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101.
Paraquat (1,1'-dimethyl-4,4'-dipyridylium) is an herbicide associated with both accidental and intentional ingestion, leading to severe and often fatal toxicity. Prognosis is largely dependent on the amount of paraquat absorbed. Rapid identification of the symptoms of paraquat toxicity (burns or ulceration at the site of ingestion or injection, acute respiratory distress, and renal failure) can facilitate early treatment intervention to limit absorption. We report a case of a 71-year-old man with a suicidal ingestion of paraquat 2 days prior to presentation. Serum paraquat levels, time elapsed since ingestion, and clinical symptoms all indicated poor prognosis. The patient developed severe respiratory distress and progressive renal failure, and died 6 days after admission to the hospital.  相似文献   
102.
Presents a model suitable for computing images of absorption cross sections of thick tissue structures illuminated at near infrared (NIR) wavelengths from tomographic projection data. Image reconstruction is accomplished by solving a system of linear equations derived from transport theory. Reconstruction results using different algebraic solvers are shown for anatomical maps of the breast, derived from magnetic resonance imaging data, containing two simulated pathologies, in which case qualitatively good reconstructions were obtained. Evaluation of magnetic resonance (MR) data to optimize NIR optical tomographic imaging methods and to assess the feasibility of a combined MR-optical measurement scheme is discussed  相似文献   
103.
Cytoplasmic tyrosine kinases are composed of modular domains; one (SH1) has catalytic activity, the other two (SH2 and SH3) do not. Kinase specificity is largely determined by the binding preferences of the SH2 domain. Attaching the SH1 domain to a new SH2 domain, via protein-protein association or mutation, can thus dramatically change kinase function.  相似文献   
104.
Close to three-fourths of patients with chronic obstructive pulmonary disease (COPD) suffer from weight loss. Identifying a single cause for this is difficult, as several factors-including chronic mouth breathing, dyspnea, aerophagia, certain medications, and depression-often act in concert. Malnutrition can exacerbate symptoms of COPD by decreasing ventilatory muscle strength, exercise tolerance, and immunocompetence, and by increasing the risk of depression and anxiety. Goals of nutrition intervention are to prevent or reverse malnutrition without worsening the disease process and to improve respiratory function, thereby reducing morbidity and delaying mortality. Recommendations for intake of fats, carbohydrates, protein, and water must be individualized.  相似文献   
105.
In this paper, a new multiple negative-differential-resistance (MNDR) device based on a metal-insulator-semiconductor-insulator-metal (MISIM)-like structure with step-compositional InxGa1-x As quantum wells has been fabricated and demonstrated. The interesting MNDR phenomena are found in the current-voltage (I-V) characteristics of this device. At room temperature, the triple switching behaviours and quadruple stable operation states are obtained. In addition, the sixfold switching behaviors and a staircase-shaped I-V characteristic are observed at -105°C. A sequential carrier accumulation at InGaAs subwells and the potential lowering process are used to qualitatively explain the interesting MNDR phenomena. From the experimental results, it is shown that the studied device has good potential in multiple-valued logic applications  相似文献   
106.
The effects of the composition of bacteriological growth media on the light output in a chemiluminometric assay of beta-galactosidase in Escherichia coli using 1,2-dioxetane substrates has been studied. In this assay a basic conflict exists between conditions that promote optimal bacterial growth and those conducive to maximal chemiluminescence. Common medium ingredients such as yeast or beef extract, protein hydrolysates and lactose suppress light emission and/or lead to high backgrounds. Quenching of light emission is probably partly due to light absorption by medium ingredients such as oxgall, and partly to interference with the reaction triggering the chemiluminescent process. Elevated backgrounds are caused by the presence of high concentrations of protein hydrolysates, which interact with the alkali in the accelerator solution. Only two purposely developed media, i.e. ILM and Colicult are shown to reconcile the requirements of growth support with that of optimal luminescent properties.  相似文献   
107.
The study of the micromammalian parasite complexes in the Belorussian part of the evacuation zone of the Chernobyl nuclear station revealed 13 species of Coccidia and 30 species of ectoparasitic Arthropoda. Total increase of abundance and biodiversity of both parasites and their hosts was observed. The part of ectoparasites being epidemically hazardous was significantly increased. An analysis of a long-term dynamics of parasite abundance reveals their adaptation to new conditions in the Belorussia.  相似文献   
108.
从冷却曲线上相变段倾角最小原则出发,研究了新型激冷剂的配比与热分析法检测铸铁成分精度的关系,实验结果表明,能使相变段倾角最小的成分配比,也能提高对铸铁成分的热分析和检测精度。  相似文献   
109.
阐述了国内外羰基镍测定的各种方法以及在工业与环境保护等领域的应用状。  相似文献   
110.
GIS技术与微机制图   总被引:1,自引:0,他引:1  
地理信息系统(GIS)随着信息社会的发展愈发显示出强大的生命力。本文简要叙述GIS的重要作用及其发展进程中涌出出来的四个设计模型,总结了运用GIS国产软件平台MAPGIS制作遥感地质构造解译图的工作步骤和技术方法。  相似文献   
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