Ukuqonda le nkinga
Ucwaningo lwesitembu se-stem luyinkinga eyinkimbinkimbi futhi ephikisanayo. Ngaphambi kokuba ube yikho noma ngokumelene nayo, kufanele uqonde ngokugcwele amagama, amandla, nemiphumela yokucwaninga kwe-stem cell. Kunemininingwane ecacile eyenza ukuhlolisiswa kocwaningo lwe-stem cell. Yenziwe:
- inkinga yezombangazwe
- inkinga yenkolo
- ikhwalithi yokukhishwa kwempilo
Maphakathi no-May 2005 uMengameli uBush wathi, "Ngingumsekeli oqinile wecwaningo lwe-stem cell, kodwa ngiye kwacaca kakhulu kuCongress ukuthi ukusetshenziswa komholo womkhokhi wentela ukukhuthaza isayensi ebhubhisa impilo ukuze kusindiswe impilo, mina ngimelene nalokhu. "
Ziyini amaseli we-stem (SC)?
I-SC ihluke kwezinye izinhlobo zamaseli emzimbeni. Kungakhathaliseki umthombo wabo, bayakwazi ukwahlukanisa nokuzivuselela isikhathi eside. Nakuba zingakaziwa, zingakwazi ukuhlinzekela izinhlobo ezikhethekile zamangqamuzana (isib. Isisindo, igazi elibomvu, ubuchopho).
Yiziphi amangqamuzana e-embryonic stem (ESC)?
I-ESC itholakala emibungu ekhuphuka emaqanda ahlanganisiwe e-vitro, emtholampilo we-in vitro fertilization. Banikezwa ngezinhloso zocwaningo ngemvume enolwazi yabanikeli. Ayitholakali kumaqanda azaliswe emzimbeni wesifazane - ukungaqondi kahle okuvamile.
Ziyini ama-cell stem amakhulu (ASC)?
I-ASC ayinayo imingcele, etholakala phakathi kwezinhlobo zamaseli ezahlukaniswa ngezicubu noma isitho. I-ASC ingazivuselela yona, futhi ingahlukanisa ukuze ihlinzekele izinhlobo ezinhlobonhlobo zezinsiza ezikhethekile zezicubu noma isitho. Indima yabo eyinhloko emzimbeni ophilayo ukugcina nokulungisa izicubu ezitholakala kuzo.
I-ESC ne-ASC ifana kanjani nokuthi ihluke kanjani?
Zihlukile kwinombolo kanye nohlobo lwamaseli ahlukanisiwe angaba khona. I-ESC ingaba yizo zonke izinhlobo ezitholakala emzimbeni. I-ASC kuthiwa ingaphansi kakhulu, ngokuvamile ikwazi ukuhlukaniswa phakathi kwezinhlobo ezahlukene zeseli zezicubu zazo zokuvela. Kodwa-ke, obunye ubufakazi bubonisa ukuthi i-ASC evela kumzimba owodwa omdala ingakwazi ukukhiqiza izinhlobo ezahlukene zamangqamuzana omunye izicubu ezindala.
Izinzuzo
Ucwaningo oluqhubekayo ngamaseli e-embryonic stem angakwazi ukubona ukuthi amangqamuzana angama-stem angafani kanjani ahlukaniswe. Kuyaziwa ukuthi ukuguqula noma ukuvala izakhi zofuzo kuyingxenye yenqubo. Ezinye zezimo zezokwelapha ezimbi kakhulu zibangelwa ukuhlukaniswa kweseli okungavamile nokuhlukaniswa.
Ukuqonda kangcono ukuthi lezi zinqubo zilawulwa kanjani ezingeni lezakhi zofuzo zingaholela ku:
- ulwazi olubalulekile mayelana nesibangela sezifo eziningi
- amathuba amasha nokwelapha kangcono
- ukuphulukiswa okungenzeka okungenzeka ngezimo eziningi zezokwelapha
Kulula nje, labo abeseka ukucwaninga kwe-embryonic stem cell cell bakholelwa ukuthi kungabangela ukuphulukiswa okunokwenzeka kwezifo eziningi, kubandakanya:
- I-rheumatoid Arthritis
- Lupus
- Scleroderma
- Isifo sikashukela
- Isifo sikaParkinson
- Isifo se-Alzheimer's
- Isifo senhliziyo
- I-Cancer
- Ukulimala kwentambo yomgogodla
Amaseli e-stem angasetshenziswa futhi ukuhlola izidakamizwa ezintsha. Ngokusho kwe-NIH (National Institutes of Health, "ukuhlola izidakamizwa ngokuphumelelayo, izimo kufanele zifanane lapho ziqhathaniswa nezidakamizwa ezihlukene. Ngakho-ke, ososayensi kuzodingeka bakwazi ukulawula ngokuqondile ukuhlukaniswa kwamaseli okugcoba kuhlobo oluthile lwamaseli lapho izidakamizwa zizohlolwa.Ulwazi lwamanje lwezibonakaliso zokuhlukanisa ukuhlukanisa luba lula kakhulu ukukwazi ukulinganisa lezi zimo ngokufanele njalo zibe namaseli ahlukene ahlukeneyo emithi ngayinye ehlolwayo. "
Isidingo sezicubu nezitho eziguqulwayo zidlula kakhulu ukutholakala okukhona. Ama-stem cells, aqondiswe ukuze ahlukaniswe phakathi kwezinhlobo ezithile zeli cell, anganikeza ithuba lokuvuselelwa kwamangqamuzana namashubhu avuselelekayo ukuphatha izifo eziningi.
I-Cons
Esinye sezimpikiswano eziyinhloko ucwaningo lwe-embryonic stem cell luhlobene nenkolelo yokuthi ukusebenzisa ama-embryus okuphazamisa ukuphila. Abantu abame beqinile ngemuva kwalolu mbono bakholelwa ukuthi ngisho nangenhloso yocwaningo lwezokwelapha kanye nokukwazi ukusindisa izimpilo, akulungile. Kubantu abaphikisana nocwaningo lwe-embryonic stem cell kuyindaba yokuziphatha kanye nokuziphatha okungaphezu kwezinto ezingokwesayensi.
Asikho isiqinisekiso sokuthi ukuqhubekela phambili ngokucwaninga kwe-stem cell cell kuzoveza imiphumela efunayo. Lokho, futhi, kuyinkinga kwabanye abaphikisayo. Ukusetshenziswa kwamaseli e-embryonic stem, kulesi sikhathi iphuzu, ngokungafani namaseli omuntu omdala abonise imiphumela yokwelapha.
Lapho Uqala khona
Ukuqonda le nkinga ngaphambi kokwenza umbono kubalulekile. Ucwaningo lwesitembu se-Stem luyinkinga eyinkimbinkimbi, ngaphandle kokungabaza. Uphenyo olwengeziwe mayelana nokubukwa kwesayensi nezokuziphatha lungenza kube nolwazi oluningi nolwazi, futhi isiqiniseko sokuthi umile eceleni kwenkinga enkulu kakhulu ehambisana nezinkolelo zakho.