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11.
We tested the effects of a DNA topoisomerase inhibitor (camptothecin; CPT) on the transduction efficiency of AAV vectors in cultured human airway epithelial cells. The cells were treated with CPT for 24 hours, then exposed to AAV-CMV-LacZ for 1 hour at different multiplicities of infection (moi). Transduction efficiency of AAV vectors was assessed using X-gal staining as the percentage of LacZ-expressing cells. The transduction efficiency was approximately 1.5 to 10 fold increased by treatment with CPT prior to AAV vector exposure. However, treatment with CPT after AAV vector infection did not enhance the transduction efficiency of the vectors. These results suggest that pre-treatment with CPT increases the transduction efficiency of AAV vectors, probably by nodulating cellular function.  相似文献   
12.
Reappraises the principal theory on the azimuth displacement of the synthetic aperture radar (SAR) image of a point scatterer moving in the range direction with a constant velocity. New results are presented which describe the dependence of the image shift on the processor focal setting. It is shown that, provided the bandwidth of the processor is greater than or comparable to the bandwidth of the signal, there is a strong dependence of the azimuth image shift on the processor focusing. Simple geometric illustrations based on the optical processor are provided to interpret the effects  相似文献   
13.
This is a phase II study to evaluate the efficacy and toxicity of short-course carboplatin in advanced-stage nasopharyngeal carcinoma (NPC). Thirty-three previously untreated stage III-IV NPC patients were studied. Carboplatin was given as a rapid intravenous injection every 3 weeks. The dose of carboplatin was calculated according to the individual patient's creatinine clearance and desired platelet nadir of 75,000/microliter according to the Egorin formula. Response and toxicity were evaluated. Thirty-two patients were evaluated for response. The median age was 54 years, range 30-70 years. Twenty-four patients had local regional disease and 8 patients had metastatic disease. The median dose of carboplatin given was 415 mg/m2 (range 91-791 mg/m2). Fourteen (44%) patients had a partial response with a 95% confidence interval of 26-62%. Fifteen (47%) patients had stable disease and 3 (9%) progressive disease. The overall median survival rate was not reached at 43 months. Overall toxicity was tolerable. Grade III-IV myelosuppression occurred in 4 (12%) patients. There were no other major toxicity- or treatment-related deaths. We conclude that carboplatin has a significant anticancer effect in advanced NPC. Thus carboplatin combination chemotherapy for the treatment of NPC is worthy of future clinical investigations.  相似文献   
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15.
Tatsuro Ouchi 《Polymer》2003,44(14):3927-3933
Polylactide (PLA)-grafted polysaccharides with various lengths and numbers of graft chains were synthesized using a trimethylsilyl protection method. The properties of the cast films prepared from graft-copolymers were investigated through thermal and dynamic mechanical analyses. The graft-copolymer films exhibited a lower glass transition temperature (Tg), melting temperature, and crystallinity, and higher viscosity properties compared to PLA films. Moreover, the usefulness of graft-copolymer as a plasticizer was investigated with 1:4 blend films prepared from the graft-copolymers and PLA. The blend films showed lower Tg and crystallinity, and higher viscosity properties compared to PLA films.  相似文献   
16.
It has been suggested that pulmonary rehabilitation compined with inspiratory muscle training (IMT) might improve pulmonary function and respiratory muscle strength in elderly patients with chronic obstructive pulmonary disease (COPD). To test this hypothesis, inspiratory muscle strength (PImax), expiratory muscle strength (PEmax) and resting pulmonary function were measured in 13 elderly patients with COPD (aged 70.3 +/- 2.7 years). Inspiratory muscle training (IMT) was performed for 15 min twice a day, using a pressure threshold device, for a total of 12 weeks. The inspiratory threshold was set at 15% of maximal inspiratory pressure (PImax) for each individual. Pulmonary rehabilitation was performed for 12-h sessions over a 12-week period. Patients with COPD were assigned randomly to two groups: pulmonary rehabilitation combined with IMT (group A) (n = 7), and conventional pulmonary rehabilitation only (group B) (n = 6). Functional residual capacity (FRC) decreased significantly from 4.3 +/- 0.4 L at baseline to 3.9 +/- 0.4 L after rehabilitation (p < 0.01), Vp significantly increased from 4.6 +/- 0.8 L/sec at baseline to 5.1 +/- 0.7 L/sec after rehabilitation (p < 0.05) and the PImax increased significantly from 51.5 +/- 5.4 cmH2O at baseline to 80.9 +/- 7.0 cmH2O after rehabilitation (p < 0.02) in group A. However, these variables did not change in group B. There was no improvement in the 10-minutes walking distance of group A, but there was a significant increase in that of group B. It can be concluded that pulmonary rehabilitation combined with IMT improves pulmonary function and inspiratory muscle strength in elderly patients with COPD.  相似文献   
17.
The activities of fourteen kinds of catalysts for the hydrocracking of Taiheiyo coal were examined by a high pressure differential thermal analytical method. Exothermic peaks appeared at low temperatures (420–430°C) when MoO3TiO2, NiY zeolite and CoY zeolite were used as catalysts, indicating that these catalysts are highly active compared with other catalysts including MoO3CoOAl2O3. The qualitative analysis of gas and liquid products revealed that MoO3TiO2 and CoY are good catalysts for the liquefaction reaction. The hydrogenation ability of the catalyst is concluded to be more important than its acidic property.  相似文献   
18.
Four coals with similar ultimate analyses were Soxhlet-extracted with pyridine before and after heat treatment at 400 °C and with quinoline at 350 °C. Pyridine extraction yield tended to be proportional to log maximum fluidity (MF), but with some discrepancies. Quinoline extraction yield was more nearly proportional to log MF. However, the best correlation with log MF was obtained for quinoline extraction yield corrected for inert content.  相似文献   
19.
For a recently proposed perpendicular recording system, a composite anisotropy medium has been developed to improve the recording sensitivity of the perpendicular recording head. The medium is composed of a Fe-Ni soft magnetic film and a Co-Cr perpendicular anisotropy film, which are successively deposited on a base by an r. f. sputtering. By using the new double layer medium, an extremely high recording sensitivity could be obtained, compared with the single layer Co-Cr medium. The recording current needed to saturate the double layer film decreased to one-tenth of that for the single layer Co-Cr film. Although the Fe-Ni layer was soft magnetic material, neither deterioration of the frequency response nor peak shift was observed for the double layer film. The reproduction with a perpendicular head was also investigated, and a high output voltage and a high signal-to-noise ratio were obtained.  相似文献   
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