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101.
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Direct estimation of biofilm density on different pipe material coupons using a specific DNA-probe 总被引:3,自引:0,他引:3
Chang YC Le Puil M Biggerstaff J Randall AA Schulte A Taylor JS 《Molecular and cellular probes》2003,17(5):237-243
A variety of approaches to quantify biomass in biofilms without disruption due to detachment have been developed over the years. One basic approach is the combination of advanced microscopy with molecular staining. However, many stains (e.g. 4',6-diamino-2-phenylindole, acridine orange or live-dead stains) can be non-specific when corrosion products, precipitates, and pipe material are present. In addition, some pipe materials cause high background when using epifluorescent microscopy. The new refinement discussed in this presentation used fluorescence spectroscopy to obtain the spectra from four common distribution system pipe materials: PVC, 'concrete' lined cast iron, cast iron, and galvanized steel. The emission maximum for all four materials was between 500 and 550 nm, but emissions radically decreased around 575-600 nm. A molecular probe, BO-PRO-3 (Molecular Probes, Inc., Eugene, OR, USA) was identified which has an emission intensity maximum at 599 nm (red), with emission intensity 200 times greater when it is bound to DNA. The BO-PRO-3 has greatly reduced non-specific staining and background problems. In the preliminary experiment, using diluted waste water, a significant exponential relationship was found between stained surface area/total area ratio and fixed biofilm inventory measurements from scraping heterotrophic plate counts (SHPC) on R2A medium. In addition, the biofilm inventory on different pipe material coupons from pilot distribution systems was also correlated to the stained surface area fraction and SHPC. 相似文献
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Chang Mook Park Kang Young Choi Sung Jae Heo Jung-Soo Kim 《The British journal of oral & maxillofacial surgery》2014
Inadvertent retention of surgical gauze during an operation can have disastrous consequences for both the patient and the surgeon. Several cases have been reported, particularly after abdominal surgery. However, it has never to our knowledge been reported as a leading cause of dysfunction of the Eustachian tube after orthognathic surgery. We recently encountered a patient in whom it presented with unilateral otitis media with an effusion after orthognathic surgery. All surgeons involved with orthognathic surgery should be aware that remnants of surgical gauze after orthognathic surgery can compromise the Eustachian tube and cause otitis media with an effusion. 相似文献
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Jai Gon Seo Sang-Hee Choi Sulkyoung Shin Byung Hoon Lee Moon Jong Chang 《The Journal of arthroplasty》2014
We sought to determine the relationship between the mechanical axis-derived and the anatomic landmark-derived femoral rotational axes using three dimensional computed tomographic images of 20 lower extremities. The mechanical axis-derived femoral rotational axis was created on the distal articular surface of the femur using coronal mechanical limb axis and the reconstructed images of the femur. Then, we measured the angular difference between mechanical axis-derived and anatomic landmark-derived femoral rotational axes. The mechanical axis-derived femoral rotational axis was externally rotated with a mean of 2.2° (range, 0 to 4.7°; SD, 1.0) compared with the surgical epicondylar axis. Our findings should be considered to obtain a proper femoral rotational axis in total knee arthroplasty. 相似文献
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Ching-Chung Liang Yi-Hao Lin Tse-Ching Chen Shuenn-Dhy Chang 《International urogynecology journal》2014,25(8):1105-1113