胆道并发症发生率的高低往往代表了一个肝移植中心的整体技术水平。欧美成熟的肝移植中心胆道并发症发生率为7%~10%，1年生存率达到90%。来自中国肝移植登记注册网（CTLR）的资料： 香港玛丽医院2006年统计了香港公民在大陆进行肝移植的148例患者，在长期随访中发现，有48%的受体发生了胆道并发症，1年生存率只有59%； 说明目前肝移植胆道并发症的防治仍然是亟待解决的难题。究其原因，还是对胆管微循环保护的研究不够深入和并发症发生的防治体系不够完善，笔者就此谈几点体会。1胆管微循环保护的理论人体肝脏胆管及血管铸型模型的研究显示，胆管为动脉单一供血，肝固有动脉和胃十二指肠动脉终末支分出3点、9点动脉滋养肝外胆管，并构成肝门部胆管周围血管丛(peribiliary vascular plexus,PVP)，胆管的动脉系统与门静脉之间无明显的交通血管，门静脉在胆管的血液供应中作用有限 (图1)。在动脉损伤时胆管很难从别的途径获得充分的血液供应，从而造成胆管的缺血性损伤。碳素墨汁灌注透明法显示，肝门部每个肝叶胆管及其分叉部均有肝固有动脉的较大分支支配，肝动脉的分支与胆管壁微血管之间呈垂直的连接方式。胆管厚切片透明后可清楚地显示出PVP的平面结构: 外层微血管直径较粗，内层微血管象链条一样排列，中层微血管连接在内、外层之间[３](图2)。动脉血流从外层较粗大血管流入位于胆管黏膜下的内层微血管，它是胆管动脉的终末分支,由内层微血管滋养的胆管上皮细胞层是胆管最易受损的部位(Achilles heel)。所以，肝移植中胆管动脉灌洗非常重要，应尽可能选用能够进入胆管黏膜内层血管网的低黏滞度灌注液。笔者研究证实了HCA液结合UW液灌注快速获取无心跳供体（NHBD）的肝脏，其保存效果优于单用UW液、Celsior液或HTK液，采用价廉低黏滞度HCA液联合UW液灌注，既能防止胆管PVP微血栓形成，又能充分发挥UW液对肝细胞和胆管细胞的保护作用.............................
Objective To refine the loss of heterozygosity (LOH) on chromosome 7q21－22 and identify the new tumor suppressor gene(s) in colorectal tumorigenesis. Methods Fifteen polymorphic microsatellite markers were analyzed on chromosome 7 and another 5 markers were applied on chromosome 7q21-22 region in 83 cases of colorectal cancer and normal DNA by PCR. PCR products were electrophoresed on an ABI Prism 377 DNA sequencer. GeneScan 3.1 and Genotyper 2.1 software were used for LOH scanning and analysis. Results A distinct region of frequent allelic deletion was observed on chromosome, another 5 polymorphic microsatellite markers were applied to 7q21-22 and the minimal region of frequent LOH was established on 7q21-22 spanning the D7S657, D7S646 locus. Conclusion Through detailed deletion mapping studies, a critical and precise region spanning the D7S657, D7S646 locus is identified, which must contain one or more unknown tumor suppressor gene(s) on colorectal cancer.