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951.
Palladium/silica catalysts of varying dispersities were submitted to the coking reaction with cyclopentane at 500°C. Temperature programmed oxidation curves reveal the presence of two peaks for carbon deposition on the metallic function: the first one near 250°C would correspond to coke deposited on palladium atoms of high coordination and the second one near 400°C would involve palladium atoms of low coordination. 相似文献
952.
MS Marín JM Martín Alonso LI Pérez Ordoyo García JA Boga JL Argüello-Villares R Casais K Venugopal W Jiang EA Gould F Parra 《Canadian Metallurgical Quarterly》1995,39(2-3):119-128
We have constructed a recombinant baculovirus containing the gene encoding the structural protein VP60 from the Spanish field isolate AST/89 of rabbit haemorrhagic disease virus (RHDV). Infection of cultured Spodoptera frugiperda Sf9 cells with this recombinant virus resulted in the production of high yields of VP60 protein which did not seem to assemble to form virus like particles, but was antigenically similar to the corresponding viral protein obtained from purified virions. A VP60-dose study showed that the recombinant protein was able to elicit a protective response in rabbits against a nasal challenge with 100 LD50 of RHDV. The effective dose able to protect 50% of the animals in the absence of adjuvant was found to be 10-25 micrograms of recombinant VP60. 相似文献
953.
PP Marín E Valenzuela NK Saito S Castro T Hoyl 《Canadian Metallurgical Quarterly》1996,124(6):701-706
BACKGROUND: Ten percent of the Chilean population is over 60 years old and general practitioners need an instrument to assess the degree of disability and multiple ailments of elders. AIM: To develop and use an instrument to assess elders consulting in primary care outpatient clinics. PATIENTS AND METHODS: An instrument to be used by general practitioners, aimed to assess bio-psico-social risk of elders was devised by the Geriatrics Program at the Faculty of Medicine of the Catholic University of Chile. The instrument was used in 100 elders (82 female) aged 71 +/- 8 years old consulting in a primary care outpatient clinic. RESULTS: The instrument took less than 5 minutes to be used. The most frequent risk factors found were living alone in 62% of subjects, falls in the last year in 47%, memory disturbances in 62%, overweight in 76%, visual impairment in 76%, urinary incontinence in 26% and depression in 76%. Thirty percent had difficulties to climb stairs and 4% had no support in case of severe disability. CONCLUSIONS: The applied instrument is fast to apply, easily understood by patients and detects problems associated with old age, that will help to plan primary care health programs. 相似文献
954.
Ethnic minority men, particularly Blacks and Hispanics, make up a significant proportion of all AIDS cases in the United States, with these cases linked primarily to homosexual or bisexual behavior and intravenous (IV) drug use. Difficulties in developing successful prevention strategies include (a) limited data on the prevalence of AIDS risk behaviors among minorities, (b) limited information on successful community interventions for minority populations, and (c) problems in using social networks for AIDS prevention. Suggestions are made to include culturally appropriate information in developing communication messages and to consider culture-specific values, norms, attitudes, and expectations in designing community interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
955.
We report the experimental measurement of moving space-charge domains in liquid He cooled ultrapure p-Ge using a movable capacitive probe to map the one-dimensional potential, electric field and space charge distributions along the conduction direction of rectangular samples at successive times. The data show dipole-type domains moving periodically through the sample in the direction of applied dc electric field. 相似文献
956.
P Morales Marín E Cases Viedma L Compte Torrero J Francés Va?o A Hernández Sojo V Marco Martínez 《Canadian Metallurgical Quarterly》1993,10(3):113-115
Given that forced spirometry is the main routine exploration in any laboratory of pulmonary functional assessment, we have analyzed the behaviour of O2 arterial saturation (SaO2) during such maneuver in patients with airflow chronic obstruction (AFCO), in order to verify any potential alterations. We have studied three groups of patients: Group A, control, 17 healthy subjects; group B, 18 patients with AFCO and initial saturation higher than 90%; group C, 15 patients with AFCO and saturation equal to or lower than 90%. Total duration of the maneuver was significantly higher in groups B and C compared with the control group (p < 0.001). In groups A and B, we did not observed any significant reductions in SaO2 with respect to the initial value, although we did observed such differences in group C (p < 0.001). None of the patients presented a subjective clinical disorder, although the absence of both complexity and risk suggest the convenience of including the oximetry as an additional parameter when conducting a forced spirometry in patients with AFCO and respiratory failure. 相似文献
957.
958.
P Anda W Sánchez-Yebra M del Mar Vitutia E Pérez Pastrana I Rodríguez NS Miller PB Backenson JL Benach 《Canadian Metallurgical Quarterly》1996,348(9021):162-165
BACKGROUND: Lyme disease and tick-borne relapsing fever are worldwide systemic borrelioses caused by several Borrelia species transmitted by hard ticks (family Ixodidae) and soft ticks (family Argasidae), respectively. A previous seroepidemiological study of Lyme borreliosis showed several serologically reactive patients with clinically atypical presentations, and this discovery led to the hypothesis that some of the cases of Lyme borreliosis had been caused by another borrelia organism. METHODS: Blood from patients in southern Spain who had suspected Lyme disease or relapsing-fever borreliosis was cultured before treatment began. Isolates of Borrelia spp were inoculated into several strains of mice of different ages. The 16S rRNA and flagellin in genes of Borrelia spp were sequenced by PCR and assessed by phylogenetic analyses. FINDINGS: We isolated a species of Borrelia from three patients with relapsing fever and from Ornithodorus spp ticks in southern Spain. This organism (refractory to in-vitro cultivation) caused a relapsing spirochaetaemia with multiple organ involvement in laboratory mice that recreated the human disease. Phylogenetic analysis showed that this organism is a previously unrecognised species. INTERPRETATION: We have discovered a new borrelia pathogen that is closely related to the other tick-borne agents of relapsing fever in Europe and Africa, and which causes a relapsing systemic disease with serological similarities to Lyme borreliosis. 相似文献
959.
A random sample of 1418 (40.8% male) Hispanics and 501 (46.1% male) non-Hispanic Whites were surveyed about their behavioral expectations for driving under the influence of alcoholic beverages (DUI). Hispanics reported more often than Whites that the effects of DUI would be driving carelessly, being angry at other drivers, feeling nervous, losing the respect of friends, feeling guilty, feeling too tired to drive, and losing their self-respect. There were gender differences among Hispanics but not among Whites. Hispanic abstainers reported the likelihood of the various outcomes more frequently than drinkers although drinking status produced no statistically significant differences among non-Hispanic Whites. 相似文献
960.
A Colell C García-Ruiz M Miranda E Ardite M Marí A Morales F Corrales N Kaplowitz JC Fernández-Checa 《Canadian Metallurgical Quarterly》1998,115(6):1541-1551
BACKGROUND & AIMS: Tumor necrosis factor (TNF)-alpha induces cell injury by generating oxidative stress from mitochondria. The purpose of this study was to determine the effect of ethanol on the sensitization of hepatocytes to TNF-alpha. METHODS: Cultured hepatocytes from ethanol-fed (ethanol hepatocytes) or pair-fed (control hepatocytes) rats were exposed to TNF-alpha, and the extent of oxidative stress, gene expression, and viability were evaluated. RESULTS: Ethanol hepatocytes, which develop a selective deficiency of mitochondrial glutathione (mGSH), showed marked susceptibility to TNF-alpha. The susceptibility to TNF-alpha, manifested as necrosis rather than apoptosis, was accompanied by a progressive increase in hydrogen peroxide that correlated inversely with cell survival. Nuclear factor kappaB activation by TNF-alpha was significantly greater in ethanol hepatocytes than in control hepatocytes, an effect paralleled by the expression of cytokine-induced neutrophil chemoattractant. Similar sensitization of normal hepatocytes to TNF-alpha was obtained by depleting the mitochondrial pool of GSH with 3-hydroxyl-4-pentenoate. Restoration of mGSH by S-adenosyl-L-methionine or by GSH-ethyl ester prevented the increased susceptibility of ethanol hepatocytes to TNF-alpha. CONCLUSIONS: These results indicate that mGSH controls the fate of hepatocytes in response to TNF-alpha. Its depletion caused by alcohol consumption amplifies the power of TNF-alpha to generate reactive oxygen species, compromising mitochondrial and cellular functions that culminate in cell death. 相似文献