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排序方式: 共有1345条查询结果,搜索用时 15 毫秒
71.
M Tomohiro Y Aida M Inomata Y Ito A Mizuno S Sakuma 《Canadian Metallurgical Quarterly》1997,41(3):121-129
The purpose of this study is to examine if microencapsulated PC12 cells may provide long term effects to the hemiparkinsonian rats. A modified technique was used to encapsulate PC12 cells into gelled microspheres. We found that the PC12 cells can survive in the modified microcapsules in vitro. Most of the PC12 cells formed cluster 3 weeks after incubation. The PC12 cell-loaded microcapsules were also examined in vitro. Adult Sprague-Dawley rats, anesthetized with chloral hydrate, were injected unilaterally with 6-hydroxydopamine into the medial forebrain bundle. The effectiveness of this lesion was tested by measuring apomorphine or methamphetamine-induced rotation one month after lesioning. The unilaterally lesioned rats were transplanted with microencapsulated PC12 cells. Results showed that apomorphine and methamphetamine-induced rotations were greatly suppressed after transplantation. One year after the grafting, the animals were anesthetized with urethane for the voltammetric study. Low dose of KCl was directly injected into the grafted striatum through pressure microejection. We found that KCl-induced DA release, as measured by voltammetric techniques, was regenerated in the striatum. The animals were later sacrificed for histological examination. We found that capsules were present in the lesioned striatum one year after grafting. Most of the capsules contained no PC12 cell. However, some capsules were filled entirely with PC12 cells. Taken together, our data suggested that PC12 cells can survive in the capsule in vitro and may provide long-term dopaminergic effects to the hemiparkinsonian rats. 相似文献
72.
We investigated the effects of YM294, recombinant human interleukin-11, on changes in blood cell levels in carboplatin-treated rats. Continuous infusion of YM294 was carried out by either intravenous or subcutaneous injection (10 and 100 micrograms/rat/day) for 14 days via an implanted osmotic pump. Carboplatin (30 mg/kg iv) significantly decreased platelet counts on days 7-9; counts subsequently increased to levels greater than the initial level by day 21. Intravenous administration of YM294 inhibited this decrease in platelet count by carboplatin and increased the platelet count in the recovery phase in a dose-dependent manner. YM294 also showed effects on carboplatin-induced changes in white blood cell and red blood cell counts; these effects seemed, however, to be neither consistent nor dose-dependent. The effects of YM294 on subcutaneous infusion were similar to those on intravenous infusion. The effect of YM294 on the survival of rats treated with a higher dose of carboplatin (60 mg/kg iv) was also investigated. YM294 (100 micrograms/rat/day) given by continuous intravenous infusion increased the 30-day survival rate. These results confirm the utility of YM294 in the treatment of thrombocytopenia after chemotherapy. 相似文献
73.
The purpose of this study is to develop an approach for unified constitutive modeling based on experimentally determined back stress and overstress. Back stress and overstress were experimentally determined for Type 316 stainless steel at 600°C, by analyzing the unloading curve for the stress-strain response of cyclic strain tests. The result has indicated that the cyclic strain hardening behavior is mainly caused by hardening in the back stress. A phenomenological unified constitutive model in which the back stress and drag stress are taken as the internal state variables is proposed, and has been shown that this model is able to simulate the cyclic inelastic behavior. 相似文献
74.
N Keicho K Tokunaga K Nakata Y Taguchi A Azuma M Bannai M Emi N Ohishi Y Yazaki S Kudoh 《Canadian Metallurgical Quarterly》1998,158(3):846-850
Diffuse panbronchiolitis (DPB) in East Asia is a distinctive chronic obstructive pulmonary disease of unknown etiology. We hypothesize that the disease susceptibility is due to genetic predisposition unique to Asians. Association between human leukocyte antigen (HLA)-Bw54 and the disease was previously reported. In the present study, using newly developed polymerase chain reaction (PCR)- based methods, we directly analyzed HLA class I and II alleles in 76 Japanese patients. HLA-A, -B, and -C antigens were screened by the conventional typing method, and then B22-group alleles including HLA-B54 were genotyped by single-strand conformation polymorphism analysis. Alleles of HLA-DRB1 gene were fully determined by the microtiter plate hybridization method. Thirty-seven percent of the patients possessed HLA-B*5401 allele conserved predominantly in East Asians, as compared with 15% of 110 healthy volunteers (chi2 = 12.4, p = 0.0004). In addition, 4% of the patients possessed B*5504 also unique to Asians but a rare allele which was not found in normal control subjects in this study. Typing of HLA-DRB1 class II gene did not demonstrate strong positive association with the disease. A33, B44, and DRB1*1302 showed negative association with the disease. We conclude that distinctive molecular structure of HLA-B alleles or a closely linked gene in the HLA region contributes to genetic predisposition in diffuse panbronchiolitis. This may partly explain why this disorder is found primarily in Asians. 相似文献
75.
R Hirose S Suita T Taguchi T Koyanagi H Nakano 《Canadian Metallurgical Quarterly》1995,30(9):1390-1393
An infant girl with extralobar pulmonary sequestration (PS) composed of congenital cystic adenomatoid malformation (CCAM)-like structure is presented. Initially, the antenatal sonographic findings indicated CCAM. The macroscopic findings of the resected specimen were compatible with extralobar PS; however, the microscopic findings showed cystic structure mimicking type II CCAM. The combination of PS and CCAM is rare, and it is likely that the embryological origin is common to both. There is confusion in the classification of these two congenital anomalies. In this report, the histological and sonographic findings of PS and CCAM are discussed. 相似文献
76.
T Taguchi S Tsukagoshi H Furue H Niitani K Noda 《Canadian Metallurgical Quarterly》1998,25(12):1899-1907
Oxaliplatin is a new platinum derivative. A multicentric phase I study was conducted with a monotherapy of Oxaliplatin. A total of 20 patients were enrolled who had histologically proven 6 ovarian cancers, 5 uterine cervix cancers, 3 lung cancers, 3 breast cancers, 1 endometrial cancer, 1 gastric cancer, and 1 colorectal cancer. Oxaliplatin was administered as a 2-hour infusion at doses of 20, 40, 80, 130, and 180 mg/m2 every 3 weeks, for a total of 30 cycles. A dose-related and reversible peripheral sensory neuropathy was the dose-limiting toxicity with minimal hematotoxicity and no nephrotoxicity. No hydration was needed. The plasma platinum concentration was biphasically decreased. Cmax and AUC were dose-dependent. T1/2 beta was 31.3 hours. The recommended dose for further studies was 130 mg/m2. A partial response was observed in endometrial cancer. 相似文献
77.
Summary Series of several alkylated cycloheptanes were detected in some commercial samples of high pressure polyethylene. The structures of the alkylated cycloheptanes were found closely related to the chain transfer agents used in the polymerization process. A probable mechanism involving radical cyclization to cycloheptane structures was presented. 相似文献
78.
In the past decade it has been suggested that the isotopic enrichment of 28-silicon enhances its thermal properties. Thus, 28-silicon is suitable as a heat sink in large-scale integrated circuits. Although some studies have focused on the measurement of isotopically enriched silicon's thermal properties, accurate experimental data are not sufficient because of this material's high conductivity and large heat capacity which make measurement difficult. However, the dynamic grating radiometry (DGR) method has been successfully developed to measure the thermal diffusivity of 28-silicon. In the DGR method, the sample is heated by interference of two pulsed laser beams, and the temperature decay is monitored by an infrared detector. By analyzing the temperature changes of the peaks and valleys of the thermal grating, the thermal diffusivities parallel and perpendicular to the sample surface are obtained simultaneously. In this paper, the optimum conditions of the experimental setup for measuring isotopically enriched silicon are discussed. The comparison of thermal diffusivities between 28-silicon and natural silicon (with a thickness of about 100m) is presented, and the applicability of DGR to isotope engineering is reported. 相似文献
79.
80.
Koichiro Koyama Masao Morishita Tomohiro Harada Nobuyuki Maekawa 《Metallurgical and Materials Transactions B》2003,34(5):653-659
The standard Gibbs energies of formation of Fe2Mo3O12, Fe2Mo3O8, FeMoO4, and Fe2MoO4 of the Fe-Mo-O ternary system and the μ phase of the Fe-Mo binary system have been determined by measuring electromotive forces of galvanic cells having an Y2O3-stabilized ZrO2 solid electrolyte. The results are as follows: $$\begin{gathered} \Delta _f G^\circ (FeMoO_4 )/kJ \cdot mol^{ - 1} = - 1053.5 + 0.2983(T/K) \pm 0.4 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_8 )/kJ \cdot mol^{ - 1} = - 2347 + 0.6814(T/K) \pm 1 \hfill \\ Temperature range: 1112 to 1339 K \hfill \\ \Delta _f G^\circ (Fe_2 Mo_3 O_{12} )/kJ \cdot mol^{ - 1} = - 2993 + 0.9105(T/K) \pm 2 \hfill \\ Temperature range: 1040 to 1145 K \hfill \\ \Delta _f G^\circ (Fe_{0.58} Mo_{0.42} )/kJ \cdot mol^{ - 1} = - 18.7 + 0.0117(T/K) \pm 0.1 \hfill \\ Temperature range: 1162 to 1223 K \hfill \\ \Delta _f G^\circ (Fe_2 MoO_4 )/kJ \cdot mol^{ - 1} = - 1174 + 0.342(T/K) \pm 1 \hfill \\ Temperature range: 1243 to 1466 K \hfill \\ \end{gathered} $$ where the standard pressure is 1 bar (100 kPa). 相似文献