组中小鼠肿瘤局部注射由多聚乙烯亚胺包裹的pEgr-IL18-B7.1重组质粒,分别接受由2 Gy 局部照射和0.075 Gy 全身照射组合的不同治疗方案,通过³H-TdR标记方法检测小鼠CTL和NK细胞毒活性,ELISA方法检测TNF-α和IFN-γ分泌活性,观察各治疗组对荷瘤小鼠抗肿瘤免疫的作用。结果 在pEgr-IL18-B7.1基因治疗方案中,单次大剂量辐射局部照射后加多次低剂量全身照射与常规多次大剂量辐射局部照射相比,小鼠CTL和NK细胞毒活性显著增强,TNF-α和IFN-γ分泌活性有不同程度的增高。 结论 低剂量辐射可以通过促进CTL和NK细胞毒效应,上调TNF-α和IFN-γ细胞因子表达,从而增强机体抗肿瘤免疫功能,提高肿瘤基因-放疗的抑瘤效果。     

Ill-health as a household norm: Evidence from other people's health problems

This paper proposes that an individual's self-assessed health (SAH) does not only suffer from systematic reporting bias and adaptation bias but is also biased owing to confounding health norm effects. Using 13 waves of the British Household Panel Survey covering the period 1991–2005, I show that, while there is a negative and statistically significant correlation between SAH and individuals' own health problem index, this negative effect reduces with the average number of health problems per (other) family member. The relative health bias is small, however, which implies that measures of SAH may not suffer seriously from systematic health norm bias. This is an important finding for researchers working with SAH data as it indicates that we do not have to worry too much about controlling for confounding influences from the health of other household members when estimating SAH regression equations.     

美国头颈癌患者生存资料分析

为使国内头颈癌生存分析的基本方法与国际一致，规范生存率分析的基本方法，以利于相互比较．本文以文字及表格方式，简述生存分析基本术语的概念、意义和应用，并介绍2002年第6版《美国头颈部肿瘤TNM分期》的1-5年观察生存率、相对生存率。     

Safety, tolerability and pharmacokinetic study of recombinant human parathyroid hormone in healthy male Chinese subjects

AIM： To determine the safety, tolerability and pharmacokinetic parameters of a new drug recombinant human parathyroid hormone [ rhPTH （1-84）] in healthy male Chinese subjects. METHODS： domly divided Thirty-six healthy male volunteers were rangroups received into 3 groups. The volunteers in these single subcutaneous injection of rhPTH （ 1-84） in a dosage of 1, 2 and 4 μg/kg respectively. Blood samples were obtained before and after administration within 24 hours. The rhPTH concentrations in sennn were determined by enzyme linked immunosorbent assay （ELISA）. The pharmacokinetic parameters determined with use of standard noncompartmental analysis were the maximum serum concentration （ Cmax ）, the time to attain that concentration （ tmax ）, and the area under the serum concentration-time curve up to 24 hours（ AUC0-24 ） and up to infinity （AUC0-∞）. Dose proportionality of pharmacokinetic parameters （AUC, Cmax of every volunteer of each dosage and A UC was computed from log transformed data） and was examined by mean of analysis of variance （ANOVA） using SPSS software package. In the study, subjects＇ symptoms, objective signs, and vital signs, including blood pressure, heart rate, respiratory rate and body temperature, were checked and 12-lead electrocardiography was recorded before and after drug administration within 24 hours. Routine laboratory tests, including hematology, blood biochemistry, serum electrolyte, and urinalysis, were performed before and after drug administration within at 24 hours.[第一段]     

Acute urticaria and hepatitis complicating high-dose methotrexate therapy

We report an unusual case of anaphylaxis and hepatitic dysfunction in a child with the administration of the twenty-third course of high-dose methotrexate. The latter had been used as an adjuvant to prevent pulmonary metastases and the prior 22 courses had been well tolerated. An attempt to reinstate methotrexate after the twenty-third course was again followed by a similar reaction. © 1995 Wiley-Liss, Inc.