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61.
Recent technological advances in CT imaging have revolutionized non-invasive imaging of the central airways. It is now possible to image the entire central airways in a few seconds and to create elegant three-dimensional reconstructions of the airways in a few minutes. The fast speed of CT scanning now allows for a dynamic assessment of the central airways, expanding the ability to non-invasively detect functional abnormalities such as tracheobronchomalacia. The purpose of this article is to familiarize clinicians with recent advances in airway imaging. A special emphasis is placed upon advanced CT reconstruction methods and their potential contributions to the evaluation of a variety of airway disorders. 相似文献
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Ultrasound guidance for medical thoracoscopy: a novel approach 总被引:2,自引:0,他引:2
Hersh CP Feller-Kopman D Wahidi M Garland R Herth F Ernst A 《Respiration; international review of thoracic diseases》2003,70(3):299-301
BACKGROUND: Commonly, a pneumothorax is induced before medical thoracoscopy to facilitate safe entry into the pleural space. OBJECTIVE: Evaluate the use of transthoracic ultrasound to locate a safe entry site for trocar placement during medical thoracoscopy without induction of a preprocedure pneumothorax. METHOD: The study was designed as a prospective cohort study, performed in the setting of a tertiary care hospital with an active interventional pulmonology program. It included 20 consecutive patients referred for medical thoracoscopy. RESULTS: Ultrasound identified entry sites in all 20 patients. All sites were successfully used, despite the presence of adhesions in 3 patients. There were no complications. CONCLUSIONS: Ultrasound could safely and reliably identify entry sites for trocar placement during medical thoracoscopy, even in patients with pleural adhesions. The use of ultrasound may replace the practice of pneumothorax induction before medical thoracoscopy. 相似文献
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Association between Lp-PLA2 and coronary artery disease: focus on its relationship with lipoproteins and markers of inflammation and hemostasis 总被引:7,自引:0,他引:7
Khuseyinova N Imhof A Rothenbacher D Trischler G Kuelb S Scharnagl H Maerz W Brenner H Koenig W 《Atherosclerosis》2005,182(1):181-188
Lipoprotein-associated phospholipase A2 (Lp-PLA2) generates pro-inflammatory molecules from oxidized LDL. We examined the association between Lp-PLA2 plasma concentrations and risk of stable coronary artery disease (CAD) in a large case-control study and further assessed the relationship between Lp-PLA2 and various lipid, inflammatory and hemostatic parameters. Lp-PLA2 concentrations were measured in 312 patients with CAD and in 479 age- and gender-matched blood donors. Various sensitive inflammatory and hemostatic markers and a complete lipoprotein profile were obtained. Lp-PLA2 concentrations were significantly higher in cases than in controls (296.1 ng/mL versus 266.0 ng/mL, p<0.0001). In multivariable logistic regression, the age- and gender-adjusted OR for the presence of CAD was 1.61 (95% CI, 1.07-2.44) if the top quartile of the Lp-PLA2 distribution was compared to the bottom quartile. Adjustment for traditional cardiovascular risk factors and statin use resulted in an OR of 2.04 (95% CI, 1.19-3.48). After additional controlling for vWF, the OR was slightly attenuated but still remained statistically significant (OR 1.91; 95% CI, 1.12-3.28). Thus, elevated Lp-PLA2 concentrations were associated with the presence of stable CAD, independent of various biochemical markers. Our results support the hypothesis that Lp-PLA2 may be a novel, independent risk marker for CAD. 相似文献
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Stoecklein Veit Michael Kellert Lars Patzig Maximilian Küpper Clemens Giese Armin Ruf Viktoria Weller Jonathan Kreth Friedrich-Wilhelm Schöberl Florian 《Journal of neurology》2021,268(1):367-376
Journal of Neurology - To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous... 相似文献
68.
Caspar Grond-Ginsbach Tiina M. Metso Antti J. Metso Alessandro Pezzini Turgut Tatlisumak Maani Hakimi Armin J. Grau Manja Kloss Christoph Lichy 《Medical hypotheses》2013
Cervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed. 相似文献
69.
Hui Wu Daniel Haag Thomas Muley Arne Warth Marc Zapatka Grischa Toedt Armin Pscherer Meinhard Hahn Ralf J. Rieker David L. Wachter Michael Meister Philipp Schnabel Karin Müller‐Decker Michael A. Rogers Hans Hoffmann Peter Lichter 《Genes, chromosomes & cancer》2013,52(3):250-264
Invasion is a critical step in lung tumor progression. The interaction between tumor cells and their surroundings may play an important role in tumor invasion and metastasis. To better understand the mechanisms of tumor invasion and tumor–microenvironment interactions in lung tumors, total RNA was isolated from the inner tumor, tumor invasion front, adjacent lung, and distant normal lung tissue from 17 patients with primary squamous cell lung carcinoma using punch‐aided laser capture microdissection. Messenger RNA expression profiles were obtained by microarray analysis, and microRNA profiles were generated from eight of these samples using TaqMan Low Density Arrays. Statistical analysis of the expression data showed extensive changes in gene expression in the inner tumor and tumor front compared with the normal lung and adjacent lung tissue. Only a few genes were differentially expressed between tumor front and the inner tumor. Several genes were validated by immunohistochemistry. Evaluation of the microRNA data revealed zonal expression differences in nearly a fourth of the microRNAs analyzed. Validation of selected microRNAs by in situ hybridization demonstrated strong expression of hsa‐miR‐196a in the inner tumor; moderate expression of hsa‐miR‐224 in the inner tumor and tumor front, and strong expression of hsa‐miR‐650 in the adjacent lung tissue. Pathway analysis placed the majority of genes differentially expressed between tumor and nontumor cells in intrinsic processes associated with inflammation and extrinsic processes related to lymphocyte physiology. Genes differentially expressed between the inner tumor and the adjacent lung/normal lung tissue affected pathways of arachidonic acid metabolism and eicosanoid signaling. © 2012 Wiley Periodicals, Inc. 相似文献
70.
Arnt V. Kristen Katrin Ackermann Sebastian Buss Lorenz Lehmann Philipp A. Schnabel Armin Haunstetter Hugo A. Katus Stefan E. Hardt 《Cardiovascular pathology》2013,22(4):280-286
SummaryThe detailed molecular mechanisms following activation of apoptosis in ischemia-reperfusion injury are unknown. This study using different transgenic mouse models provided first evidence that apoptosis in myocardial ischemia-reperfusion injury is rather linked to the mitochondrial pathway than to death receptor pathway.IntroductionThere is a wealth of evidence for activation of apoptosis in ischemia-reperfusion injury. However, the understanding of detailed molecular mechanism is lacking.MethodsThe extent of myocardial infarction after ligation of the left anterior descending artery in mice carrying different transgenes for inhibition of either the intrinsic or the extrinsic or a combination of both apoptotic cascades was evaluated. The extent of myocardial damage was assessed by echocardiographic determination of left ventricular (LV) ejection fraction, LV hemodynamics, troponin T, and histology. The rate of apoptosis was analyzed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and caspase-3 staining.ResultsHighest perioperative rate of death was observed in the dominant-negative form of a truncated Fas-associated death domain (FADD-DN) group. Infarction size by 2,3,5-triphenyltetrazolium chloride (TTC) staining was smaller in the Bcl-2, but not in the other groups as compared to wild-type mice. This was accompanied by lower troponin T values in Bcl-2 transgenic mice as compared to the all other groups. Troponin T correlated well with macroscopic extent of myocardial infarction by TTC staining. A lower decline of LV ejection fraction was seen in the Bcl-2 as compared to wild-type or FADD-DN mice. A smaller number of TUNEL- and caspase-3-positive myocyte nuclei were observed in the Bcl-2 and FADD-DN group as compared to wild-type mice.ConclusionsWe provide first evidence for protective effects on the myocardium in a transgenic mouse model of myocardial ischemia-reperfusion due to inhibition of the Bcl-2, but not the FADD pathway despite that reduced apoptotic cells were observed in both groups as compared to wild-type mice. 相似文献