癌症的化疗原理

/癌症的化疗原理：化疗就是采用化学药物来进行治疗，化疗治疗癌症的原理是利用不同的细胞对于化疗药物敏感性的不同进行的。增殖旺盛的细胞对于化疗的敏感性高于增殖缓慢的细胞，幼稚细胞对化疗的敏感性高于成熟细胞。癌细胞是身体的增殖旺盛细胞，而且含有幼稚细胞很多，而身体的其他细胞则多数是成熟细胞。因此癌细胞是身体内的化疗敏感组织，也就是说化疗药物对在这些细胞的作用最大。药物抑制核苷酸的从头合成途径。这些药物被设计成核苷酸从头合成途径中有关酶的抑制剂，如氧重氮亮氨酸是Gln的类似物，竞争性的抑制剂，干扰嘌啉和嘧啶核苷酸的从头合成;5-F-U是U的类似物，干扰dTMP的合成;和氨甲基喋呤是叶酸（F）的类似物，干扰FH4的合成，进而干扰嘌啉核苷酸的合成。Thechemotherapy:Thechemotherapyisakindoftreatmentsbychemicaldrugs,basedonthesensitivityofdifferentcells.Thesensitivityofthoseactivelyproliferativeandjuvenileishigherthanthoseslowlyandmature.Cancercellsareproliferativeandmanyofthemarejuvenilewhileothercellsinthebodyaremature.Hencecancercellsarechemical-sensitivetissues,influencedbychemicaldrugsatmost.ManydrugsaredesignedtostopordisturbthesynthesisofDNAofcancercells,suchas5-FUandaminopterindisturbingthesynthesisofdTMPandFH4.放疗的长处：

①很多\t"C:\\Users\\Administrator\\Desktop\\_blank"肿瘤患者通过放疗得到治愈，获得长期生存，如早期鼻咽癌、淋巴瘤和\t"C:\\Users\\Administrator\\Desktop\\_blank"皮肤癌等；②有些患者的放疗疗效甚至同手术疗效一样好，如早期\t"C:\\Users\\Administrator\\Desktop\\_blank"宫颈癌、\t"C:\\Users\\Administrator\\Desktop\\_blank"声带癌、\t"C:\\Users\\Administrator\\Desktop\\_blank"皮肤癌、\t"C:\\Users\\Administrator\\Desktop\\_blank"舌癌、\t"C:\\Users\\Administrator\\Desktop\\_blank"食管癌和\t"C:\\Users\\Administrator\\Desktop\\_blank"前列腺癌等，而患者的说话、发音、咀嚼、进食和排便等功能完好，外观也保留完好；\t"C:\\Users\\Administrator\\Desktop\\_blank"早期乳腺癌通过小手术大放疗后，不仅存活时间同根治术，而且乳腺外观保留基本完好，为世界各国女性乳癌患者所接受；③有些\t"C:\\Users\\Administrator\\Desktop\\_blank"肿瘤患者开始不能进行手术治疗或切除难题，但经术前放疗后，多数患者肿瘤缩小，术中肿瘤播散机会减少，切除率进步，术后生存率进步，如头颈部中晚期癌，较晚期的\t"C:\\Users\\Administrator\\Desktop\\_blank"食管癌、乳腺癌和直肠癌等；④也有些患者需术后放疗，既消灭残存病灶、又进步局部控制率和存活率，如肺癌、\t"C:\\Users\\Administrator\\Desktop\\_blank"食管癌、直肠癌、乳腺癌、软组织赘瘤、头颈部癌和脑瘤等；⑤还有些\t"C:\\Users\\Administrator\\Desktop\\_blank"肿瘤病人因为体质差或有合并症不能手术，或不愿手术者，单纯放疗效果也不错；⑥对于那些病期较晚，或癌瘤引起的骨痛、呼吸难题、\t"C:\\Users\\Administrator\\Desktop\\_blank"颅内压增高、\t"C:\\Users\\Administrator\\Desktop\\_blank"上腔静脉压破和癌性出血等，放疗往往能很好地减轻症状，并达到延永生命的目的TheadvantagesofradiotherapyManypatientswithcancerscanlivelongerbythehelpofradiotherapy,suchasthosewiththeearlynasopharyngealcarcinoma,lymphomaandskincancer,etcSomepatientsthroughtheradiotherapycangetthesameimprovementastheoperations,suchastheearlycervicalcancer,vocalcordcancer,skincancer,tonguecancer,esophagealcancerandprostatecancer,etc.Themostimportantisthattheabilitiesofspeaking,pronouncing,chewing,eatingandexcretingareremainedaswellastheappearanceSomepatients,atthebeginning,arenotfitfortheoperationbutviathepreoperativeradiotherapywhichshrinksthetumor,reducethespreadpossibilityandraisetheresection

ratecanhavemorechancetosurvive,suchasthosewiththeadvancedesophagealcancer,andbreastcancer,etcThepostoperativeradiotherapycaneliminatetheremnantsandraisethecontrolandsurvivalrates,suchaspatientswithlungcancer,esophagealcancer,colorectalcancer,breastcancer,softtissueanythingsuperfluousoruseless,headandneckcancerandbraintumor,etc.Theradiotherapyisalsofitforthosewithfragilehealth,complicationsorunwillingnesstoundergothesurgeryTheradiotherapycanrelievesymptomsandpains,especiallyfor

patients

inadvancedstages放疗的缺点：

①放射治疗设备昂贵，治疗用度较高；

②放射治疗工作职员要责备面和纯熟，包括合格的放射治疗医生、放射物理、放射生物和纯熟的放射技术职员；

③放射治疗周期长，一般需1～2个月；

④放射并发症较多，甚至引起部门功能丧失；

⑤有些\t"C:\\Users\\Administrator\\Desktop\\_blank"肿瘤，尤其是晚期肿瘤患者，放射治疗效果并不完好。ThedisadvantagesofradiotherapyTheequipmentisexpensiveandthetherapycostsalotStaffworkingforthetreatmentmustbespecificallytrained,includingradiationtreatment,doctors,radiationphysics,radiationbiologyandhigh-techradiationtechnologystaffAlltoooften,theradiotherapyperiodislong,usually1-2monthsCompl