全文从直肠癌的淋巴引流途径与转移规律、淋巴结清扫、对全直肠系膜切除术 ( TME) 的认识、直肠癌术后局部复发形式和术前、术中对淋巴转移的判定五方面进行了综述分析, 认为目前阶段缺少有效、准确、简便的判定淋巴转移的方法, 直肠癌扩大根治术现阶段应有积极的意义。鉴于诸位学者在过去的科研临床工作中, 对直肠癌的临床病理生物学特性有一些可指导手术的经验积累与认识, 为避免盲目扩大, 作者提出选择性保留盆腔植物神经的功能性 直肠癌扩大根治术。

Aim: Observing the Impact of arsenic trioxide (As2O3) on LS-174T cell (colorectal carcinoma cell lines) and the activity of telomerase. Methods: Using the methods of electron microscope (EMS), PCR-Elisa, flow cytometry (FCM) and MTT in vitro (cell culture). Results: (1) With the increasing of concentration of As2O3, the ratio of living cells decreased significantly, IC50=5.23μg/ml; (2) Impact of As2O3 on cell morphology: In experimental group, cells turned round, cell membrane shrunk and nucleus concentrated at karyotheca; (3) Apoptosis curve appeared after 24h, cells turned to apoptosis with time-dependent manner; (4) As2O3 inhibited the activity of telomerase of cell extraction obviously with concentration-dependent and time-dependent manner after 24 h, 48 h and 72 h respectively. Conclusion: From the experiment in vitro, we can see that As2O3 inhibit LS-174T cell growth mainly by inducing apoptosis, partly by the inhibition of telomerase activity.

Objective: Inhibition mechanism of telomerase inhibitor phosphorothioate antisense oligodeoxynucleotides (PS-ODN) on colorectal cancer cells is probed through cells culture and experimental observation of inhibition function of PS-ODN on LS-174T cells of colorectal cancer. Methods: To induce cells to die by adopting anti-sense technology to block telomerase RNA at reverse transcriptase level, and to evaluate the inhibition effect by means of cell clone forming、growth curve、electron microscope、 FCM、PCR-Elisa、etc. Results: The best dosage of PS-ODN was 10 μ mol/Ls. After ten days’ inhibition, the collective forming rate of LS-174T cells in group PS-ODN was obviously lower than that of those in group CPS-ODN and the contrast group ( P<0.01); The cells in group PS-ODN have obvious morphology change; After 72 hours’ inhibition, the cells in group PS-ODN show apoptosis peak, but this doesn’t happen in contrast group; telomerase activity of group PS-ODN was much lower than that of those in group CPS-ODN and the contrast group( P <0.01). Conclusions: Peculiar polynucleotide sequence can inhibit telomerase activity, and induce cells to wither and die. The treatment tactics of malignant tumours induced by telomerase activity is very promising.

Background Peptide nucleic acid (PNA) has many characteristics useful in molecular biology. This paper described an effective way to raise the cell ingestion rate of PNA so as to kill gastric cancer cells. Methods Heteroduplexes of PNAs and oligonucleotides, wrapped by Lipofectamine 2000, were used to infect SGC7901 cells. The inhibitive effect of heteroduplexes was evaluated by analyzing cell clone forming and cell growth rate. Telomerase activity of SGC7901 cells was detected by polymerase chain reaction enzyme-linked immunosorbent assay (PCR-ELISA) and silver staining assay. Results PNAs showed a dose-dependent inhibition of cell proliferation. The percentage of proliferation inhibition was 99.4% after 7 days; the rate of cloning inhibition was 98. 2% after 8 days; whereas for oligonucleotide groups, at the same concentration, the percentages were 50. 1% and 67. 5% respectively. Antisense PNA-DNA-Lipofectamine 2000 group (AP-D-L group) exhibited significantly different percentages from the control groups ( P < 0.05). The test result indicated that telomerase activity of the AP-D-L group was inhibited ( P < 0.05). At the same time, the impact on cell morphology was observed. Conclusions The results showed that PNAs are potent antisense reagents. The telomeraseassociated therapies are very premising for the treatment of malignant tumours.

AIM: To investigate the antiangiogenic effects of endostatin on colonic carcinoma cell line implanted in nude mice and its mechanism. METHODS: Nude mice underwent subcutaneous injection with LS-174t coloni carcinoma cell line to generate carcinoma and were randomly separatedin to twog roups. Micer eceived injection of vehicle or endostatin every day for two weeks. After the tumor was harvested, the tumor volumes were determined, and the expressions of CD34, VEGF and Flk-1 were examined by immunohistochemical method. RESULTS: Tumor volume was significantly inhibited in the endostatin group (84.17%) and tumor weight was significantly inhibited in the endostatin group (0.19710.049) comparedt ot hec ontrolgr oup( 1.19810.105)(F =2 2.56, P=0.001), microvessel density (MVD) was significantly decreased in the treated group (31.85713.515) compared to the contorlg roup(100.14314.290) (F =1 51.62, P <0.001). Furthermore, the expression of Flk-1 was significantly inhibited in the treated group (34.29%) compared to the controlg roup(8.57%)(X1=13.745, P=0.001). However no significant decrease was observed in the expression of vascular endothelial growth factor (VEGF) between these two groups (X1=0.119, P=0.730). CONCLUSION: Endostatin can inhibit tumor growth and angiogenesis by blocking Vegf/Flk-1p athway. This experiment provides the theory basis for developing a new anti-carcinoma drug through studying the properties of anti-angiogenesis inhibitors. Jia YH, Dong XS, Wang XS. Efects of endostatin on expression of vascular endothelial growth factor and its receptors and neovascularization in colonic carcinoma implanted in nude mice. World J Gastroentero/2004; 10 (22): 3361-3364 http://www.wjgnet.com/1007-9327/10/3361. asp

目的 研究ras癌基因产物p21和nm23转移抑制基因与结肠癌临床病理因素及预后的关系。方法免疫组织化学 [sp] 法 (链霉菌抗生物素蛋白-过氧化酶连接法)。结果 (1) p21阳性表达率为50.50%。与病理分期，组织分化、淋巴结转移，肿瘤大小及侵犯深度无相关性。(2) nm 23阳性表达率为75.25%，与病理分期，组织分化、淋巴结转移，肿瘤大小及侵犯深度无显著相关性。(3) p21阴性表达病例三年、五年生存率为72.00%, 62.00%; p2 1阳性表达病例三年、五年生存率为54.00%， 32.00%，其差异具有显著性（P<0.05）.p21阴性nm23阳性表达病例三年、五年生存率为72.37%，50.00%；nm 23阴性表达病例三年、五年生存率为44.00%，28.00%，其差异具有显著性（P < 0.05)。p1阴性nm23阳性表达病例三年、五年生存率为82.05%，69.23%；p21阳性nm23阴性表达病例三年、五年生存率为20.00%，13.33%，其差异具有极显著性（P<0.01)。结论 (1) p21和nm23在结肠癌中表达，与结肠癌发生发展有关。(2) p21阴性表达病例、nm23阳性表达病例预后好，可作为预后判定指标。p1和nm23联合表达判断结肠癌预后意义更大。

目的：检测胃癌组织及癌旁非癌组织中端粒酶活性的表达，探讨端粒酶活性与各临床病理因素之间的关系。方法：采用PCR-ELISA聚合酶链反应-酶联免疫反应)方法，定量检测68例胃癌组织及40例癌旁非癌组织中端粒酶活性表达。分别按计数和计量资料统计。结果：68例胃癌组织中，60例端粒酶活性表达68.24％)，而40例癌旁非癌组织中，6例端粒酶低活性表达(5％)，两组差异极显著（P0．01)。胃癌组织中端粒酶活性表达与淋巴结的转移呈正相关（X2=4.87 u=2.01 P<0.05)；与组织分化呈负相关女(X2=4.34 u=2.17 P<0.05)；与其他临床病理因素统计学无明显相关性。结论：端粒酶的激活与胃癌的发生发展关系密切，端粒酶活性的检测有可能成为临床胃癌诊断的辅助方法，且可能具有一定的指导术式及预后评估的意义。定量检测端粒酶活性可能更有利于揭示其在恶性肿瘤中的角色。

目的 探讨直肠癌保肛手术发生吻合口瘘的预防和治疗。方法 对我院1978年-1999年问收治的直肠癌保肛手术发生18例吻合口瘘的病例进行统计分析。结果 (1)本组直肠癌Dixon术后吻合口癀发生第为6，08％。(2)本组吻合口瘘病人年龄>60岁占50％。男性占66.7％。(3)吻合口瘘可发生于术后两个月内，但中期吻合口瘘发生率高。(4)冲洗组吻合口自然愈合的平均时间为22.4天，结肠暂时性造瘘组的愈合时间平均为14天。(5)吻合口瘿病例全身反应不重，通过局部处理可达痊愈，并没有影响生存率。结论 (1)吻合口瘘发生与全身状况、术前道道准备、手术操作、吻合口血运和张力、吻合质量、盆腔感染及引流不畅等因家有关。(2)吻合口瘿可以通过局部冲洗或结肠暂时性造瘘获得治愈。(3)预防吻合口瘘的发生．需术者肘病人高度负责，认真对待每一个影响吻合口愈合的因素，就能够减少吻合口瘘的发生。