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951.
目的 总结143例晚期喉癌患者的临床特征,分析预后的影响因素。方法 回顾性分析2010年1月-2016年12月经中国人民解放军总医院治疗的143例晚期喉癌患者的临床资料。其中,男135例(94.4%),女8例(5.6%);年龄35~79岁,中位年龄58岁。依据患者治疗方案不同分为2组:手术联合术后放化疗组106例和非手术综合治疗组37例。收集患者基本临床情况、治疗、随访及生存情况;生存率及单因素生存分析采用Kaplan-Meier法和log-rank检验,多因素生存分析采用Cox比例风险回归模型。结果 143例晚期喉癌患者的5年总体生存率为67.9%。单因素分析显示,影响晚期喉癌患者预后的临床因素有年龄、临床分期、T分期及肿瘤分化程度等(P值均<0.05);Cox模型多因素分析显示,患者年龄、临床分期、肿瘤分化程度及治疗方式是影响预后的独立危险因素(P值均<0.05)。T4期、临床Ⅳ期患者采用手术联合术后放化疗5年生存率分别为62.2%和59.5%,明显好于非手术综合治疗的18.2%和41.4%,差异均有统计学意义(P值均<0.05)。结论 晚期喉癌患者预后相对较差,影响患者预后的因素包括患者年龄、临床分期、肿瘤分化程度及治疗方式等。对于临床Ⅳ期、尤其是T4期患者,采取手术联合术后放化疗可以获得相对较好的预后。 相似文献
952.
953.
Hsu SC Lin HP Wu JC Ko KL Sheen IJ Yan BS Chou CK Syu WJ 《Journal of virological methods》2000,87(1-2):53-62
Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system. 相似文献
954.
用PCR-SSCP分析检测睾丸女性化综合征患者雄激素受体基因突变 总被引:4,自引:1,他引:4
为进一步探讨睾丸女性化(Tfm)综合征患者发病的分子机理,并为研究雄激素受体(AR)结构与功能关系提供资料,应用银染聚合酶链式反应-单链构象多态性(PCR-SSCP)分析方法对4例Tfm患者的AR基因8个外显子中的7个(B~H)分别进行了研究。结果表明,所有患者AR基因的上述外显子经PCR扩增后均出现与外显子相应长度一致的条带,表明没有明显的缺失或插入突变。2例患者外显子G片段在行SSCP分析时分别有泳动变位,经DNA双链循环测序证实两外显子各有一点突变(Val866Met,T2919→Δ),这些突变均位于AR的雄激素结合区内。其中的缺失突变为国际上尚未报道过的新突变。研究表明,PCR-SSCP分析是检测AR基因突变的快速、简便、可靠的方法。 相似文献
955.
Sun Y Zhou H Zhang Q Wu X 《Artificial cells, blood substitutes, and immobilization biotechnology》2000,28(2):173-180
Lomustine (CCNU) microcapsules was prepared by improved recoacervation method, then mixed microcapsules with 0.7% collagen swelling solution to prepare the emulsion, spreaded the emulsion on the plate to form membrane and cross-linked it, the membrane would be planted into body and was expected to release at steady speed. The concentration of CCNU and the CCNU content of microcapsules were measured by ultraviolet spectrophotometry to observe the release of CCNU be slow and constant, approach to 0-class release approximately. 相似文献
956.
Plasma HIV RNA is a useful surrogate marker for predicting HIV-1 disease progression in infected individuals but provides no information regarding the infectious viral titer. Traditional assays of infectious HIV-1 are, however, time consuming, insensitive, use non-standardized reagents and are subject to selection bias introduced by prolonged cultivation. In this pilot study infectious HIV-1 was detected directly in patient plasma using the indicator line HeLa-CD4-CCR5-LTR/beta-gal in a centrifugation-culture method. Replication competent HIV-1 was identified within 2 days of tissue culture inoculation in six (26%) of 23 plasma specimens. The capability of a new cell line, MT4-CCR5-tat, to amplify plasma HIV-1 was also tested. HIV was cultivated from ten (71%) of 14 specimens using MT4-CCR5-tat cells before titering the virus with the indicator cell assay. Using these stable cell lines in refined versions of this assay it may be feasible to develop rapid, simple methods for titering infectious plasma HIV-1 and for testing the susceptibility of the virus to antiretroviral drugs. 相似文献
957.
Jun Wu Mitchell A. Winnik Rajeev Farwaha Jude Rademacher 《Macromolecular chemistry and physics.》2003,204(16):1933-1940
We describe non‐radiative energy‐transfer experiments to measure the rates of polymer interdiffusion in P(MMA‐co‐BA) latex films formed in the presence of poly(vinyl alcohol) (PVOH). PVOH had relatively little effect on the initial efficiency of energy transfer, even when the amount of PVOH was large enough to form the continuous phase. Since ΦET(0) is a measure of the interfacial area between D‐ and A‐labeled cells in the film, we conclude that under these circumstances the dispersed P(MMA‐co‐BA) copolymer is in the form of clusters with many contacts between particles containing D and A labels. These large amounts of PVOH also reduce the amount of polymer diffusion that takes place when the films are annealed. When smaller amounts of PVOH are present, the effects are measurable but much smaller. In the presence of 2 to 17 wt.‐% PVOH, the polymer diffusion rate is retarded. The magnitude of the effect increases with the amount of PVOH present, and the effect is larger at 45 °C than at 63 °C. We show that the PVOH has its largest influence at the very early stages of polymer diffusion.
958.
壳聚糖纳米颗粒包裹对鼠白细胞介素2基因表达和调节小鼠免疫效应的影响 总被引:4,自引:0,他引:4
本实验制备壳聚糖纳米颗粒 (CNP) ,包裹小鼠白细胞介素 2基因 (mIL 2 )真核表达质粒 (VRMIL 2 ) ,肌注接种 2 1d昆明小鼠 ,观察mIL 2基因体内表达及其对免疫应答和免疫保护的影响。实验结果发现 :CNP包裹VRMIL 2注射小鼠血液中IgG、IgM和IgA不同程度地增多 ,均显著高于CNP包裹空白质粒组 (P <0 .0 5 ) ;其血清中IL 2、IL 4和IL 6的含量明显升高 ,与对照组差异显著 (P <0 .0 5 ) ;外周血液的白细胞和淋巴细胞数量也较对照组显著增加。免疫后 35d以大肠杆菌口服攻毒实验小鼠 ,检测发现 :CNP包裹VRMIL 2组小鼠的上述免疫指标除中性粒细胞外均显著多于对照小鼠 ,VRMIL 2接种小鼠均健康存活 ,而对照小鼠均发病 ;尽管CNP包裹VRMIL 2接种小鼠的体液和细胞免疫指标与未包裹VRMIL 2免疫鼠差异不显著 (P >0 .0 5 ) ,但剂量仅为后者的 1/ 5。这些结果表明 :壳聚糖纳米颗粒包裹VRMIL 2可显著提高外源IL 2基因体内表达水平 ,明显增强体液和细胞免疫水平的效应 ,增强对大肠杆菌的抗病力 ,提示壳聚糖纳米颗粒包裹IL 2基因可明显增强动物的体液和细胞免疫 ,可作为有效的抗感染免疫调节剂。 相似文献
959.
胰腺外科学分段的解剖学基础及其意义 总被引:1,自引:0,他引:1
目的:为胰腺外科学分段提供解剖学基础。方法:在64具灌注标本和4具铸型标本上观察胰内动脉分布、吻合。结果:头由胰十二指肠上动脉和胰十二指肠下动脉供血;颈为一乏血管区;体和尾由胰背动脉、胰支、胰大动脉和胰尾动脉供血。结论:全部胰腺可分为左侧段和右侧段 相似文献
960.
We studied pacemaker current (i
f), the inward current activated by hyperpolarization in rabbit sinoatrial (SA) node myocytes, with the permeabilized-patch-clamp
technique. The tyrosine kinase inhibitors genistein (50 μM) or herbimycin A (35 μM) reduced the amplitude of i
f in response to step hyperpolarizations in the diastolic range of potentials. A two-step voltage-clamp protocol revealed that
the reduction in i
f is due to a decrease in maximal i
f conductance. The observed effects are due to tyrosine kinase inhibition since an inactive analog of genistein did not reduce
i
f. To further examine the mechanism of action, we added 2 mM chlorophenylthio cAMP (CPTcAMP, a membrane-permeant cAMP analog)
to the bathing Tyrode, which increased i
f. Genistein still reduced i
f in the presence of CPTcAMP. This suggests that the pathway mediating the actions of tyrosine kinase inhibition on i
f is independent of cAMP- or protein-kinase-A-mediated phosphorylation.
Received: 28 January 1997 / Received after revision: 21 April 1997 / Accepted: 22 April 1997 相似文献