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991.
The precipitation of carbides in the Fe-C system aged at constant temperature is simulated considering two transformation
kernels of complex reactions, involving different impingement and rate-time factors. The metastable and stable phase are identified
by deconvolution of the experimental kinetics. The activation energy of carbides is found to depend, slightly, on the transformation
kernel in which it is used. 相似文献
992.
993.
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995.
Jesús García-Cantalejo Victoriano Baladrn Pedro F. Esteban M. Angeles Santos Germn Bou Miguel A. Remacha Jos L. Revuelta Juan P. G. Ballesta Antonio Jimnez Francisco Del Rey 《Yeast (Chichester, England)》1994,10(2):231-245
We report the sequence of an 18,002 bp DNA fragment from the right arm of Saccharomyces cerevisiae chromosome XI. This segment contains nine complete open reading frames (ORFs), YKR401 to YKR409, and part of another ORF, YKR400, covering altogether 87·2% of the entire sequence. One of them, YKR400, encodes an NAD-dependent 5,10-methylene-tetrahydrofolate dehydrogenase. YKR404, YKR405 and YKR406 correspond to the previously characterized HBS1, MRP-L20 and PRP16 genes, coding for a translation elongation factor, a mitochondrial ribosomal protein and an ATP-binding protein, respectively. The putative product of YKR407 contains the zinc-binding region signature of neutral zinc metallopeptidases. The five other ORFs do not show significant homology to any known protein. The sequence data reported here have been assigned EMBL accession number Z27116. 相似文献
996.
G Rodríguez-Rumayor C Fernández Pérez A Delgado García M Carrasco Asenjo E Andradas Aragonés S de Juan García M Zimmermann Verdejo 《Canadian Metallurgical Quarterly》1993,100(1):9-13
The more commonly known statistical procedures, such as the t-test, analysis of variance, or chi-squared test, can handle only one dependent variable (DV) at a time. Two types of problems can arise when there is more than one DV: 1. a greater probability of erroneously concluding that there is a significant difference between the groups when in fact there is none (a Type I error); and 2. failure to detect differences between the groups in terms of the patterns of DVs (a Type II error). Multivariate statistics are designed to overcome both of these problems. However, there are costs associated with these benefits, such as increased complexity, decreased power, multiple ways of answering the same question, and ambiguity in the allocation of shared variance. This is the first of a series of articles on multivariate statistical tests which will address these issues and explain their possible uses. 相似文献
997.
The effect of the phosphoric and acetic acids concentration on the reduction mechanism of diacetyl on a mercury electrode is studied. Reaction orders with respect to these proton donors at potentials corresponding to the foot of the polarographic wave indicate that the acid species are liable to protonate the free radical resulting from the first electron transfer. 相似文献
998.
Using a second generation enzyme immunoassay (ELISA) for the detection of antibodies against Hepatitis C virus (HCV), we investigated the frequency of antibodies anti-HCV and the Alanine Aminotransferase (ALT) plasma levels of 200 patients without history of viral hepatitis, liver diseases, blood transfusions, intravenous drugs abuse, homosexuality, hemodialysis, infection by Human Immunodeficiency Virus (HIV), Hepatitis B virus (HBV), nor workers of health services. There plasma samples (1.5%), were positives for antibodies anti-HCV, all of these samples were confirmed by RIBA (Recombinant Immunoblot Assay). In these three patients, the ALT plasma level were more than two folds the normal upper limit, another six patients had high ALT levels but less than one fold the normal upper limit. None of the infected patients had any clues that suggested the possible way of infection in the clinic history. We concluded that the incidence of Hepatitis C in the studied patients is 1.5% and that the ALT levels could be used to identify Hepatitis C infection. 相似文献
999.
V Cechinel Filho AR Santos RO De Campos OG Miguel RA Yunes F Ferrari I Messana JB Calixto 《Canadian Metallurgical Quarterly》1996,48(12):1231-1236
We studied retrospectively the effect of long-term treatment with an inhaled corticosteroid on bronchial hyperresponsiveness (BHR) and clinical asthma in moderate-severe asthmatic subjects. Fifty-eight patients who had used beclomethasone dipropionate (BDP) over one year, were enrolled in this study. BHR was measured before and after treatment with BDP by the methods recommended by Japanese Society of Allergology. Moreover we examined the clinical factors and the frequency of acute exacerbations. The results as follows: 1) The mean age was 48.8 years and the mean asthma history was 9.2 years. The mean dose and mean time of BDP administration was 801 micrograms/day and 28.1 months, respectively. 2) Patients during BDP treatment over one year showed about 6-fold mean improvements in BHR, but there were many patients who showed no improvements in BHR. 3) We retrospectively divided all the patients into two groups. Namely, the improved group (n = 25) showed more than 4 fold improvement in BHR and unchanged group (n = 33), less than 4-fold. But there were no significant differences in clinical characteristics and %FEV1 during treatment with BDP. 4) The unchanged group had more near fatal episodes in the past than the improved group. 5) There was significant decrease in acute exacerbation during treatment with BDP, but the unchanged group had more acute exacerbations than the improved group during treatment with BDP. These results indicates that there are many patients who had no improvement on BHR with long term BDP treatment and they have more acute exacerbations due to various stimuli. In conclusion, asthma is recognized chronic inflammatory disease and inhaled corticosteroid therapy has been recommended as the first line therapy. We must further study the clinical problems and underlying mechanisms concerning about treatment with an inhaled corticosteroid. 相似文献
1000.