When both genes were co - expressed in e. coli, the activity of ppsa varied from 2. 1 - 9. 1 fold comparing to control, but the activity of tkta was relatively stable ( 3. 9 - 4. 5 fold ). whatever the two genes were expressed respectively or cooperatively, both could promote the production of dahp, the first intermediate of the common aromatic pathway, but co - expression was more effective on forming dahp and screened ppt - and ptp - as more effective. the results demonstrate that co - expression of ppsa and tkta can improve the production of dahp, and what ' s more, when multigenes co - expressed, the recombinant which has coordinated enzymes activity is optimum
莽草酸途徑的最優化和整體調控基因csra的敲除正是上述改變的分子基礎,同時也為三種芳香族氨基酸的基因工程菌的構建打下了基礎; 7 .在國內外首次實現了共同途徑限制性
底物關鍵酶ppsa刁無『及arog與分支途徑關鍵酶基因phea的串聯高效表達,所構建的重組質粒ptga ,其ppsa 、 tkta 、 arog 、 cm和pd的酶活分別比對照提高了3 、 2 、 2 , 5 、 4 、 2 . 3倍,且其酶活比較協調一致; 8 .將ptga導入到
篩選的基因敲除和基因替換菌株大腸桿菌31884 c甲b中,搖瓶發酵證實比以往所構建的基因工程菌株具有較高的phe產量和糖轉化率率,分別為0 . 448 %和22 . 4 % 。
Due to the rapid progress of computer technology and development of image analysis technique, the fundus images could be processed, enhanced and analyzed both quantitatively and objectively
此系統更可以配合非散瞳式眼
底照相機,作為定期大量健康
篩檢或長期追蹤病程的工具。
You endured a thorough screening and made the cut
你經歷了一次徹
底的
篩查,最終勝出。
And grindintg experiment based on uniform design is conducted. depending on data process system, the regression model of production efficiency, output per degree and particle are established. through single factor analysis on all experimental indexes, the law that the bottom corner, height, bottom length of trapezium and spacing influence the hammer mill capbility are achieved
並採用均勻設計方法安排異型粉碎室粉碎試驗。利用數據處理系統,建立生產率、度電產量、粒度的回歸方程。對各試驗指標進行了單因素分析,研究梯形
篩片的
底角、高度、間距和下
底長對粉碎性能的影響規律。
Part 1 study on the antibiotic resistance of escherichia coil and klebsieua pneumoniae producing extended - spectrum beta - lactamases objective to investigate the prevalence of strains producing esbls among escherichia coil and klebsieua pneumoniae, look for the best detection substrate of these strains and determine the antibiotic resistance of them. methods 248 strains of e. coli. and 97 strains of k. pn from january to october, 2002 were investigated for production of extended - spectrum b - lactamases ( esbls ) by phenotypic screening and confirmatory test provided by the national committee for clinical laboratory standards ; compared the result of the phenotypic screening and confirmatory test to discuss the best detection substrate of these strains ; 16 kind of antibiotics were selected for antimicrobial susceptibility test for the resistance
方法對2002年1 ? 10月臨床分離的248株e . coli和97株k . pn ,採用美國臨床實驗室標準委員會( nccls )規定的esbls表型
篩選和確證試驗,確定本地區esbls的發生率;通過對不同
底物的初
篩結果與確證試驗結果的比較,探討本地區臨床檢測產esbls菌株的最佳
篩選
底物;選擇16種抗生素紙片做藥敏試驗,了解產esbls的e . coli和k . pn的耐藥性。
Cerebral spinal fluid fistulas of the anterior skull base lend themselves to an endoscopic approach. dissection begins with a meticulous anterior and posterior ethmoidectomy
前顱
底的腦脊液漏可以在鼻內窺鏡下進行處理,先小心翼翼的進行前後
篩竇組切除術,以暴露
篩頂全長。
Ball boxes are integrated underneath the screens. the ball boxes ensure efficient cleaning of the screens bby means of rubber balls
用於裝橡膠球的球箱集中安裝在
篩網下端/
底部。球箱的作用就是使得橡膠球不會往下掉,從而保證了
篩網的分離效果。
Screening surfaces ; woven filament cloth of silk or man - made fibers, dimensions
篩底.絲或化學纖維紡織布.尺寸
Sceening surfaces ; woven filament cloth of round man - made monofilaments, dimensions
篩底.人造單絲圓形紡織
篩網.尺寸
This machine is composed of the vertical vibration motor, a sieve bottom, a mesh frame, sieve room, rubber vibrating bowl, and all fastening pieces etc
該機由立式激振電機、篩底、網架、篩粉室、橡膠振蕩碗等各緊固件組成一體。