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21.
Continuous thoracic epidural anesthesia (T4/5) using 4-5 ml.h-1 of 1.5% lidocaine with 1:200,000 epinephrine and inhaled anesthesia using nitrous oxide, oxygen and sevoflurane were performed in two patients, (40 and 22 yr-old females) with myasthenia gravis. This combined anesthetic technique provided muscle relaxation for endotracheal intubation and optimal operating conditions, including muscle relaxation and stability of hemodynamics during transsternal thymectomy. Further, continuous epidural anesthesia using 4 ml.h-1 of 0.25% bupivacaine provided postoperative pain relief without other analgesics and stable postoperative respiratory conditions. In conclusion, we confirm the benefits of this technique which provides not only safe and stable conditions during the surgery, but also an improved comfort for patients in the postoperative period following transsternal thymectomy for myasthenia gravis.  相似文献   
22.
We investigated the intracellular signaling of OX40, a member of the tumor necrosis factor receptor family. Activation of NF-kappaB in OX40-transfected HSB-2 cells was detected by electrophoretic mobility shift assay within 30 min after the binding of the ligand gp34. In vitro binding experiments showed that tumor necrosis factor receptor-associated factor (TRAF) 1, TRAF2, TRAF3, and TRAF5 but not TRAF4 associated with glutathione S-transferase-OX40 fusion protein. The cotransfection experiments using human embryo kidney cell derived HEK 293T cells showed that TRAF2, TRAF3, and TRAF5 associated with OX40 in vivo. Studies with OX40 deletion mutants demonstrated that the cytoplasmic portion consisting of amino acid sequence 256-263 (GGSFRTPI) was required for the association with TRAFs and NF-kappaB activation. The introduction of the dominant negative mutants of TRAF2 and TRAF5 into HSB-2-OX40 cells suppressed NF-kappaB activation in a dose-dependent manner. In addition, the introduction of TRAF3 together with the dominant negative mutants of TRAF2 or TRAF5 further reduced NF-kappaB activation. These results indicate that the NF-kappaB activation resulting from OX40 stimulation is mediated by both TRAF2 and TRAF5, and is likely to be negatively modulated by TRAF3.  相似文献   
23.
A lightning strength parameter α (denoted as LSP or LAIDO), which is used for characterizing the phenomena of lightning activity, has been proposed, where α is defined by the characteristic energy obtained from the energy distribution of a radiated field component E in the electrostatic field changes produced by lightning discharge. Here, it is observed that the energy distribution of Eγ components is Maxwellian type. To prove more clearly the forementioned assumption from another viewpoint, changes of the amplitudes of the electrostatic field component ES were measured and their distribution functions constructed. In the cloud-to-ground lightning discharges, the ES components have a positive sign in the changes. However, those changes in the intercloud discharges are observed with either a negative or positive change depending on the distance between the striking point and the observation site. Therefore it is necessary to sum the numbers of occurrences of both positive and negative components for constructing an energy distribution of the ES component. A fieldmill and a pair of doughnut-shaped electrostatic antennas are used in measuring the changes of the ES component. As a result it is found that the changes of the amplitudes of the ES components have a Maxwelliantype energy distribution. A characteristic energy β is defined which is obtained from the component of the electrostatic fields as a measure of LSP. Based on comparison of α and β it is clarified that β has the same characteristic nature with α. The lightning activity could be estimated from β.  相似文献   
24.
A pilot-plant study was conducted in the Republic of Croatia to determine the applicability of ozonation for inactivation of non-indigenous species and to provide necessary information regarding use of ozone as a ballast water treatment option. Nauplii of the brine shrimp Artemia salina were used as model organisms to investigate the efficacy of ozonation at three different ozone dosages (2.4, 3.7 and 10.9 mg L?1). Mortality of Artemia nauplii at 98.6%, was achieved after 3 h of exposure in ozone-treated water with the highest ozone dosage. Our results indicated that ozonation is a promising treatment for controlling non-indigenous and potentially invasive species; however, to draw more general conclusions, several species with higher level of resistance to ozone are required and will be studied in the future.  相似文献   
25.
The effect of domestically-manufactured excimer laser with adjunctive balloon angioplasty in achieving revascularization and reduction of residual stenosis was assessed. 20 femoral arteries with thrombosis and occlusion from 12 dogs were subject to angiography. At first excimer laser angioplasty was done followed by balloon angioplasty. The diameter and residual stenosis of revascularized vessel were measured. The result showed that 17 out of 20 vessels (85%) were revascularized. The diameter of revascularized vessel by excimer laser were 1.22 +/- 0.14 mm, while residual stenoses were 54% +/- 5%. After adjunctive balloon angioplasty the diameter and residual stenoses were 2.04 +/- 0.16 mm and 20% +/- 7% respectively (P < 0.05 and P < 0.01). Complication in form of vasoperforation occurred in 3/20 vessels (15%). It is concluded that China- manufactured excimer laser angioplasty is effective when used for revascularization. While the reduction of narrowing and residual stenoses was enhanced after adjunction of balloon angioplasty. This method can be employed in treating peripheral occlusive disease effectively and safely.  相似文献   
26.
In order to understand an apparent discrepancy of concentration of constituent elements in the quantitative analysis of thin KCl crystals with an energy dispersive X-ray analyzer, which has been partly explained by fluorescent X-ray excitation, more detailed experiments were carried out on binary alkali halides and tricomponent amorphous material by changing the azimuthal angle. Intensity ratios of X-rays from the constituent elements in KCl and KBr single crystals varied considerably according to the rotation of the specimens. The observed differences between maximum and minimum intensity ratios were 15% for a thin KCl crystal about 100 nm thick and 20% for a bulk KCl crystal, which corresponded to 4.1% and 4.5% differences in atomic concentration, respectively. It was ascertained that for amorphous materials such as Co87Zr5Nb8, such a variation of the intensity ratio of X-rays was not observed. It is thus proved that the variations of the intensity ratios of X-rays from the constituent elements with azimuthal angle for KCl and KBr are attributed to the diffraction effect of characteristic X-rays generated in crystalline specimens. This effect, which is the same as that in the production of Kossel patterns, is one of the essential factors limiting the accuracy of the analysis.  相似文献   
27.
In order to investigate the validity and application of a finite element creep analysis program developed for the design of PCRV, a creep test was carried out on a scale model of a PCRV and the results were compared with those from numerical analysis. Based on the rate of flow method, the creep strain of concrete is divided into two components: flow strain (irreversible creep) which is assumed to be a linear function in the logarithmic scale of t, and delayed elastic strain (reversible creep) which is expressed as an exponential function of flow strain. The analysis program is based on the finite element method in which triangular constant strain elements for solids of revolution are used and the time-step analysis function, in the form of the initial strain method, is provided. In the analysis of the PCRV model constant creep Poisson's ratios of 0.17, 0.3 and 0.5 are assumed for the purpose of comparison. The constitutive model based on the rate of flow method satisfactorily modelled the uniaxial creep behaviour of test cylinders and the computed strains simulated the characteristics of the strain histories of the PCRV model fairly well in the qualitative sense.  相似文献   
28.
The migration rate of lenticular voids in uranium dioxide was measured in convection with an analysis of structural changes behavior in the irradiated fuel. The lenticular voids were fabricated in the interface of two thin discs of high density UO2 by contacting and subsequently resintering the polished faces of the discs. The specimen was heated under the influence of a temperature gradient of 3000–5000°C/cm for 1–9 h, using an induction furnace. The migration rates were measured on the micrographs of the specimen after heating, and the results obtained showed good agreement with the theoretical values derived from Sens' model.  相似文献   
29.
Cyclodextrin-mediated capillary isotachophoresis (ITP) in cationic regime of the separation was developed for the separation and quantitation of alkylamine antihistamine dimethindene (DIM) and pheniramine (PHM) enantiomers in various pharmaceutical preparations (capsules, oral drops, gel, granulated powder). Several electrolyte systems of different compositions and pH were examined. The optimized chiral ITP electrolyte system was consisted of 10 mmol/L potassium acetate adjusted to pH 4.8 with acetic acid, containing 4 mmol/L negatively charged CE-β?CD (chiral selector) as the leading electrolyte with electroosmotic flow (EOF) suppressing additive, 0.2% (w/v) methylhydroxyethylcellulose (m-HEC), and 5 mmol/L β-alanine as the terminating electrolyte. The proposed electrophoretic method was successfully validated. It was convenient for the sensitive, simple, rapid, and highly reproducible assay of these antihistamine enantiomers. The calibration graphs relating the ITP zone length to the concentration of DIM and PHM enantiomers were rectilinear (r = 0.999) in the range 40.0–200.0 mg/L of each enantiomer. The relative standard deviations (RSD) were 0.75% for DIM(1), 0.63% for DIM(2), 1.05% for PHM(1), and 0.83% for PHM(2) (n = 6) when determining 100 mg/L DIM and PHM, respectively, standard solutions. According to the validation procedure based on the standard addition technique the recoveries were 97.66–98.34%. Good quantitation was obtained in short analysis time (a single analysis took about 12 min). The minimal sample pretreatment and low running costs make the proposed ITP method a good alternative to commonly used analytical methods (CZE, HPLC). The obtained results suggest that the proposed method is suitable for routine assay of dimethindene and pheniramine enantiomers in various pharmaceuticals.  相似文献   
30.
Hybrid Langmuir-Blodgett films consisting of an amphiphilic hemicyanine derivative and a smectite clay have been fabricated employing a clay suspension as the subphase. This hybridization was demonstrated to be a convenient and effective means of achieving complete disaggregation of dye chromophores in a Langmuir-Blodgett film without reducing chromophore density in the two-dimensional lattice. UV-visible electronic absorption and optical second-harmonic generation measurements indicated that the molecular alignment in the films was stabilized by the hybridization.  相似文献   
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