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61.
62.
Y. Yoshida S. Tokashiki K. Kubota R. Shiratuchi Y. Yamaguchi M. Kono S. Hayase 《Solar Energy Materials & Solar Cells》2008,92(6):646-650
In order to improve the physical and chemical contacts between a porous TiO2 layer and an F-doped SnO2 transparent conductive layer (FTO), the surface of the FTO layer is polished. After polishing, the surface roughness decreased. However, light transmittance and sheet resistance did not vary largely. The short circuit current (Jsc) and efficiencies increased after the FTO was polished. It was found that the interfacial charge transfer between a TiO2 layer and an FTO layer decreased by impedance measurement, which suggests that contacts between an FTO and a TiO2 layer are improved because of the flatted surfaces or removal of electrical impurities. We propose one of the industrially important phenomena that surface polishing of FTO is one of the ways to increase photovoltaic performances for DSCs. 相似文献
63.
In order to clarify the contribution to carrier density by oxygen vacancies in tin-doped indium oxide (ITO) films prepared on glass substrates by the hot-cathode plasma sputtering method, we have investigated the effect of annealing on the electrical properties of an ITO film with a resistivity of 1.0 × 10− 4 Ω cm. A drastic decrease in carrier density from 2.0 × 1021 to 0.88 × 1021 cm− 3 was found with gradual increase in the Hall mobility from 29 to 35 cm2 V− 1 s− 1 for repeated annealing cycles, when the ITO film was exposed for one hour to 400 °C oxygen gas at atmospheric pressure. The results indicate that the contribution of oxygen vacancies to carrier density was ca. 1.12 × 1021 cm− 3 for the ITO film with an overall carrier density of 2.0 × 1021 cm− 3. 相似文献
64.
65.
D Lo C Reilly LA Marconi L Ogata Q Wei G Prud'homme D Kono L Burkly 《Canadian Metallurgical Quarterly》1995,13(2):147-160
While the thymus may be effective in inducing tolerance to lymphoid associated antigens, it is not as efficient in deleting T cells reactive to peripheral tissue specific antigens. Therefore, to maintain self tolerance to peripheral tissues, post-thymic mechanisms must be invoked. One important way to prevent autoimmune pathology mediated by autoreactive CD4 T cells is the diversion of clones to regulatory Th2 effector cells. However, many different factors contribute in vivo to the decision of stimulated CD4 T cells to develop into Th1 versus Th2 cells. For example, T cell signaling pathways may influence the types of cytokines produced by naive T cells, and studies have provided evidence for a genetic polymorphism among common mouse strains that can significantly influence the early cytokine production in stimulated naive CD4 T cells. The allele carried by the BALB/c strain promotes IL-4 production, and consequently provides resistance to autoimmune diabetes in our transgenic mouse model. In addition, antigen presenting cells can influence the development of stimulated CD4 T cells in part through the production of cytokines such as IL-12. The absorption of IL-12 in vivo can permit the expansion of Th2 type effector cells, and this phenomenon will also protect mice from autoimmunity. Finally, the relative potency of various class II positive antigen presenting cell types can influence the development of autoreactive T cells, with dendritic cells apparently being the strongest stimulator of Th1 responses. Consistent with this notion, a relB knockout mouse, which is missing dendritic cells, appears to drive Th2 development even in response to viral infection. In sum, these various influences over the Th1/Th2 decision in vivo may provide new targets for immunotherapy of autoimmune diseases. 相似文献
66.
67.
JD Nieland K Loviscek K Kono KS Albain AR McCall RK Potkul SG Fisher MP Velders M Petersson R Kiessling WM Kast 《Canadian Metallurgical Quarterly》1998,21(4):317-322
BACKGROUND AND OBJECTIVE: The use of hematopoietic growth factors in association with chemotherapy in human immunodeficiency virus (HIV)-related non-Hodgkin's lymphoma (NHL) has been recommended, but few studies have evaluated its cost-effectiveness. DESIGN AND METHODS: The effects of recombinant granulocyte colony-stimulating factor (G-CSF) were analyzed in 33 consecutive patients with HIV-related NHL treated at a single institution with the same chemotherapy program, ProMACE-CytaBOM, with G-CSF, in 21 cases diagnosed after December 31, 1991, or without G-CSF, in 12 cases diagnosed earlier. Pearson's chi-square analysis and the two-sided Student's t-test were used for statistical comparisons. The method of Kaplan-Meyer and the log-rank-test were used for survival analyses. RESULTS: G-CSF support significantly reduced the frequency of day-1 drug dose reductions (p < 0.001) and of chemotherapy delays (p < 0.001), and improved the actual delivered doses of adriamycin, cyclophosphamide and etoposide (p < 0.02). In patients with a CD4+ count < 0.01 x 10(9)/L, chemotherapy could be given at full doses in 90% of cycles with G-CSF compared to only 20% without it. G-CSF affected neither the frequency and duration of fever and hospitalization nor the complete remission and survival rates after stratification according to the CD4+ count. INTERPRETATION AND CONCLUSIONS: G-CSF support significantly improved dose-intensity in patients with HIV-related NHL treated with aggressive chemotherapy, particularly in the subgroup with a CD4+ count < 0.1 x 10(9)/L, but it did not improve their clinical outcome. 相似文献
68.
To evaluate therapeutic effect in terms of necrosis or cavity, enhanced MRI was performed in 40 lung cancer patients treated by conservative therapy. We provided the reduction ratio of the viable tumor as calculated by a volume method and a cross-sectional method. In the volume method, the volume of necrosis was subtracted from the volume of the tumor, and in the cross-sectional method, the product of the longest diameter and widest perpendicular diameter of necrosis was subtracted from the product of the longest diameter and widest perpendicular diameter of the tumor. We then examined whether we could substitute the cross-sectional method for the volume method. The reduction ratios of viable tumor calculated by the two methods were in good correlation. The limits of agreement of each method and their repeatability coefficients were considered small enough for clinical use. Therefore, we concluded that the cross-sectional method could be used in place of the volume method for clinical purposes. In evaluating therapeutic effect in terms of necrosis when using contrast-enhanced MR imaging, the reduction ratio of the viable tumor determined by the cross-sectional method can be substituted for that determined by the volume method. 相似文献
69.
1. The release of endogenous gamma-aminobutyric acid (GABA) and glutamic acid in the human brain has been investigated in synaptosomal preparations from fresh neocortical samples obtained from patients undergoing neurosurgery to reach deeply located tumours. 2. The basal outflows of GABA and glutamate from superfused synaptosomes were largely increased during depolarization with 15 mM KCl. The K(+)-evoked overflows of both amino acids were almost totally dependent on the presence of Ca(2+) in the superfusion medium. 3. The GABAB receptor agonist (-)-baclofen (1, 3 or 10 microM) inhibited the overflows of GABA and glutamate in a concentration-dependent manner. The inhibition caused by 10 microM of the agonist ranged from 45-50%. 5. The effect of three selective GABAB receptor antagonists on the inhibition of the K(+)-evoked GABA and glutamate overflows elicited by 10 microM (-)-baclofen was investigated. Phaclofen antagonized (by about 50% at 100 microM; almost totally at 300 microM) the effect of (-)-baclofen on GABA overflow but did not modify the inhibition of glutamate release. The effect of (-)-baclofen on the K(+)-evoked GABA overflow was unaffected by 3-amino-propyl (diethoxymethyl)phosphinic acid (CGP 35348; 10 or 100 microM); however, CGP 35348 (10 or 100 microM) antagonized (-)-baclofen (complete blockade at 100 microM) at the heteroreceptors on glutamatergic terminals. Finally, [3-[[(3,4-dichlorophenyl) methyl]amino]propyl] (diethoxymethyl) phosphinic aid (CGP 52432), 1 microM, blocked the GABAB autoreceptor, but was ineffective at the heteroreceptors. The selectivity of CGP 52423 was lost at 30 microM, as the compound, at this concentration, inhibited completely the (-)-baclofen effect on both GABA and glutamate release. 5. It is concluded that GABA and glutamate release evoked by depolarization of human neocortex nerve terminals can be affected differentially through pharmacologically distinct GABAB receptors. 相似文献
70.
M Murakami Y Kuroda Y Okamoto K Kono E Yoden F Kusumi K Hajiro S Matsusue H Takeda 《Canadian Metallurgical Quarterly》1998,40(5):1049-1059
PURPOSE: A prospective clinical trial was undertaken to investigate the feasibility of concurrent chemoradiotherapy for esophageal carcinomas. MATERIALS AND METHODS: Between June 1989 and May 1996, forty patients with operable squamous cell carcinoma of the thoracic esophagus (Stage 0 to III: UICC 1987), ages 45 to 78 years (mean: 64), were enrolled in a study of neoadjuvant concurrent chemoradiotherapy followed by definitive high-dose radiotherapy (CRT group) or surgery (CRT-S group). Neoadjuvant chemoradiotherapy consisted of 44 Gy in 40 fractions for 4 weeks (2.2 Gy/2 Fr/day) through 10-MVX rays, with 2 courses of cisplatin (80-100 mg/body, mean: 60 mg/m2, Day 1, bolus injection) and 5-fluorouracil (500-1000 mg/body/day, mean: 400 mg/m2, Days 1-4, continuous infusion). After completion of neoadjuvant chemoradiotherapy, an intermediate clinical response was assessed by barium swallow, esophagoscopy with/without biopsy, EUS in most cases, thoracic and upper abdominal CT scan, and cervical US. Definitive chemoradiotherapy was performed in patients when regression of more than 75% was evident (CRT Group), and esophageal resection was indicated in those who remained at less than 75% (CRT-S Group). In CRT Group, a cumulative dose of 60-70 Gy for Tis, T1 and 65-75 Gy for T2-T4 tumor with high-dose-rate intraluminal brachytherapy and a total of 3 courses of chemotherapy were planned. In CRT-S Group, intraoperative radiotherapy for abdominal lymphatic system and postoperative supraclavicular irradiation were added. RESULTS: At the time of intermediate assessment, complete response (CR) was observed in 16 patients, a partial response (PR) in 22, and no change (NC) in 2. Thirty responding patients (CR, 16; PR, 14) entered the CRT Group, and 10 nonresponding patients (PR, 8; NC, 2) were followed by surgery (CRT-S Group). Radiotherapy was completed satisfactorily, but chemotherapy was suspended in 26 patients (65%) because of acute toxicity. Clinical CR rate at the completion of treatment showed 90% in CRT Group, and pathologic CR rate 10% in CRT-S Group. The overall median survival was 45 months, survival at 1, 2, and 3 years being 100%, 72%, and 56%, respectively. Local-regional failure was observed in 7 patients (all in CRT Group), distant failure in 6 (3 in CRT Group, 3 in CRT-S Group) and local-regional with distant failure in 1 (CRT Group). Four patients with local-regional recurrence in the CRT Group were salvaged by surgery. Overall survival at 2 and 3 years for CRT vs. CRT-S Group was 72%, 64% vs. 75%, 38%, respectively. No treatment-related mortality was observed. The rate of the 'esophagus conservation' was 65% (Stage 0: 1 of 1, 100%; Stage I: 11 of 12, 92%; Stage II: 8 of 17, 47%; Stage III: 6 of 10, 60%). CONCLUSION: Our results demonstrated that almost all early disease (Stage 0-I) and about half of advanced disease (Stage II-III) could be conserved, their esophagus treated by the multidisciplinary approach centering on high-dose radiotherapy and concurrent chemotherapy. 相似文献