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101.
The effects of the magnetic flux density of the Ag sputter target surface on plasma parameters were investigated using the Langmuir probe system in this work. It was found that the electron energy and electron density near the substrate clearly decreased at a high magnetic flux density. In addition, the difference between plasma potential and floating potential (VpVf) decreased at the high magnetic flux density relative to the potentials at the low magnetic flux density. The changes in plasma parameters could be interpreted as the result of many electrons being trapped in the neighborhood of the target surface (cathode sheath) at the high magnetic flux density; hence, the number of electrons in the space near the substrate is reduced. The Ag thin films exhibited low resistivity at a high magnetic flux density. The reduction in resistivity was attributed to the following factors: the low electron energy and electron density near the substrate; the low kinetic energy of positive argon ions; the low kinetic energy of argon atoms backscattered onto the target surface.  相似文献   
102.
Sequential MTX/5-FU therapy (intravenous route) is powerful chemotherapy especially for poorly differentiated adenocarcinoma of the stomach and its peritoneal metastases. The authors had proposed the idea of intraperitoneal sequential MTX/5-FU chemotherapy for potential peritoneal metastases and micrometastases from advanced gastric carcinoma. This experimental study was planned to confirm this experimentally. Peritoneal seeding model of nude mice was made by the intraperitoneal inoculation of human gastric cancer cell line MKN-45. Control group (n = 5) had no treatment. The intraperitoneal (i.p.) group and intravenous (i.v.) group underwent the treatments on the 7th, 14th, and 21st day after cell implantation. Experimental chemotherapies consisted of intraperitoneal injection of MTX (15 mg/kg, 1.5 ml saline) and 5-FU (50 mg/kg, 1.0 ml saline) for i.p. group and intravenous injection of MTX (15 mg/kg, 0.2 ml saline) and 5-FU (50 mg/kg, 0.2 ml saline) for i.v. group. Interval time between MTX and 5-FU administration was 2 hours. On the 35th day after the cell implantation necropsies were performed. Counting of peritoneal metastatic nodules revealed the number of nodules of control group. (14.2 +/- 6.7) > i.v. group (5.3 +/- 4.1) > i.p. group (0.41 +/- 0.7) (p < 0.05). Weight of omental tumors showed Control group (0.246 +/- 0.136 g) > i.v. group (0.140 +/- 0.068 g) > i.p. group (0.051 +/- 0.017 g) (i.v.-i.p., p < 0.01). The mouse body weight decrease less in the i.p. group than in the i.v. group (p < 0.05) throughout this experiment. The results of this experiment demonstrated intraperitoneal sequential MTX/5-FU therapy was more effective than intravenous sequential MTX/5-FU therapy for potential peritoneal seeding and peritoneal micrometastases from the gastric cancer. Moreover, the side effect of intraperitoneal administration was milder than by the intravenous route.  相似文献   
103.
Newly registered active tuberculosis in children is under 300 persons a year in Japan, now. In order to lessen further and exterminate childhood tuberculosis in near future, physician have to make effort to find the infected children by good-timing thorough surveillance when he find an adult tuberculosis patient. Chemoprophylaxis could prevent the infected children from progressing to active disease. BCG vaccination in infantile period is still important in Japan, especially to protect young children from disseminated tuberculosis. Pulmonary tuberculosis in children is successfully treated with 6 months standard multi-drugs therapy.  相似文献   
104.
In order to study the subcellular heterogeneity of intracellular H+ concentration in reactive astrocytes, the pH in the nucleus and cytosol of cultured astrocytes was measured using a confocal laser scanning microscope (CLSM) and pH indicator dye, 5'(and 6')-carboxyseminaphthofluorescein (carboxy SNAFL-1). The change in intracellular pH was indexed by the fluorescence ratio (F535/F610) at an excitation wavelength of 514.5 nm. The in vitro fluorescence ratio increased as pH decreased. This ratio in the nucleus was significantly lower than that in the cytosol of astrocytes when perfused by HEPES-buffered Hanks' balanced salt solution (HHBSS) at pH 7.4. Acid stimulations of cells (pH 5.0) raised the fluorescence ratio in both nucleus and cytosol. However, the increase in the fluorescence ratio of the nucleus was less than that of cytosol. Treatment with a K+/H+ ionophore, nigericin (20 microM), reversibly nullified this cytosol-nucleus pH gradient. These findings suggest that a buffering mechanism(s) for maintaining of intracellular pH exists between the nucleus and cytosol, and a K+/H+ exchanger may act on the nuclear envelope to eventuate intranuclear pH maintenance in the living cells.  相似文献   
105.
Indole and indoline derivatives were selectively and temperature dependently synthesized via the intramolecular cross‐coupling reaction between the amino and aromatic bromine functionalities of 2‐bromophenethylamine derivatives in the presence of 10% palladium on carbon (Pd/C), 1,1′‐bis(diphenylphosphino)ferrocene (DPPF), and sodium tert‐butoxide (NaO‐t‐Bu) in mesitylene at 140 and 200 °C, respectively. The neutralization using acetic acid after formation of the indoline derivatives effectively promoted their aromatization, and the corresponding indole derivatives were obtained at 140 °C. Furthermore, various aryl groups were also introduced to the N‐1 position of the indole, pyrrole, and carbazole rings by their direct intramolecular arylation with aryl halides and a one‐pot protocol for N‐arylindole synthesis from 2‐bromophenethylamine was developed.

  相似文献   

106.
In order to reduce IDDQ testing time, it is important to reduce the number of IDDQ measurement vectors, because IDDQ measurement is a time-consuming process. For obtaining minimum number of IDDQ measurement vectors for sequential circuits, fault simulation needs to be performed without fault-dropping, thus requiring very high simulation time. In this paper we propose algorithms to select small number of IDDQ measurement vectors. The proposed algorithms can concurrently simulate multiple faults and use heuristics for selection of IDDQ measurement vectors to reduce simulation time. Experimental results are presented to demonstrate the effectiveness of the proposed method.  相似文献   
107.
Clinical aspects of leg ulcers are reviewed. Among the most important factors to be kept in mind are: localisation, features of the ulcers and surrounding skin, clinical history and general physical examination. Leg ulcers are most frequently caused by vascular diseases.  相似文献   
108.
109.
We raised mAbs to whole L5178Y leukemia/lymphoma (LL) cells to identify adhesion proteins involved in adherence between LL cells and marrow stromal cells. One mAb, 4C, and its subclones 4C.1 and 4C.2 inhibited adherence of L5178Y LL cells to MLT. a nontransformed murine marrow stromal cell line. These MoAbs are directed against CD45RA. Control anti-CD45 mAbs and isotype mAbs were non-inhibitory. Other anti-CD45 mAbs, M1/9.3, RA3-3A1/6.1 and RA3-2C2/1 do not compete with mAb 4C.1 for binding to the L5178Y cell surface, but mAb 4C.1 competes for binding of mAb RA3-2C2/1. Effects of mAb 4C on tyrosine-phosphatase activity of CD45 in L5178Y cells are minimal, suggesting direct involvement of CD45 as an adhesion protein.  相似文献   
110.
带楔块装置钢柱脚恢复力特性试验   总被引:2,自引:0,他引:2  
为避免钢结构露出型柱脚在地震中发生破坏,研究一种新的减震装置。该装置通过楔块滑动、弹簧变形和螺杆的塑性伸长来控制柱脚位移,同时消耗地震能量,达到消能减震的效果。采用方形空心钢管柱,分别对普通螺栓柱脚和带减震装置的柱脚进行低周往复加载试验,研究其恢复力特性。试验表明:普通螺栓连接的柱脚呈滑移型滞回特征;由于弹簧恢复和楔块切入,新型柱脚连接每次加载卸载均以原点为始终,呈无滑移型滞回特征。根据试验结果,得到了带楔块装置钢柱脚的无滑移型恢复力模型。研究结果表明,无滑移型减震连接的钢柱脚具有良好的抗震性能且简单易用。  相似文献   
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