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排序方式: 共有1918条查询结果,搜索用时 15 毫秒
1.
N Usui S Kamata S Ishikawa T Sawai H Okuyama K Imura A Okada 《Canadian Metallurgical Quarterly》1996,31(2):258-262
Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months. The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis. 相似文献
2.
Inertinite concentrates from three Australian bituminous coals were hydrogenated at various temperatures ranging from 350 to 475 °C in the presence of tetralin without any added catalyst. Both conversion yields and microscopic observations of the benzene-extracted hydrogenation residues have revealed that the hydrogenation of the inertinite macerals becomes significant only > 400 °C, whereas the dissolution-hydrogenation of the accompanying vitrinite macerals occurs mainly between 350 and 400 °C. The major reaction pathway for the inertinite particles in the hydrogenation process appears to be one of initial mild carbonization followed by hydrogenation. A simplified reaction scheme is proposed which describes the reaction pathway involved in the hydrogenation of inertinite. 相似文献
3.
The morphologic changes and signal intensity of the spinal cord on preoperative magnetic resonance images were correlated with postoperative outcomes in 74 patients undergoing decompressive cervical surgery for compressive myelopathy. The transverse area of the spinal cord on T1-weighted images at the level of maximum compression was closely correlated with the severity of myelopathy, duration of disease, and recovery rate as determined by the Japanese Orthopaedic Association score. In patients with ossification of the posterior longitudinal ligament or cervical spondylotic myelopathy, the increased intramedullary T2-weighted magnetic resonance imaging signal at the site of maximal cord compression and duration of disease significantly influenced the rate of recovery. A multiple regression equation was then developed with these three variables to predict surgical outcomes. 相似文献
4.
Three phase partitioning (TPP) uses t-butanol and ammonium sulfate to precipitate enzymes and proteins from aqueous solutions. The method is useful both upstream with crude samples and downstream where a scaleable simple step is needed. About 25 enzymes and proteins have been isolated by various laboratories using TPP-t-butanol. The relation of t-butanol used in TPP, with n-butanol used as an extraction agent from Morton's work, is reviewed. Some t-butanol appears bound to TPP-precipitated proteins which are actually protein-t-butanol coprecipitates. They float above denser aqueous salts because bound t-butanol increases their buoyancy, similar to the behavior of many lipoproteins. On redissolving TPP-precipitated enzymes, total and specific activities usually are regained and sometimes increased. Sulfate ion-in large concentrations-likely exerts itself through its kosmotropic action as in conventional salting out. t-Butanol likewise appears to be a kosmotrope and crowding agent at room temperature or above, whereas C1 and C2 cosolvents (e.g., ethanol) do not so behave except at near or below zero temperatures. However, kosmotropy is not the entire origin of TPP, nor probably of conventional salting out. Electrostatic forces, capacity to force protein conformation tightening and protein hydration shifts, also contribute. Electrostatic forces, and the tendency for salt ions to bind and tighten protein molecule conformation, are indicated by the sharp pH dependency of both conventional salting out and TPP, around pH regions where proteins undergo conformation changes. Sulfate anion is densely-perhaps extraordinarily-hydrated, adding much to its effective size, and therefore it has a tendency to crowd or exclude proteins, when sulfate concentrations are in the 0.5 to 3 M range. 相似文献
5.
Hartung J. Jacquin A. Pawlyk J. Rosenberg J. Okada H. Crouch P.E. 《Selected Areas in Communications, IEEE Journal on》1998,16(1):42-55
This paper describes a prototype video coding platform meant for the conception and testing of multimedia products such as next-generation videophones. The platform is largely based on ITU-T Recommendation H.263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate coding of “head-and-shoulders” video material typical of real-time multimedia applications, video teleconferencing, and video telephony. These features consist of: (1) segmentation into objects of interest, (2) segmentation-based prefiltering, (3) model-assisted rate control, (4) adaptive vector quantization, and finally (5) segmentation-based postfiltering. In the spirit of Recommendation H.263, these enhancements are modular and can be selectively turned on or off, thereby enabling a wide variety of coding modes 相似文献
6.
Yoshiyuki Uno Akira Okada Kensuke Uemura Purwadi Raharjo Toshihiko Furukawa Kosaku Karato 《Precision Engineering》2005,29(4):171-455
A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds. 相似文献
7.
8.
Kazutaka Chibana Chaedong Kang Masashi Okada Koji Matsumoto Tetsuo Kawagoe 《International Journal of Refrigeration》2002,25(2):83
Water-silicone oil emulsion with an additive, (C2H5O)3SiC3H6NH2, was examined as a heat storage material. A spiral tube used as a heat exchanger was immersed in a low temperature bath and the emulsion was circulated in the tube to make ice continuously. Ice was separated from the ice–liquid suspension in an outlet tank. The amount of formed ice, the temperatures of the inlet and the outlet of the heat exchanger, and the temperatures in the tube wall were measured and the overall heat transfer coefficient and the heat flux through the tube were calculated. Experiments were carried out, varying the flow rate, the temperature of cooling brine, and the thickness of tube wall. The condition under which slurry ice was formed continuously without adhesion of ice to the cooling wall was clarified. Though decrease in the thermal resistance of the tube increased the rate of ice formation or raised the brine temperature, it narrowed the range of the flow rate and of the brine temperature in which slurry ice was formed continuously. 相似文献
9.
M Okada 《Computers and biomedical research》1992,25(5):417-434
An approach to the nurse scheduling problem is presented. The critical problem in nurse scheduling in a hospital is how to determine the day-to-day shift assignments of each nurse for a specified period in a way that satisfies the given requirements as much as possible, where the requirements differ greatly depending on the hospital. We present a method for constructing an agency-independent core procedure which can be tailored to the peculiar requirements of an individual hospital. As a basis, a formal analysis of the problem was performed, and a general scheduling procedure was established. Based on the method, a software system which produces a scheduling program for a given institution was developed. A declarative program that represents institution-specific information is generated through an interview with the user and incorporated into the general procedure. Some of the programming technicalities and an application of the system are also presented. 相似文献
10.
Phase-separated domains prepared in the two-phase region were dissolved at a temperature in the single-phase region, and their dissolution dynamics was studied by using the time-resolved light scattering (TRLS) technique and a scanning electron microscope (SEM). The time tps of preparation of domains was chosen to be long enough for phase separation to proceed into the late stage. The scattered light intensity at small wavenumbers increased before it attenuated. As tps increased, the increase at smaller wavenumbers became more significant and the peak intensity decreased only slightly with dissolution time. The characteristic wavenumber qm evaluated from TRLS and SEM followed the power-law relation qmt−0.3. 相似文献