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991.
Christian Byhahn Dirk Meininger Felix Walcher Christian Hofstetter Bernhard Zwissler 《European journal of emergency medicine》2007,14(1):43-46
Among all prehospital emergency intubations, difficulties occur in 7-10%. Furthermore, intubation conditions often worsen when the cervical spine is immobilized in trauma patients. We report on six patients in whom the Bonfils intubation fiberscope, a reusable, rigid fiberoptic device, was used for emergency endotracheal intubation in the field. Three of these patients had an anticipated or unanticipated difficult airway: two trauma patients with immobilized cervical spine and one patient in cardiac arrest in whom direct laryngoscopy failed twice. Endotracheal intubation with the Bonfils intubation fiberscope was successful in all cases in the first attempt. The Bonfils intubation fiberscope therefore demonstrated its value as an additional airway management device in both emergency and prehospital settings. 相似文献
992.
Kastenmuller W Gasteiger G Gronau JH Baier R Ljapoci R Busch DH Drexler I 《The Journal of experimental medicine》2007,204(9):2187-2198
CD8+ T cell responses directed against multiple pathogen-derived epitopes are characterized by defined immunodominance hierarchy patterns. A possible explanation for this phenomenon is that CD8+ T cells of different specificities compete for access to epitopes on antigen-presenting cells, and that the outcome of this so-called cross-competition reflects the number of induced T cells. In our study using a vaccinia virus infection model, we found that T cell cross-competition is highly relevant during boost vaccination, thereby shaping the immunodominance hierarchy in the recall. We demonstrate that competition was of no importance during priming and was unaffected by the applied route of immunization. It strongly depended on the timing of viral antigen expression in infected APCs, and it was characterized by poor proliferation of T cells recognizing epitopes derived from late viral proteins. To our knowledge, this is the first demonstration of the functional importance of T cell cross-competition during a viral infection. Our findings provide a basis for novel strategies for how boost vaccination to defined antigens can be selectively improved. They give important new insights into the design of more efficient poxviral vectors for immunotherapy. 相似文献
993.
Background
Controlled space closure in cases of isolated lower second premolar aplasia (ILSPA) without maxillary counterbalancing extraction is challenging. Anterior anchorage loss may occur during space closure resulting in compromised occlusal results in terms of an absence of proper canine guidance during laterotrusive mandible movements.In order to evaluate the effectiveness of Herbst telescope anchorage in combination with double-cable, pull mechanics and a completely customized lingual appliance for orthodontic space management in cases of ILSPA, we tested the null hypothesis that there is a significant deterioration in the sagittal canine relationship towards an Angle-Class-II occlusion expressed as a loss of anterior anchorage following space closure with molar mesialization.Methods
Twenty-five consecutively de-bonded subjects (female / male 17 / 8; aged at T0 (start of MB Tx) 12.3 to 20.6 years; mean age 15.0 / SD 1.7 years) were included in this retrospective analysis using the inclusion criteria of least of one lower second premolar aplasia; completed treatment with a totally customized lingual appliance (CCLA) in combination with Herbst telescopes. Exclusion criteria were the absence of counterbalancing maxillary extractions, as well as additional tooth aplasia other than lower second premolars. A total of 33 single, lower premolar aplasia space closures (right / left sided 17 / 16) were assessed using plaster casts and intra-oral photographs scaled to the plaster casts, at bonding (T0), Herbst insertion (T1), following gap closure (T2) and de-bonding (T3). Parallelism of roots was controlled by panoramic x-rays at T3.Results
The mean aplasia space at T0 was 7.5 mm (SD 2.6). Complete space closure was achieved in all 33 situations. The null hypothesis was rejected. There was a significant improvement in the initial canine relationships (mean 3.5 mm distal occlusion at T0) to a mean 0.1 mm at T3. When evaluated against the individual treatment plan, the following amounts of planned improvements were achieved: space closure 100%, canine relationship 97.5%, overjet 93.9%, overbite 96.4%, parallel roots in space closure site 93.9%.Conclusion
Herbst telescope anchorage in combination with double-cable pull mechanics and a CCLA for orthodontic space closure can deliver predictable, high-quality treatment results.994.
Sems Malte Tugtekin Konstantin Alexiou Manuel Wilbring Dirk Daubner Utz Kappert Michael Knaut Klaus Matschke 《Clinical research in cardiology》2006,95(2):72-79
Summary Surgical therapy of native infective endocarditis is still considered as a particular challenge, due to remaining morbidity
and mortality up to 20%. Further risk analysis and characterization of clinical features is of great importance for further
improvement of surgical results. The aim of this retrospective study was a risk analysis concerning clinical features of the
pre–, intra– and postoperative period.
Between 02/1997 and 12/2003, 165 patients (130 male, 35 female, age 55.5 ± 13.8 years) were referred for surgical therapy
of infective endocarditis at our institution. Preoperative, intraoperative and postoperative features were evaluated for their
influence on the early postoperative course and the mid–term follow–up. In the majority of patients (pts) the aortic valve
was infected (n = 83, 50.3% of pts), followed by mitral valve (n = 33; 20.0%), tricuspid valve (n = 10, 6.0%) and pulmonary
valve (n = 2; 1.2%). Double valve affection was recorded in 37 pts (22.4%). Streptococci (n = 66, 40.0%) and staphylococci
(n = 66, 40.0%) were the most common pathogens. The overall hospital mortality rate was 10.9% (n = 18), during follow–up (mean
follow–up 3.3 ± 2.5 years) a further 20 pts (12.1%) died.
Main predictors for hospital mortality in multivariate analysis were older age (p = 0.01), prolonged ICU stay, prolonged intubation
(p = 0.03; p = 0.02) and the continuous postoperative need of alpha–catecholamine medication (p < 0.01). Significant predictors
of overall mortality were older age (> 70 years) and diabetes (p = 0.03; p = 0.03). Reinfection occurred in 6.1% of patients
(n = 10). Actuarial freedom from recurrent infection was 97% at 1 year and 93.9% at 5 years. Surgical therapy of infective
endocarditis is associated with good clinical results in the early and mid–term follow–up. Predictors of outcome particular
include preoperative risk constellation or comorbidity (age, diabetes) and variables of the immediate postoperative course. 相似文献
995.
Wade G. Alleman MD Brian Gorman MB BCh Bernard F. King MD Dirk R. Larson MS John C. Cheville MD Ajay Nehra MD 《Journal of ultrasound in medicine》2008,27(8):1195-1202
Objective. The purpose of this study was to determine whether the clinical history and sonographic appearance of solid epididymal masses could aid in distinguishing benign and malignant disease. Methods. We retrospectively reviewed the medical records of all patients who had solid epididymal masses evaluated by scrotal sonography at our institution between 1996 and 2004. We evaluated multiple clinical and sonographic variables, including lesion size, location, echogenicity, color Doppler characteristics, and calcifications. Results. Of the 85 patients included in the study, 25 (29%) underwent surgical intervention, and 5 (6%) had malignant disease. A mass size of greater than 1.5 cm and the presence of color Doppler flow were statistically significant markers for malignancy (P < .05). Combining these 2 variables as a test for malignancy yielded sensitivity of 100%, specificity of 80%, a positive predictive value of 24%, and a negative predictive value of 100%. Conclusions. Most solid epididymal masses (94%) are benign. A size of greater than 1.5 cm and the presence of color Doppler flow may help identify possible malignant masses. 相似文献
996.
Monomethoxy poly(ethylene glycol)-block-poly(trimethylene carbonate) (mPEG(3)-PTMC(11), M(n) of mPEG=3.1 x 10(3) and M(n) of PTMC=10.8 x 10(3)g/mol) was synthesized by ring-opening polymerization of TMC using mPEG(3) as an initiator and stannous octoate as a catalyst. The block copolymer has a broad melting range with a peak at 49.5 degrees C and a heat of fusion of 47.6J/g. The heat of fusion normalized to the mPEG content is higher than that of the mPEG(3) polymer, suggesting that PTMC segments are also semi-crystalline. The mPEG(3)-PTMC(11) films were stable in water at room temperature, whereas at 37 degrees C the film specimens disintegrated and the amphiphilic block copolymer self-assembled into micellar-like nanoparticles with average sizes up to 210nm. The critical association concentration (CAC) of the formed micellar-like particles is 1.35 x 10(-3)mg/ml. The average size and polydispersity index of the formed mPEG(3)-PTMC(11) nanoparticles depend on temperature and storage time: the values decrease with increases in temperature and in storage time. By co-dissolving dexamethasone with mPEG(3)-PTMC(11) during the film preparation, micellar-like nanoparticles loaded with dexamethasone can be obtained after the film to micellar-like nanoparticles transition. A high loading efficiency of 93.3 wt.% was achieved. The sustained release of the drug was complete in 20d. 相似文献
997.
Johanna Gutleben Maryam Chaib De Mares Jan Dirk van Elsas Hauke Smidt Jörg Overmann 《Critical reviews in microbiology》2018,44(2):212-229
The numbers and diversity of microbes in ecosystems within and around us is unmatched, yet most of these microorganisms remain recalcitrant to in vitro cultivation. Various high-throughput molecular techniques, collectively termed multi-omics, provide insights into the genomic structure and metabolic potential as well as activity of complex microbial communities. Nonetheless, pure or defined cultures are needed to (1) decipher microbial physiology and thus test multi-omics-based ecological hypotheses, (2) curate and improve database annotations and (3) realize novel applications in biotechnology. Cultivation thus provides context. In turn, we here argue that multi-omics information awaits integration into the development of novel cultivation strategies. This can build the foundation for a new era of omics information-guided microbial cultivation technology and reduce the inherent trial-and-error search space. This review discusses how information that can be extracted from multi-omics data can be applied for the cultivation of hitherto uncultured microorganisms. Furthermore, we summarize groundbreaking studies that successfully translated information derived from multi-omics into specific media formulations, screening techniques and selective enrichments in order to obtain novel targeted microbial isolates. By integrating these examples, we conclude with a proposed workflow to facilitate future omics-aided cultivation strategies that are inspired by the microbial complexity of the environment. 相似文献
998.
Gründemann D Hahne C Berkels R Schömig E 《The Journal of pharmacology and experimental therapeutics》2003,304(2):810-817
Agmatine has received considerable attention recently. Available evidence suggests that agmatine functions as a neurotransmitter and inhibits, via induction of antizyme, cellular proliferation. Because of its positive charge, agmatine will not appreciably cross cellular membranes by simple diffusion. Indeed, all physiological models require a channel or transporter protein in the plasma membrane to effect inactivation or nonexocytotic release of agmatine. However, a transport mechanism for agmatine has not been identified on a molecular level so far. In the present study, the non-neuronal monoamine transporters, organic cation transporter (OCT) 1, OCT2, and extraneuronal monoamine transporter (EMT) (gene symbols SLC22A1-A3), both from human and rat, were examined, stably expressed in 293 cells, for [(3)H]agmatine transport. Our results indicate that OCT2 and EMT, but not OCT1, efficiently translocate agmatine. The structural homolog putrescine was not accepted as substrate. Uptake of agmatine via EMT and OCT2 was saturable, with K(m) values of 1 to 2 mM. The affinity of OCT1 was 10-fold lower. Carrier-mediated efflux of agmatine was documented in a trans-stimulation experiment. Finally, uptake of agmatine increased dramatically with increasing pH. Thus, only the singly charged species of agmatine is accepted as substrate. In conclusion, both EMT and OCT2 must be considered for the control of agmatine levels in rat and human. 相似文献
999.
Comparison of signal quality between EASI and Mason-Likar 12-lead electrocardiograms during physical activity. 总被引:2,自引:0,他引:2
Annika Welinder Leif S?rnmo Dirk Q Feild Charles L Feldman Jonas Pettersson Galen S Wagner Olle Pahlm 《American journal of critical care》2004,13(3):228-234
BACKGROUND: Myoelectric noise and baseline wander, artifacts that appear when patients move during electrocardiographic monitoring, can cause false alarms. This problem can be addressed by using a reduced lead set and placing electrodes on the anterior part of the torso only. The Mason-Likar modification of the standard 12-lead electrocardiogram and the EASI lead system are 2 alternative systems for lead placement. OBJECTIVES: To test the hypothesis that the EASI lead system is less susceptible to artifacts than is the Mason-Likar modification of the standard 12-lead electrocardiogram. METHODS: Baseline wander and myoelectric noise amplitudes of EASI and Mason-Likar 12-lead electrocardiograms were compared. Twenty healthy volunteers participated. Both lead systems were recorded simultaneously for different types of physical activities. For each lead in each subject, baseline wander and myoelectric noise were measured for both systems, at rest and during each physical activity. RESULTS: The outcome for baseline wander was mixed. For myoelectric noise content, the EASI system performed better for the limb leads in the different physical activities. In the precordial leads, the differences were minimal or mixed. However, for supine-to-right turning, EASI performed worse than the Mason-Likar system. CONCLUSIONS: The 2 systems have similar susceptibilities to baseline wander. The EASI system is, however, less susceptible to myoelectric noise than is the Mason-Likar system. EASI performed worse than Mason-Likar for turning supine to right, because only the EASI system uses an electrode in the right-midaxillary line. 相似文献
1000.
Impaired chemoreflex sensitivity in adult patients with multiple organ dysfunction syndrome—the potential role of disease severity 总被引:2,自引:1,他引:2
Schmidt H Müller-Werdan U Nuding S Hoffmann T Francis DP Hoyer D Rauchhaus M Werdan K 《Intensive care medicine》2004,30(4):665-672
Objective The cardiac chemoreflex sensitivity is a powerful predictor of autonomic dysfunction in chronic heart failure and after myocardial infarction. The objective of the present study was to characterize cardiac chemoreflex sensitivity in patients with multiple organ dysfunction syndrome (MODS). We also aimed to elucidate the effect of the severity of MODS on the assessment of cardiac chemoreflex sensitivity.Design Prospective cohort study.Setting Twelve-bed medical intensive care unit in a university center.Patients Forty consecutively admitted patients with MODS during a 7-month period. Patients with MODS were identified by an APACHE II score of 20 or more. Sepsis was defined as a Sepsis Score, according to Elebute and Stoner, of 12 or more.Interventions The cardiac chemoreflex sensitivity was assessed using the regression of heart interval (ms) versus arterial oxygen pressure (mmHg).Measurements and results First, we established a new method to assess cardiac chemoreflex sensitivity and applied it to healthy controls and patients. Second, we found that cardiac chemoreflex sensitivity correlated with the severity of MODS as calculated by the APACHE II score (r2=0.34, p=0.001). This relation was best fitted by a model including minimum heart rate and standard bicarbonate in 24 h (r2=0.5, p<0.001) and Glasgow Coma Scale (r2=0.5, p=0.005). Age, however, did not significantly contribute (r2=0.001, p=0.8).Conclusions The calculation of cardiac chemoreflex sensitivity enabled us to quantify an important component of the cardiorespiratory interactions in patients with MODS. Severity of illness was a more pronounced determinant of impaired cardiac chemoreflex sensitivity than age. The quantification of the cardiorespiratory interactions by measuring the cardiac chemoreflex sensitivity has potential to identify a subgroup of patients with worse prognosis. 相似文献