Cau 25:Tbay hien tuong khang thuoc thu dc cua vk:

*Dn: khang thuoc la hien tuong vk gay benh k con nhay cam voi ksinh su dung (ksinh dieu tri k co hieu qua dvoi vk gay benh)

*Co che:

-tao enzyme fa huy ksinh. Vd: a-lactamase fa huy vong a-lactam cua ksinh nhom peni, acetyltranferase fa huy cloramphenicol

-Trao doi tinh tham cua mang NSC dvoi thuoc ksinh. Vd: vk trao doi tinh tham cua mang dvoi ksinh thuoc nhom polymycin, aminoglycosid

- vk trao doi ctruc ptu dich k cho thuoc bam vao. Vd: khang cephalosporin: trao doi PBPs, khang aminoglycosid: trao doi receptor

-Trao doi con duong chuyen hoa va lam mat tac dung cua thuoc. vd: khang sulfonamide: k su dung PABA de tong hop acid folic ma su dung chinh acid folic (.) mtruong

-Trao doi cac enzym lam enzyme lam enzyme van bao dam chuc nang chuyen hoa, tong hop , k bi mat tac dung boi khang sinh. Vd: khang quiralon = cach trao doi ctruc enzyme ADNgyrase

*nguon goc:

-k lien quan den di truyen

+vk song trong cac o viem man tinh co thanh day, xo hoa va ksinh k tiep xuc dc voi vk

+vk k co hoat dong chuyen hoa, k nhan len nhung k chet, ksinh k fat huy dc tac dung

+ vk mat ctruc dien hinh va thuoc k con tac dung

-Lien quan den di truyen: cac hien tuong dot bien gen, bien nap, tai nap, tiep hop, plasmid va transposom ( bien doi vat lieu di tryen

*Bien fap:

-chi dung ksinh de dtri cac benh nh. trung do vk gay ra

-chon ksinh theo ket qua ksinh do, uu tien ksinh fo hep, tac dung dac hieu

-dung ksinh dung chi dinh, du lieu luong va thoi gian

-tang cuong cong tac khu trung va tiet trung (.) bvien, tranh de lay truyen cac chung vk de khang

-lien tuc giam sat su de khang khang sinh cua vk

Cau 26: ksinh do la j?trbay nguyen li cua kthuat ksinh khuyech tan trong thach va ki thuat xdinh nong do MIC

*Dn: ksinh do la cac ki thuat thu nghiem tren invitro de xdinh do nhay cam voi thuoc ksinh cua vk, giup thay thuoc chon dc ksinh thich hop voi lieu luong ksinh thich hop de dtri cho cac b.nhan bi benh nh.trung do vk

*Nguyen li cua kt ksinh ktan (.) thach (ksinh do dinh tinh):

- Cac thuoc ksinh deu co kha nang khuyech tan tot trong mtruong thach

-Dug cac khoanh giay da tam ksinh khac nhau dat len be mat thach da fu 1 lop mong vk. Ksinh tu khoanh giay khuyech tan ra xquanh. Sau thoi gian nuoi cay, neu vk nhay cam voi ksinh ( xung quanh khoanh giay se co vung uc che vk, neu vk de khang ( k co vung uc che vk

*Kt xd nong do MIC: 1 luong vk can thu nhu nhau dc dua vao cac mtruong nhu nhau co ksinh dc fa loang dan theo bac 2. sau thoi gian nuoi cay, MIC la nong do ksinh o ong fa loang nhat ma k quan sat thay su ptrien cua vk, MIC la nong do ksinh nho nhat ma van co tac dung uc che su ptrien cua vk gay benh