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Ventilator-associated pneumonia (VAP) is the most common intensive care unit (ICU)-acquired infection among patients requiring mechanical ventilation. A prospective surveillance programme of all patients has been implemented at the ICU, Karolinska University Hospital, Sweden since 2001. Within this programme, incidence and risk factors for ICU-acquired pneumonia and associated death over a 2-y period have been studied. Of 329 patients enrolled in the study, 221 required mechanical ventilation. 33 of 221 patients (15%) developed VAP, corresponding to a rate of 29 VAP/1000 ventilator d. Risk factors for VAP were aspiration (hazard ratio 3.79; 95% CI 1.48-9.68), recent surgery (HR 3.58; 95% CI 1.15-11.10) and trauma (HR 3.00; 95% CI 1.03-8.71). 11 patients of 33 (33%) with VAP died within 28 d compared to 46 of 288 (16%) without ICU-acquired pneumonia (odds ratio 2.73; 95% CI 0.97-7.63). We conclude that: 1) incidence of VAP was 15% and the most important risk factor was aspiration; 2) APACHE II score > or = 20 is a stronger predictor for poor outcome than VAP; 3) a minority of patients with APACHE II score > or = 20 develop VAP; and 4) continuous surveillance programmes are feasible and provide valuable data for improvement of quality of care.  相似文献   
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A large foodborne outbreak caused by Norwalk-like virus (NLV) among children and staff at 30 day care centers provided an opportunity to study symptomatology and attack rates among patients in different age groups, as well as secondary transmission rates in centers and households. A retrospective cohort study of 775 subjects from 13 randomly chosen centers was performed. Diarrhea was more common in adults than in children (P=.001), whereas the reverse was noted with regard to vomiting (P=.003). The primary attack rate was 27% (142 of 524 subjects): 54% of adults versus 19% of children (P<.001). The mean incubation time for foodborne cases of infection was 34 hours. The secondary attack rate was 17%. Risk factors for spread into households were the primary case being a child (relative risk [RR], 3.8; 95% confidence interval [CI], 1.9-7.6) and vomiting (RR, 2.4; 95% CI, 1.0-5.5). The incubation time for person-to-person transmission was approximated by a mean serial interval of 52 hours. This is the first reported outbreak of NLV infection in which secondary transmission into households by individuals has been studied.  相似文献   
34.
Dommisch  H.  Stolte  KN.  Jager  J.  Vogel  K.  Müller  R.  Hedtrich  S.  Unbehauen  M.  Haag  R.  Danker  K. 《Clinical oral investigations》2021,25(10):5795-5805
Objectives

Topical drug administration is commonly applied to control oral inflammation. However, it requires sufficient drug adherence and a high degree of bioavailability. Here, we tested the hypothesis whether an ester-based core-multishell (CMS) nanocarrier is a suitable nontoxic drug-delivery system that penetrates efficiently to oral mucosal tissues, and thereby, increase the bioavailability of topically applied drugs.

Material and methods

To evaluate adhesion and penetration, the fluorescence-labeled CMS 10-E-15-350 nanocarrier was applied to ex vivo porcine masticatory and lining mucosa in a Franz cell diffusion assay and to an in vitro 3D model. In gingival epithelial cells, potential cytotoxicity and proliferative effects of the nanocarrier were determined by MTT and sulphorhodamine B assays, respectively. Transepithelial electrical resistance (TEER) was measured in presence and absence of CMS 10-E-15-350 using an Endohm-12 chamber and a volt-ohm-meter. Cellular nanocarrier uptake was analyzed by laser scanning microscopy. Inflammatory responses were determined by monitoring pro-inflammatory cytokines using real-time PCR and ELISA.

Results

CMS nanocarrier adhered to mucosal tissues within 5 min in an in vitro model and in ex vivo porcine tissues. The CMS nanocarrier exhibited no cytotoxic effects and induced no inflammatory responses. Furthermore, the physical barrier expressed by the TEER remained unaffected by the nanocarrier.

Conclusions

CMS 10-E-15-350 adhered to the oral mucosa and adhesion increased over time which is a prerequisite for an efficient drug release. Since TEER is unaffected, CMS nanocarrier may enter the oral mucosa transcellularly.

Clinical relevance

Nanocarrier technology is a novel and innovative approach for efficient topical drug delivery at the oral mucosa.

  相似文献   
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36.
食管癌的诊断和治疗   总被引:4,自引:8,他引:4  
1诊断 1.1普查由于食管早期癌的疗效明显好于进展期癌,加之,内镜下食管粘膜切除术用于无淋巴结转移的表浅食管癌的根治已取得良好疗效,并已逐渐被医患双方所接受,因而普查仍是目前改善食管癌(EC)疗效的肯定手段.我国北方尤其是太行山地区及伊朗里海沿岸居民、有头颈癌肿史者是EC的高发人群.  相似文献   
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Background and Objectives Keeping a small stock of liquid plasma readily available for transfusion is common practise in Sweden. We report data on complement activation markers in plasma components during storage in the liquid state and the kinetics of C3a‐desArg after transfusion of autologous plasma with high content of C3a‐desArg. Material and Methods Plasma components were prepared by apheresis or from whole blood. C3 fragments (C3a‐desArg, C3d,g, iC3), and soluble terminal complement complex (sC5b‐9) were investigated. C3a‐desArg kinetics was investigated in regular apheresis donors. Results Apheresis plasma prepared by membrane centrifugation had significantly higher level of C3a‐desArg, C3d,g and sC5b‐9 from day 0 and low iC3, than plasma prepared by other methods. By storage day 7, C3a‐desArg ‐levels were above the reference value in 88% of all components. After re‐infusion of autologous plasma with high C3a‐desArg content, there were rapid a1 and a2‐distribution followed by a slower b‐elimination phase. Conclusion Plasma components prepared by different methods and stored in the liquid phase differ significantly in the amount and timing of complement activation. C3a‐desArg present in plasma is rapidly eliminated after transfusion. Autologous plasma could be used to study complement kinetics in different clinical situations.  相似文献   
39.
Previous research has suggested that a short-term (6 week) high-intensity and a subsequent long-term (1 year) low-intensity dynamic training programme in 8 patients with rheumatoid arthritis (RA) increased circulating levels of beta-endorphin (beta-EP) during the high-intensity training and of corticotropin-releasing factor (CRF) and beta-lipotropin (beta-LPH) levels during the low-intensity training, without an increase of pain experience. The present follow-up study of the patients, using the data obtained after an additional 1-year period of no standardized training as reference values, indicated that CRF levels decreased significantly (P less than 0.01) in relation to those obtained 1 year earlier. For beta-LPH and beta-EP, no corresponding decreases were noted. No significant difference concerning experience of pain over time was found. High-performance liquid chromatography demonstrated a complex elution pattern with low basal concentration of beta-LPH, which increased after 60 min of training.  相似文献   
40.
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