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41.
Fifteen paediatric patients with Salmonella meningitis were retrospectively reviewed. Presenting symptoms and signs included fever, vomiting, seizures, poor activity, diarrhoea and bulging anterior fontanelle in most patients. Seven out of eight patients with prolonged fever for > 10 days had neurologic sequelae; therefore, prolonged fever is a significant prognostic factor of a poor outcome (p < 0.005). All 15 patients had a brain ultrasound or computed tomography in the acute stage and 11 patients had abnormal findings. The 14 surviving patients were treated with a third-generation cephalosporin for at least 3 weeks. Seven patients (47%) made complete recoveries; two of them were treated solely with a third-generation cephalosporin. Only one mortality (6%) occurred and there were no relapses. In conclusion, high frequencies of prolonged fever, neuroimaging abnormalities and neurologic sequelae were seen in patients with Salmonella meningitis treated with third-generation cephalosporins. 相似文献
42.
N Alptekin S Se?kin S Do?ru-Abbaso?lu F Yelkenci N Ko?ak-Toker G Toker M Uysal 《Canadian Metallurgical Quarterly》1996,34(3-4):167-169
The effects of water-immersion restraint (WIR) stress on lipid peroxide, glutathione (GSH), glutathione peroxidase (GSH-Px), gamma-glutamylcysteine synthetase (gamma-GCS) and gamma-glutamyltranspeptidase (gamma-GT) activities in several tissues of rats were investigated. Hepatic and intestinal lipid peroxide levels were increased significantly in the WIR stress group. In both tissues, GSH levels were significantly decreased and gamma-GCS activity was significantly increased. In addition, gamma-GT activities remained unchanged in both tissues following WIR stress. However, lipid peroxide and GSH levels did not change in the stomach and brain in the WIR stress group compared to the control group. These results suggest that lipid peroxidation, but not the depression of GSH synthesis and/or the increase of GSH breakdown may be a factor in hepatic and intestinal GSH reduction following WIR stress. 相似文献
43.
加热到1173K的Cu-25at;%Al合金块状试样经723K60S等温淬火后其组织由片状的“羽毛状贝氏体(9R结构)和β_1'马氏体(18R结构)组成。当试样被离子束轰去进一步薄化后,在足够薄的区域内生成了许多2H结构的薄片马氏体。初步分析认为该薄片马氏体形成的原因是由于贝氏体生成时在试样内留下了高的应力场,当试样薄化到一临界厚度以下时,试样区的三维约束条件松弛使试样内的应力场触发了薄片马氏体的生成。这些薄片马氏体是通过位于贝氏体界面上位错的重新启动而长大的。 相似文献
44.
45.
Verrucous carcinoma is a variant of squamous cell carcinoma and should be distinguished from benign papilloma and well-differentiated nonverrucous squamous cell carcinoma. It is rare tumor of the sinonasal tract. Occasionally, conventional squamous cell carcinomatous components may be seen in verrucous carcinoma. This entity is called a hybrid verrucous squamous cell carcinoma. We report a case of hybrid verrucous squamous cell carcinoma occurring in the nasal cavity and paranasal sinus of a 67-year-old male. The removed mass shows the typical feature of verrucous carcinoma, but focally conventional squamous cell carcinomatous area is also noted. The treatment of this case follows verrucous carcinoma, but close follow up is mandatory because it may potentially spread to regional lymph nodes in contrast to pure form of verrucous carcinoma. 相似文献
46.
The anisotropically formed BaFe12O19 ferrites were prepared from the hot-rolled mill scale and silica was added to the ferrite during fine milling in the range 0.15 to 0.50 wt%. These ferrites were sintered at 1220° C for 2 h. The grain growth of the ferrites is dominantly influenced by the sizes of the silica added. Coarse-grain ( 1m) silica tends to promote discontinuous grain growth, which increases drastically with slightly increasing amounts of silica added, while fine-grain ( 0.013m) silica tends to retain fine grain microstructures with the same increasing amount of silica. The average grain size of the ferrite without silica addition was 8 to 10m. The size was increased to as large as 30m on addition of 0.15% coarse-grain silica and the microstructure was full of extremely large grains on the addition of 0.50% coarse-grain silica. 相似文献
47.
Many video service sites headed by YouTube know what content requires copyright protection. However, they lack a copyright
protection system that automatically distinguishes whether uploaded videos contain legal or illegal content. Existing protection
techniques use content-based retrieval methods that compare the features of video. However, if the video encoding has changed
in resolution, bit-rate or codec, these techniques do not perform well. Thus, this paper proposes a novel video matching algorithm
even if the type of encoding has changed. We also suggest an intelligent copyright protection system using the proposed algorithm.
This can serve to automatically prevent the uploading of illegal content. The proposed method has represented the accuracy
of 97% with searching algorithm in video-matching experiments and 98.62% with automation algorithm in copyright-protection
experiments. Therefore, this system could form a core technology that identifies illegal content and automatically excludes
access to illegal content by many video service sites. 相似文献
48.
Morphology and geometry of melted zones, cooling rates, microstructure and microhardness in the laser-glazed Fe-4%C-10%Sn alloy have been investigated. The computer simulation on the basis of the moving gaussian source model was used successfully to predict the maximum width and depth of the melted zone and the cooling rate. The microstructure from the surface to the bottom of the laser-melted zone is a non-crystalline phase, dendritic grains and a microcrystalline zone successively. Values of the averaged-spacing of the non-crystalline phase are 0.2056 and 0.1219nm, respectively; twinned martensites, having an axial ratioc/a of 1.128, existed in dendritic grains, and carbides of Fe3 C at the interdendritic regions; the microcrystalline zone was composed of -Fe and a new bet (a=0.415 nm,c=0.955 nm) phase. The different microstructure in the melted zone can be explained by the results of the heat flow calculation. A fine eutectic structure (-Fe + Fe3C) was observed in heat-affected zones. Microhardness of the eutectic structure can be predicted by the empirical relation of fracture stress to the interlamellar spacing of pearlite. 相似文献
49.
Tae Jo Ko Tae-weon Gim Jae-yong Ha 《International Journal of Machine Tools and Manufacture》2003,43(1):411
Thermally induced errors reduce the accuracy in precision machining, and a great deal of research has been presented on compensation for these errors in machine tools. However, during the transition period after commencing or stopping spindle rotation, thermal deformation behavior is very complex. In particular, the y-directional movement of the vertical machining center cannot be explained by thermal expansion alone because of the relationship between deformation and temperature. Thermal bending that is generated from the thermal gradient in the structure causes this movement. In the research described in this paper, a theoretical explanation and an experimental verification is given for the particular behavior of spindle thermal deformation. As it is not easy to map the relationship of the compensation model, separation of the steady from the non-steady state in the mapping process is strongly recommended. 相似文献
50.