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排序方式: 共有393条查询结果,搜索用时 281 毫秒
71.
V. I. Malyugin D. V. Kiesewetter E. O. Boldyreva A. V. Modanov 《Technical Physics Letters》2008,34(9):754-756
A spectral-correlation diagnostic method has been used for determining the linear dimensions of inhomogeneities with diffuse scattering surfaces in optical media. Experimental data are in good agreement with the results of numerical simulations and are consistent with theoretical notions. It is shown that the proposed method can be implemented on a simple technical basis and used is practice. 相似文献
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移动互联网业务发展和智能终端的普及对客户感知监测和网络优化提出了全新挑战,本文提出了一种可用于2G/3G及LTE智能终端的客户感知监测方法及系统架构,论述了在商用终端上实现业务异常自动发现、智能诊断与实时上报的流程和方法,并结合TD-SCDMA网络维护和优化工作实际介绍了此系统的应用成效及其在推动TD-SCDMA终端产业成熟过程中所做出的贡献. 相似文献
74.
ROBERTA T.P. CORREIA PATRICK MCCUE MARGARIDA M.A. MAGALHÃES GORETE R. MACÊDO KALIDAS SHETTY 《Journal of Food Biochemistry》2004,28(5):404-418
In this paper, we investigated the potential for Rhizopus oligosporus to produce enhanced levels of free phenolics from guava residue mixed with soy flour as the nitrogen source.β‐glucosidase activity and antioxidant activity in crude extracts were evaluated. Two substrates were studied based on carbon and nitrogen ratios: A, 90% guava residue : 10% soy flour (G9) and B, 50% guava residue : 50% soy flour (G5). Bioprocessing increased water extractable phenolics 12.9% with G9 substrate and 98.6% with G5 substrate. For both substrates, antioxidant activity increased during early stages of fungal growth but decreased thereafter. Phenolic antioxidant mobilization during bioprocessing was associated withβ‐glucosidase activity and hypothesized to involve the mobilization of polymeric phenolics. The bioconversion of soy flour‐supplemented guava residue by R. oligosporus represents a novel strategy for the enhancement of phenolic antioxidant content and potential commercial value of guava wastes. 相似文献
75.
PENNY M. AMATO DONALD DO HAMANN HERSHELL R. BALL JR. E. ALLEN FOEGEDING 《Journal of food science》1989,54(5):1136-1140
The effects of poultry species (chicken and turkey), muscle groups (breast, thigh, and drum) and NaCl concentration (1% and 2%) on a low fat gel system were compared using measurements of shear stress (strength), shear strain (deformability), and two water retention measurements. Results showed doubling NaCl tended to double stress for all species and muscle groups and increased strain by 30–50%. Cross species differences showed higher stress in turkey gels than in chicken gels with 2% NaCl. For both species, stress, strain and water retention were lowest in breast gels with both NaCl concentrations, and strain was greater in thigh gels than in drum gels with 2% NaCl. 相似文献
76.
DAL-HYUN DO ALEXEI GRIGORIEV DONG MIN KIM CHANG-BEOM EOM PAUL G. EVANS ERIC M. DUFRESNE 《Integrated ferroelectrics》2013,141(1):174-181
ABSTRACT Probing the piezoelectricity and ferroelectricity of thin film devices and nanostructures quantitatively has proven to be challenging because the appropriate experimental tools have had a limited range of usefulness. We show here that the piezoelectric and ferroelectric properties of epitaxial thin films can be measured quantitatively using time-resolved synchrotron x-ray microdiffraction. Microdiffraction combines structural specificity with the appropriate spatial resolution and ability to probe structures with electrical contacts. Our measurements of piezoelectric coefficients and coercive electric fields for Pb(Zr,Ti)O3 capacitors using this approach are in excellent quantitative agreement with results obtained electrically and mechanically. The time and spatial resolution of microdiffraction probes are well-defined and decoupled from electrical and mechanical resonances of the ferroelectric capacitor. 相似文献
77.
SR Johnston DO Constenla J Moore H Atkinson RP A'Hern G Dadian PG Riches ME Gore 《Canadian Metallurgical Quarterly》1998,77(8):1280-1286
The purpose of this study was to evaluate in a randomized phase II trial the efficacy and toxicity of combination biochemotherapy compared with chemotherapy alone in patients with metastatic melanoma. Sixty-five patients with metastatic melanoma (ECOG performance status 0 or 1) were randomized to receive intravenous BCNU 100 mg m(-2) (day 1, alternate courses), cisplatin 25 mg m(-2) (days 1-3), DTIC 220 mg m(-2) (days 1-3) and oral tamoxifen 40 mg (BCDT regimen) with (n = 35) or without (n = 30) subcutaneous interleukin 2 (IL-2) 18 x 10(6) iu t.d.s. (day - 2), 9 x 10(6) iu b.d. (day - 1 and 0) and interferon 2 alpha (IFN-alpha) 9 MU (days 1-3). Evidence for immune activation was determined by flow cytometric analysis of peripheral blood lymphocytes. Treatment was repeated every 4 weeks up to six courses depending on response. The overall response rate of BCDT with IL-2/IFN-alpha was 23% [95% confidence interval (CI) 10-40%] with one complete response (CR) and seven partial responses (PR), and for BCDT alone 27% (95% CI 12-46%) with eight PRs; the median durations of response were 2.8 months and 2.5 months respectively. Sites of response were similar in both groups. There was no difference between the two groups in progression-free survival or overall survival (median survival 5 months for BCDT with IL-2/IFNalpha and 5.5 months for BCDT alone). Although 3 days of subcutaneous IL-2 resulted in significant lymphopenia, evidence of immune activation was indicated by a significant rise in the percentage of CD56- (NK cells) and CD3/HLA-DR-positive (activated T cells) subsets, without any change in the percentage of CD4 or CD4 T-cell subsets. Toxicity assessment revealed a significantly higher incidence of severe thrombocytopenia in patients treated with combination chemotherapy than with chemotherapy alone (37% vs 13%, P = 0.03) and a higher incidence of grade 3/4 flu-like symptoms (20% vs 10%) and fatigue (26% vs 13%). The addition of subcutaneous IL-2 and IFNalpha to BCDT chemotherapy in a randomized phase II trial resulted in immune activation but did not improve response rates in patients with metastatic melanoma, and indeed may increase some treatment-related toxicity. 相似文献
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LD Ormerod JA Larkin CA Margo PR Pavan MM Menosky DO Haight JP Nadler BG Yangco SM Friedman R Schwartz JT Sinnott 《Canadian Metallurgical Quarterly》1998,26(1):34-45; discussion 46-7
Eleven patients with rapidly progressive herpetic retinal necrosis (RPHRN) complicating AIDS were investigated retrospectively to study the disease spectrum, systemic involvement, and therapy. The mean CD4 cell count was 24/microL. There was a characteristic disease pattern with rapid progression, 82% bilaterality, relative resistance to intravenous antiviral therapy, and 70% retinal detachment. Varicella-zoster virus was the probable cause in 10 patients (detected by polymerase chain reaction in two eyes investigated), and herpes simplex virus was the probable cause in one. Cutaneous zoster occurred previously in 73% but was not concurrent. Seventy-three percent had central nervous system disease, possibly virus-related. RPHRN may be a local herpetic recrudescence in an immune-privileged site with transneural spread. Only four of 20 affected eyes retained useful vision. Poor ocular bioavailability, retinal ischemia, acquired drug resistance, and strain pathogenicity may underlie treatment failure. Acyclovir therapy appears relatively ineffective. Combined intravenous and intravitreal therapy with foscarnet and ganciclovir may be the best current management. Research advances are needed urgently. 相似文献