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851.
Enterotoxin production by Staphylococcus species other than Staphylococcus aureus has been reported. Staphylococcus strains (104 in toto) representing twelve species and subspecies were examined for enterotoxins using a commercial staphylococcal enterotoxin ELISA immunoassay (TECRA, International Bioproducts). Staphylococcus intermedius (24 strains) and S. aureus (7 strains) were positive with this test. Western blots of S. aureus exoproteins demonstrated proteins of approximately 30 kD, consistent with known staphylococcal enterotoxins. The major antigen in all S. intermedius strains, a 75 kD protein, was not analogous to previously described staphylococcal enterotoxins. This protein was unique to S. intermedius. Gel filtration data indicate that the protein is a subunit of a larger protein in vivo. The 75 kD protein cross-reacts with several enterotoxin antibodies. It is unclear whether the protein is a toxin, but its homology with S. aureus enterotoxins may indicate a shared toxic region, or this protein may create false positive results in screening for enterotoxin. 相似文献
852.
F Cetta RH Feldt PW O'Leary DD Mair CA Warnes DJ Driscoll DJ Hagler CJ Porter KP Offord HV Schaff FJ Puga GK Danielson 《Canadian Metallurgical Quarterly》1996,28(2):480-486
OBJECTIVES: This study sought to evaluate changes in early morbidity and mortality as well as predictors of outcome in our most recent 339 patients undergoing modified Fontan operations. BACKGROUND: The Fontan operation is the preferred definitive palliation for patients with functional single ventricles. Previously reported early mortality rates after Fontan operation have been substantial. METHODS: Records of 339 consecutive patients who had a Fontan operation at the Mayo Clinic between 1987 and 1992 (recent cohort) were reviewed. This cohort was compared with the previous 500 patients who had Fontan operations performed between 1973 and 1986 (early cohort). RESULTS: Recently, overall early mortality after Fontan has decreased significantly compared with that for the early cohort (from 16% to 9%, p = 0.002). This decline occurred despite increased anatomic complexity of patients. Short-term posthospital survival has also improved significantly in recent patients. One-year survival improved to 88% from 79%, and 5-year survival to 81% from 73% (p = 0.006). Patients with common atrioventricular valves and those who took daily preoperative diuretic medication or had either postoperative renal failure or elevated postbypass right atrial pressure were at increased risk for early mortality. Young age was not found to be a risk factor for early mortality. Early mortality for patients with heterotaxia decreased dramatically: recent 30-day mortality was 15% compared with 41% in the early heterotaxy cohort. CONCLUSIONS: Many factors may have contributed to decreased early mortality after Fontan. Improved patient selection, younger age at time of operation, refinements in surgical techniques and postoperative management may all have had important roles. Proposed technical modifications of the Fontan operation must be evaluated in light of these improved results. 相似文献
853.
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
854.
TD Wolter PJ Hauri DR Schroeder JA Wisbey IT Croghan KP Offord LC Dale RD Hurt 《Canadian Metallurgical Quarterly》1996,25(5):601-610
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