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931.
Y Oshiro N Fuijita H Tanaka N Hirabuki H Nakamura I Yoshiya 《Canadian Metallurgical Quarterly》1998,9(10):2285-2289
Activation in numerous regions of the brain is likely to be involved in the complex neural network function of pain perception. To detect the cortical representation during nonpainful and painful stimuli, which were presented using electrical finger stimulation in six normal right-handed male volunteers, we performed echo-planar functional magnetic resonance imaging (fMRI). Using a 1.5-T MR system that scanned the supratentorial region of the brain, we obtained multislice BOLD-based functional MR images with single-shot gradient-echo echo-planar imaging (EPI). The data show that dispersed brain regions are activated during painful stimulation, and especially demonstrate the significance of the SII-insular region in pain perception. 相似文献
932.
BACKGROUND: To evaluate the antitumor activity in patients with T3b, T4 or metastatic urothelial carcinoma treated with MEC or M-VAC chemotherapy, by performing a multi-center randomized prospective study. METHODS: From 1991 to 1995, 89 patients with T3b, T4 or metastatic urothelial carcinoma were randomly allocated to a methotrexate, epirubicin and cisplatin chemotherapy group (arm 1: S-MEC therapy; n = 29), a dose-intensified MEC therapy combined with G-CSF group (arm 2: I-MEC therapy; n = 30) or a methotrexate, vinblastine, doxorubicin and cisplatin chemotherapy (arm 3: M-VAC therapy; n = 30). At the registration center, the patients were stratified into previously untreated patients and patients with recurrence after radical operation and then randomly allocated to the treatment groups. In each arm, two or more courses of chemotherapy (4-week cycles) were performed. RESULTS: Of the 88 eligible patients, four treated with S-MEC therapy and two treated with I-MEC therapy showed CR. The response rates (CR + PR) were 52% (15/29) with S-MEC therapy, 76% (22/29) with I-MEC therapy and 47% (14/30) with M-VAC therapy. The response rate with I-MEC therapy was significantly higher than that with M-VAC therapy (P = 0.02). Although the incidence of leukopenia was low with I-MEC therapy, the incidence of thrombocytopenia was high with this therapy. CONCLUSION: MEC therapy used in this study is promising in terms of the antitumor effects. 相似文献
933.
H Tada Y Irie A Yagoro H Ohya S Hayashi R Fushimi H Tamaki N Amino 《Canadian Metallurgical Quarterly》1994,6(3):93-97
We measured serum concentrations of apolipoproteins (apo A-I, A-II, B, C-II, C-III and E) in patients with thyroid disease (hyperthyroidism; n = 44, hypothyroidism; n = 15) and in normal subjects (n = 89). We found that apoA-II, B and C-III concentrations revealed significant difference among three groups of the normal (apoA-II; 31.4 +/- 4.9 mg/dl, apoB; 85.8 +/- 16.3 mg/dl, apoCIII; 7.45 +/- 2.99 mg/dl), hyperthyroidism (apoA-II; 29.8 +/- 5.4, apoB; 63.4 +/- 18.9, apoC-III; 6.28 +/- 2.45) and hypothyroidism (apoA-II; 27.5 +/- 5.3, apoB; 108.0 +/- 30.9, apoC-III; 9.43 +/- 2.74). Thyroid hormones showed clear negative correlation to apoB (r = 0.70, p < 0.001). Furthermore, apoC-III was also found to be negatively correlated with thyroid hormone concentrations (r = 0.47, p < 0.001). 相似文献
934.
K Takada Y Matsumura S Dohmen N Mitsutomi M Takaoka S Morimoto 《Canadian Metallurgical Quarterly》1996,59(9):PL111-PL116
The profile of endothelin-1 (ET-1) release from cultured vascular endothelial cells (ECs) obtained from deoxycorticosterone acetate (DOCA)-salt hypertensive rats, was examined and compared with that from normotensive sham rats. ET-1 release from ECs was increased in a time-dependent manner, and the level of DOCA-salt hypertensive rats was higher than that of sham rats. Incubation of ECs with transforming growth factor (TGF)-beta 1 or thrombin resulted in a significant increase in the ET-1 release, while FK409, a novel nitric oxide donor, produced a dose-dependent decrease in the release. In the case of ECs from DOCA-salt hypertensive rats, the potencies of TGF-beta 1- or thrombin-induced action was much less than that seen with sham rats, while the difference of reactivity to FK409 was not observed between ECs of DOCA-salt rats and sham rats. Thus, ET-1 production in ECs appears to be up-regulated in DOCA-salt hypertensive rats. In addition, there seems to be an abnormalities in the signaling pathway via TGF-beta 1- or thrombin-induced enhancement of ET-1 production in ECs of DOCA-salt hypertensive rats. 相似文献
935.
Acid Urease: Reduction of Ethyl Carbamate Formation in Sherry under Simulated Baking Conditions 总被引:1,自引:0,他引:1
Acid urease derived from Lactobacillus fermentum was applied to reduce ethyl cthe target level (90 μg/L). However, complete prearbamate (EC) formation in California sherry production. Commercial sherry and sherry base were treated with urease under different conditions. Amounts of urea were determined and EC amounts were monitored by gas chromatography. Urea removal by acid urease reduced EC formation during the baking process and effectively maintained EC concentrations below vention of EC was not achieved because of precursors other than urea. 相似文献
936.
MB Melo FF Costa ST Saad I Lorand-Metze S Bordin NN Ahmad 《Canadian Metallurgical Quarterly》1998,22(9):787-792
Patient 1: A 48-year-old man was admitted to Osaka Red Cross Hospital because of fever and dyspnea. Laboratory examination revealed pancytopenia, liver dysfunction and hematostatic abnormality. Chest radiographs obtained on admission revealed ground-glass opacity in both lung fields, and an analysis of arterial blood showed severe hypoxemia (PaO2:46.8 Torr). Pulse therapy with methylprednisolone was started. Although the hypoxemia subsided and radiographic findings rapidly improved, pancytopenia persisted. Examination of bone marrow aspirate revealed mature histiocytes with marked hemophagocytosis. Amplified Mycobacterium tuberculosis direct tests of bronchoalveolar lavage fluid, sputum, urine, and bone marrow were all positive, and Mycobacterium tuberculosis was cultured from sputum and urine. Although the patient was taking antituberculous agents, his pancytopenia persosted. Treatment with etoposide induced remssion. Patient 2: A 19-year-old woman was admitted to Osaka Red Cross Hospital because of prolonged cough and fever. Laboratory examination revealed leukocytosis, liver dysfunction, and hematostatic abnormality. Serologic tests provided conclusive evidence of Mycoplasma infection and a CRP test was strongly positive. Chest radiographs obtained on admission revealed infiltration shadows in the middle and lower lung fields on both sides, with left pleural effusion. An analysis of arterial blood showed hypoxemia (PaO2: 54.2 Torr). Examination of bone marrow and pleural effusion samples revealed mature histiocytes with marked hemophagocytosis. Although treatment with antibiotics and pulse therapy with methylprednisolone was started, the patients respiratory functions deteriorated. Endotracheal intubation was performed. Therapy with etoposide induced remission. Hemophagocytic syndrome associated with Mycoplasma infection and tuberculosis appears to be exceedingly rare. In these 2 cases, it was difficult to achieve remission with therapy for the underlying infections, but etoposide treatment was effective. 相似文献
937.
Film-type electrodes of hydrogen absorbing intermetallic compound and alloys, LaNi5, Ni0.11 Ti0.89, Ni0.50 Ti0.50 and Ni0.76 Ti0.24 were prepared by a flash evaporation method. The hydrogen electrode reaction characteristics of the LaNi5 and NiTi alloy films in 1 M NaOH are very similar to each other. The reaction proceeds via the Volmer-Tafel reaction route with mixed rate-determining characteristics. The exchange current densities of the constituent steps, as well as the overall reaction, are in the range of 10?6 A cm?2 (true). Surface analysis by an XPS technique has shown that La or Ti on the electrode surface exists as an electrocatalytically innert oxide of La2O3 or TiO2. Close similarities of these electrodes with pure Ni electrodes indicate that Ni is responsible for the electrocatalytic activity. No synergistic effect is thus noticeable. 相似文献
938.
A new material supposed to have a mixed structure of polyacenic skeletons has been prepared from phenol-formaldehyde resin through the pyrolytic process. This material is air-stable, showing a wide variation of electrical conductivity with pyrolytic temperature. Moreover, it has been confirmed that the present material can be doped with an electron acceptor (iodine) and an electron donor (sodium) in a successful manner, giving rise to a maximum increase in the conductivity of more than seven and eleven orders of magnitude, respectively. The results of the electron probe X-ray microanalysis (EPMA) with respect to the doped samples have shown a uniform distribution of the dopants inside these materials. 相似文献
939.
940.
Sherif M.H. Rashed 《Computers & Structures》1984,18(2):277-293
An efficient method of analysis of non-linear behavior until collapse of large size redundant structures is presented. The method is named as The “Idealized Structural Unit Method”. In this method the structure is divided into the biggest possible “Structural Units” whose geometric and material nonlinear behavior can be idealized and described in a concise analytical-numerical form. The structure is reassembled and load is applied incrementally until ultimate strength is attained.In this method, modeling is an obvious operation of dividing the structure into its actual structural units. This eliminates the effort required for the choice of type of element or size of mesh as in the finite element method. The number of structural units and overall degrees of freedom required for the analysis of a structure by this method are less in order than the number of elements and overall degrees of freedom required to analyze the same structure by the FEM. Costs of computer and data preparation may be drastically reduced.Application of the method to metal structures built up of deep I girders, such as bridge girders, ships deep girders and grillage structures is considered. The “Girder Structural Unit” is defined and its behavior under increasing loads is idealized based on existing as well as newly developed theoretical and experimental studies. Conditions for web bucking, ultimate strength and full plastic strength are established and expressions for stiffness during various stages are derived. A deep girder structure may then be treated as an assembly of such “Girder Structural Units”. Results of analysis of example structures are presented. The consumed computer time is found to be very short, as expected. Comparisons with results of experimental studies show good agreement. 相似文献