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排序方式: 共有368条查询结果,搜索用时 31 毫秒
21.
Fumi Kojin Masanobu Mori Yumiko Noda Michio Inagaki 《Applied catalysis. B, Environmental》2008,78(3-4):202-209
Carbon-coated W18O49 powders were prepared from the mixture of para-ammonium tungstate with poly(vinyl alcohol) by heat treatment in inert atmosphere at a temperature between 750 and 900 °C for 1 h. The synthesized W18O49 crystals had prismatic morphology in small size, less than 0.5 μm in diameter and about 1 μm in length. Carbon-coated W18O49 was shown to have photoactivity under visible light irradiation by comparing the concentration changes of methylene blue, phenol and dimethylsulfoxide with time under the irradiation of visible light to that in the dark. Photoactivity of W18O49 was supposed to be due to the formation of OH radicals on the basis of the degradation of dimethylsulfoxide, its quantitative transformation to methanesulfonic acid. Carbon coating seemed to have various roles: to reduce WO3 to W18O49, to inhibit the sintering and crystal growth of W18O49 to keep them small size, and also to concentrate pollutants around W18O49 crystal by adsorption. 相似文献
22.
Basic fibroblast growth factor (FGF-2) is not only a potent mitogen for various cells but also a multifunctional factor with angiogenic and chemotactic activity, and the capacity to induce the synthesis of various proteinases and to modulate endocrine function. To clarify the role played by FGF-2 in the progression of pituitary tumor, we fused rat FGF-2 cDNA to the promoter SR alpha, consisting of the early promoter of SV40 and HTLV(I)-LTR, and we cotransfected GH3 cells with pSV2-neo by an electroporation method. After selection by G418, we obtained 7 neomycin-resistant clones. Southern blot analysis of genomic DNA revealed the presence of transfected rat FGF-2 cDNA in 4 of the 7 clones. To measure FGF-2 molecules, we established a new immuno-fluorometric assay system, using 3 monoclonal antibodies against different portions of human FGF-2. This assay had a minimum sensitivity of 10 pg/ml and cross-reacted neither with acidic fibroblast growth factor (FGF-1) nor insulin-like growth factor 1 (IGF-1), even at a concentration of 100 ng/ml. Although FGF-2 was undetectable in the culture medium of any of the clones, the cell homogenate contained a significant amount of FGF-2 (7.2 ng/mg protein) in 1 of the 4 FGF-2-transfected clones (GH3FGF(+)), whereas FGF-2 was not detected (< 5.2 pg/mg protein) in the cell homogenates of either the parent GH3 cells or the control cells transfected with pSV2-neo alone (GH3FGF(-)), GH3FGF(+) grew as adherent cells and formed epithelial sheets with a growth rate similar to that of control cells. The amount of prolactin(PRL) released by TRH was greater in GH3FGF(+) than that in GH3 or GH3FGF(-). On the other hand, the sensitivity to SRIF was increased in GH3FGF(+) compared with that in other clones. The findings of these in vitro studies indicate that FGF-2, if it is expressed in pituitary tumor cells, plays little if any role in cell growth but may modulate certain cell functions such as responsiveness to hormones. 相似文献
23.
Yamashita K. Kinoshita T. Takasaki Y. Maeda M. Kaji T. Maeda N. 《Electronics letters》1985,21(10):419-420
A negative-feedback AGC amplifier based on a new circuit configuration concept is proposed and monolithically integrated. The amplifier exhibits characteristics 2.5 times superior to those of the conventional AGC amplifier: 410 MHz bandwidth, 16 dB maximum gain and 18 dB gain dynamic range. 相似文献
24.
I Suemitsu H Maeda S Toyooka S Hato M Kaji T Ohya 《Canadian Metallurgical Quarterly》1998,46(3):312-317
BACKGROUND: Blister formation and tissue damage in bullous pemphigoid have been attributed to the release of eosinophil granule proteins--namely, to eosinophil derived cationic protein (ECP) and major basic protein (MBP). In the present investigation these eosinophil granule proteins were studied in the conjunctiva of patients with ocular cicatricial pemphigoid (OCP). METHODS: Conjunctival biopsy specimens obtained from patients with subacute (n = 8) or chronic conjunctival disease (n = 13) were analysed histologically and immunohistochemically using antibodies directed against EG1 (stored and secreted ECP), EG2 (secreted ECP), MBP, CD45 (common leucocyte antigen), CD3 (pan T cell marker), and HLA-DR (class II antigen). RESULTS: Subepithelial mononuclear cells, mast cells, and neutrophils were detected in all specimens. The number of mononuclear cells, neutrophils, CD45+ cells, CD3+ cells, and the HLA-DR expression were significantly higher in the subacute than in the chronic disease group. Some eosinophils were found in specimens from five of eight patients with subacute OCP, but in none of the patients with chronic disease. The eosinophil granule proteins (ECP and MBP) were found in the epithelium and substantia propria in patients with subacute conjunctivitis. CONCLUSIONS: Subepithelial cell infiltration in the conjunctiva greatly differs between subacute and chronic ocular cicatricial pemphigoid specimens. The findings suggest that eosinophil granule proteins may participate in tissue damage in acute phase of inflammation in OCP. 相似文献
25.
Y Kaji H Obata T Usui K Soya R Machinami T Tsuru H Yamashita 《Canadian Metallurgical Quarterly》1998,24(11):1441-1446
PURPOSE: To investigate the structural changes in corneal stromal collagen fibrils after excimer laser keratectomy in relation to the degree of corneal haze. SETTING: University of Tokyo Hospital, Tokyo, Japan. METHODS: Corneal haze was quantitatively measured by analyzing the light scattering in Scheimpflug images of the corneas of white rabbits after excimer laser keratectomy. Collagen fibril structure was examined using scanning electron microscopy after chemical digestion with sodium hydroxide solution; the same specimens were examined by transmission electron microscopy after re-embedding. RESULTS: Corneal haze reached a peak 4 weeks after excimer laser keratectomy and then gradually decreased. The collagen fibrils of the normal cornea were regularly arranged parallel to the surface of the cornea, with small interfibrillar distances. After excimer laser keratectomy, the arrangement was highly disordered, with increased interfibrillar distances. These structural changes were most prominent 4 weeks after excimer laser keratectomy. CONCLUSION: The structural changes in the collagen fibrils of the corneal stroma, especially the increase in interfibrillar distances and the disordered arrangement, were associated with corneal haze after excimer laser keratectomy. 相似文献
26.
T Hozumi K Yoshida T Akasaka Y Asami Y Ogata T Takagi S Kaji T Kawamoto Y Ueda S Morioka 《Canadian Metallurgical Quarterly》1998,32(5):1251-1259
OBJECTIVES: The purpose of this study was to evaluate whether transthoracic Doppler echocardiography (TTDE) can reliably measure coronary flow velocity (CFV) and coronary flow velocity reserve (CFVR) in the left anterior descending coronary artery (LAD) in the clinical setting. BACKGROUND: Coronary flow velocity measurement has provided useful clinical and physiologic information. Advancement in TTDE provides noninvasive measurement of CFV and CFVR in the distal LAD. METHODS: In 23 patients, CFV in the distal LAD was measured by TTDE (5 or 3.5 MHz) under the guidance of color Doppler flow mapping at the time of Doppler guide wire (DGW) examination. Coronary flow velocity in the distal LAD were measured at baseline and hyperemic conditions (intravenous administration of adenosine 0.14 mg/kg/min) by both TTDE and DGW techniques. Coronary flow velocity reserve was defined as the ratio of peak hyperemic to basal averaged peak velocity in the distal LAD. RESULTS: Clear envelopes of basal and hyperemic CFV in the distal LAD were obtained in 18 (78%) of 23 study patients by TTDE. There were excellent correlations between TTDE and DGW methods for the measurements of CFV (averaged peak velocity: r=0.97, y=0.94x + 0.40; averaged diastolic peak velocity: r=0.97, y=0.94x + 0.69; systolic peak velocities: r=0.97, y=0.91x + 0.87; diastolic peak velocity: r=0.98, y=0.95x + 1.10). Coronary flow velocity reserve from TTDE correlated highly with those from DGW examinations (r=0.94, y=0.95x + 0.21). CONCLUSIONS: Noninvasive measurement of CFV and CFVR in the distal LAD using TTDE accurately reflects invasive measurement of CFV and CFVR by DGW method. 相似文献
27.
T Kaji M Suzuki C Yamamoto Y Imaki A Mishima Y Fujiwara M Sakamoto H Kozuka 《Canadian Metallurgical Quarterly》1994,86(1):25-35
The accuracy and reliability of the TMJ Scale were originally determined in cross-validation studies on large, research-based patient samples. It had been assumed that the demographic characteristics and test responses of these research-based samples would be representative of the clinical population in which the TMJ Scale would ultimately find use. The present study on more than 10,000 patients that were evaluated for temporomandibular disorders in clinical practice demonstrates that the test scores, demographic variables, and the patterns of symptom severity that characterize the original TMJ Scale research sample accurately represent the general temporomandibular disorder patient population in which the TMJ Scale is now being used. The results suggest a high degree of confidence in the clinical efficacy of this assessment tool. The overall symptom severity of temporomandibular disorders was found to be normally distributed in the patient population. Women with temporomandibular disorders report a higher level of severity of all physical and psychological symptoms than men. This may explain the high female-to-male ratio in patients seeking treatment. However, a higher percentage of male temporomandibular disorder patients has clinically significant psychological and stress-related problems than do women. The severity and prevalence of symptoms associated with joint dysfunction and range of motion limitation are lower in older age groups, and the overall symptom severity of temporomandibular disorders is not higher in older age groups. However, the severity and prevalence of symptoms associated with joint dysfunction are greater in groups in which temporomandibular disorders have existed for longer durations, although pain levels do not follow this trend. There is also an association between time duration of the temporomandibular disorder and the severity of psychological problems and chronicity. Patients with chronic problems are symptomatically more impaired than those with acute problems. 相似文献
28.
Carbon coating of anatase-type TiO2 through their precipitation in PVA aqueous solution 总被引:1,自引:0,他引:1
Fine particles of photocatalytic anatase-type TiO2 prepared through hydrolysis of titanium-tetraisopropoxide were coated by carbon through their precipitation in poly(vinyl alcohol) (PVA) aqueous solution, followed by heat treatment at high temperatures of 400-1000 °C in a flow of high purity Ar. Without carbon coating, the phase transformation from anatase to rutile started above 600 °C, but it was suppressed up to 800 °C with carbon coating. Suppression of the phase transformation depended on the amount of carbon coated, apparent suppression being observed with carbon content above 5 mass%. The amount of carbon coated on anatase was controlled by changing the concentration of PVA in the solution. In order to have a carbon content of about 5 mass%, a PVA solution with more than 2 mass% had to be used. 相似文献
29.
Earlier studies in our laboratories demonstrated that particles of a number of snack foods that are retained on the dentition accumulate fermentable sugars and short-chain carboxylic acids (SCCA; acetic, formic, lactic, and propionic) to different degrees. The present study was undertaken to test the hypothesis that the accumulated SCCA can induce a gingival inflammatory response. Five periodontally and medically healthy subjects were given portions of plain doughnuts (high SCCA levels) or oatmeal cookie (low SCCA), or had the SCCA applied directly to the gingival margins of designated teeth. Subjects were given wax to chew, or nothing, as controls. Inflammation was assessed by measurements of subgingival temperature, flow rates of gingival crevicular fluid (GCF), and neutrophil emigration into GCF. Subgingival temperatures of the maxillary gingiva rose by 1.32 +/- 0.30 degrees C (mean +/- SE) 5 min after the subjects consumed the doughnuts and remained elevated for at least 1 hr. These values were significantly higher than those obtained from subjects after ingestion of oatmeal cookies (0.63 +/- 0.17 degree C; p < 0.01), consistent with the low levels of SCCA in the retained cookie particles. Wax chewing elicited a similar response, indicating a masticatory effect on the gingiva. Gingival temperatures in the unchallenged controls remained unchanged. Neutrophil emigration into the GCF was significantly elevated in subjects after doughnut consumption. Rinses with a solution of SCCA, or application of the SCCA to the gingiva, also brought about significant elevations in subgingival temperature and neutrophil emigration. The findings describe the inflammatory effects of food ingestion on the gingiva of healthy human subjects, and support the hypothesis that SCCA in the particles of retained food are at least partly responsible for the observed responses. 相似文献
30.
S Ikegawa J Hata K Nakatomi H Asaga M Kaji S Sugawara H Uno Y Izawa 《Canadian Metallurgical Quarterly》1995,20(3):251-263
In order to examine the optimal administration period and parameters for male fertility assessment, male rats were subcutaneously administered 0.2, 2 or 20 micrograms/kg of estradiol benzoate (E2B), a known testicular toxicant, for 4 weeks or 9 weeks before mating. After 4 weeks administration, suppression of body weight gain and food consumption, decreases in prostate and seminal vesicle weights, atrophy of Leydig cells, and mature spermatid retention at stages IX, X and XI were observed in the 2 and 20 micrograms/kg groups. In the 20, micrograms/kg group, decreases in epididymides weight and copulation index were also found but the number of sperm and sperm motility were not affected. In the 0.2 micrograms/kg group, no changes were noted in any parameters. After 9 weeks administration, decreases in testis weight and the number and motility of sperm were observed in the 20, micrograms/kg group, in addition to the changes found after 4 weeks administration. These results suggest that detailed histopathological evaluation and determination of accessory sex organ weights are sensitive for evaluating the effects of E2B on male fertility. Results with the 4-weeks treatment were comparable to those with the 9-weeks treatment in terms of these parameters. 相似文献