The cross-sectional area of umbilical cord components in normal pregnancy.

OBJECTIVE: To determine the normal cross-sectional areas of the umbilical vein, umbilical artery, and Wharton jelly in healthy pregnancies, and correlate the obtained values with fetal anthropometric parameters. METHODS: A cross-sectional study was performed with 312 women between the 24th and 39th weeks of a normal pregnancy. The cross-sectional areas of umbilical cord vessels were measured at the junction of the cord and fetal abdomen, and the values were subtracted from the total cord cross-sectional area to assess the cross-sectional area of the Wharton jelly. The anthropometric parameters analyzed were biparietal diameter, head circumference, femur length, and estimated fetal weight, and the Spearman correlation was used to assess the correlation between the cross-sectional areas of umbilical cord components and fetal anthropometric parameters. A polynomial regression analysis was performed to identify the curves that best adjusted to mean and standard deviation according to gestational age. RESULTS: A statistically significant correlation was observed between the cross-sectional areas of cord components and fetal anthropometric parameters (P<0.001) as well as gestational age (P<0.001). CONCLUSIONS: Reference measurements of the cross-sectional areas of umbilical cord components are important tools in the assessment of fetal growth.     

儿童癌症幸存者成年后的慢性疾病

由于治疗方法的进步,近80%的儿童和青少年癌症患者能够长期生存。在美国,约有270000例儿童癌症的幸存者,即每640名20至39岁成年人中就有一名幸存者。大量的幸存者有利于儿童癌症治疗后长期健康结果的研究。现在可以明确的是,化疗和放疗所致的儿童各器官系统损害在临床上可能潜伏多年。为了全面了解治疗儿童癌症而继发的健康问题,重要的是衡量三项长期结果:健康状况、死亡率和患病率。这三项中,关于前两项已有相当好的研究报道。在一项对20227例癌症5年生存者的回顾性分析中,Mertens等发现以下原因导致的超额死亡率具有统计学意义:继发癌症(…     

Mutations in Emery-Dreifuss muscular dystrophy and their effects on emerin protein expression

Seventeen families with Emery-Dreifuss muscular dystrophy (EDMD) have been studied both by DNA sequencing and by emerin protein expression. Fourteen had mutations in the X-linked emerin gene, while three showed evidence of autosomal inheritance. Twelve of the 14 emerin mutations caused early termination of translation. An in-frame deletion of six amino acids from the C-terminal transmembrane helix caused almost complete absence of emerin from muscle with no localization to the nuclear membrane, although mRNA levels were normal. This shows that mutant emerin proteins are unstable if they are unable to integrate into a membrane. A 22 bp deletion in the promoter region was expected to result in reduced emerin production, but normal amounts of emerin of normal size were found in leucocytes and lymphoblastoid cell lines. This shows that DNA analysis is necessary to exclude emerin mutations in suspected X-linked EDMD. Emerin levels in female carriers often deviated from the expected 50% and this was due, in at least two families, to skewed emerin mRNA expression from the normal and mutated alleles. In one family with a novel deletion of the last three exons of the emerin gene, a carrier had a cardiomyopathy and very low emerin levels (<5% of normal) due to skewed X-inactivation. In the three autosomal cases of EDMD, emerin was normal on western blots of blood cells, which suggests that autosomal EDMD is not caused by indirect reduction of emerin levels.      

日本血吸虫SjCa8基因的原核表达及其免疫学特征分析

目的表达和纯化日本血吸虫钙结合蛋白(SjCa8),研究其免疫学特征。方法重组质粒pET32a ( )-SjCa8经诱导表达后,获取纯化蛋白SjCa8,利用ELISA、Western-blot和动物保护性实验检测SjCa8的免疫学特征。结果成功获取了纯化蛋白SjCa8,该蛋白能免疫识别血吸虫感染小鼠血清和血吸虫病患者血清。SjCa8免疫Balb/c小鼠可获得较高滴度的特异性抗体,诱导宿主产生35．31%的减虫率和35．68%的减卵率。结论纯化蛋白SjCa8具有良好的免疫原性和免疫反应性,具有作为血吸虫病免疫诊断和疫苗候选分子的研究价值。     

几丁糖与人工骨联合应用预防椎板切除术后硬膜外粘连的实验研究

目的:观察椎板切除术后用几丁糖(CHT)的同时在椎板缺损处植入磷酸三钙人工骨(TCP)预防硬膜外瘢痕粘连的效果。方法:40只纯种日本大耳白兔随机分成A、B、C、D四组,制作L4椎板损伤模型。A组硬膜外涂布生理盐水,B组硬膜外涂布几丁糖,C组硬膜外覆盖人工骨,D组硬膜外涂布几丁糖的同时加人工骨覆盖。术后12周对椎板切除部位进行大体观察、组织学观察及生化检查,比较各组间瘢痕形成和粘连情况。结果:B、C、D组的改良Rydell-Balazs粘连韧度评分、胶原含量及改良Nussvaum组织学评分均优于A组(P<0.01),D组优于B组与C组(P<0.05),B组与C组无显著性差异(P>0.05)。结论:联合应用几丁糖和人工骨能有效预防硬膜外瘢痕粘连的形成,比单独应用几丁糖和人工骨预防效果好。     

变应性鼻炎脱敏治疗的效果观察

目的观察变应性鼻炎（AR）脱敏治疗的效果，探讨影响变应性鼻炎脱敏治疗效果的相关因素。方法对185例AR患者通过皮肤试验，选择敏感变应原浸液，按递增剂量进行常规皮下脱敏治疗。根据患者治疗前后的症状和体征得分情况，分为显效、有效和无效。选择性别、年龄、病程、病情、伴慢性鼻窦炎、伴哮喘、脱敏治疗时间、皮试反应等8个影响变应性鼻炎脱敏治疗效果的可能因素进行多元回归分析，筛查影响脱敏治疗效果的因素。结果总有效率74．6％，其中显效22．9％，有效51．7％。影响脱敏治疗效果的主要因素是治疗时间，即时间越长，效果越好（P〈0．01）；其次是年龄因素，年龄越小，效果越好（P〈0．05）；伴慢性鼻窦炎和伴哮喘也可能影响脱敏治疗效果（P值分别为0．072和0．069）。结论变应性鼻炎脱敏治疗是有效的，脱敏治疗时间越长、年龄越小，效果越好。     

Digital beam attenuator technique for compensated chest radiography

The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.