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In this study known mixtures of four or five fatty acid methyl esters were analyzed collaboratively by gas chromatography with flame ionization detectors. The experimental data was treated statistically to examine inter- and intralaboratory scattering. More-over the effect of the use of correction factors was investigated. Even if only the specific analytical values that scattered a little were chosen, the averages of such values did not always approach the actual values. In some laboratories a sort of regularity was observed in the deviation of analytical values from real values throughout the analyses of four samples. The application of correction factors to the analytical values obtained by these laboratories resulted in a considerable decrease of interlaboratory scattering and deviation from the real values. When a constant amount of sample was injected, intralaboratory scattering was decreased, whereas interlaboratory scattering was not. Injection of large sample sizes caused deviation. From this collaborative study it was recommended that 0.5–1.0 μl of 20% solution be injected. Presented at the JOCS-AOCS Joint Meeting, Los Angeles, April 1972.  相似文献   
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A novel 1,3,5,7-tetramethylcyclotetrasiloxane (TMCTS)-vapor annealing method was developed for improving the mechanical strength of porous silica films with a low dielectric constant. TMCTS molecules react with Si-OH groups on the pore wall surfaces to form the polymer network which results in the high hydrophobicity and reinforcement of the silica wall. This method can be used to recover plasma damages induced by etching and ashing in fabricating Cu/low-k interconnects.  相似文献   
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It is shown here that if NC = P , the NC hierarchy collapses. We give two proofs for this. From the point of view of a circuit for circuit evaluation, the assumption that NC = P implies that any polynomial size circuit can be transduced into a polynomial size and poly‐log depth circuit. Such a parallelization property can be applied not only for uniform circuits but also for nonuniform circuits. This interesting property suggests that the assumption NC = P would be false. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(2): 46–50, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20488  相似文献   
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The septate gregarine parasites of flour beetles (Tribolium spp.) include Gregarina minuta Ishii, 1914, a relatively small species in which both primite and satellite possess an obvious protomerite, and a larger species that lacks the satellite protomerite. The latter species has been placed in the genera Didymophyes and Hirmocystis by various authors, but studies reported here demonstrate that this species, herein described as Gregarina triboliorum, exhibits early pairing and produces oocyst chains, both characteristics of the genus Gregarina. The oocysts of this new species are described for the first time. In addition, experimental infections using oocyst from single gametocysts reveal that oocyst chain number is variable but is typically 1, 2, or 4. Prior experiments involving a related beetle, Tenebrio molitor, demonstrated extreme host specificity within the 4 Gregarina species parasitizing larval and adult hosts. However, G. triboliorum is not limited either stadially or specially, infecting both adults and larvae of Tribolium confusum and Tribolium castaneum.  相似文献   
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Vitamin A or its synthetic analogues are potent in controlling cell differentiation and in preventing epithelial cancer in experimental animals. Although some community-based studies have found that high serum retinol levels in prediagnostic sera were associated with reduced risk for cancer, other reports in humans have not confirmed this finding. This study is to evaluate the preoperative serum vitamin A level in breast cancer patients in Taiwan. The serum specimens were collected from 106 female cases of breast cancer (aged 30 to 70 years), 32 female cases of benign breast disease (aged 29 to 57 years), and 40 healthy females (aged 22 to 52 years). The serum vitamin A levels were measured by colorimetic analysis. The results showed the mean value of the vitamin A level was 140.4 +/- 65.7 micrograms/dl in the breast cancer group comparing to 145.2 +/- 44.2 micrograms/dl in the benign breast disease group, 144.0 +/- 30.0 micrograms/dl in the control group (P > 0.05). The characteristics of the breast cancer group were analyzed and they revealed that serum vitamin A levels did not bear statistically significant differences in age, duration, steroid receptor, tumor size and menopausal state. (P > 0.05) In conclusion, the serum vitamin A levels were not decreased in early breast cancer patients. The serum vitamin A levels were significantly decreased in the metastatic breast cancer group, especially in liver metastatic women. (P < 0.05). Postoperative vitamin A supplement may have potential benefit to metastatic breast cancer patients.  相似文献   
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The alterations of the ATP concentration in response to fuel secretagogues such as glucose, glyceraldehyde, and ketoisocaproate (KIC) were investigated in a single islet. The intraislet ATP concentration was transiently elevated and then decreased to a level slightly higher than basal. To asses the ATP content under conditions of reduced ATP consumption, the Na-K pump blocker ouabain was used. The elevation of ATP concentration was found unexpectedly to be suppressed under ouabain in the islet, even when incubated with any of the secretagogues. High glucose did not elevate the intracellular creatine phosphate during incubation with ouabain. Since the suppression rate for the intraislet ATP elevation was considerably smaller with KIC than with glyceraldehyde and glucose, we conclude that ouabain inhibits ATP production, at least in part, in the glycolytic pathway through a feedback mechanism.  相似文献   
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