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We cared for a patient with methicillin-resistant Staphylococcus aureus bacteremia who experienced clinical failure with daptomycin. The failure was accompanied by progressive elevation of the daptomycin minimum inhibitory concentration during treatment. DNA fingerprinting confirmed that the minimum inhibitory concentration elevation occurred within the same strain of methicillin-resistant Staphylococcus aureus. This observation provides important new information to clinicians who adopt this promising drug for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus.  相似文献   
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Mycobacterial strains from the Mycobacterium avium complex were compared with each other and with Mycobacterium phlei isolates by restriction endonuclease digestion of chromosomal DNA with SspI and analysis by pulsed-field gel electrophoresis. Characteristic profiles were observed for known typed strains, and five groups were identified. Primary bovine isolates identified as Mycobacterium paratuberculosis by classical methods were shown to fall into both the M. paratuberculosis- and M. avium-like groups. M. paratuberculosis 18 was in the latter category. Two Mycobacterium intracellulare strains of different Schaefer serotypes had different digestion profiles. In addition, this system was exploited for the preparation of DNA probes by the isolation, digestion, and subcloning of DNA fragments separated by pulsed-field gel electrophoresis. Probe JC12 hybridized only to M. avium complex strains, but not to M. phlei, showing characteristic hybridization profiles for each of the groups previously identified by pulsed-field gel electrophoresis. The approach taken in the study lends itself to the comparative analysis of members of the M. avium complex and to the isolation and characterization of DNA probes with specificity for these mycobacteria.  相似文献   
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The expression of somatostatin receptors 1 and 2 in benign, pre‐malignant and malignant laryngeal lesions The role of chemotherapy in squamous cell carcinoma of the larynx has not been clearly defined. Whilst toxic chemotherapy regimes may confer a marginal improvement in survival, surgery and radiotherapy remain the mainstay of treatment. Somatostatin is a naturally occurring peptide, which exerts antiproliferative and antiangiogenic effects via five membrane‐bound receptor subtypes. The expression of somatostatin receptor subtypes (SSTRs) 1 and 2 was studied in benign, pre‐malignant and malignant laryngeal specimens. Epithelial expression of SSTR1 was detected in 4/6 (67%) Reinke's oedema, 5/6 (83%) pre‐malignant and 8/12 (67%) malignant specimens, with virtually no stromal or vascular expression. High levels of epithelial SSTR2 expression were noted in all Reinke's oedema specimens, compared with low‐to‐moderate levels in only 2/6 (33%) pre‐malignant and 3/12 (25%) malignant specimens (P < 0.01). This ‘loss’ of epithelial SSTR2 expression may provide a growth advantage in pre‐malignant and malignant laryngeal lesions. Vascular expression of SSTR2 was ubiquitous in all groups, with scant stromal expression. Overall, most (>80%) pre‐malignant and malignant laryngeal specimens expressed at least one of the two SSTR subtypes studied. Somatostatin analogues may have a therapeutic role in squamous cell carcinoma of the larynx.  相似文献   
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Postpylorus delivery of enteral feeding is perceived by many experts to be safer than intragastric delivery. To test this assumption, patients with similar Glasgow Coma Scores were given identical enteral formulas continuously via a 10-French nasoenteric tube, placed into the stomach or beyond the second portion of the duodenum. Observations were made for attainment of desired nutrition, bowel changes, and clinical signs of aspiration. Radiographs of the chest and abdomen were obtained every 3 days. If a tube migrated out of a chosen location, it was replaced. Thirty-three patients were studied. Seventeen patients were fed into the stomach and 16 patients were fed postpylorus. The mean duration of enteral feeding was 11.8 days for the gastric group and 10.9 days for the postpylorus group (p = NS). The time to deliver the desired kilocalories was 3.33 and 2.77 days (p = NS) for gastric and postpylorus-fed patients. Tubes displaced similarly in each group, gastric 0.647, postpylorus 0.750 per duration of feeding (p = NS). Chest radiographs met the criteria for aspiration pneumonia in 31.3% of gastric and 40% of postpylorus-fed patients (p = NS). Together, these data indicate that complications from enterally fed patients are equally common whether the distal port of the feeding tube is in the stomach or beyond the second portion of the duodenum.  相似文献   
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