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171.
A receptor guanylyl cyclase expressed specifically in olfactory sensory neurons. 总被引:6,自引:1,他引:6 下载免费PDF全文
H J Fülle R Vassar D C Foster R B Yang R Axel D L Garbers 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(8):3571-3575
We have cloned an additional member (GC-D) of the membrane receptor guanylyl cyclase [GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2] family that is specifically expressed in a subpopulation of olfactory sensory neurons. The extracellular, putative ligand-binding domain of the olfactory cyclase is similar in primary structure to two guanylyl cyclases expressed in the retina but diverges considerably from other known guanylyl cyclases. The expression of GC-D RNA is restricted to a small, randomly dispersed population of neurons that is within a single topographic zone in the olfactory neuroepithelium and resembles the pattern of the more diverse seven-transmembrane-domain odorant receptors. These observations suggest that GC-D may function directly in odor recognition or in modulating the sensitivity of a subpopulation of sensory neurons to specific odors. 相似文献
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Julia Anna Lurz Christian Luecke David Lang Christian Besler Karl-Philipp Rommel Karin Klingel Reinhard Kandolf Volker Adams Katharina Schöne Gerhard Hindricks Gerhard Schuler Axel Linke Holger Thiele Matthias Gutberlet Philipp Lurz 《JACC: Cardiovascular Imaging》2018,11(1):38-45
Objectives
The aim of the present study was to evaluate whether extracellular volume fraction (ECV) can reliably inform on the extent of diffuse fibrosis in the simultaneous presence of myocardial inflammation, which has not been verified to date.Background
Diffuse myocardial fibrosis is associated with unfavorable outcome in patients with cardiomyopathy, and is of prognostic relevance. Assessment of ECV bears promise for being a noninvasive surrogate parameter, but it may be altered by other pathologies.Methods
In this prospective study, 107 consecutive patients with clinical suspicion of inflammatory cardiomyopathy were included. All patients underwent left ventricular (LV) endomyocardial biopsy (EMB) and cardiac magnetic resonance imaging on a 1.5-T scanner. T1 mapping was obtained with the modified Look-Locker inversion recovery sequence, and ECV was calculated.Results
Myocardial inflammation was present in 66 patients. Patients with and without inflammation were of similar age and had comparable LV ejection fraction (37 ± 17% vs. 36 ± 18%; p = 0.9) and symptom duration (median 14 days [interquartile range: 5 to 36 days] vs. median 14 days [interquartile range: 7 to 30 days]; p = 0.73). Although LV collagen volume percentage was comparable between groups (inflammation 12.3 ± 17.8% vs. noninflammation 11.4 ± 7.9%; p = 0.577), ECV was significantly higher in patients with inflammation (0.37 ± 0.06%) than in those without inflammation (0.33 ± 0.08%; p = 0.02). Importantly, ECV adequately estimated the degree of LV fibrosis percentage only in patients without inflammation (r = 0.72; p < 0.0001) and not in those with inflammation (r = 0.24; p = 0.06).Conclusions
These findings prove the theoretical concept of ECV as an estimate for diffuse myocardial fibrosis, but only in the absence of significant myocardial inflammation. Assuming that various degrees of myocardial inflammation and fibrosis coexist in such a scenario, the measured ECV will reflect a sum of these different pathologies but will not inform solely on the extent of diffuse fibrosis. 相似文献176.
Axel Gossmann Hans Theodor Eich reas Engert reas Josting Rolf-Peter Müller Volker Diehl Klaus-Jürgen Lackner 《European journal of haematology》2005,75(S66):83-89
Abstract: Initial staging of Hodgkin's disease is crucial to determine the location and extent of disease, and is the hallmark for the choice of treatment. At present, the established radiological technique for staging Hodgkin's disease is computed tomography (CT). Modern multidetector row CT scanners allow fast imaging from the scull base to the groins during a single breath hold with a spatial resolution of approximately 1 mm. Both, nodal and extranodal involvement of Hodgkin's disease can be diagnosed with CT. Magnetic resonance (MR) imaging is another useful cross-sectional imaging modality for staging Hodgkin's disease. The development of fast MR imaging techniques has considerably reduced imaging time without compromising the quality of MR images. As a consequence, MR imaging is now considered to be as diagnostic as CT for staging Hodgkin's disease. The excellent soft-tissue contrast and the lack of exposure to ionizing radiation are the main advantages of MR imaging. For the detection of extranodal Hodgkin's disease, MR imaging is superior to assess involvement of the brain, the spinal cord and bone marrow; while CT allows excellent evaluation of lung disease. Common major problems in staging Hodgkin's disease are still the detection of nodal involvement in normal sized lymph nodes and residual tumor masses after therapy. In the future, newly developed lymphotropic contrast agents for MR imaging might be helpful to answer these questions. 相似文献
177.
Sonja Vestergaard Karen Andersen-Ranberg Axel Skytthe Kaare Christensen Bernard Jeune 《European journal of ageing》2016,13(1):15-23
Using the results from measures of functional ability, cognitive and physical performance from two adjacent birth cohorts of 100-year-old adults, we aimed to elucidate the possible impact of difference in participation rates, design, and interviewer mode. Participants were birth cohort members born in 1910 (DK-1910) and 1911-12 (DK-1911). Both surveys used the same assessment instruments, but the design was different, and data collection was carried out by trained survey agency interviewers in DK-1910 and trained nurses in DK-1911. Participation rate in DK-1911 (49.8 % (251/504)) was lower than in DK-1910 (66.9 % (273/408)) (p < 0.001). The proportion of interviews with the participant answering alone or mainly alone was significantly higher in DK-1911 (77 %) than in DK-1910 (56 %), and the proportion living in nursing home was significantly lower (44 vs. 54 %, respectively). Higher proportions of DK-1911 independently performed all activities of daily living (ADL) compared to DK-1910, but only significantly for toileting, bathing, and feeding (all p < 0.01). Mini-mental state examination (MMSE) score was higher in DK-1911 than in DK-1910 (23.5 vs. 21.0; p < 0.001). Handgrip strength, gait speed, and chair stand were almost similar. DK-1911 participants had significantly better one-year survival than DK-1911 non-participants and DK-1910 participants and non-participants (p = 0.001). These results suggest that lower participation rate entails selection towards healthier participants in terms of ADL and cognitive functioning. Caution is warranted when comparing studies of centenarians with different participation rates, design, and interviewer mode, and further studies of these methodological issues are required. 相似文献
178.
Risk factors of fibrosis in alcohol-induced liver disease 总被引:17,自引:0,他引:17
Raynard B Balian A Fallik D Capron F Bedossa P Chaput JC Naveau S 《Hepatology (Baltimore, Md.)》2002,35(3):635-638
In patients with nonalcoholic steatohepatitis (NASH), age, obesity, and diabetes mellitus are independent predictors of the degree of fibrosis. The relative risk for fibrosis adjusted for sex was also associated with increasing grade of Perls stain. The aim of this study was to determine whether the risk factors for fibrosis described in NASH are also risk factors in alcohol-induced liver disease. A total of 268 alcoholic patients with negative hepatitis B virus and hepatitis C virus serology underwent liver biopsy. Fibrosis was assessed semiquantitatively by a score fluctuating between 0 to 8. Liver iron overload was assessed by Perls staining and graded in 4 classes. We have used multivariate regression with partial correlation analysis to assess the variability of fibrosis score according to the value of 7 variables: sex, age, body mass index (BMI) in the past year before the hospitalization when the patient was asymptomatic, daily alcohol intake over the past 5 years, total duration of alcohol abuse, Perls grade, and blood glucose level. In the multivariate regression, fibrosis score was positively correlated with age (P =.001), BMI (P =.002), female sex (P <.05), Perls grade (P <.05), and blood glucose level (P <.05). Twenty percent of the variability of fibrosis score was explained by the 7 variables. In conclusion, after adjustment for daily alcohol intake and total duration of alcohol abuse, BMI, Perls grade, and blood glucose are also independent risk factors for fibrosis in alcohol-induced liver disease, raising therapeutic implications for the management of these patients. 相似文献
179.
Miche E Radzewitz A Notohamiprodjo G Baller D Kloppe A Eckert S Gleichmann U 《European journal of heart failure》2002,4(4):431-438
BACKGROUND: The rate constant for global fatty acid influx (k(1)) was studied in 12 male patients with dilated cardiomyopathy (DCM). METHOD: 10 normal subjects served as controls. 201-Thallium (201TI) and [123I]-phenyl-pentadecanoic acid (IPPA) were administered during bicycle exercise under fasting conditions. RESULTS: All patients showed non-homogeneous tracer uptake defects for 201TI and IPPA. k(1) was significantly higher in DCM patients than controls. k(1) showed significant inverse correlation between cardiac index, left-ventricular ejection fraction, left-ventricular enddiastolic pressure and echocardiographic left-ventricular ejection fraction. CONCLUSION: We presume that an increased regional rate constant of IPPA influx into the myocardial tissue in patients with DCM reflects a compensatory mechanism of altered myocardium. 相似文献
180.
Transcriptional regulation of phagocytosis-induced membrane biogenesis by sterol regulatory element binding proteins 下载免费PDF全文