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131.
We describe cystic lymphangiomatosis with intestinal bleeding developing multiple lymphangiomas in the small intestine, mesentery, mesocolon, omentum, retroperitoneum, and spleen. Small intestinal fluorography showed multiple polypoid lesions, mainly in the jejunum. Ultrasonography, computed tomography, and magnetic resonance imaging showed diffuse cystic tumors in the mesentery and spleen. Cystic lymphangiomatosis was proved by histologic findings of the biopsied specimen at laparotomy.  相似文献   
132.
Residual stresses induced by cooling down from the elaboration process in SiC/Ti-15-3 composite were calculated by the finite element model using MARC and MENTAT software. An analytical model (derived from those of Eshelby and of Mikata and Taya) already used for ceramic matrix composites has also been used in this study for elementary composites. The influence of uncertainty on thermomechanical properties and also the influence of fibre packing and spacing were also studied. Then, evolution (relaxation) of the thermal residual stresses (TRS) during a fatigue test were investigated. Results show that the TRS decreased rapidly during the first cycles and then became almost constant at about one-third of their initial values. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
133.
An episode of malignant hyperthermia occurring in a 42-year-old man undergoing hypothermic cardiopulmonary bypass is reported. Malignant hyperthermia is a syndrome initiated by a hypermetabolic state of skeletal muscle. A patient presented for correction of an acyanotic tetralogy of Fallot. The coincidental usage of hypothermic cardiopulmonary bypass obscured the classical presenting sings and symptoms of the malignant hyperthermia. And the disease of tetralogy of Fallot made the syndrome difficult to manage. Although the clinical diagnosis of malignant hyperthermia is difficult to be confirmed, when it is suspected, it is prudent for the case to be initially treated as malignant hyperthermia.  相似文献   
134.
A 16-ns 1-Mb CMOS EPROM has been developed utilizing high-speed circuit technology and a double-metal process. In order to achieve the fast access time, a differential sensing scheme with address transition detection (ATD) is used. A double-word-line structure is used to reduce word-line delay. High noise immunity is obtained by a bit-line bias circuit and data-latch circuit. Sufficient threshold voltage shift (indispensable for fast access time) is guaranteed by a threshold monitoring program (TMP) scheme. The array is organized as 64 K×16 b, which is suitable for 32-b high-performance microprocessors. The active power is 425 mW, the programming time is 100 μs, and the chip size is 4.94×15.64 mm2  相似文献   
135.
Spherical Si solar cell, which is made up of Si spheres with a diameter of approximately 1.0 mm, is expected to be a promising candidate for low consumption of Si feedstock and simple process technology. This paper describes the formation process and the structure of a concentrator module in detail. The concentrator lens was formed by casting with ultraviolet light hardening resin. The concentration ratio was 4.4 times and the pitch between the spheres was 2.0 mm. By this module design, it was possible to realize a consumption of the Si feedstock of about 3.0 g/W. Conversion efficiencies of 11.3% from single-sphere cell, 8.5% from a 23-spheres module and 5.2% from a 105-spheres module under AM1.5, 100 mW/cm2 illumination were achieved.  相似文献   
136.
Early endothelial injury may play a role in the development of transplant arteriosclerosis. The present study documents early endothelial changes using a rat aortic graft model. Abdominal aortic allografts from PVG rats were orthotopically transplanted to DA rats. Controls were DA to DA transplants. Endothelial cell (EC) injury, regeneration, and leukocyte infiltration in the intima were evaluated using scanning electron microscopy and histological and immunocytochemical techniques. Nontransplanted aortic segments showed partial loss of ECs after 1 or 2 hr of preservation. Control isografts demonstrated extensive EC denudation and neutrophil adherence to residual ECs at 1 day post-transplantation. After 3 days, isografts showed continued regeneration of ECs in the central area and ingrowth of endothelium from both clamped sites in the recipient aorta. Reendothelialization was complete by day 14. Allografts showed similar findings to isografts up to day 3. In contrast to isografts, however, there was a secondary EC loss beginning at day 7. Monocytes/macrophages and T cells were noted to be adherent to residual ECs in 7- and 14-day allografts. At 20 days, ECs were absent from the luminal surface in the center of allografts. Endothelium did extend from clamped sites toward the midgraft region as in isografts. By 60 days allografts were completely reendothelialized. These results demonstrate that in both isografts and allografts there is initial EC loss due to mechanical trauma and ischemia/reperfusion injury, followed by partial reendothelialization. This latter process continues unabated in isografts, whereas in allografts the secondary EC loss occurs due to an allogenic response. This is followed by complete reendothelialization that occurs during the concurrent development of significant intimal hyperplasia.  相似文献   
137.
Two different hydroxyapatites with the particle sizes of 3.9 and 1.69 μm were chosen. Slurries with initial hydroxyapatite concentration of 15 vol% were prepared. Different cooling rates from 2 to 14°C/min were utilized. The specimens were sintered at different temperatures of 1250–1350°C. The phase composition (by X‐Ray Diffraction), microstructure (by Scanning Electron Microscopy), mechanical characteristics, and the porosity of sintered samples were assessed. The porosity of the sintered samples was in range of ~57–83%, and the compressive strength varied from ~1.7 to 15 MPa. The mechanical strength of the scaffolds increased as a function of cooling rate and sintering temperature.  相似文献   
138.
In this work, the degradation phenomena and the release kinetics of an active molecule from matrices systems made of random copolymers of ε-caprolactone (CL) and l-lactide (LA) were investigated by exposing the matrices, shaped as thin films, to simulated physiological environments. α-tocopherol was incorporated into the films as hydrophobic model molecule with the aim to investigate both its release pattern and its effect on erosion phenomena. In particular, the films have been kept at controlled conditions (temperature, stirring, pH) and they were characterized in terms of weight loss, water uptake, thermal properties, and change of number average molecular weight, in order to explain the molecule release kinetics and the degradation pathways of the copolymers. The main findings of this study are that the erosion phenomena take place significantly only when a critical value of the molecular mass was obtained in the sample; that the presence of the drug stabilizes the matrix and it decreases the rate of molecular mass decrease; and that crystallinity, reducing the chain mobility, causes lower erosion rates.  相似文献   
139.
Tenobe somen (TS) noodles are traditional Japanese wheat-based noodles that are produced manually using a sophisticated method called tenobe (literally, "hand stretched"). In the tension test, both the tensile strength and extensibility of TS noodles were greater than those of machine-made (MS) noodles. In the biting test, the chewy texture of TS noodles was realized in the analysis of the force-deformation curves of each type of somen noodles. The creep test indicated a clear difference between the external and internal elasticity of TS noodles. The texture of TS noodles appeared to change dramatically during storage in the rainy season. In addition, firm and chewy textures of TS noodles stored for 20 mo were observed. Similar to the results from our previous study, TS noodles exhibited significantly higher dityrosine content than the flour used for their manufacture. However, the increase in the dityrosine content during the manufacturing process was not observed in the case of MS noodles. Although clear textural differences were observed between TS noodles stored for 0 and 20 mo, the dityrosine contents of TS noodles at each stage were not largely different.  相似文献   
140.
Abstract: The effect of sensory and extrinsic attributes on consumer intentions to purchase the Japanese traditional fermented soybean product natto was evaluated using conjoint analysis. Six attributes with 2 levels each were chosen and manipulated: price (high compared with low), the country of origin of the soybeans (domestic compared with imported), stickiness (strong compared with moderate), smell (rich compared with moderate), attached seasonings (attached compared with no attached seasonings), and the environmental friendliness of the packaging (high compared with low). A fractional factorial design was applied and 8 hypothetical product labels were produced. A sample of 479 Japanese housewives ranked these product labels based on their purchase intentions. Overall purchase intention was affected by country of origin, attached seasonings, and price; those attributes accounted for 81.0%, while the sensory attributes of the product accounted for 19.0% of purchase intents. In order to estimate market segments for the natto products based on consumer preference, a cluster analysis was performed. It identified 4 segments of consumers: 1 oriented to attached seasonings, another conscious of the price, and the other 2 oriented to origins. The behavioral and demographic characteristics of the respondents had a limited influence on segment membership. Practical Application: This research was conducted to understand how consumers valuate various sensory and nonsensory product attributes based on their assessment of the overall product in the case of Japanese fermented soy product (natto). The data of this research would be of great importance both in understanding consumer behavior and in designing strategies for product development.  相似文献   
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