天然水中三卤甲烷前体活性结构的研究

通过实验证实，可用腐植酸（ＨＡ）代表天然水中三卤甲烷（ＴＨＭｓ）的前体。单一模拟化合物（含一个活性空位碳原子的间苯二酚，三个活性空位碳原子的间苯三酚，及甲基酮类化合物的丙酮酸钠）氯化后氯信形成的规律与氯化ＨＡ的不一致。而间苯二酚与丙酮酸钠的混合物（１：４Ｗ／Ｗ）能很好地反映出ＨＡ中活性结构的特性。为今后研究ＴＨＭｓ的形成提供了一个可资定量比较的ＴＨＭｓ前体。     

Asymptomatic autoimmune chronic active hepatitis in a male adolescent

We report a 12-year-old boy presenting with smooth muscle antibody-positive auto-immune chronic active hepatitis. Suspicion of the diagnosis arose after a routine blood test which revealed abnormal liver function tests. In spite of the presence of cirrhosis and patchy necrosis on liver biopsy, our patient never showed any clinical feature of impaired liver function. This observation demonstrates that auto-immune hepatitis may exist for a long time before clinical symptoms appear and probably explains why some cases of auto-immune hepatitis finally present as fulminant liver failure.     

慢性活动性肝炎中单核性细胞超微形态研究

经电镜观察,慢活肝中主要为淋巴细胞及单核巨噬细胞浸润。淋巴细胞分3型,通过4种方式与肝细胞接触,可能代表杀伤肝细胞的动态过程。与肝细胞接触的主要为起细胞毒作用的T_8~+Ⅱ型淋巴细胞及单核巨噬细胞。多数T_4~+淋巴细胞为Ⅰ型淋巴细胞,可能为T辅助细胞。在肝细胞损伤中,淋巴细胞及单核巨噬细胞均起重要作用。     

固尔苏治疗NRDS前后血管内皮分泌功能的改变

目的 :研究肺表面活性物质 (PS)治疗新生儿呼吸窘迫综合征 (NRDS)前后血管内皮分泌功能变化及可能的治疗机理。方法 :用PS制剂固尔苏治疗 18例NRDS患儿 ,于治疗前 3 0min ,治疗后 1、 6、 12、 2 4h ,用硝酸还原酶法测定NO (一氧化氮 )、放射免疫法测定ET (内皮素 )、 6 K PGF1α (6 酮前列环素 )。结果 :固尔苏治疗后患儿NO、 6 K PGF1α明显升高 ,ET明显下降 ,与治疗前比较有显著性差异 (P <0 0 1)。治疗后 1、 6、 12、 2 4hNO、6 k PGF1α、ET各组间两两比较无明显差异 (P >0 0 5 )。结论 :PS治疗NRDS的机理可能是通过改善血管内皮功能发挥作用 ,为用外源性NO吸入和静注前列环素辅助治疗NRDS提供可能的实验依据。     

A review of the effect of pesticide formulations on male fertility

Experimental studies suggest that large numbers of chemicals, environmental and industrial pollutants affect the male reproductive system. At present, almost no information is available on the effects of these adverse agents on human reproduction. Recent reports, however, suggest that in the past 50 years male fertility has declined based on qualitative and quantitative measurements of normal sperm. This study identifies‐among the active ingredients and solvents included in pesticide formulations registered in Italy‐the chemical agents with experimental evidence of male reproductive toxicity. Documents produced by international agencies and organizations such as IARC, EPA, WHO, and original papers from the international literature were systematically reviewed. The results indicate that several pesticide products notified in the Italian Registry contain active ingredients and/or solvents severely affecting testicular function and sperm morphology in laboratory animals. Therefore, exposure to reproductive toxicants occurring among manufacturers and users of pesticide formulations registered in Italy suggest further epidemiologic surveys should be conducted in this area.     

Evaluation of the Crithidia assay to distinguish between auto-immune chronic active hepatitis and systemic lupus erythematosus

The aim of this study was to determine if the Crithidia luciliae assay for auto-antibodies to double-stranded DNA, often positive in systemic lupus erythematosus, is always negative in auto-immune chronic active hepatitis (CAH) as has recently been suggested. Twenty-five patients were identified as having auto-immune CAH. Mean duration of follow-up was 10.5 years. Antinuclear antibodies were detected in 92%, smooth muscle antibodies in 76% and antimitochondrial antibodies in 16%. Antibodies to double-stranded DNA were detected by the Crithidia assay in four patients (16%). Two of these patients had positive tests on only one occasion and no features of systemic lupus erythematosus. In the other two the assay was persistently positive. During follow-up both developed arthritis and serositis but the liver lesion remained the dominant clinical feature. It was concluded that there is significant serological overlap between auto-immune CAH and systemic lupus erythematosus making the Crithidia assay unreliable in distinguishing between them.     

放免法检测乙型慢性活动性肝炎病人红细胞C3b受体的研究

用放免法检测乙型慢性活动性肝炎病人的红细胞ｃ３ｂ受体（ＫＢＣＣＲ１）．结果：病人ＲＢＣＣＲ１明显低于献血员（Ｐ＜０．０５）；抗－ＨＢｓ特异性免疫复合物阳性病人ＲＢＣＣＲ１明显低于阴性病人（Ｐ＜０．０１），与红细胞Ｃ３ｂ受体花环试验检测结果一致。表明乙型慢性活动性肝炎病人ＲＢＣＣＲ１数量减少，活性下降。其原因可能是特异性循环免疫复合物占据了ＲＢＣＣＲ１空位，使ＣＲ１活性下降。     

Active oxygen species generated by monocytes and polymorphonuclear cells in Crohn's disease

Chemiluminescence (CL) analysis of monocytes and polymorphonuclear cells (PMNs) was performed on 13 patients with Crohn's disease (CD) and 10 healthy volunteers. The percentages of monocyte populations in mononuclear cells obtained from the patients with CD were greater than those from the healthy volunteers, but the numbers of PMNs were not different between the two groups. The peak level of phorbol myristate acetate (PMA)-induced CL activity generated by diluted whole blood from the patients with CD was more significantly elevated than that from the healthy volunteers, whereas the peak levels of opsonized zymosan-induced CL activity did not differ between the two groups. In monocytes, the peak levels of both PMA- and opsonized zymosan-induced CL activity were significantly higher in the patients with CD than in the healthy volunteers. CL in PMNs, however, showed no significant difference between CD and controls. It is suggested that monocytes of CD have a large capacity to generate active oxygen species. The present study suggests that excessive active oxygen species released by monocytes and perhaps macrophages may play an important role in formation of the intestinal lesions in CD.This work was supported by the Grant of Tokuteishitsukan from the Japanese Ministry of Welfare and Health.     

Undergraduate and postgraduate dental students''reflection on learning'': a qualitative study

The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described.