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81.
Patients with severe burns are susceptible to infection with Gram-positive organisms including methicillin-resistant Staphylococcus aureus, and often require higher antibiotic dosages compared with other patients. This study examined the pharmacokinetics of a single iv dose of teicoplanin (12 mg/kg) in 15 adults and five children with severe burns. Adults were aged 21-82 years with a median total body surface area (TBSA) burn of 30% (range 15-60%). Children were aged 10 months-l0 years with median TBSA burn of 15% (10-30%). At 12 h, the median serum teicoplanin concentration was 12.8 mg/L (9.027.1 mg/L) in adults and 7.6 mg/L (6.6-l0.8 mg/L) in children, (P < 0.01); at 24 h, the corresponding values were 8.3 mg/L (4.6-l2.9 mg/L) and 5.2 mg/L (4.2-6.0 mg/L). Using a three-compartment model, the median terminal half life in adults was 114 h (47-278 h). Children fitted a two-compartment model with a terminal half-life of 38 h (2l-41 h). The median concentration of teicoplanin in fluid from the burn wound was 60% of the serum antibiotic concentration. A single iv dose of 12 mg/kg of teicoplanin was sufficient to produce therapeutic serum concentrations in burn patients for 24 h, but monitoring of antibiotic levels in serum may be advisable in those with high total clearance, especially children.  相似文献   
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Ophthalmology     
It is estimated that 49% to 74% of cases of contact lens-associated ulcerative keratitis could be prevented by eliminating overnight wear. Heavy alcohol consumption appears to be associated with all types of cataracts. Cigarette smokers have a nearly threefold greater risk of developing age-related macular degeneration than nonsmokers.  相似文献   
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The chromosome localization of human HOX gene clusters has been reinvestigated by fluorescence in situ hybridization (FISH). Three loci were precisely localized in 7p15.3 (HOXA@), 17q21.3 (HOXB@) and 12q13.3 (HOXC@). The localization of HOXD@ was confirmed to 2q31.  相似文献   
86.
Using the cis-acting human cytomegalovirus (HCMV) packaging elements (pac 1 and pac 2) as DNA probes, specific DNA-protein complexes were detected by electrophoretic mobility shift assay (EMSA) in both HCMV-infected cell nuclear extracts and recombinant baculovirus-infected cell extracts containing the HCMV p130 (pUL56) protein. DNA-binding proteins, which were common in uninfected and infected cell extracts, were also detected. Mutational analysis showed that only the AT-rich core sequences in these cis-acting motifs, 5'-TAAAAA-3' (pac 1) and 5'-TTTTAT-3' (pac 2), were required for specific DNA-protein complex formation. The specificity of the DNA-protein complexes was confirmed by EMSA competition. Furthermore, a specific endonuclease activity was found to be associated with lysates of baculovirus-infected cells expressing recombinant p130 (rp130). This nuclease activity was time dependent, related to the amount of rp130 in the assay, and ATP independent. Nuclease activity remained associated with rp130 after partial purification by sucrose gradient centrifugation, suggesting that this activity is a property of HCMV p130. We propose a possible involvement of p130 in HCMV DNA packaging.  相似文献   
87.
What are the relative roles of imitation, improvisation and invention in the development of large song repertoires in species of the songbird family Mimidae? This question was addressed in a laboratory study of the vocal development of young grey catbirds, Dumetella carolinensiscollected from western Massachusetts. Two groups heard a repeated 10-s, tape-tutored segment of catbird song, two other groups heard a repeated 16-min segment and a fifth group heard no tape-tutored songs. One male selected for study from each group developed a large repertoire of seemingly normal songs, and wild males responded strongly to songs of the male that had heard no tape-tutored song. Relying little on precise imitation and largely on improvising or inventing, each male developed a highly unique repertoire. A geographical survey of catbird song revealed little to no evidence of song sharing or microgeographical variation, which is consistent with the idea that imitation plays a relatively minor role in song development. Perhaps simultaneous selection for large repertoires and reduced geographical variation has led to such an emphasis on song individuality and non-imitative developmental processes.  相似文献   
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BACKGROUND & AIMS: Currently available Helicobacter pylori models show variable and, in some instances, poor colonization. There is a need for a strain with high colonizing ability to act as a standard for animal studies. METHODS: After screening a range of fresh clinical isolates and long-term adaptation in mice, a strain of H. pylon has been isolated with a very good colonizing ability. RESULTS: This strain, named the Sydney strain of H. pylori (strain SS1), is cagA and vacA positive. High levels of colonization (10(6)-10(7) colony-forming units/g tissue) were achieved consistently in C57BL/6 mice. Colonization levels varied depending on the mouse strain used with BALB/c, DBA/2, and C3H/He, all being colonized but in lower numbers. In all strains of mice, bacteria were clearly visible at the junctional zone between the antrum and the body. The phenotype was stable with colonizing ability remaining after 20 subcultures in vitro. The bacterium attached firmly to gastric epithelium. During 8 months, a chronic active gastritis slowly developed, progressing to severe atrophy in both C57BL/6 and BALB/c mice. CONCLUSIONS: The Sydney strain of H. pylori is available to all and will provide a standardized mouse model for vaccine development, compound screening, and studies in pathogenesis.  相似文献   
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