肝尾状叶的外科解剖及其临床应用

在42例成人肝脏标本上，研究了肝尾状叶的形态，动脉、静脉和肝管的分布特征；尾状叶常有3个突起，即尾状突、乳头突和下腔静脉后突，且变异较大；尾状叶有两个恒定的蒂，其结构排列由浅入深分别是门静脉支、肝动脉支和肝管。尾状叶静脉有2～5支，其中以3支居多，主要汇入下腔静脉肝后段的中、下1／3部的左前壁。中结合解剖学研究总结了施行肝尾状叶肿瘤切除术的方法和经验。     

促肝细胞生长素诱导人肝癌细胞（BEL－7402）凋亡

本文从细胞学、ＤＮＡ凝胶电泳、流式细胞术三方面研究促肝细胞生长素（ｐＨＧＦ）在体外对肝癌细胞增殖活性的影响。结果表明：ｐＨＧＦ对肝癌ＢＥＬ－７４０２细胞增殖有抑制作用，并存在剂量和时间相关性。其４８ｈ的半数抑制浓度（ＩＤ５０）为０．３７ｍｇ／ｍｌ±０．０４ｍｇ／ｍｌ。而３７℃灭活的ｐＨＧＦ对ＢＥＬ－７４０２细胞增殖在１５ｈ无抑制作用，在２４和４８ｈ抑制作用很弱（ＩＤ５０＞１．５ｍｇ／ｍｌ）。ＤＮＡ凝胶电泳结果表明，ｐＨＧＦ可诱导ＢＥＬ７４０２细胞产生细胞凋亡（Ａｐｏｐｔｏｓｉｓ）。流式细胞术（ＦＣＭ）结果显示：ｐＨＧＦ抑制ＢＥＬ－７４０２细胞增殖过程是先使细胞停留在Ｇ０／Ｇ１期，继而诱导细胞产生凋亡。后两项结果均显示ｐＨＧＦ对人肝癌细胞凋亡的诱导里时间和剂量相关性。     

髂总动脉分支及其临床意义

在78具成年尸体上详细观察了髂总动脉的分支。髂总动脉外侧支的出现率为30.76%,多起于髂总动脉远侧1/3段(43.33%),始端外径为2.38±0.06(0.90～4.20)mm.起自髂总动脉的髂腰动脉的出现率为10.26%,也多起于髂总动脉远侧1/3段,其始端外径为3.03±0.14(2.50～3.80)mm。记录了此两支动脉的走行和分布,并讨论了它们的临床意义。     

Predictive validity of a national examination for medical graduates in the People's Republic of China

National examinations for medical graduates were introduced on an experimental basis in the People's Republic of China in 1982. To estimate the predictive validity of the National Medical Examination (NME), an investigation of the postgraduate competence of a sample of the participating examinees was conducted in 1984. The sample consisted of 1,717 of the 4,995 graduates from 13 medical colleges who had taken the initial NME. Their scores on the NME and the ratings given them by directors of postgraduate programs in nine aspects of clinical competence were compared by frequency distribution and product-moment correlation coefficients. Scores on the NME were consistent with measures of postgraduate clinical competence and, as a whole, correlated significantly with the ratings of clinical competence, supporting the use of the score on the NME as a predictor of postgraduate clinical competence. However, the extent of the relationship between the NME score and postgraduate clinical competence varied according to the specialty program of postgraduate medical training.     

主要常见病甲襞微循环改变重复性的研究

在目前不能直接观测病人内部器官微循环改变的条件下，应用模糊聚类的理论和方法，对主要常见病有意义的的甲襞微循环改变进行聚类，同时参考国内外相关文献的结果，提出了主要常见病有意义的甲襞微循环改变群。在改变群中任意提出3、4、5、6、7、8项改变指标，形成改变组合，一种组合重复出现二次以上的重复率，随组合改变指标数的增多而减少（70．36％～4．36％）。将改变群分成重要指标和参考指标二类，从每类中提出三项形成组合，重复率仅为0．34％。说明组合方式的影响十分巨大。经过反复探索、大量实践，有可能找出对疾病的符合率较高、漏诊率较低、误诊率较小的最佳组合方式。     

Reduced expression of tissue inhibitor of metalloproteinase (TIMP)-2 in gestational trophoblastic diseases

To elucidate the involvement of type IV collagenases [matrix metalloproteinase (MMP)-2 and MMP-9] and their tissue inhibitors (TIMP-1 and TIMP-2) in the development of gestational trophoblastic disease (GTD), we quantified their levels in hydatidiform mole and choriocarcinoma tissues using specific enzyme-linked immunosorbent assays, and the results were compared with those from normal first trimester placenta. Levels of pro-MMP-2 were increased in hydatidiform mole, and they were further elevated in choriocarcinoma. Levels of pro-MMP-9 in choriocarcinoma and those of TIMP-1 in both hydatidiform mole and choriocarcinoma were also increased. In contrast, TIMP-2 levels were markedly decreased in both hydatidiform mole and choriocarcinoma. Similar results were obtained by the tissue culture of first trimester placenta and hydatidiform mole. Gelatin zymography indicated that the levels of both pro- and activated forms of MMP-2 and MMP-9 were higher in hydatidiform mole and choriocarcinoma. The decreased expression of TIMP-2 in hydatidiform mole and choriocarcinoma was confirmed by Western blot, Northern blot and immunohistochemistry, with the decrease being more pronounced in choriocarcinoma. Taken together, the present study shows that both TIMP-2 mRNA and protein levels are markedly decreased in GTD and the imbalance of MMP-TIMP production, shifted toward greater MMP activity, may be involved in the pathogenesis of GTD.     

Formaldehyde in cryoprotectant propanediol and effect on mouse zygotes

Cryopreservation of human zygotes and embryos has been routinely performed by in-vitro fertilization clinics for many years. Karran and Legge (1996) first reported that formaldehyde (FA) present in the cryoprotective solutions can have a deleterious effect on mouse oocytes. FA is a cytotoxic, carcinogenic and mutagenic chemical. The effect of FA on mouse zygotes was investigated. In addition, the concentrations of FA in propanediol (PROH) obtained from various sources were determined. Pooled 1-cell embryos were dispensed into droplets of modified Ham's F10 or human tubal fluid containing various concentrations of FA. Since bovine serum albumin (BSA) may minimize toxicity additional trials were done as above in the absence of BSA. FA concentration in the standard 1.5 M PROH, from different sources in water, was measured in the same assay using a standard curve of 0-100 microM FA. FA in a complex medium had a significant deleterious effect on embryo development and hatching but only at 1 mM concentration (P < 0.000001; see Tables I-III). There was no significant effect of FA at 100 microM. However, in a simple medium even 50 microM FA decreased embryo hatching. FA was present in 1.5 M PROH from different sources (range 1.0-35.3 microM concentration). It appears that FA concentrations do not increase with storage because FA concentrations were low even after opening and storage for 3 years on the shelf. This suggests that FA is a contaminant during the manufacturing process and may vary from manufacturer to manufacturer and batch to batch. Until further studies are done to confirm the lack of toxicity to embryos during cryopreservation (with or without FA scavengers) it may be prudent to screen all batches of cryoprotectants for FA as part of quality control.      

High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes

As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.