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排序方式: 共有6771条查询结果,搜索用时 15 毫秒
51.
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
52.
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
53.
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
54.
55.
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
56.
57.
Tien-Yuan?Wu Ying?Huang Chengyue?Zhang Zheng-Yuan?Su Sarandeep?Boyanapalli Tin?Oo?Khor Hu?Wang Hongxia?Lin Murugesan?Gounder Leonid?Kagan Ioannis?P.?Androulakis Ah-Ng?Tony?KongEmail author 《Journal of pharmacokinetics and pharmacodynamics》2015,42(4):401-408
3,3′-Diindolylmethane (DIM) has been investigated as a potential anti-cancer chemopreventive agent in many preclinical and clinical studies. In this study, we sought to characterize the pharmacokinetics of DIM and to build a pharmacokinetic (PK) and pharmacodynamic (PD) model of the DIM-induced gene expression of phase II drug metabolizing enzymes (DME), which potentially links DIM’s molecular effects to its in vivo chemopreventive efficacy. DIM (10 mg/kg) was administered intravenously (i.v.) to male Sprague–Dawley rats and blood samples were collected at selected time points for 48 h. The plasma concentration of DIM was determined using a validated HPLC method. The mRNA expression of NQO1, GSTP1 and UGT1A1 in blood lymphocytes was measured using quantitative PCR. An indirect response model was employed to relate the concentration of DIM to the expression of the genes NQO1, GSTP1 and UGT1A1, which were chosen as PD markers for DIM. After i.v. administration, the plasma concentration of DIM declined quickly, and the expression of target genes increased significantly, peaking at 1–2 h and then returning to basal levels after 24 h. The parameters in the PK–PD model were estimated. The PK–PD model aptly described the time delay and magnitude of gene expression induced by DIM. Our results indicate that DIM is effective at inducing various phase II DME, which are capable of detoxify carcinogens. This PK–PD modeling approach provides a framework for evaluating the acute effects of DIM or other similar drugs in clinical trials. 相似文献
58.
Doundoulakis Ioannis Gavriilaki Maria Tsiachris Dimitris Arsenos Petros Antoniou Christos-Konstantinos Dimou Smaro Soulaidopoulos Stergios Farmakis Ioannis Akrivos Evangelos Stoiloudis Panagiotis Notas Konstantinos Kimiskidis Vasilios K. Giannakoulas George Paraskevaidis Stylianos Gatzoulis Konstantinos A. Tsioufis Konstantinos 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2022,36(5):951-958
Cardiovascular Drugs and Therapy - Atrial high-rate episodes (AHREs) recorded with cardiac implantable electronic devices (CIEDs) have been associated with the development of clinical atrial... 相似文献
59.
Brandon N. Nicolay Paul S. Danielian Filippos Kottakis John D. Lapek Jr Ioannis Sanidas Wayne O. Miles Mantre Dehnad Katrin Tsch?p Jessica J. Gierut Amity L. Manning Robert Morris Kevin Haigis Nabeel Bardeesy Jacqueline A. Lees Wilhelm Haas Nicholas J. Dyson 《Genes & development》2015,29(17):1875-1889
60.
Koutroubakis IE Petinaki E Dimoulios P Vardas E Roussomoustakaki M Maniatis AN Kouroumalis EA 《International journal of colorectal disease》2003,18(3):254-259
BACKGROUND AND AIMS: Initiation of a fibrotic process has been suggested as part of the intestinal response to chronic inflammation in inflammatory bowel disease. YKL-40 has been proposed as a new serum marker of fibrosis. We studied compared the serum levels of YKL-40 in patients with ulcerative colitis or Crohn's disease with inflammatory and healthy controls. PATIENTS AND METHODS: YKL-40 serum levels were measured in 179 patients with inflammatory bowel disease (94 ulcerative colitis, 85 Crohn's disease), in 23 with intestinal inflammation of other causes, and 70 matched healthy controls using a commercially available enzyme-linked immunosorbent assay. YKL-40 levels were assessed in terms of disease activity, type and localization. RESULTS: Mean serum YKL-40 levels were 102.6+/-82.7 ng/ml in ulcerative colitis patients and 112.2+/-83.7 ng/ml in Crohn's disease patients, significantly higher than in healthy controls (64.1+/-21.4 ng/ml) but not significantly different from inflammatory controls (77.8+/-23.1 ng/ml). Disease activity and C-reactive protein levels were significantly correlated with YKL-40 levels in both ulcerative colitis and Crohn's disease. Crohn's disease patients with ileum localization had significantly higher YKL-40 levels than those with ileocolonic or colonic disease. Patients with stenotic disease had mean YKL-40 levels not significantly different than those with nonstenotic disease. CONCLUSION: Serum levels of YKL-40 are increased in patients with inflammatory bowel disease, and this is associated with the inflammatory process rather than with the degree of fibrosis. 相似文献