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21.
Joon Myong Song 《Analytica chimica acta》2003,487(1):75-82
In this work, a combination of complementary metal-oxide semiconductor (CMOS) microchip system with capillary array electrophoresis (CAE) is demonstrated as a system for optimizing conditions for enzymatic reaction. Dimethylacridinone (DDAO)-phosphate substrate and alkaline phosphatase conjugate were selected for the enzymatic reaction, which was applicable to the enzyme-linked immunosorbent assay (ELISA) technique. Laser-induced fluorometry with a miniature semiconductor laser was used to detect the enzymatic products. The speed of the enzymatic reaction between the DDAO-phosphate and the alkaline phosphatase conjugate was investigated as a function of reaction time. The microchip-CAE detection system could determine the pH condition and the concentration of enzyme that are suitable for rapid and low-cost analysis. This result shows the feasibility of using the microchip-CAE system for application to miniaturized screening systems. 相似文献
22.
Kang K Bae SJ Kim WM Lee DH Cho U Lee MH Lee MS Nam S Kuettner KE Schwartz DE 《Experimental & molecular medicine》2000,32(3):146-154
Nonsteroidal antiinflammatory drugs(NSAIDs) are known as clinically effective agents for treatment of inflammatory diseases. Inhibition of cyclooxygenase has been thought to be a major facet of the pharmacological mechanism of NSAIDs. However, it is difficult to ascribe the antiinflammatory effects of NSAIDs solely to the inhibition of prostaglandin synthesis. Human neutrophil elastase (HNElastase; HNE, EC 3.4.21.37) has been known as a causative factor in inflammatory diseases. To investigate the specific relationship between HNElastase inhibition and specificity of molecular structure of several NSAIDs, HNElastase was purified by Ultrogel AcA54 gel filtration, CM-Sephadex ion exchange, and HPLC (with TSK 250 column) chromatography. HNElastase was inhibited by aspirin and salicylate in a competitive manner and by naproxen, ketoprofen, phenylbutazone, and oxyphenbutazone in a partial competative manner, but not by ibuprofen and tolmetin. HNElastase-phenylbutazone-complex showed strong Raman shifts at 200, 440, 1124, 1194, 1384, 1506, and 1768 cm(-1). The Raman bands 1194, 1384, and 1768 cm(-1) may represent evidences of the conformational change at -N=N-phi radical, pyrazol ring, and -C=O radical of the elastase-drug complex, respectively. Phenylbutazone might be bound to HNElastase by ionic and hydrophobic interaction, and masked the active site. Inhibition of HNElastase could be another mechanism of action of NSAIDs besides cyclooxygenase inhibition in the treatment of inflammatory diseases. Different inhibition characteristics of HNE-lastase by NSAIDs such as aspirin, phenylbutazone-like drugs and ineffective drugs could be important points for drawing the criteria for appropriate drugs in clinical application. 相似文献
23.
Balest R Cho K Ford WT Lohner M Park H Rankin P Smith JG Alexander JP Bebek C Berger BE Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Dickson M Drell PS Dumas DJ Ehrlich R Elia R Gaidarev P Garcia-Sciveres M Gittelman B Gray SW Hartill DL Heltsley BK Henderson S Jones CD Jones SL Kandaswamy J Katayama N Kim PC Kreinick DL Lee T Liu Y Ludwig GS Masui J Mevissen J Mistry NB Ng CR Nordberg E Patterson JR Peterson D Riley D Soffer A Avery P Freyberger A Lingel K Prescott C 《Physical review letters》1995,75(21):3809-3813
24.
Artuso M Gao M Goldberg M He D Horwitz N Moneti GC Mountain R Muheim F Mukhin Y Playfer S Rozen Y Stone S Xing X Zhu G Bartelt J Csorna SE Egyed Z Jain V Gibaut D Kinoshita K Pomianowski P Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Würthwein F Asner DM Athanas M Bliss DW Brower WS Masek G Paar HP Gronberg J Korte CM Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Roberts D Ryd A Tajima H Witherell MS Balest R Cho K 《Physical review letters》1995,75(5):785-789
25.
Barish B Chadha M Chan S Cowen DF Eigen G Miller JS O'Grady C Urheim J Weinstein AJ Acosta D Athanas M Masek G Paar HP Gronberg J Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Qiao C Richman JD Ryd A Tajima H Sperka D Witherell MS Procario M Balest R Cho K Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Bloom K Browder TE Cassel DG Cho HA Coffman DM Crowcroft DS Drell PS Ehrlich R Gaidarev P Galik RS Garcia-Sciveres M Geiser B 《Physical review D: Particles and fields》1995,51(3):1014-1033
26.
W. D. Wu A. Keren L. P. Le G. M. Luke B. J. Sternlieb Y. J. Uemura D. C. Johnston B. K. Cho P. Gehring 《Hyperfine Interactions》1994,86(1):615-621
Muon spin relaxation (SR) studies have been performed in the normal spinel LiTi2O4 and the A-15 superconductor V3Si to measure the magnetic penetration depth . The relaxation rate(T) 1/2 in field-cooled measurements shows a sharp increase belowT
c
followed by saturation at low temperatures in both systems. This feature implies an isotropic energy gap without anomalous zeros, and most likelys-wave pairing. The low temperature penetration depth (T 0) is determined to be 2100Å for LiTi2O4 and 1300Å for V3Si respectively. Assuming a clean limit relation –2 n
s
/m
*, we derive the Fermi temperatureT
F
n
s/
2/3
m
* from the relaxation rate and the Sommerfeld constant asT
F
3/4–1/4. Unlike conventional superconductors, both LiTi2O4 and V3Si have a large ratio ofT
c
/T
F
0.01, only slightly smaller than those ratios in more exotic superconductors.We thank C. Ballard and K. Hoyle for technical assistance. Work at Columbia University is supported by NSF Grant No. DMR-89-13784 and Packard Foundation (YJU). Ames Laboratory is operated for the U. S. Department of Energy by Iowa State University under Contract No. W-7405-Eng-82. Work at Ames was supported by the Director for Energy Research, Office of Basic Energy Sciences. 相似文献
27.
Acosta D Athanas M Masek G Paar H Bean A Gronberg J Kutschke R Menary S Morrison RJ Nakanishi S Nelson HN Nelson TK Richman JD Ryd A Tajima H Schmidt D Sperka D Witherell MS Procario M Yang S Balest R Cho K Daoudi M Ford WT Johnson DR Lingel K Lohner M Rankin P Smith JG Alexander JP Bebek C Berkelman K Besson D Browder TE Cassel DG Cho HA Coffman DM Drell PS Ehrlich R Galik RS Garcia-Sciveres M Geiser B Gittelman B Gray SW Hartill DL Heltsley BK Jones CD Jones SL Kandaswamy J Katayama N Kim PC 《Physical review D: Particles and fields》1994,49(11):5690-5700
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