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71.
72.
A dynamical model of container cranes is derived by using Lagrange's equation. When a ship is loaded or unloaded with containers, the total motion of the container load is divided into five fundamental sections. For each fundamental type of motion, the optimal control is calculated such that the corresponding trajectory satisfies the specified boundary conditions and that the swing of the container load during the transfer is minimized. A new algorithm which is employed for computing the optimal control is explained in detail. Some results of numerical computation are also shown. 相似文献
73.
The first successful growth of YFe2O4 single crystals was carried out by the floating zone method. The atmosphere to give suitable oxygen partial pressures for the crystal growth of YFe2O4 was determined. The mixtures of CO2 and H2 with the mixing ratio ranging over , or the equivalent CO2CO mixtures, and the growth speed of 2 mm/hour or slower were found to be the essential conditions. The as-grown boules were aggregates of large single crystal grains with the c-axes perpendicular to the growth direction. A typical separated single crystal was a rectangular chip of 3mm × 1.5mm × 0.5mm. A slower growth speed is suggested for obtaining a bigger single crystal. 相似文献
74.
Sotoo Asakura Hiroko Ueda Norio Ohnishi 《Drug development and industrial pharmacy》1993,19(13):1629-1636
The in vitro dissolution rates of ceftizoxime suppository were compared using a rotating dialysis cell method, a dialysis membrane method and the JP XI rotating basket method. Only small variations in the dissolution rates were found with the rotating dialysis cell method and the rotating basket method, while the dialysis membrane method indicated rather large variation than other methods. In the rotating basket method, it was observed that a part of suppository bases came out through the wire mesh of the basket and spread over the surface of the dissolution medium. In the case of dialysis membrane method, it seemed that the large variations in dissolution rate was depending on a skill of the apparatus used.
As to obtain a good results, a selection of the rotating dialysis cell method was important. In vitro dissolutions of Ceftizoxime(CZX) suppository by using the rotating dialysis cell method were very rapid and also consistent with the absorption characteristics reported previously by Motohiro after rectal dose in pediatric subjects. 相似文献
As to obtain a good results, a selection of the rotating dialysis cell method was important. In vitro dissolutions of Ceftizoxime(CZX) suppository by using the rotating dialysis cell method were very rapid and also consistent with the absorption characteristics reported previously by Motohiro after rectal dose in pediatric subjects. 相似文献
75.
M Nakayama Y Kobayashi Y Oshima N Uemura E Shindo K Tajika K Yanagisawa S Takahashi S Irie A Tojo 《Canadian Metallurgical Quarterly》1995,36(7):703-706
A 64-year-old woman with multiple myeloma, IgG lambda type Durie-Salmon Stage II, was admitted because of gradually developing anemia and increased blasts with abnormal karyotype in her bone marrow after 10 years of treatment. The chromosomal analysis showed 44, XX, del(5q), del(7q), -9, add(12p), -21, typical of secondary MDS due to the cumulative alkylating agents. Thrombocytosis concomitantly occurred with emergence of chromosomal abnormality, but the serum interleukin 6 level was not elevated, which suggested that it was related to development of secondary MDS. 相似文献
76.
The shrinkage rate of liquid CO2 droplets in water at 3°C was measured by the use of high-pressure vessel placed in a constant-temperature room. The change of the diameter of the droplet was observed at pressures of 28 MPa and 35 MPa using a time-lapse video camera. Bromocresol green was employed as a pH indicator, and was effective in monitoring the profile of carbonic acid distribution. When a droplet of liquid CO2 was injected, CO2 hydrate immediately formed and covered the surface of the droplet. The diameter of the liquid CO2 droplet reduced gradually at a rate of 5.0 × 10?7 m/s. It is predicted, from the viewpoint of ocean CO2 sequestration, that a thin film of hydrate will form at the interface of sea water and liquid CO2, and that the hydrate film will greatly control the dissolution of CO2 into sea water. 相似文献
77.
Y Okuyama M Yamada C Kondo E Satoh S Isomoto T Shindo Y Horio M Kitakaze M Hori Y Kurachi 《Canadian Metallurgical Quarterly》1998,435(5):595-603
The aim of this study was to evaluate whether long-term administration of L-arginine, a physiological substrate for the production of nitric oxide, improved blood pressure, heart rate, cardiac hypertrophy and particularly structural changes in the coronary and carotid artery of spontaneously hypertensive rats (SHR). The experiments started with three groups of 10-week-old animals: control Wistar rats, untreated SHR and SHR treated with L-arginine (SHR + L-arginine). L-Arginine was administered to SHR in a daily dose of 300 mg kg-1 intraperitoneally for 6 weeks. Blood pressure and heart rate were recorded each week. At the end of the experiment in one-half of each group heart weight and body weight were determined and the heart weight/body weight index was calculated. In the other animals, the cardiovascular system was perfused via the left ventricle with a glutaraldehyde fixative at 120 mmHg and the coronary and carotid arteries were processed for transmission electron microscopy. The inner diameter and wall thickness (tunica intima and tunica media) were measured on semithin sections. The reliability of the genetic feature in the SHR group was proved by the increased heart weight, heart weight/body weight index, wall thickness and wall thickness/inner diameter ratio of coronary and carotid arteries in comparison to the group of control Wistar rats. Long-term administration of L-arginine did not significantly influence blood pressure and heart rate in comparison with untreated SHR. Neither were any differences found in cardiac hypertrophy or the geometry of the coronary and carotid arteries (thickness of arterial wall, inner diameter, wall/diameter ratio). In conclusion, the changes in the cardiovascular system in SHR were not reversed, or even alleviated, by chronic treatment with L-arginine. 相似文献
78.
M Takamatsu M Tsunemoto Y Ota M Shimada T Shindo 《Canadian Metallurgical Quarterly》1976,29(6):421-425
Using sheep erythrocytes (SRBC) as the antigen, two subpopulations of spleen antigen-binding lymphocytes could be distinguished by a marked difference in the susceptibility of their receptors to trypsin. In unimmunized animals, 30% of the antigen-binding cells were trypsin-resistant, whereas at 5 days after immunization, 80-90% were trypsin-resistant, indicating an increase of about 50-fold in trypsin-resistant antigen-binding cells per spleen. In contrast, trypsin-sensitive cells per spleen were only 4-fold higher on day 5 than before immunization. The rise in % trypsin sensitivity preceded the increase in rosettes per spleen, implying that immunization produced a preferential increase in trypsin-resistant antigen binding cells partly by converting sensitive cells to resistant cells. After the 5th day, the trypsin sensitivity of antigen-binding cells slowly returned toward the unimmunized level, but a booster injection of SRBC restored trypsin resistance. Trypsin resistance was not lost in the presence of sodium azide or protein synthesis inhibitors. But a slightly increased trypsin susceptibility was conferred by 2-deoxyglucose, implying that glycolysis or the glycosylation of protein may be involved in maintaining trypsin resistance. 相似文献
79.
80.
Osteoprotegerin (OPG)-deficient mice exhibit severe bone loss including the destruction of growth plate cartilage. Using OPG-deficient mice, we attempted to clarify the differentiation and ultrastructure of osteoclasts located on the destroyed growth plate cartilage and trabecular bone matrix in long bones. In (-/-) homozygous OPG knockout mice, adjacent to the growth plate cartilage, the formation of bone trabeculae without a calcified cartilaginous core resulted in an irregular chondrocyte distribution in the growth plate cartilage. At the metaphyseal ossification center, TRAP-positive osteoclasts showed unusual localization on both type-II collagen-positive cartilage and type-I collagen-positive bone matrix. Osteoclasts located on cartilage matrix lacked a typical ruffled border structure, but formed resorption lacunae. During growth plate cartilage destruction, osteoclasts formed ruffled border structures on bone matrix deposited on the remaining cartilage surfaces. These findings suggest that, in OPG (-/-) mice, osteoclast structure differs, depending on the matrix of either cartilage or bone. Then, we examined the effects of OPG administration on the internal trabecular bone structure and osteoclast differentiation in OPG (-/-) mice. OPG administration to OPG (-/-) mice significantly inhibited trabecular bone loss and maintained the internal trabecular bone structure, but did not reduce the osteoclast number on bone trabeculae. For most osteoclasts, OPG administration caused disappearance or reduction of the ruffled border, but induced neither necrotic nor apoptotic damages. These results suggest that OPG administration is an effective means of maintaining the internal structure and volume of trabecular bone in metabolic bone diseases by inhibition of osteoclastic bone resorption. 相似文献