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排序方式: 共有2668条查询结果,搜索用时 15 毫秒
91.
Marianne R. Spalinger Stephanie Kasper Claudia Gottier Silvia Lang Kirstin Atrott Stephan R. Vavricka Sylvie Scharl Tina Raselli Isabelle Frey-Wagner Petrus M. Gutte Markus G. Grütter Hans-Dietmar Beer Emmanuel Contassot Andrew C. Chan Xuezhi Dai David J. Rawlings Florian Mair Burkhard Becher Werner Falk Michael Fried Gerhard Rogler Michael Scharl 《The Journal of clinical investigation》2016,126(11):4388
92.
Jutta Pikalo Tessa Carrau Paul Deutschmann Melina Fischer Kore Schlottau Martin Beer Sandra Blome 《Viruses》2022,14(2)
African swine fever (ASF) is a major threat to pig production, and real-time PCR (qPCR) protocols are an integral part of ASF laboratory diagnosis. With the pandemic spread of ASF, commercial kits have risen on the market. In Germany, the kits have to go through an approval process and thus, general validation can be assumed. However, they have never been compared to each other. In this study, 12 commercial PCR kits were compared to an OIE-recommended method. Samples representing different matrices, genome loads, and genotypes were included in a panel that was tested under diagnostic conditions. The comparison included user-friendliness, internal controls, and the time required. All qPCRs were able to detect ASFV genome in different matrices across all genotypes and disease courses. With one exception, there were no significant differences when comparing the overall mean. The overall specificity was 100% (95% CI 87.66–100), and the sensitivity was between 95% and 100% (95% CI 91.11–100). As can be expected, variability concerned samples with low genome load. To conclude, all tests were fit for purpose. The test system can therefore be chosen based on compatibility and prioritization of the internal control system. 相似文献
93.
Link TM Vieth V Stehling C Lotter A Beer A Newitt D Majumdar S 《European radiology》2003,13(4):663-671
The purpose of this study was to compare trabecular bone structure parameters obtained from high-resolution magnetic resonance
(HRMR) and multislice computed tomography (MSCT) images with those determined in contact radiographs from corresponding specimen
sections. High-resolution MR and MSCT images were obtained in 39 distal radius specimens. For HRMR the in-plane spatial resolution
was 0.152×0.153 mm2 with a slice thickness of 0.9 and 0.3 mm using a 3D T1-weighted spin-echo sequence. For MSCT the resolution was 0.247×0.247 mm2 with a collimation of 1 mm. Using a diamond saw, 117 0.9- to 1-mm-thick sections were obtained from these specimens and contact
radiographs were acquired. In the corresponding sections structure parameters analogous to bone histomorphometry were determined.
Significant correlations between MR- and CT-derived structure parameters and those derived from the contact radiographs were
found (p<0.01); r values of up to 0.75 were obtained for HRMR imaging and up to 0.70 for MSCT. On the average, structure parameters
showed higher correlations for the MR- than for the CT-derived data. For the MR data the threshold algorithm used for binarizing
the images substantially affected these correlations. In conclusion, trabecular bone structure parameters assessed in distal
radius HRMR and MSCT images are significantly correlated with those determined in corresponding specimen sections (p<0.01). High-resolution MR-derived structure parameters, however, performed better in the prediction of trabecular bone structure.
Electronic Publication 相似文献
94.
95.
Ambros J Beer Roland Haubner Ingo Wolf Michael Goebel Stephan Luderschmidt Markus Niemeyer Anca-Ligia Grosu Maria-Jose Martinez Hans Jürgen Wester Wolfgang A Weber Markus Schwaiger 《Journal of nuclear medicine》2006,47(5):763-769
(18)F-Galacto-RGD is a new tracer for PET imaging of alpha v beta3, a receptor involved in a variety of pathologic processes including angiogenesis and metastasis. Our aim was to study the dosimetry of (18)F-galacto-RGD in humans. METHODS: Eighteen patients with various tumors (musculoskeletal tumors [n = 10], melanoma [n = 5], breast cancer [n = 2], or head and neck cancer [n = 1]) were examined. After injection of 133-200 MBq of (18)F-galacto-RGD, 3 consecutive emission scans from the thorax to the pelvis were acquired at 6.7 +/- 2.9, 35.6 +/- 7.6, and 70.4 +/- 12.2 min after injection. Blood samples (n = 4) for metabolite analysis were taken 10, 30, and 120 min after injection. The OLINDA 1.0 program was used to estimate the absorbed radiation dose. RESULTS: Reversed-phase high-performance liquid chromatography of serum revealed that more than 95% of tracer was intact up to 120 min after injection. (18)F-Galacto-RGD showed rapid clearance from the blood pool and primarily renal excretion. Background activity in lung and muscle tissue was low (percentage injected dose per liter at 71 min after injection, 0.56 +/- 0.15 and 0.69 +/- 0.25, respectively). The calculated effective dose was 18.7 +/- 2.4 microSv/MBq, and the highest absorbed radiation dose was in the bladder wall (0.22 +/- 0.03 mGy/MBq). CONCLUSION: (18)F-Galacto-RGD demonstrates high metabolic stability, a favorable biodistribution, and a low radiation dose. Consequently, this tracer can safely be used for noninvasive imaging of molecular processes involving the alpha v beta3 integrin and for the planning and monitoring of therapeutic approaches targeting alpha v beta3. 相似文献
96.
Regression of left atrial diameter after kidney transplantation is associated with prolonged survival: an observational study 下载免费PDF全文
Michael Kammer Arno Beer Regina Steringer‐Mascherbauer Thomas Binder Rainer Oberbauer 《Transplant international》2018,31(9):999-1007
Renal transplantation reduces the dramatically elevated risk of cardiovascular death in dialysis patients. We previously showed that left atrial diameter before transplantation predicts cardiovascular and overall mortality. Now, we investigated the association of changes in cardiac morphology after transplantation and mortality. We retrospectively analyzed data from the Austrian transplant repository using multivariable Cox and competing risk models and multivariable logistic regression for the prediction of changes in cardiac morphology. We identified 414 patients with a median follow‐up of 8 years and observed a significant progression of mean diameter of left atrium (LA), right atrium and right ventricle and a significant regression of left ventricle. Complete case analysis of 243 patients with a regression of initially enlarged LA diameter had a significantly lower risk of adjusted overall and cardiovascular mortality; hazard ratio (HR 0.45, 95% CI 0.30–0.69, P < 0.001, 124 deaths), and HR of 0.43 [95% CI 0.21–0.92, P = 0.029, 48 cardiovascular (CV) deaths], respectively. Only age at transplantation was significantly associated with regression of LA (OR 0.75, 95% CI 0.60–0.93, P = 0.007). Patients with regression of LA after kidney transplantation exhibited a lower overall and CV mortality risk. Besides age, peritoneal dialysis and antihypertensive therapy were mediators of LA regression. 相似文献
97.
T. W. Beer 《Journal of clinical pathology》1992,45(4):353-355
Two cases of solitary rectal ganglioneuromas are reported, one in a patient with several previously resected colorectal adenomas, the other in a patient with no known predisposing pathology. No prior reports of cases of solitary rectal ganglioneuroma have been published as far as is known, and the origin of similar lesions which have been reported at other sites in the gastrointestinal tract is a subject for speculation. 相似文献
98.
Prevalence and impact of metabolic syndrome on hospital outcomes in acute myocardial infarction 总被引:11,自引:0,他引:11
Zeller M Steg PG Ravisy J Laurent Y Janin-Manificat L L'Huillier I Beer JC Oudot A Rioufol G Makki H Farnier M Rochette L Vergès B Cottin Y;Observatoire des Infarctus de Côte-d'Or Survey Working Group 《Archives of internal medicine》2005,165(10):1192-1198
BACKGROUND: The impact of metabolic syndrome after acute myocardial infarction (AMI) has not yet been studied. In a population-based sample of patients with AMI, we sought to determine the prevalence of metabolic syndrome in patients with AMI, its impact on hospital outcomes, and to assess the relative influence of each of the components of the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III definition of metabolic syndrome on the risk of death and heart failure. METHODS: A total of 633 unselected, consecutive patients hospitalized with AMI were categorized according to the NCEP ATP III metabolic syndrome criteria (presence of >/=3 of the following: hyperglycemia; triglyceride level >/=150 mg/dL [>/=1.7 mmol/L]; high-density lipoprotein cholesterol level <40 mg/dL [<1.04 mmol/L] in men and <50 mg/dL [<1.30 mmol/L] in women; blood pressure >/=130/85 mm Hg; and waist circumference >102 cm in men or 88 cm in women). RESULTS: Among the 633 patients, 290 (46%) fulfilled the criteria for metabolic syndrome. Patients with metabolic syndrome were older and more likely to be women. Acute myocardial infarction characteristics and left ventricular ejection fraction rates were similar for both groups. In-hospital case fatality was higher in patients with metabolic syndrome compared with those without, as was the incidence of severe heart failure (Killip class >II). In multivariate analysis, metabolic syndrome was a strong and independent predictor of severe heart failure, but not in-hospital death. Analysis of the predictive value of each of the 5 metabolic syndrome components for severe heart failure showed that hyperglycemia was the major determinant (odds ratio, 3.31; 95% confidence interval, 1.86-5.87). CONCLUSIONS: In an unselected population of patients with AMI, the prevalence of metabolic syndrome was high. Metabolic syndrome appeared associated with worse in-hospital outcome, with a higher risk of development of severe heart failure. Among metabolic syndrome components, hyperglycemia was the main correlate of the risk of development of severe heart failure during AMI. 相似文献
99.
Platelet-derived growth factor (PDGF) is a potent mitogen for many cultured connective tissue cells. It is present in concentrated form within the platelet alpha-granules and is believed to be released during platelet degranulation at sites of vascular injury. We have used a sensitive radioreceptor assay to measure PDGF levels in whole blood serum from normal humans [17.5 +/- 3.1 (SD) ng/mL] and baboons (2.7 +/- 1.2 ng/mL). PDGF was not detected in plasma from either species. In addition, plasma was found to substantially reduce the ability of added purified PDGF to bind to the cell surface PDGF receptor on cultured cells, suggesting that plasma may contain a PDGF-binding protein that would serve to inactivate PDGF released into plasma. Calculations of PDGF concentrations in serum have been corrected for the effects of the binding protein. 125I-PDGF injected intravenously into normal baboons was cleared rapidly from the plasma (t1/2 = two minutes). The rapid clearance of 125I-PDGF did not result from iodination damage, as purified unlabeled PDGF was cleared with comparable kinetics. The rapid clearance of purified and iodinated PDGF did not result from changes in PDGF structure during purification or from removal of PDGF-associated proteins during purification, as PDGF present in freeze-thaw lysates of fresh platelets was cleared equally rapidly. We conclude that release of PDGF at sites of vascular injury would greatly increase the local concentration of PDGF and that PDGF not localized to the site of injury would be rapidly cleared from the circulation. 相似文献
100.
Lymphocyte recruitment to the lung 总被引:11,自引:0,他引:11
J S Berman D J Beer A C Theodore H Kornfeld J Bernardo D M Center 《The American review of respiratory disease》1990,142(1):238-257
Lymphocyte recruitment in lymphoid tissues and inflammatory sites occurs in response to two events. The first is adherence of lymphocytes to specialized molecules expressed on the surface of appropriately stimulated vascular endothelial cells known as vascular addressins. The interaction occurs via specialized lymphocyte surface molecules known as homing receptors. There is considerable diversity among these molecules. At least three, and possibly four, different addressin-homing receptor pairs exist, regulating entry into peripheral lymph nodes, gut lymphoid tissue, BALT and intrathoracic lymphoid tissue, and inflamed synovium. Vascular addressins are expressed by specialized endothelial cells known as HEV. HEV are not found in normal lung parenchyma but may be induced to appear during an immune response. The mechanism for induction of HEV is unknown, although it may involve the action of inflammatory cytokines. It is not known whether separate endothelial cells exist with a propensity to develop into HEV or if any endothelial cells will develop into HEV if stimulated in the proper manner. Other accessory, lymphocyte-endothelium adhesion molecule pairs have been described, including LFA-1-ICAM-1 and CD4-HLA-DR. These molecules are induced by exposure of the endothelium to inflammatory cytokines, chiefly IFN-gamma. Thus, local humoral influences present during inflammation can alter the possibility of lymphocyte traffic through the endothelium by regulating the presence of lymphocyte adherence molecules. These processes have been documented to occur in the lung in normal homeostasis (e.g., BALT) and in disease (e.g., immunization with SRBC). After adherence, lymphocytes exit the circulation via amoeboid motility. This motility can be altered and enhanced through chemoattractant substances that act via surface receptors. The biochemical basis of cell motility is not entirely clear but appears to involve a link between the second messengers of receptor signaling and changes in the cytoskeleton, particularly actin filaments and microtubules. Like fibroblasts and smooth muscle cells, lymphocytes appear to respond to a number of "mitoattractants," substances that cause cell cycle entry and/or progression as well as enhanced motility. This relationship illustrates the integral relationship between cell motility and proliferation and suggests that the process of cell recruitment might also prime the recruitment cells to become activated to proliferate and perform effector function. Studies of lymphocyte-mediated lung disease confirm that antigen-specific as well as antigen-nonspecific lymphocytes are selectively recruited to the lung from the circulation during an inflammatory reaction in the lung.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献