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741.
A new Doppler probe inside a needle was evaluated in a group of infants and children to assess its suitability for subclavian venous access. While the efficient use of this device required learning a new technique, we found the device useful to accurately locate the subclavian vein and differentiate it from the artery in all patients weighing more than 3 kg. This device will be most helpful in cases of difficult access, eg, scar from previous access, obesity, or edema.  相似文献   
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BACKGROUND: This study uses wrist actigrapy to assess the effects of 24-hr transdermal nicotine replacement on the sleep and daytime activity of smokers during smoking cessation. METHODS: Seventy-one subjects grouped as light (n = 23), moderate (n = 24), or heavy (n = 24) smokers were randomly assigned to placebo or 11, 22, or 44 mg/day doses of transdermal nicotine for 1 week of intensive inpatient treatment of nicotine dependence. Outpatient patch therapy continued for 7 weeks following the inpatient stay. Those initially on placebo were randomly assigned to 11 or 22 mg/day, and those initially on 44 mg/day were reduced to 22 mg/day at Week 4. RESULTS: There was a significant decrease in daytime wrist activity during patch therapy and the 1st week off patch therapy. These changes in daytime wrist activity were positively correlated with percentage of nicotine and cotinine replacement. No changes from baseline in sleep (sleep efficiency or wrist activity) were detected, nor were there differences in sleep among the four patch doses. CONCLUSIONS: Using wrist actigraphy, this study failed to show any disturbing effects of 24-hr high-dose nicotine replacement on sleep. Lower levels of nicotine replacement were associated with a decrease from baseline in daytime wrist activity.  相似文献   
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NADPH oxidase     
The antimicrobial activities of insoluble halogenated acetamidomethy1-styrene polymers (prepared by covalent bonding of iodine to polystyrene) were assessed as were the factors determining antimicrobial efficacy. The most active materials were selected from chlorinated or iodinated polymers. Antimicrobial activities were assessed for Escherichia coli (ATCC 25922; American Type Culture Collection, Rockville, MD, U.S.A.), Saccharomyces cerevisiae, and Candida albicans by determining time-course changes in microbial counts in vitro. A 2-iodoacetamidomethylstyrene polymer (No.6-I:-CH2I) was found to have the greatest antimicrobial activity against both bacteria and fungi. No.6-I is the first antimicrobial material that did not make an inhibition hollow in the conventional diffusion test or for which conjugated iodine showed antibacterial activity. This material can be introduced into styrene units on the surface of devices by chemical modification. This material was most active at 37 degrees C. For coated dishes, antimicrobial activity depended on the depth or swollen character of the reactive layer. NO.6-I requires not only a minimum width of polymer layer, but also frequent contact with microbes to have an antimicrobial effect. No.6-I is valuable as a new material because it has strong antimicrobial activity by itself but does not release active iodine. This material is expected to have various applications in implantable clinical devices.  相似文献   
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