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41.
This study aimed to determine whether combined examinations of myocardial 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and stress-redistribution 201Tl single-photon emission computed tomography (Tl SPECT) were useful in clarifying myocardial ischaemia and evaluating the prognosis in patients with idiopathic dilated cardiomyopathy (IDCM). Twenty-two patients with IDCM underwent echocardiography, cardiac catheterization, FDG PET, and Tl SPECT. In scintigraphic analysis, the total defect score (TDS) was semiquantitatively determined as the sum of scores of the 17 left ventricular (LV) segments with a 5-point scale (0 as normal to 4 as absent). Patients were classified according to the scintigraphic findings as follows: eight patients with small defects on Tl and FDG (TDS < or = 20) (group I), eight patients with small defects on FDG (TDS < or = 20) with FDG uptake increased relative to Tl or 'mismatch' (group II), and six patients with large defects on FDG and Tl (TDS >20) (group III). Eleven patients (50%) showed reversible defects on Tl and all showed preserved FDG uptake. The patients in group III had significantly lower LV ejection fraction (LVEF) (P<0.05, respectively) and a poorer prognosis as shown by the Kaplan-Meier event-free curve compared with those in groups I and II (P<0.01, respectively). Although patients in group II had significantly greater TDS on Tl compared with those in group I (P<0.01), no significant differences in LVEF and prognosis were found between patients in groups I and II. In multivariate analysis, a TDS on FDG revealed an independent predictor of subsequent cardiac events. In conclusion, such mismatched areas can be assumed to consist of impaired but viable myocardium, and may be associated with ischaemia of the microvasculature. Impaired myocardial glucose metabolism is a more powerful predictor of future cardiac events than perfusion abnormality in patients with IDCM.  相似文献   
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Stress granules (SGs) and processing bodies (P bodies) are cytoplasmic domains and play a role in the control of translation and mRNA turnover in mammalian cells subjected to environmental stress. Recent studies have revealed that SGs also form in the budding yeast Saccharomyces cerevisiae in response to glucose depletion and robust heat shock. However, information about the types of stress that cause budding yeast SGs is quite limited. Here we demonstrate that severe ethanol stress generates budding yeast SGs in a manner independent of the phosphorylation of eIF2α. The concentration that generated budding yeast SGs (>10%) was higher than that causing P bodies (>6%), and P bodies were assembled prior to SGs. As well as mammalian SGs, the assembly of budding yeast SGs under ethanol stress was blocked by cycloheximide. On the other hand, the budding yeast SGs caused by ethanol stress contained eIF3c but not eIF3a and eIF3b, although the eIF3 complex is a core constituent of mammalian SGs. Moreover, null mutants (pbp1Δ, pub1Δ and tif4632Δ) with a strong reduction in SG formation did not resume proliferation after the elimination of ethanol stress, indicating that the formation of budding yeast SGs might play a role in sufficient recovery from ethanol stress.  相似文献   
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  总被引:1,自引:0,他引:1  
A bacterial strain ST201 capable of degrading styrene was isolated from soil and identified as Pseudomonas putida. This strain had high tolerance to styrene and could degrade it completely in 48 h at concentrations up to 600 mg/l. P. putida ST201 was also demonstrated to degrade a mixture of benzene, toluene, ethylbenzene and p-xylene. A packed tower biofilter inoculated with P. putida ST201 was constructed which removed styrene vapor with a styrene elimination capacity of 90 g/m3.h.  相似文献   
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The structure–property relationships of polyurethane elastomer derived from liquid hydroxylterminated polybutadiene/low molecular weight aliphatic diol/diisocyanate system were studied. The effects of the amount of low molecular weight diol on the mechanical properties of elastomer were discussed on the basis of the results of the stress–strain curve, swelling, dynamic viscoelasticity, x-ray diffraction, and others. It was found that some particular combinations of low molecular weight diol and diisocyanate specifically affect the properties of elastomers. When the mechanical properties of the elastomers were plotted against the number of methylene carbons in low molecular weight diol, the characteristic zigzag patterns were obtained. These patterns were explained by the difference in the packing and the dependence of the ability of intermolecular hydrogen bonding on whether the number of the methylene carbons was even or odd. This assumption was confirmed by x-ray diffraction.  相似文献   
46.
For a bubble column (BC) treating foaming liquids, the characteristics of a rotating-disk mechanical foam-breaker (MFRD) fitted to the BC were examined. The foaming behaviour of the BC and the foam-breaking behaviour of the MFRD under various operating conditions were related to the changes in liquid hold-up in the foam. The gas hold-up in a mechanical foam-control system (MFS) with the MFRD was confirmed to be greater than the gas hold-up in a non-foaming system (NS) including antifoam agent (AF). Comparison of the volumetric mass transfer coefficient between the MFS and the non-foaming system, in terms of the specific power input, also demonstrated the superiority of mechanical foam control for oxygen transfer performance.  相似文献   
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Data evaluation methods have wide adaptations, such as feedbacks to PV system operation management and design. The authors have already developed sophisticated verification method (SV method) of PV systems, which is a simple evaluation method to identify six kinds of system loss rates using basic information and simple four measurable data. This time, the authors introduced quality diagnosis to our previous model for compensating the measurement errors in field data, and improved the algorithm of the model. Consequently, validity of the evaluation result became better than the previous model.  相似文献   
50.
We developed a fab-wide advanced process control system to control the critical dimension (CD) of gate electrode length in semiconductors. We also developed a model equation that predicts the gate CD by considering the structures of gate electrode and shallow trench isolation. This prediction model was also used to perform a factor analysis of gate CD variation. The effectiveness of the model in controlling feedforward was evaluated by both simulation and experiment. The CD variation of the wafers was improved from 8.9 nm in its 3 sigma without control to 3.5 nm with lot-to-lot feedforward control.  相似文献   
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