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排序方式: 共有254条查询结果,搜索用时 8 毫秒
51.
Mohammad Alidoosti Mojtaba Salarifar Ali Mohammad Haji Zeinali Seyed Ebrahim Kassaian Maria Raissi Dehkordi 《BMC cardiovascular disorders》2007,7(1):1-8
Background
There have been few prospective studies examining the utility of routine exercise treadmill testing (ETT) early after percutaneous coronary intervention (PCI). The objective of this study was to examine the impact of a routine ETT strategy early after PCI on follow-up cardiac events and procedures.Methods
We examined 136 patients who underwent routine ETT at 6 weeks post-PCI in the ADORE trial. The ETT was classified as positive, indeterminate, or negative. The Duke Treadmill Score (DTS) was calculated for all patients. Follow-up occurred at 9 months.Results
ETT results at 6 weeks were: 32 (23.5%) positive, 24 (17.6%) indeterminate and 80 (58.8%) negative. At 9 months, the composite event rate was 21.9% in those with a positive ETT, 20.8% in those with an indeterminate ETT and 12.5% in those with a negative ETT (p = 0.25 positive vs. negative ETT). The sensitivity of early ETT for predicting clinical events was 41.2%, the specificity was 73.3%, the positive predictive value was 21.9% and the negative predictive value was 87.5%. At 9 months, the cardiac procedure rate was 18.8% in those with a positive test, 13.0% in those with an indeterminate test, and 6.3% in those with a negative test (p = 0.07 positive vs. negative ETT). In a multivariate logistic regression model, coronary stenting during PCI and a ≥ 85% MPHR achieved were found to be inversely associated with clinical events. However, the DTS did not independently predict clinical events.Conclusion
Although the statistical power of the study was limited by the small number of clinical events (particularly MI and death), the results of this study support the ACC/AHA guidelines that exercise treadmill testing should not be used routinely after PCI. 相似文献52.
Hiraoui M Haji L Guendouz M Lorrain N Moadhen A Oueslati M 《Biosensors & bioelectronics》2012,36(1):212-216
Recently, we demonstrated that Anti Resonant Reflecting Optical Waveguide (ARROW) based on porous silicon (PS) material can be used as a transducer for the development of a new optical biosensor. Compared to a conventional biosensor waveguide based on evanescent waves, the ARROW structure is designed to allow a better overlap between the propagated optical field and the molecules infiltrated in the porous core layer and so to provide better molecular interactions sensitivity. The aim of this work is to investigate the operating mode of an optical biosensor using the ARROW structure. We reported here an extensive study where the antiresonance conditions were adjusted just before the grafting of the studied molecules for a given refractive index range. The interesting feature of the studied ARROW structure is that it is elaborated from the same material which is the porous silicon obtained via a single electrochemical anodization process. After oxidation and preparation of the inner surface of porous silicon by a chemical functionalization process, bovine serum albumin (BSA) molecules, were attached essentially in the upper layer. Simulation study indicates that the proposed sensor works at the refractive index values ranging from 1.3560 to 1.3655. The experimental optical detection of the biomolecules was obtained through the modification of the propagated optical field and losses. The results indicated that the optical attenuation decreases after biomolecules attachment, corresponding to a refractive index change Δn(c) of the core. This reduction was of about 2 dB/cm and 3 dB/cm for Transverse Electric (TE) and Transverse Magnetic (TM) polarizations respectively. Moreover, at the detection step, the optical field was almost located inside the core layer. This result was in good agreement with the simulated near field profiles. 相似文献
53.
为研究维药瘤果黑种草籽的化学成分,采用硅胶、ODS柱色谱等方法分离纯化,分离并鉴定了16个化合物,利用理化性质及波谱方法鉴定化学成分的结构分别为:Nigeglanine(1)、附子碱(2)、L-色氨酸(3)、L-色氨酸甲酯(4)、5,7-二羟基-异苯并呋喃酮(5)、豆甾醇(6)、豆甾醇-3-O-β-D-葡萄糖苷(7)、β-谷甾醇(8)、β-胡萝卜苷(9)、亚油酸(10)、邻苯二甲酸二丁酯(11)、棕榈酸(12)、十六烷酸1-甘油酯(13)、硬酯酸(14)、硬酯酸2-甘油酯(15)和蔗糖(16)。其中化合物3~5、7、9、11和15为首次从该种药材中得到。 相似文献
54.
Ryota Nakajima Teruaki Yoshida Bin Abdul Rahim Azman Kassim Zaleha Bin Haji Ross Othman Tatsuki Toda 《Aquatic Ecology》2009,43(4):815-823
In situ mucus release by Acropora nobilis and degradation of mucus from A. nobilis and Acropora formosa, by heterotrophic bacteria were investigated at Bidong and Tioman Island, Malaysia. Mucus release rate for A. nobilis was on average 38.7 ± 35.2 mg C m−2 h−1, of which ca. 70% consisted of dissolved organic carbon (DOC) and 30% particulate organic carbon (POC). In the mucus degradation
experiment, seawater-mucus mixtures were incubated and compared with control runs for 24 h. Bacterial abundance in the seawater-mucus
mixture increased significantly and coincided with a decline in DOC concentration. In controls, bacteria and DOC did not significantly
change. The coral mucus had a high content of inorganic phosphate. It is suggested that the coral mucus rich in DOC and phosphate
can induce the high bacterial growth. 相似文献
55.
Cardiac sodium channel Markov model with temperature dependence and recovery from inactivation
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A Markov model of the cardiac sodium channel is presented. The model is similar to the CA1 hippocampal neuron sodium channel model developed by Kuo and Bean (1994. Neuron. 12:819-829) with the following modifications: 1) an additional open state is added; 2) open-inactivated transitions are made voltage-dependent; and 3) channel rate constants are exponential functions of enthalpy, entropy, and voltage and have explicit temperature dependence. Model parameters are determined using a simulated annealing algorithm to minimize the error between model responses and various experimental data sets. The model reproduces a wide range of experimental data including ionic currents, gating currents, tail currents, steady-state inactivation, recovery from inactivation, and open time distributions over a temperature range of 10 degrees C to 25 degrees C. The model also predicts measures of single channel activity such as first latency, probability of a null sweep, and probability of reopening. 相似文献
56.
57.
58.
Guang-Hui Gou Liu Liu Sardorbek Abdubakiev Xue-Lei Xin Haji Akber Aisa Jun Li 《化学与生物多样性》2023,20(1):e202200904
Piper longum is a well-known spice and traditional medicine. It was revealed to possess anti-diabetic activity, but few information about its active component and underlying mechanism could be available. In this study, retrofractamides A ( 1 ) and C ( 2 ) isolated from P. longum showed potent inhibitory activity against PTP1B. Therefore, the potential mechanism was predicted by network pharmacology and molecular docking. PI3K/AKT was obtained as the most remarkable pathway against type 2 diabetes mellitus (T2DM), and AKT1 and GSK3β were yielded as the top two core targets of retrofractamides A ( 1 ) and C ( 2 ). Molecular docking of compounds with AKT1 and GSK3β showed strong binding affinity between them. Additionally, cellular experiments with a L6 cell model was conducted to further verify the above predictions. Results indicated that retrofractamides A ( 1 ) and C ( 2 ) exerted anti-diabetic effect via activating PI3K/AKT pathway, and they promoted glucose consumption, glucose uptake, glycogen synthesis and glycolysis. 相似文献
59.
The kinetics of the uptake and efflux of 3-O-methyl-glucose in sporidia of Ustilago maydis were measured, both in active cells and in cells whose metabolic activity had been inhibited by azide and iodoacetate.The de-energized transport system proved to be carrier mediated with apparent affinity constants 13 ± 2 mM outside (K0) and 18 ± 2 mM inside (K1). The apparent maximum rate constants for the same system were 0.66 ± 0.05 mmol/l cell water per min for uptake (V+ and 0.53 ± 0.04 mmol/l cell water per min for efflux (V-. For the active system K0 = 0.08 ± 0.01, K1 > 40, V+ = 9.7 ± 0.5 and V− 1.1 ± 0.9 (in equivalent units). These results are discussed in the context of the carrier mechanism as proposed by Regen and Morgan (Regen, D.M. and Morgan, H.E. (1964) Biochim. Biophys. Acta 79, 151–166).The antifungal compound carboxin had no effect on de-energized transport but was shown to decrease both K0 and V+ in the active system. Phloretin and phlorizin were also found to be without effect on de-energized cells but the former enhanced while the latter inhibited active uptake. 相似文献
60.