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771.
Photophysical phenomena associated with carbon nanoparticles in combination with biocompatibility and readily functionalizable properties have attracted significant interest for sensing and imaging applications. A potassium ion optode based on the fluorescence quenching of carbon quantum dots (CQDs) was constructed. The CQDs were synthesized using a microwave method, citric acid and 2,2′‐(ethylene‐dioxy)bis(ethylamine). A quantum yield of 7.1% was calculated for the synthesized CQDs. A linear dynamic range of about one‐order of magnitude with a correlation coefficient of 0.99 was obtained. The optode was applied on real samples and a 0.60–1.60% error range was obtained relative to the ion‐selective electrode. 相似文献
772.
773.
Fouad A.K. El-Zaatari Saleh A. Naser Kristina Hulten Paula Burch David Y. Graham 《Current microbiology》1999,39(2):115-119
Recent data using improved cultural, molecular, and serological techniques have strengthened the association of Mycobacterium paratuberculosis with Crohn's disease, an inflammatory bowel disease (IBD) with unknown etiology. To provide more evidence of an etiological
association, antibody reactivities of Crohn's disease patients were tested by immunoblotting against M. paratuberculosis–recombinant antigens. A clone containing a 1,402-bp insert and expressing a 36K-antigen (p36) was analyzed. No homology was
found between the deduced amino acid sequence of p36 and any protein sequences compiled in the GenBank indicating that p36
is a novel mycobacterial protein. The reactivity of 199 serum samples was tested against the p36 by immunoblotting technique.
Sera from 77 of 89 (86.5%) Crohn's disease patients and 16 of 18 (89%) sera from patients with tuberculosis and leprosy reacted
with p36 compared to 5 of 42 (12%) ulcerative colitis and non-IBD control sera (p < 0.0001). In addition, p36 reacted to all
sera from 10 normal controls that were Bacillus Calmette-Guerin (BCG)-immunized and only to 10% of 40 normal controls that were not BCG-immunized. The fact that sera from Crohn's disease
patients reacted to p36 with the same high frequency as the sera from patients that were exposed to mycobacterial antigens
further supports the hypothesis of the mycobacterial etiology in Crohn's disease.
Received: 8 January 1998 / Accepted: 18 March 1999 相似文献