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1.
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.  相似文献   
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A dual-color LightCycler PCR assay targeting the 16S rDNA gene of Legionella spp. was established. By using two pairs of hybridization probes, Legionella spp. and Legionella pneumophila could be detected and differentiated simultaneously. With 26 culture-positive and 42 culture-negative respiratory specimens from patients with atypical pneumonia, 100% sensitivity and specificity was observed for L. pneumophila.  相似文献   
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A 77-year-old farmer developed cough with sputum production, fever, bloody nasal discharge and a mass in his right maxillary sinus leading to necrotic ulceration of the sinus. Corynebacterium ulcerans, carrying the beta-phage for the diphtheria toxin and secreting the toxin, was detected microscopically and by culture from the sinusoidal and ulcer discharge. Despite immediate antimicrobial chemotherapy the patient died of pulmonary failure associated with the production of large amounts of very viscous sputum. Identification of the causative agent, pathophysiological aspects and risk factors of this unusal infection are discussed.  相似文献   
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Normal mechanisms of platelet function   总被引:12,自引:0,他引:12  
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Archives of Sexual Behavior - Despite the gaining popularity in mainstream media of the phenomenon that is BDSM, empirical research on the motives and underlying psychological mechanisms driving...  相似文献   
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Montelukast, a cysteinyl leukotriene receptor antagonist, is being developed for the treatment of asthma and related diseases. This study was designed to evaluate whether montelukast at clinically used dosage levels would interfere with the anticoagulant effect of warfarin. In a two-period, double-blind, randomized crossover study, 12 healthy male subjects received a single oral dose of 30 mg warfarin on the 7th day of a 12-day treatment with montelukast, 10 mg daily by mouth, or a placebo. Montelukast had no significant effect on the area under the plasma concentration-time curves and peak plasma concentrations of either R- or S-warfarin. However, slight but statistically significant decreases in time to peak concentration of both warfarin enantiomers and in elimination half-life of the less potent R-warfarin were observed in the presence of montelukast. These changes were not considered as clinically relevant. Montelukast had no significant effect on the anticoagulant effect of warfarin, as assessed by the international normalized ratio (INR) for prothrombin time (AUC0-144 and INR maximum). The results of this study suggest that a clinically important interaction between these drugs is unlikely to occur in patients requiring concomitant administration of both drugs.  相似文献   
8.
A prospective, double-blind, randomized, placebo-controlled study was performed to evaluate the effect of antibiotic prophylaxis in ear surgery. The present study reports on the results of 750 patients, half of whom received cefuroxime for 1 day, the other half, placebo. All postoperative infections occurring within 2 weeks after the intervention were recorded, together with several preoperative and perioperative parameters. It is concluded that exploratory tympanoplasties (including stapedotomy) and “dry perforation” tympanoplasties should be considered “clean” operations according to the American National Research Council and do not benefit from antibiotic prophylaxis. On the other hand, tympanoplasties performed on draining ears and on ears with cholesteatoma should be considered “dirty” operations for which antibiotic prophylaxis may decrease the postoperative infection rate by factor 3. All postoperative infections healed without sequels under proper treatment, except for three that resulted in graft necrosis-one in the placebo group and two in the cefuroxime group. In consequence, prophylaxis may not be mandatory in the dirty group, although the authors advocate its use for the sake of patient and surgeon comfort.  相似文献   
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Background: Autoimmune thyroid disease (AIT) is more common in females than in males. Furthermore, it is well documented that the risk of thyroid autoimmunity increases during pregnancy and in the postpartum period. The objective of the present study was to analyse the association between parity and AIT by using ultrasound and serological data.

Methods: The study population included 2156 women, aged 20–79 years. Serum thyroperoxidase antibodies (anti-TPO) and thyrotropin levels were measured and thyroid ultrasonography was performed. AIT was defined according to the combined presence of a hypoechogenic thyroid pattern and positive anti-TPO levels (>200 IU/ml). Odds ratios (OR) and 95% confidence intervals (CI) were calculated.

Results: The analyses revealed an association between parity and AIT. Women with at least one pregnancy had increased odds for AIT (OR 4.6 [95%-CI 1.4–15.1], p < 0.05) compared to women who have never been pregnant. Similar results were observed using hypoechogenic thyroid pattern (OR 1.7 [95%-CI 1.0–2.9], p < 0.05) and positive anti-TPO levels (OR 1.8 [95%-CI 1.0–3.3], p = 0.05) as separate dependent variables or using number of births as alternate independent variable.

Conclusion: In this female population we found an association between parity and AIT and conclude that parity appears to be a potential risk factor for AIT.  相似文献   
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