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991.
Daniel Díaz Sánchez Andrés Marín López Florina Almenárez Mendoza Celeste Campo Vázquez Carlos García-Rubio 《Telecommunication Systems》2007,36(1-3):49-60
Mobile devices of new generation are able to connect to multiple networks and to constitute new infrastructureless networks. These dynamic environments require new security paradigms and automatic mechanisms to minimize user intervention. Our goal is the definition of a new concept of distance that considers the current domain constraints and the user preferences. This paper addresses some of the problems of these complex environments by using Multidimensional Scaling (MDS) techniques. We also propose collaborative mechanisms for automatic environment marking. Based on these ideas we have developed Pervasive Interaction Manager (PervsIM), a decision mechanism that selects the most appropriate network or peer to interact with. Besides we have defined an embedded access control module which ensures that PervsIM decisions are followed by all applications. Furthermore, several simulation results and implementation details outline how these results can be incorporated in today’s mobile devices. 相似文献
992.
993.
I Pérez Sánchez J Rivera Redondo A García Monforte M Mayoayo Crespo A Escudero Soto T Pintado Cros 《Canadian Metallurgical Quarterly》1998,83(10):946-948
Blastomycosis is an endemic systemic fungal infection that usually involves the lungs and superficial skin. Although head and neck involvement has been reported in the literature, no previous cases of neck mass resulting from direct extension of a pulmonary lesion have been published. We encountered an immunocompetent 31-year-old woman with a rapidly enlarging subcutaneous neck mass and a chronic upper lung infiltrate. Imaging studies showed contiguity between both lesions. Blastomyces dermatitidis was recovered from the sputum, and typical yeast was observed in fungal stains of needle aspirate from the neck mass. The patient responded favorably to a 6-month course of itraconazole. Blastomycosis should be considered in patients with subcutaneous neck masses in areas where this disease is endemic. 相似文献
994.
Experiments were carried out with seedlings of Quercus rotundifolia Lam., an evergreen schlerophyllous tree typical of the Spanish Mediterranean climate environments. Fruits were collected in two distant (800 km) populations located in the center (southern Spain) and northern border (northern Spain) of the area of distribution of the species. One-month-old potted plants were grown for 130 days in an enriched atmosphere of SO2 (0.23 ppm, 14 h/day) in controlled (growth chamber) conditions. Both northern and southern plants underwent a significant decrease in growth rate as a consequence of the treatment. Even so, plants appear to be quite resistant to SO2 compared with either more temperate or more productive species. The southern population was more sensitive to the treatment, as reflected by the bigger decrease in both growth and photosynthetic rates. Differences in resistance appear to be related to the biogeographic origin of the populations studied, which underlines the importance of biogeographic aspects in studies of resistance to air pollutants. 相似文献
995.
A Segovia Martínez C Pérez Fuentes J Torío Durántez MC García Tirado 《Canadian Metallurgical Quarterly》1998,22(9):562-569
OBJECTIVES: To find the social, demographic and family characteristics, the psychological malaise and reasons for consultation of normal and hyper-attenders at a primary care practice. DESIGN: Crossover study with a control. SETTING: Primary care. PATIENTS: 127 hyper-attenders (they attended the practice as often as, or more often than, the mean number of visits, stratified by sex and age) and 120 normal attenders chosen by stratified random sampling. INTERVENTIONS: Questionnaire with characterisation data, family demography, psychological malaise (Goldberg general health questionnaire) and reasons for consultation. RESULTS: To be considered a hyper-attender, the number of attendances per year ranged from > or = 8 (in 15 to 44-year olds) to > or = 20 (in men over 65). Hyper-attenders were about 12% of almost all groups, except in men between 45 and 64 and women over 64, in whom it was around 18%. We found no relevant differences between normal and hyper-attenders as to demography or perception of family function. In almost 60% of hyper-attenders and 34% of normal attenders (p < 0.001), psychological malaise was detected. CONCLUSIONS: If the definition of hyper-attenders is stratified by age and sex, their social and demographic characteristics are very different from in other studies, even though there are a similar number of them. However, these demographic and/or family characteristics are similar in normal and hyper-attenders. 相似文献
996.
997.
M Bustamante P Nos M Hoyos J Hinojosa JR Molés A García-Herola J Berenguer 《Canadian Metallurgical Quarterly》1998,90(12):833-840
The effects of smoking on the onset and clinical course of inflammatory bowel disease (IBD) have been widely debated. Although smoking appears to have a clearly unfavorable effect on the course in Crohn's Disease (CD), the relationship between smoking and localization of the disease is less clear. AIM: To evaluate, in our group of patients, the relationship between smoking and the development of ulcerative colitis (UC) or CD, and between smoking and the localization of CD in the large bowel or in other sites. PATIENTS AND METHODS: The smoking habits of 171 patients at the time of diagnosis were assessed with a questionnaire. Subjects were classified into three subgroups as smokers, nonsmokers and ex-smokers. Current smokers were grouped according to their level of consumption as those who smoked fewer than or more than 10 cigarettes per day. A total of 161 patients were studied (UC n = 69, CD n = 92). Patients with CD were divided into those with colonic disease and those with no colonic involvement. We evaluated the relationship between smoking and the form of IBD, localization (colonic or noncolonic) and the presence of perianal disease (PAD) in CD. The results were analyzed with the chi-squared test. RESULTS: Smoking was more frequent in patients with CD than in those with UC (72.8% vs 31.9%). Among patients with CD, more patients without colonic involvement were smokers (84.6% vs 64.2%). However, among patients with CD involving the colon, smoking was significantly more common (64.2%) than among patients who had UC (31.9%). CONCLUSIONS: Our findings confirm a relationship between smoking and CD. Smoking seems to be associated with some degree of protection of the colonic mucosa, especially in heavy smokers. 相似文献
998.
JJ Reina Zoilo M Ruiz Borrego JC Valenzuela Claros MJ Valladares Ayerbes P Borrega García A Viana Alonso JA Moreno Nogueira 《Canadian Metallurgical Quarterly》1998,15(2):97-99
Photosensitive epilepsy is relatively rare. However, a large proportion of individuals with epilepsy perceive that they are at an increased risk of a seizure whilst exposed to specific photic material. The difference between perceived and real risk may be due to inadequate education and misinformation. One half of the participants in the present survey could not recall being informed of the result of the 'gold standard' test for photosensitivity--intermittent photic stimulation during an electroencephalogram. Furthermore, approximately one-third of our sample were apparently given inaccurate and overcautious advice about their everyday exposure to photic material. Better information and advice is crucial to improve this situation in the future. The majority of people with epilepsy (>95%) who are not photosensitive can pursue activities that involve flickering or patterned light, encompassing educational, employment and leisure opportunities, without undue concern. 相似文献
999.
MJ Vázquez García R Olalde Carmona JA Juárez D Escárcega Barbosa 《Canadian Metallurgical Quarterly》1998,45(6):143-146
BACKGROUND: Intravenous Immunoglobulin (i.v.Ig) has been advocated as efficacious for Systemic Lupus Erytematosus (SLE) and Lupic Nephritis (LN) using high dosages, propitious a prolonged remission of SLE. MATERIAL AND METHOD: We show the case of a male patient 16 years old, with SLE diagnosis until 1993, and LN phase IV. He attend to hospital with a Lupic Crisis, positives ANAs, DNAds, ScL 427, C3 45, C4 13, IgG 179, urinary sediment: leukocytes 30-40 xc, erythrocytes 8-10 xc. Renal failure: BUN 243, seric Cr: 10.16. I.v. Ig administrated 400 mgs k do. And nephrologic assistance, NK. RESULTS: There was improvement after infusion, clinical and serological, persisting with renal failure. The mechanism by which i.v. Ig might have effected improvement in this patient was reviewed. CONCLUSION: The use in our patient with SLE and LN was satisfactory. Is difficult affirm categorical the outcome or failure of i.v. Ig in patients with SLE, even report founded are only few cases report. 相似文献
1000.