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。871Please respect copyright.PENANAd6kRoH7m3v871Please respect copyright.PENANAK8mSl0oL8l
871Please respect copyright.PENANAv4BhkTDl2v
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。871Please respect copyright.PENANANlBm0Vknf5
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。871Please respect copyright.PENANAohL0zBQgOo
871Please respect copyright.PENANAlW6eW9D0yP
(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。871Please respect copyright.PENANA6qzxWuGow1871Please respect copyright.PENANACiyAXYsozc
871Please respect copyright.PENANAp52xYFVf8T
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。871Please respect copyright.PENANAGWJxsFH3WM
871Please respect copyright.PENANAr4SgJxXrq5
(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。871Please respect copyright.PENANAQQNWF06eqi871Please respect copyright.PENANAmQ8LTl4VTQ
871Please respect copyright.PENANAC54XQK24qD
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。871Please respect copyright.PENANAWNe6McpS7Y
871Please respect copyright.PENANAVUCydi4HRG
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)。871Please respect copyright.PENANAIlf0T8i10p
871Please respect copyright.PENANAar8ROyXXZp
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。871Please respect copyright.PENANAuBX8bvD6rO
871Please respect copyright.PENANAEJABNyY9W3
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。871Please respect copyright.PENANAJRIomR7FgI
871Please respect copyright.PENANAxEOFX6NZxi
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。871Please respect copyright.PENANAnPXXNvqzSq
871Please respect copyright.PENANAwQLdHs3Ksk
871Please respect copyright.PENANAz79cfdu2x5
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。871Please respect copyright.PENANAqPourc1yoS
871Please respect copyright.PENANAfYVcX11kgs
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/toc871Please respect copyright.PENANAVYzmIwOxgS
871Please respect copyright.PENANApiuCx7hBcC
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。871Please respect copyright.PENANAMtecdZHFHk
871Please respect copyright.PENANARqGewo8DNf
Link:871Please respect copyright.PENANAq5OTnaJZgM
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio871Please respect copyright.PENANAvRcGrH7Ped
871Please respect copyright.PENANAek5kwAN54Y
871Please respect copyright.PENANAdV1mazP4nn
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。871Please respect copyright.PENANA8Tpwea8dEX
871Please respect copyright.PENANAaBTKS91xVB
Ref1:https://academic.oup.com/jnci/article/99/19/1441/2544230871Please respect copyright.PENANAiTRlc8KFRP