教育的氛圍及環境對兒童發展的影響極為強大,能否為下一代提供理想的學習環境,絕對是家長們需要深思的一道問題。833Please respect copyright.PENANAt0qIUTmg9K833Please respect copyright.PENANA51aZgHcUeC
833Please respect copyright.PENANAvbKVA8v2NK
同樣道理,癌細胞的周遭環境亦為它提供了有利抵禦外來藥物侵襲的能力。833Please respect copyright.PENANAHGL8v2Aqg3
要消滅癌細胞的話,必須了解它如何與周遭環境互動,再對其加以入手。833Please respect copyright.PENANAvIKykRoKDg
833Please respect copyright.PENANAB12Yq8mBT1
(圖2)癌細胞的周遭環境極為複雜,事實上學界不少會以「器官」而非「細胞」來冠稱癌症,皆因它與多款周遭細胞建立了不少互利關係並寄予依賴,而非以單一個體的方式生存。833Please respect copyright.PENANAi5xwbIx3Ng833Please respect copyright.PENANAzS5MVgvyOi
833Please respect copyright.PENANASYi2cJraGW
基於癌細胞與周遭環境互動所涉及的範圍非常之多,本篇將只會粗略講及營養及氧氣這一範疇。833Please respect copyright.PENANArESUdZWIRV
833Please respect copyright.PENANAUJ31G2bRZ1
(圖3)血管是運送營養及氧氣的主要途徑,基於癌細胞的血管結構並不完整及參差不齊,以及腫瘤過度生長使靠近核心部份的區域遠離血管,腫瘤的某部份區域是經常性處於低氧氣及缺乏營養的狀態。833Please respect copyright.PENANAhJt5hT0QWe833Please respect copyright.PENANAJXloSAAwWO
833Please respect copyright.PENANASHCDdtRhum
當然,這是實體腫癌才會遇上的情景,血癌或者浮遊在血液循環系統的癌細胞則較少會面對營養或氧氣缺乏的局面。833Please respect copyright.PENANAYKZ2X3dAXt
833Please respect copyright.PENANAr4Rrk3Sjd4
然而,從右圖可見,距離血管超過60μm的區域已經沒有氧氣能夠抵達,而腫瘤半徑超過100μm基本上是等閒之事,所以很多時候均會把腫瘤的環境定性為低氧狀態(Hypoxia),或完全缺氧(Anoxia)。833Please respect copyright.PENANA9oOYoaLFv3
833Please respect copyright.PENANATUmMsr5UWF
外來的藥物需要經由血管輸送抵達癌細胞才能發揮功用,藥物基乎無法抵達癌細胞與血管距離較遠的區域,導致藥物沒能以有效的濃度抵達腫瘤各處。833Please respect copyright.PENANANdNVZJMBlo
833Please respect copyright.PENANAZpKYvtmy7S
而且癌細胞在缺氧缺營養的狀態下,生長速度會有所減慢,這正好避過不少針對快速生長細胞特性的化療藥物追捕。833Please respect copyright.PENANAI7ohtdT7uZ
833Please respect copyright.PENANA3VVEQPEFVx
除藥物外,放射性治療的放射線必需依靠氧氣作為媒體才能傳遞及散播,因此這方法沒能有效根治在低氧環境下的癌細胞區域。833Please respect copyright.PENANA5fVVa2zgmI
833Please respect copyright.PENANAFYRxqywX4t
833Please respect copyright.PENANAKxgo8jZshx
如果想我快啲出文的話,請入去Penana網站科普專欄–薯不揀單俾一個like以及Bookmark,這對我非常之重要。833Please respect copyright.PENANAq4TeWDyBD2
833Please respect copyright.PENANAjf72o9dmys
Link: https://www.penana.com/story/66244/%E7%A7%91%E6%99%AE%E5%B0%88%E6%AC%84-%E8%96%AF%E4%B8%8D%E6%8F%80%E5%96%AE/toc833Please respect copyright.PENANAg3yHkuMNW3
833Please respect copyright.PENANAlqZbmO3r78
同時亦可以在Penana網站裡按「買一嚿/半嚿薯仔」,以課金的方式推動我繼續搜羅資料寫文,多謝。833Please respect copyright.PENANACjx0qqz18h
833Please respect copyright.PENANAhT6GOPKvfM
Link:833Please respect copyright.PENANApsz3Op7MRA
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio833Please respect copyright.PENANAR0Vl2cdndl
833Please respect copyright.PENANAzTww404e9G
833Please respect copyright.PENANAMdHqpnhamY
除非Facebook及IG重開侵侵的account,否則我的IG將不會再作更新,只會寄居本土LIHKG及Penana。833Please respect copyright.PENANA5Gl8G8bb2s
833Please respect copyright.PENANAoCKWPkkD6P
Ref1:https://academic.oup.com/jnci/article/99/19/1441/2544230833Please respect copyright.PENANA6JM00Z7krk