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961.
962.
AJ Singer CT Coby AH Singer HC Thode GT Tortora 《Canadian Metallurgical Quarterly》1999,38(3):194-196
Low frequency ultrasound (LFUS) significantly enhances skin permeability to a variety of drugs; however, its bacterial effects have not been well studied. Staphylococcus epidermidis organisms were grown and standardized to 10(5) cfu/ml 24 h prior to investigation and suspended in normal saline. LFUS was applied with two probes immersed in the bacterial suspensions over a range of suspension volumes, intensities, and exposure times. The suspension temperature was measured, and a sample was removed, streaked onto blood agar plates, and incubated at 37 degrees C for 24 h. Quantitative bacterial counts were then obtained. LFUS resulted in significant reductions in bacterial counts that correlated with fluid temperature. Probe size and ultrasound intensity appeared to affect bacterial counts, but were also correlated with temperature. Bacterial growth was minimal with temperatures exceeding 45 degrees C. While LFUS can reduce bacterial counts, these conditions have the potential to cause burns in humans. 相似文献
963.
MM Schneider JC Borleffs RP Stolk CA Jaspers AI Hoepelman 《Canadian Metallurgical Quarterly》1999,353(9148):201-203
BACKGROUND: Prophylactic drugs for Pneumocystis carinii pneumonia (PCP) are strongly recommended for HIV-1-infected patients with CD4 cell counts of less than 200 cells/microL. Because of the highly active antiretroviral therapy (HAART) currently available, we speculated that prophylaxis can be discontinued in patients with CD4 cell counts of more than 200 cells/microL. METHODS: In this prospective observational study, PCP prophylaxis (primary or secondary) was discontinued in HIV-1-infected patients whose CD4 cell count had increased above 200 cells/microL (documented twice with an interval of at least 1 month) as a result of HAART. Patients and their CD4 cell counts were monitored every 3 months. The primary endpoint of the study was the occurrence or reoccurrence of PCP. FINDINGS: 78 patients were enrolled: 62 patients were receiving prophylaxis for primary prevention of PCP and 16 patients for secondary prevention of PCP. At the time of discontinuation of prophylaxis, the mean CD4 cell count was 347 cells/microL, and HIV-1-RNA was not detectable in 61 patients. The lowest mean CD4 cell count during prophylaxis was 79 cells/microL. Patients stopped prophylaxis 9.8 (SD 6.4) months after they started HAART. The mean follow-up after discontinuation of prophylaxis was 12.7 (SD 7.6) months, and none of the patients developed PCP (97.5% one-sided CI 0-4.4%). INTERPRETATION: The preliminary results of this study indicate that PCP prophylaxis can be stopped safely in HIV-1-infected patients whose CD4 cell counts have increased above 200 cells/microL after treatment with HAART. 相似文献
964.
JK Barnett D Barnett CA Bolin TA Summers EA Wagar NF Cheville RA Hartskeerl DA Haake 《Canadian Metallurgical Quarterly》1999,67(2):853-861
The outer membrane of pathogenic Leptospira species grown in culture media contains lipopolysaccharide (LPS), a porin (OmpL1), and several lipoproteins, including LipL36 and LipL41. The purpose of this study was to characterize the expression and distribution of these outer membrane antigens during renal infection. Hamsters were challenged with host-derived Leptospira kirschneri to generate sera which contained antibodies to antigens expressed in vivo. Immunoblotting performed with sera from animals challenged with these host-derived organisms demonstrated reactivity with OmpL1, LipL41, and several other proteins but not with LipL36. Although LipL36 is a prominent outer membrane antigen of cultivated L. kirschneri, its expression also could not be detected in infected hamster kidney tissue by immunohistochemistry, indicating that expression of this protein is down-regulated in vivo. In contrast, LPS, OmpL1, and LipL41 were demonstrated on organisms colonizing the lumen of proximal convoluted renal tubules at both 10 and 28 days postinfection. Tubular epithelial cells around the luminal colonies had fine granular cytoplasmic LPS. When the cellular inflammatory response was present in the renal interstitium at 28 days postinfection, LPS and OmpL1 were also detectable within interstitial phagocytes. These data establish that outer membrane components expressed during infection have roles in the induction and persistence of leptospiral interstitial nephritis. 相似文献
965.
An uncommon reaction to varicella vaccine has been urticaria. Based on two reports of urticaria believed to be due to gelatin in recipients of measles-mumps-rubella vaccine, we suspected gelatin as the cause of generalized urticaria in two children after varicella vaccination. Intradermal testing with gelatin yielded a wheal and flare reaction in both children. We conclude that children known to be allergic to gelatin should not receive Oka/Merck varicella vaccine (VARIVAX). 相似文献
966.
Considerable progress has been made recently in the production of metallic foams. Scale up has progressed so far that widespread commercial use may become a reality in the near future. In this review the merits of the various fabrication techniques are highlighted, while particular emphasis is placed on the demands of the various applications and the suitability of each process to meet these demands. 相似文献
967.
968.
The relationship between friction, wear, and transfer films of three metal carbide-reinforced amorphous carbon coatings (TiC/a:C,
TiC/a:C–H, and WC/a:C–H), sometimes referred to as metal-doped diamond-like carbon coatings, has been investigated. Tribological
tests were performed in an in situ tribometer with sapphire or steel hemispheres run against coated flats in dry or ambient
air. The sliding contact interface was observed and recorded by optical microscopy during reciprocating sliding tests. The
friction and wear behavior during run-in depended on the number of sliding cycles to form a stationary transfer film on the
hemisphere. Stationary transfer films formed rapidly (within ten cycles) and the friction coefficient fell to 0.2 (ambient
air) or 0.1 (dry air), except with sapphire against WC/a:C–H in dry air; with the latter, a stationary transfer film required
nearly 100 cycles to form, during which the friction remained high and the wear rate was from 10 to 100 times higher than
the other two coatings. For all coatings, three velocity accommodation modes (VAM) were observed from run-in to steady-state
sliding and were correlated with the friction and wear behavior. The delayed adherence of the transfer film to sapphire from
WC/a:C–H coatings in dry air is discussed in terms of equilibrium thermochemistry. Friction and wear behavior during run-in,
therefore, depended on transfer film adherence to the hemisphere and the VAM between transfer films and the coating. 相似文献
969.