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“1＋1＋1”人才培养模式作为校企合作办学的一个尝试,以其可行性强且兼顾理论与实践一体化的优势,近年来得到很多职业学校的推崇。本文结合我校烹饪专业成功实施此模式的例子,就“1＋1＋1”人才培养模式应用于中职烹饪教育时在实际发展过程中的关键问题进行探讨与研究。 相似文献
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本文建立了一类描述H1N1型流行病的常微分方程模型,利用常微分方程动力系统的理论,研究了我们所建立的模型,得出了该系统的奇点以及奇点的类型,并做了相图,并且得出结论,在H1N1流感的控制中,政府行为是最重要的元素. 相似文献
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图书管理服务中人员流动量很大，甲型H1N1流感主要通过飞沫和媒介接触传播，图书管理员是预防甲型H1H1流感的重点人群。本文阐述了图书馆员在流通服务工作中预防甲型H1N1流感应该注意的问题，图书管理员参与公共活动应该要注意的事项，为创造安全健康的图书管理服务提供参考。 相似文献
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参照DPE制备的方法,在这里以溴代萘为原料制备格氏试剂1-苯基-1-萘基-1-乙醇,再将1-苯基-1-萘基-1-乙醇进行脱水反应生成1-苯基-1-萘基乙烯（NPE）。利用核磁、红外等手段鉴定其结构。 相似文献
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以硫酰氯对苯基丙酮进行氯代反应得到1-氯苯基丙酮，直接与苯进行Friedel-Crafts反应得到1，1-二苯基丙酮，总收率71．6％。 相似文献
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蔡聪明 《大科技．科学之谜》2003,(12):27-28
打开初中的数学教科书,我们可以看到质数的定义:一个大于1的整数,如果除了1和它自己之外,再也没有其它的因子,这个整数就叫做质数。因此,质数(又叫做素数)就是2、3、5、7、11…,其中2是唯一的偶质数。高中的数学教科书,也是采用同样的定义。两者都有“排除掉1”的条款,即规定1不是质数。但是,似乎很少有人想过:为什么要有“排1条款”?或者更基本的问题:为什么会出现这个定义?如果将“自然数的集合”与“大自然”互相对照,那么“质数”(不可分解)就相当于“原子”(本义是不可分割)。古希腊哲学家的原子论认为:万物都是原子组成的,原子永恒不… 相似文献
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Chatterjee S Dhar S Sengupta B Ghosh A De M Roy S Chakrabarti S 《Indian journal of clinical biochemistry : IJCB》2010,25(3):260-272
Polycyclic aromatic hydrocarbons of tobacco require activation by phase I enzymes, such as cytochrome-P4501A1 (CYP1A1) to
become an ultimate carcinogen, which are subjected to detoxification by phase II enzymes, especially glutathione S-transferases (GSTs). A study was designed to find whether genetic predisposition are risk modifiers of oral pathologies.
The study included 102 cases with Oral Cancers (OCs), 68 cases with nonmalignant pathologies, 100 cases as control group.
GSTM1 null genotype was associated with increased risk of OCs but not with benign pathologies. Deleted GSTT1 was associated
with all pathologies. Both m1m2 and m2m2 polymorphisms of CYP1A1 were associated with oral pathologies. 相似文献
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BackgroundQuizalofop-p-ethyl (QPE), a unitary R configuration aromatic oxyphenoxypropionic acid ester (AOPP) herbicide, was widely used and had led to detrimental environmental effects. For finding the QPE-degrading bacteria and promoting the biodegradation of QPE, a series of studies were carried out.ResultsA QPE-degrading bacterial strain YC-XJ1 was isolated from desert soil and identified as Methylobacterium populi, which could degrade QPE with methanol by cometabolism. Ninety-seven percent of QPE (50 mg/L) could be degraded within 72 h under optimum biodegradation condition of 35°C and pH 8.0. The maximum degradation rate of QPE was 1.4 mg/L/h, and the strain YC-XJ1 exhibited some certain salinity tolerance. Two novel metabolites, 2-hydroxy-6-chloroquinoxaline and quinoxaline, were found by high-performance liquid chromatography/mass spectroscopy analysis. The metabolic pathway of QPE was predicted. The catalytic efficiency of strain YC-XJ1 toward different AOPPs herbicides in descending order was as follows: haloxyfop-p-methyl ≈ diclofop-methyl ≈ fluazifop-p-butyl > clodinafop-propargyl > cyhalofop-butyl > quizalofop-p-ethyl > fenoxaprop-p-ethyl > propaquizafop > quizalofop-p-tefuryl. The genome of strain YC-XJ1 was sequenced using a combination of PacBio RS II and Illumina platforms. According to the annotation result, one α/β hydrolase gene was selected and named qpeh1, for which QPE-degrading function has obtained validation. Based on the phylogenetic analysis and multiple sequence alignment with other QPE-degrading esterases reported previously, the QPEH1 was clustered with esterase family V.ConclusionM. populi YC-XJ1 could degrade QPE with a novel pathway, and the qpeh1 gene was identified as one of QPE-degrading esterase gene.How to cite: Li X, Wang J, Wu W, et al. Co-metabolic biodegradation of quizalofop-p-ethyl by Methylobacterium populi YC-XJ1 and identification of QPEH1 esterase. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.05.003. 相似文献
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文章就西藏地区小儿甲流流行特征及诊疗经验作一阐述,同时提出了医疗机构如何应对和防控甲流疫情。 相似文献
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Sadegh Fattahi Mohammad Karimi Alivije Farhang Babamahmoodi Masomeh Bayani Mahmoud Sadeghi Haddad Zavareh Mohsen Asouri Maryam Lotfi Galia Amirbozorgi Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(4):467-472
Hepatitis B virus (HBV) infection is a worldwide health concern which is associated with significant morbidity and mortality. Both viral and host factors have a significant effect on infection, replication and pathogenesis of HBV. The aim of this study was to investigate the effect of CYP2E1 and CYP1A1 genetic variants on susceptibility to HBV. 143 individuals including 54 chronic HBV patients and 89 healthy controls were enrolled in the genotyping procedure. rs2031920 and rs3813867 at CYP2E1 as well as rs4646421 and rs2198843 at CYP1A1 loci were studied in all subjects using PCR–RFLP (restriction fragment length polymorphism) analysis. Both variants at CYP2E1 locus were monomorphic in all studied subjects. Genotype frequency of rs4646421 was significantly different between chronic HBV patients and healthy blood donors (P = 0.04, OR 4.31; 95% CI 1.04–17.7). Furthermore, individuals carrying at least one C allele (CC or CT genotypes) for rs4646421 seemed to have a decrease risk of hepatitis in comparison with TT genotype (P = 0.039). Our results showed a relationship between rs4646421 TT genotype (rare genotype) and the risk for developing chronic HBV infection (four times higher). Further studies are needed to examine the role of CYP1A1 polymorphism in susceptibility to chronic HBV infection. 相似文献
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