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排序方式: 共有3546条查询结果,搜索用时 25 毫秒
51.
Nobuo Ishizawa Atsushi Saiki Takeshi Yagi Nobuyasu Mizutani Masanori Kato 《Journal of the American Ceramic Society》1986,69(2):18-C-
Crystals of yttria partially stabilized zirconia were grown by the arc-image floating-zone technique and studied by transmission electron microscopy. Crystals annealed at 1700°C consist of tetragonal precipitates and a cubic matrix. The platelike domains in a precipitate are twin-related tetragonal variants stacked alternately parallel to the (011) twin plane. The axial relations between the tetragonal precipitate and the cubic matrix are [100]tetragonal |[100]cubic , [011]tetragonal |[011]cubic . 相似文献
52.
53.
Restless legs syndrome (RLS) and periodic limb movements in sleep (PLMS) are disorders that are common and disturbing to uremic patients. The treatment of these is problematic. Eight patients on chronic hemodialysis and continuous peritoneal dialysis completed a double-blind placebo-controlled crossover study using incremental doses of pergolide up to 0.25 mg at bedtime for treatment of RLS and sleep disruption. Five patients (62.5%) noted subjective improvement in restless legs symptoms and sleep quality. Objective results were improved only slightly by treatment. The percentage of the first hour in bed during which leg movements occurred decreased from 20.5 +/- 6.0 to 11.5 +/- 3.3, p < 0.05. However, findings during sleep were less positive. The following measures were not significant between placebo and treatment: leg movements per hour of sleep [53.7 +/- 22.3 vs 35.8 +/- 11.8 (p = 0.2)]; and percentage of sleep time spent with leg movements [5.5% +/- 3.2 vs 4.4% +/- 1.4 (p = 0.37)]. Patients continued to have very disrupted sleep, and we could not document an objective improvement in sleep architecture. Thus, although pergolide at the dose of 0.25 mg at bedtime provided subjective improvement in symptoms of restless legs and quality of sleep, and objectively decreased leg movements during the first hour in bed, objectively sleep continued to be disrupted. In this small patient group, the response to pergolide was not uniform, and further investigation is required to test effectiveness at higher doses. 相似文献
54.
CsB3O5 has been found to be phase matchable for SFG down to 0.185 μm by mixing the fifth harmonic of a Nd:YAG laser at 1.0642 μm and the output of a KTP parametric oscillator pumped by the second harmonic of the same Nd:YAG laser at 20.0°C. Improved Sellmeier's equations and nonlinear optical constant of this crystal are reported 相似文献
55.
Infectious mononucleosis (IM) syndrome is typically caused by EBV, but also by drugs and other organisms such as CMV and HBV. It demonstrates a wide range of clinical and laboratory characteristics, presumably depending on the age of onset. However, associations of laboratory abnormalities with the clinical features have not been well documented. We evaluated here, the associations among patients with IM syndrome using of multiple regression (MR) and multiple logistic regression (MLR) analyses. We examined 90 (40 males, 50 females) patients, who were admitted to our hospital with IM syndrome. The diagnostic criteria were fever and presence of atypical lymphocytes (> 5% of the WBC or the count including monocytes > 5000/microliter), and at least 3 of 7 clinical features: tonsillitis, lymphadenopathy, skin rash, hepato-, spleno-megaly, hepatic dysfunction. The diagnosis of EBV was serologically confirmed in 41 cases. MR revealed that the higher age group tended to have lower platelet counts, and that lower platelet counts were associated with higher ALT levels. In addition, MLR revealed that patients with skin rash tended not to have splenomegaly. The frequency of splenomegaly was not related to age, contrary to the findings of previous reports. These findings are useful to differentiate IM syndrome based on laboratory data. 相似文献
56.
The efficacy of collagen-sponge to reduce postoperative scar formation was investigated in 65 Japanese white rabbits that received laminectomy in the 7th and 8th thoracic vertebra. The defect after laminectomy was filled by collagen-sponge in 25 rabbits, by free fat in 20 rabbits, and by nothing in 20 rabbits as controls. The animals were sacrificed 2, 4, 8 and 12 weeks and additional 5 rabbits of which defects were filled with collagen-sponge were sacrificed after 24 weeks. All the defects were examined histologically. At 4 weeks after laminectomy, the defects filled by collagen-sponge showed that fibrous tissue had invaded into the sponge, but there was no remarkable adhesion to the dura mater. At 8 weeks, the defect with collagen sponge showed foaming cells, and no thickening of the dura mater was observed. At 12 weeks, the grouping of foaming cells was partially replaced by fat cells. At 24 weeks, most of the foaming cells were replaced by fat cells, and the defect was then similar to that filled by free fat at 12 weeks. In contrast, the defect with no interposed membrane was already filled with fibrous tissue at 4 weeks, and adhesion to the dura mater was observed. Although the free-fat graft at 12 weeks postoperatively showed no remarkable adhesion around the dura mater, infiltration of fat tissue into the spinal canal was observed in 2 of 5 rabbits. These results indicated that collagen-sponge can be utilized as a new biomaterial to effectively prevent scar formation after laminectomy. 相似文献
57.
Tomotaka Hashimoto Nobuo Ishizawa Nobuyasu Mizutani Masanori Kato 《Journal of Materials Science》1988,23(3):1102-1105
The temperature dependence of the electrical resistivity and Seebeck coefficient was measured on single crystals of La1–x
Ca
x
MnO3(0 <x 0.3) and La1–x
Sr
x
MnO 3 (0 <x 0.4) grown by the arc-image floating zone method. The electrical conduction for La1–x
crystals withx 0.2 was of the activation type aboveT
c and of the degenerate type belowT
c, while that for the crystal withx = 0.1 was of the activation type over the whole measured temperature range between –170 and 400°C. The conduction behaviour of La1–
x
Sr
x
MnO3 was essentially the same as that of La1–x
Ca
x
MnO3 except that the conduction of the crystals withx = 0.3 and 0.4 was of the degenerate type aboveT
c. A distinct difference in Seebeck data was observed between the calcium and the strontium compounds. 相似文献
58.
Preparation of spherical fine ZnO particles by the spray pyrolysis method using ultrasonic atomization techniques 总被引:1,自引:0,他引:1
Tian-Quan Liu Osamu Sakurai Nobuyasu Mizutani Masanori Kato 《Journal of Materials Science》1986,21(10):3698-3702
An ultrasonic atomizer was used in the spray pyrolysis method to prepare fine, spherical and uniform ZnO particles. Almost spherical particles were obtained successfully which had a mean particle size of 0.15 m and had a very narrow particle size distribution. By using alcohol as the solvent, it was found that the particles do not have hollow shell layers which could usually be observed in the spray pyrolysis process by using water as the solvent. The morphology of the ZnO particles was strongly affected by the concentration of the starting solution. 相似文献
59.
Takashi Ogihara Tadashi Ikemoto Nobuyasu Mizutani Masanori Kato Yukuaki Mitarai 《Journal of Materials Science》1986,21(8):2771-2774
The Ta2O5 powders synthesized by the hydrolysis of tantalum pentaethoxide, Ta(OC2H5)5 in alcoholic solution were monodispersed fine oxide particles, which were a uniform, spherical shape, non-agglomerate, and had a narrow size distribution. They grew to 1.2m after ageing for 1 h after hydrolysis. Powder X-ray diffraction and differential thermal analysisthermogravimetric analysis showed the particles were amorphous and hydrated. These particles lost the water at 290° C and gave well-crystalline Ta2O at 740° C. Throughout these thermal processes, the particle morphology was kept almost the same. 相似文献
60.