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51.
Dislodgment of an atrial screw-in pacing lead is quite rare. This report describes a rare case of an atrial screw-in lead dislodgment 10 years after implantation. Although it is an uncommon complication, very late dislodgment can occur postoperatively, and careful follow-up is necessary.  相似文献   
52.
BACKGROUND: Bronchoalveolar lavage (BAL) is an established technique for measuring antibiotic concentrations in the epithelial lining fluid (ELF) of the bronchiolar and alveolar regions; however, the results may not reflect concentrations in bronchial regions. Bronchoscopic microsampling (BMS) is a technique that makes it possible to obtain multiple samples from bronchial ELF. OBJECTIVE: BMS and BAL were used to analyze the pharmacokinetics of gatifloxacin in bronchial ELF from healthy young adult subjects and adult patients with chronic bronchitis. METHODS: Bronchial ELF samples were obtained by BMS at 1, 2, 3, 4, 6, 10, and 24 hours after administration of a single oral dose of gatifloxacin 200 mg in healthy young adult (aged 20-25 years) subjects, and at 1, 2, 4, and 10 hours after a single dose in patients with chronic bronchitis (aged > or =20 years). At least 1 month after the initial BMS, alveolar (BAL) and bronchial (BMS) ELF samples were obtained from another group of healthy subjects 2 hours after administration of a single oral dose of gatifloxacin 200 mg for comparison of gatifloxacin concentrations in samples obtained by the 2 techniques. RESULTS: Bronchial ELF samples were obtained from 8 healthy subjects and 5 patients with chronic bronchitis; alveolar ELF samples were obtained from a separate group of 5 healthy subjects. For the healthy subjects, the mean (SD) AUC(0-24) in serum and bronchial ELF, corrected for mg/kg doses, was 4.6 (1.1) and 7.6 (3.5) mg x h/L, respectively. In the patients with chronic bronchitis, the AUC(0-10) in serum and bronchial ELF, corrected for mg/kg doses, was 3.9 (0.8) and 4.1 (1.5) mg x h/L. The C(max) in serum and bronchial ELF, corrected for mg/kg doses, was 0.6 (0.2) and 1.4 (0.8) mg/L in healthy subjects and 0.7 (0.2) and 0.7 (0.2) mg/L in patients with chronic bronchitis. In healthy subjects, the C(max) and AUC(0-24) were significantly higher in bronchial ELF than in serum (both, P < 0.05). Gatifloxacin concentrations were significantly lower in bronchial ELF obtained by BMS than in alveolar ELF obtained by BAL (P < 0.05). CONCLUSIONS: Based on the findings of this study in small numbers of healthy young adult volunteers and patients with chronic bronchitis, BMS appears to be a promising method for measuring drug concentrations and determining the pharmacokinetic profile of gatifloxacin in bronchial ELF. Additional studies are needed to correlate measured concentrations obtained by BMS with clinical and/or microbiologic outcomes in larger populations.  相似文献   
53.
Mast cell-derived prostaglandin D(2) (PGD(2)) is one of the essential modulators of eosinophilic airway inflammation in asthma and allergic rhinitis. Two G protein-coupled receptors for PGD(2), prostaglandin D(2) receptor (DP) and chemoattractant receptor-homologous molecule expressed on Th(2) cells (CRTH2), are both expressed on the surface of eosinophils, and CRTH2 has been demonstrated to mediate PGD(2)-induced eosinophil mobilization in vitro. However, it has not yet been determined whether PGD(2) and its receptors mediate in vivo eosinophil trafficking into the airways or other organs. We demonstrated that intratracheal administration of PGD(2) in rats pretreated with systemic interleukin-5 (IL-5) injection induced marked airway eosinophilia, determined by the differential counts of cells in bronchoalveolar lavage (BAL) fluid and lung histology, within 2 h. Systemic IL-5 alone significantly increased the number of eosinophils in the peripheral blood but showed no effect on airway eosinophilia. Three CRTH2-specific agonists (13,14-dihydro-15-keto-PGD(2), 11-deoxy-11-methylene-15-keto-PGD(2), and indomethacin) demonstrated equivalent induction of BAL eosinophilia to that of PGD(2), but a DP agonist (BW 245C [5-(6-carboxyhexyl)-1-(3-cyclohexyl-3-hydroxypropyl)-hydantoin]) or a thromboxane A(2) receptor (TP) agonist ([1S-1alpha,2beta(5Z), 3alpha(1E,3R*),4alpha)]-7-[3-(3-hydroxy-4-(4'-iodophenoxy)-1-butenyl)-7-oxabicyclo-[2.2.1]heptan-2-yl]-5-heptenoic acid) showed no effect. PGD(2) or CRTH2 agonist-induced BAL eosinophilia was almost completely inhibited by pretreatment with a CRTH2/TP antagonist, ramatroban [BAY-u3405; (+)-(3R)-3-(4-fluorobenzenesulfonamido)-1,2,3,4-tetra-hydrocarbazole-9-propionic acid], whereas a TP-specific antagonist, SQ29,548 (5-heptenoic, 7-[3-[[2-[(phenylamino)carbonyl]hydrazino]methyl]-7-oxabicyclo[2.2.1]-hept-2-yl]-[1S-[1alpha,2alpha(Z),3alpha,4alpha]]), or a DP-specific antagonist, BW A868C [3-benzyl-5-(6-carboxyhexyl)-1-(2-cyclohexy-2-hydroxyethylamino)-hydantoin], did not inhibit the effects of PGD(2). These results suggest that CRTH2 plays a significant role in the eosinophil trafficking from the bloodstream into the airways in PGD(2)-related airway inflammation.  相似文献   
54.
Major surgical procedures induce a systemic inflammatory response syndrome (SIRS) characterized by the overproduction of proinflammatory cytokines, which induces excessive stress and may trigger postoperative complications. This has prompted the hypothesis that drugs which relieve SIRS might improve the postoperative course of major surgery. One of the most promising targets for these drugs is high-mobility-group box chromosomal protein 1 (HMGB1). In 1999, HMGB1 was found to be a key late mediator of sepsis. It is now known to be associated with various kinds of acute and chronic inflammation, and is recognized as one of the most important danger signals in stress response. In this article, we present the latest information about HMGB1 and discuss its promise as a novel target for modulating stress response.  相似文献   
55.
A 58-year-old female was referred to our hospital with an abnormal shadow on her chest X-ray. Further examination revealed the left anterior descending coronary artery to pulmonary artery fistula with aneurysms. The patient was successfully repaired with operation and had no residual fistulas and aneurysms.  相似文献   
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58.
Extramedullary hematopoiesis predominantly occurs in the liver, spleen, and lymph nodes with hemolytic anemia. Occurrence with osteopetrosis tarda in the paravertebral region is very rare. We discuss the examination of the third known case of paravertebral extramedullary hematopoiesis arising with osteopetrosis tarda.  相似文献   
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60.
BACKGROUND: Recovery of cerebral reperfusion after stroke or cardiac arrest can take a long time. We aimed to identify differences in the postischemic recovery of physiologic parameters between short and prolonged brain ischemia. METHODS: Eighteen Mongolian gerbils were assigned to one of three groups: 5-minute (G5), 15-minute (G15), or 30-minute (G30) ischemia. With the use of our original microspectroscopy system, global ischemic reperfusion was performed. We measured changes in regional cerebral blood flow (r-CBF), microvessel diameter, and brain temperature (BrT) simultaneously. We also monitored somatosensory evoked potentials (SEPs) to evaluate electrophysiologic response. RESULTS: Both G5 and G15 showed concurrent recovery of r-CBF and BrT with hyperemia and hyperthermia, respectively, 10 to 15 minutes after reperfusion. The increase in BrT was <1 degree C and recovered to baseline within 60 minutes after reperfusion. In G30, recovery of r-CBF was significantly delayed relative to that of BrT. The increase in BrT was >2 degrees C, peaking approximately 15 minutes after reperfusion, and then maintained increases of >1 degree C for 120 minutes. SEPs in G5 and G15 showed concomitant recovery with that of r-CBF, whereas SEP recovery in G30 was delayed relative to that of r-CBF, eventually disappearing. All except one of the G30 gerbils died within 24 hours, but all in G5 and G15 survived. CONCLUSIONS: These results suggest that mismatch recovery of r-CBF and BrT after prolonged ischemia initiates metabolic derangement in brain tissue, leading to the electrochemical dysfunction and mortality.  相似文献   
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