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931.
天然甜味剂罗汉果的研究与应用 总被引:12,自引:2,他引:10
本文综述了广西特产药用植物罗汉果的化学成分和药理研究,其甜味成分的甜度与结构关系及提取分离方法和应用。 相似文献
932.
Selection of an extracellular esterase-producing microorganism 总被引:2,自引:0,他引:2
Guillermo R. Castro Adrián O. Stettler Marcela A. Ferrero Faustino Siñeriz 《Journal of industrial microbiology & biotechnology》1992,10(3-4):165-168
Summary The conventional esterase plate-screening technique has been modified in order to obtain a better differentiation of high producing strains. A short exposure to Lugol's iodine solution after colony growth enhanced the contrast between the precipitation halo and the background. Batch cultures of a selected strain characterized as belonging to theBacillus subtilis group showed a high level of extracellular activity at pH 6.6 to 8.0 and 35°C. In crude extracts the optimum enzymatic activity was obtained at 35°C and pH 7.0. 相似文献
933.
Thin‐Film Solar Cells: Atomic‐Scale Observation of Oxygen Substitution and Its Correlation with Hole‐Transport Barriers in Cu2ZnSnSe4 Thin‐Film Solar Cells (Adv. Energy Mater. 6/2016)
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934.
A Layer‐Structured Electrode Material Reformed by a PO4‐O2 Hybrid Framework toward Enhanced Lithium Storage and Stability
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The surface framework of LiCoO2 is modified through a surface treatment called phosphidation, which suppressed the unwanted phase transition occurring above 4.2 V. The surface instability of LiCoO2 toward organic electrolytes is simultaneously improved by changing its surface structure from an O2‐based framework to a PO4‐based framework that can protect against HF attack during cycling. Phosphidated LiCoO2 is successfully synthesized that showed greater stability in its bulk and surface structures. The phosphidated form enables faster Li+ diffusion and prevents irreversible phase transitions, especially when charged above 4.2 V, and consequently demonstrates excellent cycling performance and rate capabilities. The improved kinetics and stability resulting from phosphidation make LiCoO2 highly suitable as a high‐voltage cathode material for use in lithium ion batteries. 相似文献
935.
Young Hoon Oh Gyeong Tae Eom Kyoung Hee Kang Jeong Chan Joo Young-Ah Jang Jae Woo Choi Bong Keun Song Seung Hwan Lee Si Jae Park 《Bioprocess and biosystems engineering》2016,39(4):555-563
Gene-expression cassettes for the construction of recombinant Clostridium beijerinckii were developed as potential tools for metabolic engineering of C. beijerinckii. Gene expression cassettes containing ColE1 origin and pAMB origin along with the erythromycin resistance gene were constructed, in which promoters from Escherichia coli, Lactococcus lactis, Ralstonia eutropha, C. acetobutylicum, and C. beijerinckii are examined as potential promoters in C. beijerinckii. Zymogram analysis of the cell extracts and comparison of lipase activities of the recombinant C. beijerinckii strains expressing Pseudomonas fluorescens tliA gene suggested that the tliA gene was functionally expressed by all the examined promoters with different expression level. Also, recombinant C. beijerinckii expressing C. beijerinckii secondary alcohol dehydrogenase by the constructed expression cassettes successfully produced 2-propanol from glucose. The best promoter for TliA expression was the R. eutropha phaP promoter while that for 2-propanol production was the putative C. beijerinckii pta promoter. Gene expression cassettes developed in this study may be useful tools for the construction of recombinant C. beijerinckii strains as host strains for the valuable chemicals and fuels from renewable resources. 相似文献
936.
937.
Robert C. Smith Revital Amiaz Tian-Mei Si Lawrence Maayan Hua Jin Sylvia Boules Henry Sershen Chunbo Li Juanjuan Ren Yanhong Liu Mary Youseff Abel Lajtha Alessandro Guidotti Mark Weiser John M. Davis 《PloS one》2016,11(1)
Schizophrenic patients have a high rate of smoking and cognitive deficits which may be related to a decreased number or responsiveness of nicotinic receptors in their brains. Varenicline is a partial nicotinic agonist which is effective as an antismoking drug in cigarette smokers, although concerns have been raised about potential psychiatric side-effects. We conducted a double-blind placebo controlled study in 87 schizophrenic smokers to evaluate the effects of varenicline (2 mg/day) on measures of smoking, cognition, psychiatric symptoms, and side-effects in schizophrenic patients who were cigarette smokers. Varenicline significantly decreased cotinine levels (P<0.001), and other objective and subjective measures of smoking (P < .01), and responses on a smoking urges scale (P = .02), more than placebo. Varenicline did not improve scores on a cognitive battery designed to test the effect of drugs on cognitive performance in schizophrenia (the MATRICS battery), either in overall MATRICS battery Composite or individual Domain scores, more than placebo. There were no significant differences between varenicline vs. placebo effects on total symptom scores on psychiatric rating scales, PANSS, SANS, or Calgary Depression scales, and there were no significant drug effects in any of these scales sub-scores when we used Benjamin-Hochberg corrected significance levels (α = .05). Varenicline patients did not show greater side-effects than placebo treated patients at any time point when controlled for baseline side-effect scores. Our study supports the use of varenicline as a safe drug for smoking reduction in schizophrenia but not as a cognitive enhancer.Trial Registration: ClinicalTrials.gov 00802919 相似文献
938.
Objective
This study aimed to examine the prognostic value of overexpressed p16INK4a in vulvar cancer. Although the tumor suppressor p16INK4a has been shown to be of prognostic value in a wide variety of cancers and precancerous lesions, its role in the vulvar cancer is still unclear.Methods
All publications in English language on the association between p16INK4a and clinicopathological features of vulvar cancer were searched from Pubmed, Embase, and Web of Science, and those in Chinese language were identified manually and online from the China National Knowledge Infrastructure. Strict inclusion and exclusion criteria were followed. Odds ratios(ORs) or risk ratios(RRs) with 95% confidence intervals(CIs) were pooled to assess the strength of association. Publication bias was estimated using funnel plots and the Egger’s regression test.Results
A total of 17 studies with 2309 patients were included. The p16INK4a overexpression was found to correlate significantly with the lower International Federation of Gynecology and Obstetrics stage(I+II vs III+IV; OR = 0.60,95%CI:0.41–0.86,P = 0.006),negative lymph node metastasis(negative vs positive; OR = 0.61,95%CI:0.39–0.95,P = 0.029),patient’s age<55(OR = 0.54,95%CI:0.31–0.96,P = 0.034),human papillomavirus–positive status(OR = 0.01,95%CI:0.00–0.11,P<0.001),and higher overall survival(RR = 0.53,95%CI = 0.35–0.80,P = 0.003).Conclusion
The p16INK4a might be associated with a higher survival and indicates better prognosis of vulvar cancer. 相似文献939.
Si Hyung Lee Seung Woo Kwak Eun Min Kang Gyu Ah Kim Sang Yeop Lee Hyoung Won Bae Gong Je Seong Chan Yun Kim 《PloS one》2016,11(2)