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排序方式: 共有6792条查询结果,搜索用时 15 毫秒
41.
Schulpis KH Papassotiriou I Vounatsou M Karikas GA Tsakiris S Chrousos GP 《The Journal of clinical endocrinology and metabolism》2004,89(8):3983-3987
Patients with phenylketonuria (PKU) have a diet-controlled deficiency in the conversion of phenylalanine (Phe) to tyrosine (Tyr), leading to decreased production of noradrenaline, adrenaline, and dopamine. Poor diet control results in high plasma Phe and low plasma Tyr and catecholamine concentrations. Ghrelin, a recently described gastrointestinal hormone that is elevated in the fasting state and low in the fed state, is considered a major appetite-stimulating hormone, possibly involved in the generation of obesity and insulin resistance. We evaluated morning preprandial plasma ghrelin levels in 14 diet-controlled and 15 poorly controlled PKU patients and 20 age- and body mass index (BMI)-matched healthy children (controls) and correlated its concentrations with those of Phe and catecholamines as well as with their BMI and 24-h nutrient intake. Plasma ghrelin levels were measured by RIA, plasma catecholamine concentrations were determined by HPLC with electrochemical detection, and Phe and Tyr levels were measured in an amino acid analyzer. The ghrelin concentration (744 +/- 25 ng/liter) in diet-controlled patients did not differ from that in controls (802 +/- 26 ng/liter; P > 0.05). On the contrary, the ghrelin concentration was significantly reduced in poorly controlled patients (353 +/- 23 ng/liter; P < 0.0001). Ghrelin correlated negatively with Phe in all three groups, whereas it correlated positively with catecholamine levels and energy intake and negatively with BMI only in diet-controlled patients and controls. We conclude that ghrelin secretion may receive positive direct or indirect input from catecholamines. The absence of a correlation between ghrelin and catecholamines, energy intake, or BMI in PKU patients on an inadequate diet may be due to dysregulation of their neuroendocrine system and might be affected by high Phe levels in the stomach and/or central nervous system. 相似文献
42.
Michael L Sion Melina C Armenaka Ioannis Georgiadis Georgios Paraskevopoulos Ioannis Nikolaidis 《Thyroid》2004,14(9):786-788
Thyroid invasion by Aspergillus spp. can occur with invasive aspergillosis, although it is rarely diagnosed antemortem. We describe a case of multiple thyroid abscesses from A. fumigatus that caused esophageal obstruction in a patient with myelodysplasia. Despite aggressive antifungal treatment, the outcome was rapidly fatal. 相似文献
43.
44.
NOD2 insertion mutation in a Cretan Crohn's disease population 总被引:5,自引:0,他引:5
Roussomoustakaki M Koutroubakis I Vardas EM Dimoulios P Kouroumalis EA Baritaki S Koutsoudakis G Krambovitis E 《Gastroenterology》2003,124(1):272-3; author reply 273-4
45.
Panayota Flevari George Theodorakis Ioannis Paraskevaidis Fotis Kolokathis Anna Kostopoulou Dionyssios Leftheriotis Christos Kroupis Efthimios Livanis Dimitrios T Kremastinos 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(1):44-50
AIMS: To study the effect of cardiac resynchronization therapy (CRT) on coronary and peripheral arterial circulation and to assess whether their changes are related to the improvement in patients' functional capacity and prognostically important biochemical markers. METHODS AND RESULTS: Twenty-five patients were studied (New York Heart Association classes III and IV, left ventricular ejection fraction <35%, QRS>120 ms, mean age 66 +/- 2.1 years). Coronary blood flow (CBF), forearm blood flow (FBF), and their reserve were measured by transoesophageal echocardiography (in cm/s) and venous occlusion plethysmography (in mL/100 mL/min) at baseline and following 3 months of CRT. N-terminal-pro-brain natriuretic peptide (Nt-pro-BNP) and serum adhesion molecules, sICAM-1 and sVCAM-1 levels were also assessed. CRT induced a non-significant increase in resting CBF (baseline vs. CRT: 52.1 +/- 5.5 vs. 58.2 +/- 3.6, P: NS), whereas hyperaemic CBF was increased by CRT (baseline vs. CRT: 67.8 +/- 6.8 vs. 79.8 +/- 6.2, P < 0.05). Significant increases were observed in resting FBF (baseline vs. CRT: 1.6 +/- 0.2 vs. 2.6 +/- 0.2, P < 0.05) and hyperaemic FBF (baseline vs. CRT: 2.1 +/- 0.2 vs. 3.2 +/- 0.3, P < 0.05). The per cent difference in hyperaemic FBF was related to the per cent change in Nt-pro-BNP (r = -0.71, P < 0.05) and the per cent improvement in exercise duration (r = 0.80, P < 0.05). CONCLUSION: CRT induces favourable changes in coronary and peripheral arterial function. Changes in peripheral blood flow are related to patients' improvement and may be prognostically significant. 相似文献
46.
Bamias A Basdanis G Xanthakis I Pavlidis N Fountzilas G 《Journal of gastrointestinal cancer》2005,36(1):29-38
Background. Although the TNM system is useful in predicting survival in resected colorectal cancer, heterogeneity within the same stages
regarding prognosis exists. We are presenting a pooled analysis of prognostic factors from two randomized studies of adjuvant
treatment conducted by the Hellenic Cooperative Oncology Group.
Patients and Methods. Patients with stage II or III colon (n=279) or rectal (n=220) cancer were included in this analysis. Following surgery, patients received: 5-fluorouracil/leucovorin (5-FU/LV) (n=135), 5-FU/LV and interferon Alfa-2a (IFNA-2a) (n=138), 5-FU/LV and pelvic chemoradiotherapy (n=106), and pelvic chemoradiotherapy alone (n=108).
Results. Median follow up was 92 mo. The number of involved lymph nodes (LNs), tumor differentiation, and the presence of regional
implants were independent prognostic factors for both OS and TTP, while nerve invasion was only significant for TTP. Patients
were stratified into three prognostic groups (low-risk: no LNs and grade 1/2; high-risk: >3 LNs and grade 3/4; intermediate-risk:
remaining patients) with distinct differences in 5-yr survival (84.7% vs 57.6% vs 32.4%) and 5-yr TTP (81.2% vs 54.5% vs 28.6%).
Conclusion. The combination of clinicopathological prognostic factors can be more informative than the traditional TNM staging system.
Such stratification may be necessary in randomized trials and could be useful in deciding the most appropriate adjuvant treatment
strategies. 相似文献
47.
Kister J Baudin-Creuza V Kiger L Préhu C Papassotiriou I Riou J Galactéros F Wajcman H 《Blood cells, molecules & diseases》2005,34(2):166-173
Hb Montfermeil [beta130(H8) Tyr-->Cys] is a high oxygen affinity variant causing erythrocytosis. The cysteine replacement is buried in the inside of the beta chain where it alters the interactions between helix A and H, with a further effect on helix E. This position has already been proposed to contribute to the difference in oxygen affinity between human and bovine hemoglobins. Three dimensional structural considerations and comparison of the functional behavior of other variants suggest that this region is an important determinant of the intrinsic oxygen affinity of the hemoglobin molecule. 相似文献
48.
49.
Erez Peterfreund Ofir Lindenbaum Felix Dietrich Tom Bertalan Matan Gavish Ioannis G. Kevrekidis Ronald R. Coifman 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(49):30918
We propose a local conformal autoencoder (LOCA) for standardized data coordinates. LOCA is a deep learning-based method for obtaining standardized data coordinates from scientific measurements. Data observations are modeled as samples from an unknown, nonlinear deformation of an underlying Riemannian manifold, which is parametrized by a few normalized, latent variables. We assume a repeated measurement sampling strategy, common in scientific measurements, and present a method for learning an embedding in that is isometric to the latent variables of the manifold. The coordinates recovered by our method are invariant to diffeomorphisms of the manifold, making it possible to match between different instrumental observations of the same phenomenon. Our embedding is obtained using LOCA, which is an algorithm that learns to rectify deformations by using a local z-scoring procedure, while preserving relevant geometric information. We demonstrate the isometric embedding properties of LOCA in various model settings and observe that it exhibits promising interpolation and extrapolation capabilities, superior to the current state of the art. Finally, we demonstrate LOCA’s efficacy in single-site Wi-Fi localization data and for the reconstruction of three-dimensional curved surfaces from two-dimensional projections. 相似文献