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排序方式: 共有6055条查询结果,搜索用时 15 毫秒
81.
Arne Böttcher Thomas Mencke Amelie Zitzmann Rainald Knecht Nathan Jowett Gabriele Nöldge-Schomburg Hans Wilhelm Pau Steffen Dommerich 《European archives of oto-rhino-laryngology》2014,271(2):345-352
Endotracheal intubation has been associated with a threefold higher incidence of laryngopharyngeal complaints following anesthesia in comparison to laryngeal mask airway. Such complaints, including hoarseness and sore throat, have been reported in up to 90 % of patients within 24 h of extubation. The purpose of this study was to determine which preoperatively documented clinical and anatomic parameters are predictive of laryngo-pharyngeal trauma resulting from elective endotracheal intubation. Fifty-three patients undergoing ENT procedures requiring general anesthesia with endotracheal intubation were recruited. Pre and postoperative laryngostroboscopic examination was performed and findings correlated to preoperative clinical and anatomic parameters. Readily assessed anatomic parameters including height (>180 cm) and weight (>80 kg) correlated significantly to the Eckerbom grade of intubation-associated acute laryngeal injury (rs = 0.374; p = 0.006 and rs = 0.278; p = 0.044, respectively). The mandibular protrusion test also correlated significantly to the Eckerbom grade (rs = 0.462, p = 0.001) while the upper-lip-bite test showed significant correlation to impaired vocal fold oscillation (rs = 0.288, p = 0.036), with injury prediction sensitivities of 37.5 and 39.4 %, respectively. No parameters correlated to subjective complaints (n = 5, 9.2 %). This study provides suggestions on how to improve the classification of intubation-associated laryngeal injuries as well as providing the basis for larger clinical trials in other surgical subspecialties. 相似文献
82.
Carsten Nowak Steffen Zuther Sergey V. Leontyev Jutta Geismar 《Conservation Genetics Resources》2014,6(1):159-162
We developed 17 variable microsatellite markers for the threatened Saiga antelope. Using one Illumina Miseq lane resulted in 105,948 unique fragments containing a microsatellite motif. Eighty-one ordered primer pairs resulted in 26 analyzable fragments, of which 17 markers showed variability in at least one population from Kazakhstan. Number of alleles ranged from 2 to 11 and values of heterozygosity varied from 0.08 to 0.91 (HO) and 0.08 to 0.88 (HE). The markers are currently used to delineate conservation units and to help understanding annual migration dynamics in this species. 相似文献
83.
Comparison of metabolic adaptations between endurance‐ and sprint‐trained athletes after an exhaustive exercise in two different calf muscles using a multi‐slice 31P‐MR spectroscopic sequence 下载免费PDF全文
Kevin Moll Alexander Gussew Maria Nisser Steffen Derlien Martin Krämer Jürgen R. Reichenbach 《NMR in biomedicine》2018,31(4)
Measurements of exercise‐induced metabolic changes, such as oxygen consumption, carbon dioxide exhalation or lactate concentration, are important indicators for assessing the current performance level of athletes in training science. With exercise‐limiting metabolic processes occurring in loaded muscles, 31P‐MRS represents a particularly powerful modality to identify and analyze corresponding training‐induced alterations. Against this background, the current study aimed to analyze metabolic adaptations after an exhaustive exercise in two calf muscles (m. soleus – SOL – and m. gastrocnemius medialis – GM) of sprinters and endurance athletes by using localized dynamic 31P‐MRS. In addition, the respiratory parameters VO2 and VCO2, as well as blood lactate concentrations, were monitored simultaneously to assess the effects of local metabolic adjustments in the loaded muscles on global physiological parameters. Besides noting obvious differences between the SOL and the GM muscles, we were also able to identify distinct physiological strategies in dealing with the exhaustive exercise by recruiting two athlete groups with opposing metabolic profiles. Endurance athletes tended to use the aerobic pathway in the metabolism of glucose, whereas sprinters produced a significantly higher peak concentration of lactate. These global findings go along with locally measured differences, especially in the main performer GM, with sprinters revealing a higher degree of acidification at the end of exercise (pH 6.29 ± 0.20 vs. 6.57 ± 0.21). Endurance athletes were able to partially recover their PCr stores during the exhaustive exercise and seemed to distribute their metabolic activity more consistently over both investigated muscles. In contrast, sprinters mainly stressed Type II muscle fibers, which corresponds more to their training orientation preferring the glycolytic energy supply pathway. In conclusion, we were able to analyze the relation between specific local metabolic processes in loaded muscles and typical global adaptation parameters, conventionally used to monitor the training status of athletes, in two cohorts with different sports orientations. 相似文献
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Every dental examination of a child is more than just searching for dental caries. A general anamnesis, assessment of general health and the oral cavity are of great importance. A systematic sequence of examinations helps to avoid mistakes. Knowledge of anatomical structures with the different variations enables healthy structures, morphological variations of the mucosa or even oral lesions as signs of a disease to be differentiated. 相似文献
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89.
Nilsen TO Ebbesson LO Kiilerich P Björnsson BT Madsen SS McCormick SD Stefansson SO 《General and comparative endocrinology》2008,155(3):762-772
The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon. 相似文献
90.
Left ventricular non-compaction: insights from cardiovascular magnetic resonance imaging 总被引:9,自引:0,他引:9
Petersen SE Selvanayagam JB Wiesmann F Robson MD Francis JM Anderson RH Watkins H Neubauer S 《Journal of the American College of Cardiology》2005,46(1):101-105
OBJECTIVES: We aimed to test the diagnostic accuracy of cardiovascular magnetic resonance (CMR) imaging in distinguishing pathological left ventricular non-compaction (LVNC) from lesser degrees of trabecular layering seen in healthy volunteers and, in those with cardiomyopathies and concentric left ventricular hypertrophy, potential differential diagnoses. We hypothesized that pathological trabeculation could be distinguished by determining the ratio of non-compacted to compacted myocardium (NC/C ratio). BACKGROUND: Left ventricular non-compaction is characterized by a non-compacted myocardial layer in the left ventricle. Cardiovascular magnetic resonance images this layer with unprecedented quality, particularly in the ventricular apex, where echocardiography has inherent difficulties. METHODS: We analyzed magnetic resonance cine images, using the 17-segment model in 45 healthy volunteers, 25 athletes, 39 patients with hypertrophic cardiomyopathy and 14 with dilated cardiomyopathy, 17 with hypertensive heart disease, and 30 with aortic stenosis, as well as images from 7 patients previously diagnosed with LVNC whose diagnoses were supported by additional features. RESULTS: Areas of non-compaction were common and occurred more frequently in all groups studied in apical and lateral, rather than in basal or septal, segments. A NC/C ratio of >2.3 in diastole distinguished pathological non-compaction, with values for sensitivity, specificity, and positive and negative predictions of 86%, 99%, 75%, and 99%, respectively. CONCLUSIONS: Left ventricular non-compaction is diagnosed accurately with CMR using the NC/C ratio in diastole. 相似文献