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31.
MJ Mulet Pons MT Sarrión Ferre A Barea Montoro N Marín Rueda JJ Blanquer Grégori MA Melchor Penella 《Canadian Metallurgical Quarterly》1995,16(7):423-427
OBJECTIVE: To find the reasons which determine failures to comply with anti-flu vaccinations, so that these can be corrected and the coverage of this preventive action be increased. DESIGN: Observational crossover study, done by means of a telephone survey of people over 65. A questionnaire with closed questions, composed after a pilot study and validated by Cronbach's alpha. SETTING: Primary Care Centre (PCC). PATIENTS: We calculated a population sample for qualitative variables (_ = 0.05; p = 0.60; e = 0.05) of 294 people over 65, chosen from the PCC records, by means of random sampling (K = 4) stratified for age and discounting the telephone selection bias. MEASUREMENTS AND RESULTS: The proportion of vaccinated patients (60.9%) obtained in our study did not significantly differ from that in the general population. The percentage of patients included in the programme for the first time was 14%. Level of satisfaction among those vaccinated was 89.4%, with 8.9% of problems detected being light. Main causes of non-vaccination were: thinking that they didn't need it (63.5%), ignorance of the campaign (35.7%), fear of the reaction (24.3%), forgetting (10.4%). The main form of access to the campaign information was from the PCC, both through individuals and posters. Lack of information was statistically significant (p < 0.00001) as a determinant of non-vaccination, without other factors (age, sex, associated pathologies...) explaining these differences. CONCLUSIONS: Individualised and on-going health education by the PCC is fundamental. This would enable the identification of the group not vaccinated due to their express refusal and the recovery of non-vaccinated patients. 相似文献
32.
The initiator methionine transfer RNA (tRNA(fMet)) gene was identified on a 347 bp Eco RI-Hind III DNA fragment of the potato mitochondrial (mt) genome. The sequence of this gene shows 1 to 7 nucleotide differences with the other plant mt tRNAs(fMet) or tRNA(fMet) genes studied so far. Whereas the tRNA(fMet) gene is present as a single copy in the potato mt genome, a tRNA 'pseudogene' corresponding to 60% of a complete tRNA (from the 5' end to the variable region) and located at 105 nucleotides upstream of the tRNA(fMet) gene on the opposite strand was shown to be repeated at least three times. Furthermore, the physical environment of the tRNA(fMet) gene in the mt genome is very different among plants, which suggests that the tRNA(fMet) gene region has often been implicated in recombination events of plant mt genomes leading to important rearrangements in gene order. 相似文献
33.
34.
Sánchez-Meca Julio; Marín-Martínez Fulgencio; Chacón-Moscoso Salvador 《Canadian Metallurgical Quarterly》2003,8(4):448
It is very common to find meta-analyses in which some of the studies compare 2 groups on continuous dependent variables and others compare groups on dichotomized variables. Integrating all of them in a meta-analysis requires an effect-size index in the same metric that can be applied to both types of outcomes. In this article, the performance in terms of bias and sampling variance of 7 different effect-size indices for estimating the population standardized mean difference from a 2 × 2 table is examined by Monte Carlo simulation, assuming normal and nonnormal distributions. The results show good performance for 2 indices, one based on the probit transformation and the other based on the logistic distribution. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
35.
María Pinto Dora Sales Anne-Vinciane Doucet Andrés Fernández-Ramos David Guerrero 《Scientometrics》2007,72(2):345-370
The purpose of the study proposed in this paper is to evaluate the Spanish public university websites dedicated to the European
Higher Education Area (EHEA). To do so, the quality of these resources has been analysed in the light of data provided by
a series of indicators grouped in seven criteria, most of which were used to determine what information is made available
and in what way. The criteria used in our analysis are: visibility, authority, updatedness, accesibility, correctness and
completeness, quality assessment and navigability.
All in all, the results allow us to carry out an overall diagnosis of the situation and also provide us with information about
the situation at each university, thus revealing their main strengths, namely authority and navegability, and also their chief
shortcomings: updatedness, accessibility and quality assessment. In this way it is possible to detect the best practices in
each of the aspects evaluated so that they can serve as an example and guide for universities with greater deficiencies and
thus help them to improve their EHEA websites. 相似文献
36.
Rosa RicciardiChristine Gaillet Guylaine DucouretFrançoise Lafuma Françoise Lauprêtre 《Polymer》2003,44(11):3375-3380
The structure and rheological behavior of atactic poly(vinyl alcohol) (a-PVA) hydrogels prepared by freeze/thaw cycles were investigated as a function of polymer concentration and number of freeze/thaw cycles. The presence of phases with different mobilities was observed using 13C CP/MAS and DP/MAS NMR experiments. The degree of crystallinity of the a-PVA-rich phase was determined by 1H NMR free decay experiments. Measurements of the shear storage and loss modulus were performed at a fixed frequency of 1 Hz and a strain value of 0.1%, i.e. under conditions where the deformation imposed on the gel structure is entirely reversible. Results thus obtained showed that an increase in the number of freeze/thaw cycles induces an increase in the degree of crystallinity in the polymer-rich phase together with an increase in the storage modulus. The a-PVA hydrogels became more fragile as the number of freeze/thaw cycles was increased. Moreover, both the percentage of protons in a rigid environment measured by 1H NMR and the storage modulus values tended to a limiting value after six freeze/thaw cycles. These results show that the first five or six freeze/thaw cycles play a very important role in determining the hydrogel structure and rheological properties. A more detailed comparison of NMR and rheological data led to the conclusion that the storage modulus is mainly controlled by the a-PVA crystallinity while the hydrogen bond interactions have a much smaller contribution. 相似文献
37.
As the antibiotic arsenal expands with the development of new oral agents, selecting appropriate therapy is becoming more difficult. What are the therapeutic indications for the newer antimicrobials, and what advantages do they have over traditional agents? Drs Gleckman and De La Rosa discuss current issues related to antibiotic treatment and offer specific recommendations for the best use of the newer agents. 相似文献
38.
B. E. Elizalde M. Dalla Rosa C. R. Lerici 《Journal of the American Oil Chemists' Society》1991,68(10):758-762
Maillard reaction volatile compounds (MRV), prepared by heating a glucose-glycine solution, were tested as antioxidants in
soybean oil (SBO) thermoxidation. The volatiles were transferred into the oil by stripping with a stream of Nitrogen and substituting
the atmosphere above the oil with air containing MRV. Standard accelerated oxidation was performed by heating the SBO. Peroxide
value measurement and headspace gas Chromatographic analysis were carried out on all the samples. The MRV antioxidant activity
was evaluated by determining the effect of the induction period and the kinetic rate constant of peroxide and oxidation volatiles
formation. The MRV showed a significant antioxidant activity. The effectiveness was variable depending on MRV transfer method
to the oil, and the Maillard reaction extent was related to the browning level of glucose/glycine solution. It was found that
the maximum effect of MRV prolonged about three times the induction period and reduced the kinetic rate constant by half in
relation to the control sample. MRV affects oxidative stability of soybean oil by lengthening the induction period as well
as by decreasing the rate of oxidation at the propagation state and reducing the formation of hexanal. 相似文献
39.
Aqueous extracts of the coralline red algaeBossiella orbigniana have been shown to catalyze the enzymatic oxidation of arachidonic acid to a previously unreported ω6 eicosapentaenoic acid
product. This unique fatty acid contains a conjugated tetraene with absorption maxima at 293, 306, and 321 nm, and was identified
by spectral methods as 5(Z),8(Z),10(E),12(E),14(Z)-eicosapentaenoic acid. The compound was given the trivial name bosseopentaenoic
acid. Under experimental conditions, production of bosseopentaenoic acid was linear up to 2 hr and dioxygen was consumed.
Bosseopentaenoic acid, along with several other conjugated tetraenes, was also present in the algae endogenously as revealed
by a comparison of the ultraviolet (UV) spectra and the high-performance liquid chromatographic (HPLC) pattern of the purified
product and the organic extract ofBossiella. 相似文献
40.
Several polyimide resins were tested as possible scratch resistant coatings for aluminosilicate glass centrifuge tubes. Tubes with siloxane pretreatments provided the best adhesion between the polyimide and glass surface. Resins synthesized with an alkoxysilane group incorporated into the polyimide chain also showed improved adhesion, but the results were not as significant as when the pretreatment was used. Elastic recovery and effective Young's modulus of the polyimide coatings were calculated from nano-scratching. The results indicate that polyimides with a lower modulus, and higher elastic recovery, protected the glass surface best, exhibiting compression of the coating layer. An example was poly-4-4'-oxydiphenylene pyromellitimide (PMDA-ODA), whereas the coatings with a high effective Young's modulus and low elastic recovery ruptured. An example of a failed coating was poly-4,4'-carbonyldiphenylene 3,3',4,4'-biphenylenetetracarboximide (BPDA-DABP) which had low amount of elastic recovery, high effective Young's modulus and a large amount of flaking during macroscratch testing. 相似文献