沙棘汁对致癌物N-二甲基亚硝胺(NDMA)在大鼠体内合成及诱癌的阻断与防护作用

在饲料中加入氨基比林和NaNO_2各2g/kg饲与Wistar大鼠38周后诱发出肝、肺及肾脏肿瘤,其中以肝肿瘤的发生率为100％(17/17),大鼠平均寿命195天。而同时给予沙棘汁饮用的大鼠其肿瘤发生较晚,发癌率较低(88％,15/17),平均寿命270天,显著长于对照组和单纯抗坏血酸组(P<0.01),且肝脏癌变范围较小,病变较轻。结果表明,沙棘汁能有效地阻断N-亚硝基化合物在大鼠体内合成及诱癌,其防癌效果优于等量的抗坏血酸。     

糖尿病合并冠心病的概述

从糖尿病合并冠心病的流行病学、病理基础、发病机理及临床、治疗五个方面论述了糖尿病合并冠心病的现代基础研究,并对其中西医结合治疗提出了方法.     

Preliminary study on the nucleic acid hybridization technic in detecting HSV-2 DNA corresponding sequence of cancer tissues of the uterine cervix

In this paper, 34 samples, 25 from 18 cervical carcinoma patients and 9 from 8 non-cervical carcinoma patients, were assayed using (alpha-32P) dCTP HSV-2 DNA probe and nucleic acid hybridization technic. It was shown that the positive rates of HSV-2 DNA corresponding sequence were 50% (2/4), 36% (5/14) and 12% (1/8) in the in situ cancer, invasive cancer and non-cervical cancer tissues. No HSV was isolated from 7 cancer specimens which showed a positive reaction by nucleic acid hybridization.     

Colposcopic assessment in microinvasive carcinoma of the cervix

Forty of the 87 patients with microinvasive carcinoma (MIC) of the uterine cervix who underwent surgery were diagnosed colposcopically and the results were compared with the cytological and histological diagnoses. The cytology showed preinvasive carcinoma in 20 (50.0%) patients and invasive carcinoma in 19 (47.5%) patients. A correct colposcopic diagnosis was made in nine (22.5%) patients as having microinvasive carcinoma, 21 (52.5%) patients preinvasive carcinoma and eight (20%) patients invasive carcinoma, to sum up accuracy rate as 32.1%. The abnormalities most commonly observed in colposcopy were mosaic, punctuation and white epithelium. In microinvasive carcinoma, the triad co-existed in 43% of the patients. Atypical vessels, characteristic of invasion, were found in only one third of the patients. Microinvasion, therefore, may not be evident on colposcopy alone. It is therefore necessary to apply cone biopsy, prior to definite therapy, to make an accurate assessment of the maximum depth and extent of the invasion prior to definitive therapy.     

Gene expression and structure of immunoglobulin epsilon chains

The study of immunoglobulin genes has been an active area of research in recent years. The study of IgE heavy (epsilon) chain gene, in particular, has a significant impact on our understanding of the IgE system. The localization of the epsilon gene in the cluster of mouse heavy chain constant region genes has been determined, and models for gene rearrangements leading to epsilon chain gene expression have been provided. The regulation of IgE antibody production can thus be discussed in the context of these models in combination with knowledge of the cellular basis of IgE production. Comparison of the epsilon chain sequence among human, rat, and mouse has allowed a better understanding of the evolution and structure-function relationship of the epsilon chain. Furthermore, expression of epsilon chain cDNA in Escherichia coli and demonstration of biological activities of expression products have paved the basis for identification of defined peptides representing the structures for recognition by IgE receptors. These studies are discussed in this review.