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Remarkably rapid nitriding which is independent of diffusion theory based on the thermal activation process, was observed during nitriding of austenitic Fe-Ni-Cr steels containing 16 and 19 mass% chromium. Increase of the chromium content in the alloys yielded increasing thickness of the nitrided layer, i.e. the internal nitriding theory did not hold in the nitriding. No rapid nitriding was observed in steels containing less than 13 mass% chromium. Hence the limiting concentration of chromium for the rapid nitriding will lie between 13 and 16 mass% chromium. A solution to the problem of abnormalities arising during nitriding of practical austenitic stainless steels which have been investigated since 1972, has been presented experimentally by nitriding various chromium-containing steels. Based on the experimental results, the origin of the rapid nitriding is discussed in connection with the free-energy function of Cr2N and CrN to temperature. In particular, a plateau of nitrogen concentration measured in the nitrided layers leads to the conclusion that a forced nitrogen diffusion in the layer resulted in the rapid nitriding. 相似文献
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A Yoshimura Y Yamano A Gemma K Yoshimori K Hayashihara Y Taniguchi K Uematsu M Shibuya S Kudoh H Niitani 《Canadian Metallurgical Quarterly》1993,20(4):503-508
We conducted an early phase II trial in advanced non-small cell lung cancer (NSCLC) to evaluate response efficacy of a combination of Cisplatin (CDDP) and Carboplatin (CBDCA). The twenty-six patients in the study had had no previous treatment. They received a sequential administration of 300 mg/m2 CBDCA and 80 mg/m2 CDDP with approximately 3,500 ml of hydration on day 1 every 4 weeks. All patients were evaluable for response and toxicity. Ten (38.5%) of all assessable patients achieved a partial response (95% confidence interval, 19.8-57.2%). Response rates for patients with stage III A, III B and IV- disease were 40.0 (2/5), 70.0 (7/10) and 9.1% (1/11), respectively. Response rates for patients with squamous cell carcinoma, adenocarcinoma and large cell carcinoma were 35.7 (5/14), 45.5 (5/11) and 0.0% (0/1), respectively. The median survival time (MST) of all patients was 11 months. The MST for patients with stage III disease was 14 months; for those with stage IV disease it was 7 months. The MST for responding patients was 15 months and for not responding patients 5 months. Major toxicities were hematologic and gastrointestinal, and the dose-limiting factor was thrombocytopenia. This combination chemotherapy was effective against NSCLC with tolerable toxicities. Further trials are warranted to determine the efficacy of the combination chemotherapy. 相似文献
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Mireia Casanovas Irene Reyes-Resina Alejandro Lillo Jaume Lillo Raul Lpez-Arnau Jorge Camarasa Elena Escubedo Gemma Navarro Rafael Franco 《International journal of molecular sciences》2021,22(5)
Methamphetamine is, worldwide, one of the most consumed drugs of abuse. One important side effect is neurodegeneration leading to a decrease in life expectancy. The aim of this paper was to check whether the drug affects one of the receptors involved in neurodegeneration/neuroprotection events, namely the adenosine A2A receptor (A2AR). First, we noticed that methamphetamine does not affect A2A functionality if the receptor is expressed in a heterologous system. However, A2AR becomes sensitive to the drug upon complexes formation with the cannabinoid CB1 receptor (CB1R) and the sigma 1 receptor (σ1R). Signaling via both adenosine A2AR and cannabinoid CB1R was affected by methamphetamine in cells co-expressing the two receptors. In striatal primary cultures, the A2AR–CB1R heteromer complex was detected and methamphetamine not only altered its expression but completely blocked the A2AR- and the CB1R-mediated activation of the mitogen activated protein kinase (MAPK) pathway. In conclusion, methamphetamine, with the participation of σ1R, alters the expression and function of two interacting receptors, A2AR, which is a therapeutic target for neuroprotection, and CB1R, which is the most abundant G protein-coupled receptor (GPCR) in the brain. 相似文献
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In Rogerson and Restall’s (J Philos Log 36, 2006, p. 435), the “class of implication formulas known to trivialize (NC)” (NC abbreviates “naïve comprehension”) is recorded. The aim of this paper is to show how to invalidate any member in this class by using “weak relevant model structures”. Weak relevant model structures verify deep relevant logics only. 相似文献
6.
Laura Gosalbo Mireia Barrot Gemma Fabriás Gemma Arsequell Francisco Camps 《Lipids》1993,28(12):1125-1130
To develop a synthesis of tritiated cyclopropene fatty acids (CPFA), compounds that should prove useful for affinity labeling
of desaturases in insect pheromone biosynthetic studies, a series of novel, selectively deuterated CPFA analogues was prepared
and characterized. In methyl [16-2H]12,13-methylene-12-hexadecenoate, the incorporation of deuterium was achieved by treatment of the corresponding ω-chloro
derivative with sodium borodeuteride in dimethylsulfoxide at 70°C for 24 h (67% yield) following conventional procedures.
Alkylation of the tetrahydropyranyl derivative of 13-tridecynol in the presence of lithium diisopropylamide in tetrahydrofuran
at −20°C with 1-chloro-3-iodopropane in hexamethylphosphoramide, followed by Jones oxidation of the crude product, yielded
16-chloro-12-hexadecynoic acid (54%), which was esterified to the corresponding methyl ester by treatment with potassium carbonate
and methyl iodide in dimethylformamide. Treatment of this acetylenic ester with ethyldiazoacetate in the presence of activated
copper-bronze as catalyst followed by hydrolysis in KOH solution at room temperature yielded 16-chloro-12,13-(carboxymethylene)-12-hexadecenoic
acid. This diacid was treated with excess oxalyl chloride to give the corresponding diacyl chloride, which was decarbonylated
in a diethyl ether solution with zinc chloride, and the cyclopropenium ions thus formed were added at −40°C to a methanolic
sodium hydroxide solution of sodium borohydride to give methyl 16-chloro-12,13-methylene-12-hexadecenoate. Analogous procedures
were followed to prepare methyl [17-2H]10,11-methylene-10-hexadecenoate, methyl [17-2H]11,12-methylene-11-hexadecenoate and methyl [17-2H]12,13-methylene-12-hexadecenoate from the corresponding diacids using sodium borodeuteride in the reduction of the cyclopropenium
ions. Alternatively, methyl [2,2,3,3-2H4]hexadecynoate, prepared by reaction of methyl 2,11-hexadecadiynoate with magnesium in deuterated methanol at room temperature,
was submitted to the above cyclopropenylation and reductive decarbonylation sequence to give methyl [2,2,3,3,17-2H5]-11,12-methylene-11-hexadecenoate. In summary, complementary methods for the selective incorporation of one to five deuterium
atoms into cyclopropene fatty acids, at different sites, in moderate to high yields have been developed. The methods should
easily be applicable to the preparation of the corresponding tritiated analogues. 相似文献
7.
Rosario?Zamora Gemma?Gómez Francisco?J.?HidalgoEmail author 《Journal of the American Oil Chemists' Society》2002,79(3):267-272
13C NMR spectra of oil fractions obtained chromatographically from 109 vegetable oils were obtained and analyzed to evaluate
the potential use of those fractions in the classification of vegetable oils and to compare the results with the NMR analysis
of complete oils. The oils included the following: virgin olive oils from different cultivars and regions of Europe and north
Africa; “lampante” olive, refined olive, refined olive pomace, hazelnut, rapeseed, high-oleic sunflower, corn, grapeseed,
soybean, and sunflower oils; and mixtures of virgin olive oils from different geographical origins. Oils were divided into
two sets of samples. The training set (98 samples) was employed to select the variables that resulted in significant discrimination
among the different oil classes. By using stepwise discriminant analysis, more than 98% of correct validated assignments were
obtained; these results were confirmed when applied to the test set (11 blind samples). Results suggest that the use of oil
fractions considerably increases the discriminating power of NMR in the analysis of vegetable oils. 相似文献
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