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食品中核苷类成分的药理作用研究进展 被引量:69
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作者 张雪梅 杨丰庆 夏之宁 《食品科学》 EI CAS CSCD 北大核心 2012年第9期277-282,共6页
日常摄入的核苷及核苷酸类成分在维持骨髓造血细胞、肠黏膜以及脑组织的正常功能方面具有重要的作用。而膳食是为人体提供该类成分的主要来源之一。本文综述了膳食中核苷及核苷酸对人体免疫、代谢、肝脏、心血管及神经系统等所发挥的生... 日常摄入的核苷及核苷酸类成分在维持骨髓造血细胞、肠黏膜以及脑组织的正常功能方面具有重要的作用。而膳食是为人体提供该类成分的主要来源之一。本文综述了膳食中核苷及核苷酸对人体免疫、代谢、肝脏、心血管及神经系统等所发挥的生理作用,以及其抗菌和抗病毒等其他生理活性。 展开更多
关键词 食品 核苷 核苷酸 药理作用
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Crop Breeding Chips and Genotyping Platforms: Progress, Challenges, and Perspectives 被引量:51
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作者 Awais Rasheed Yuanfeng Hao +4 位作者 Xianchun Xia Awais Khan Yunbi Xu Rajeev K. Varshney Zh-onghu He 《Molecular Plant》 SCIE CAS CSCD 2017年第8期1047-1064,共18页
There is a rapidly rising trend in the development and application of molecular marker assays for gene map- ping and discovery in field crops and trees. Thus far, more than 50 SNP arrays and 15 different types of geno... There is a rapidly rising trend in the development and application of molecular marker assays for gene map- ping and discovery in field crops and trees. Thus far, more than 50 SNP arrays and 15 different types of genotyping-by-sequencing (GBS) platforms have been developed in over 25 crop species and perennial trees. However, much less effort has been made on developing ultra-high-throughput and cost-effective genotyping platforms for applied breeding programs. In this review, we discuss the scientific bottlenecks in existing SNP arrays and GBS technologies and the strategies to develop targeted platforms for crop mo- lecular breeding. We propose that future practical breeding platforms should adopt automated genotyping technologies, either array or sequencing based, target functional polymorphisms underpinning economic traits, and provide desirable prediction accuracy for quantitative traits, with universal applications under wide genetic backgrounds in crops. The development of such platforms faces serious challenges at both the technological level due to cost ineffectiveness, and the knowledge level due to large genotype- phenotype gaps in crop plants. It is expected that such genotyping platforms will be achieved in the next ten years in major crops in consideration of (a) rapid development in gene discovery of important traits, (b) deepened understanding of quantitative traits through new analytical models and population designs, (c) integration of multi-layer -omics data leading to identification of genes and pathways responsible for important breeding traits, and (d) improvement in cost effectiveness of large-scale genotyping. Crop breeding chips and genotyping platforms will provide unprecedented opportunities to accelerate the development of cultivars with desired yield potential, quality, and enhanced adaptation to mitigate the effects of climate change. 展开更多
关键词 Single nucleotide polymorphisms (SNPs) Genotyping-by-sequencing (GBS) SNP arrays Crop breeding Genotyping platforms
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超高压处理对南美白对虾在冷藏过程中贮藏特性的影响 被引量:42
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作者 常耀光 李兆杰 +1 位作者 薛长湖 张亚琦 《农业工程学报》 EI CAS CSCD 北大核心 2008年第12期230-237,共8页
该文以不同的超高压条件(200,400,600,700MPa)对南美白对虾进行处理,通过考察与比较不同压力处理组冷藏过程中感官、微生物以及各化学指标的变化情况,揭示超高压技术对南美白对虾冷藏特性的影响。结果表明:超高压处理可以有效地杀灭南... 该文以不同的超高压条件(200,400,600,700MPa)对南美白对虾进行处理,通过考察与比较不同压力处理组冷藏过程中感官、微生物以及各化学指标的变化情况,揭示超高压技术对南美白对虾冷藏特性的影响。结果表明:超高压处理可以有效地杀灭南美白对虾中绝大多数微生物,抑制贮藏过程中挥发性盐基氮的积累,延缓pH值的变化,从而延长南美白对虾的货架期,且处理压力越高延长效果越显著;超高压处理会给鲜虾带来不同程度上的煮熟虾的风味;400MPa和600MPa处理使虾在冷藏过程的黑变提前,而700MPa处理可以完全抑制南美白对虾黑变现象的发生;超高压能够改变腺苷三磷酸(ATP)及其代谢产物的代谢情况,但不影响腺苷酸(AMP)的代谢途径。因此超高压处理可以改善南美白对虾在冷藏过程中的品质,对南美白对虾冷藏具有潜在的应用价值。 展开更多
关键词 南美白对虾 超高压 冷藏 黑变 核苷酸
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鲜味物质及其在水产调味品中的应用 被引量:40
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作者 何炘 杨荣华 《中国调味品》 CAS 北大核心 2005年第4期3-8,37,共7页
阐述了氨基酸和核苷酸等一些鲜味物质的结构,产生鲜味的机理,列举了部分天然食品中鲜味物质的含量,介绍鲜味物质的呈味特性,生产现状及其应用情况。阐述了氨基酸和核苷酸之间的显著的相乘作用。详细的介绍了水产品中鲜味物质的研究,包... 阐述了氨基酸和核苷酸等一些鲜味物质的结构,产生鲜味的机理,列举了部分天然食品中鲜味物质的含量,介绍鲜味物质的呈味特性,生产现状及其应用情况。阐述了氨基酸和核苷酸之间的显著的相乘作用。详细的介绍了水产品中鲜味物质的研究,包括水产品中鲜味物质的种类,水产品中的味与鲜味的关系,鉴定水产品中特征风味成分的方法,为水产品鲜味调味品的开发利用提供了科学依据。 展开更多
关键词 鲜味 氨基酸 核苷酸 相乘作用 水产品
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日本沼虾冰藏期间ATP降解产物变化及鲜度评价 被引量:35
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作者 戚晓玉 李燕 周培根 《水产学报》 CAS CSCD 北大核心 2001年第5期482-484,共3页
关键词 日本沼虾 核苷酸 鲜度指标值 鲜度评价 冰藏期 ATP降解
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A High-Density SNP Genotyping Array for Rice Biology and Molecular Breeding 被引量:40
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作者 Haodong Chen Weibo Xie +11 位作者 Hang He Huihui Yu Wei Chen Jing Li Renbo Yu Yue Yao Wenhui Zhang Yuqing He Xiaoyan Tang Fasong Zhou Xing Wang Deng Qifa Zhang 《Molecular Plant》 SCIE CAS CSCD 2014年第3期541-553,共13页
A high-density single nucleotide polymorphism (SNP) array is critically important for geneticists and molecu- lar breeders. With the accumulation of huge amounts of genomic re-sequencing data and available technolog... A high-density single nucleotide polymorphism (SNP) array is critically important for geneticists and molecu- lar breeders. With the accumulation of huge amounts of genomic re-sequencing data and available technologies for accurate SNP detection, it is possible to design high-density and high-quality rice SNP arrays. Here we report the devel- opment of a high-density rice SNP array and its utility. SNP probes were designed by screening more than 10 000 000 SNP loci extracted from the re-sequencing data of 801 rice varieties and an array named RiceSNP50 was produced on the Illumina Infinium platform. The array contained 51 478 evenly distributed markers, 68% of which were within genic regions. Several hundred rice plants with parent/F1 relationships were used to generate a high-quality cluster file for accurate SNP calling. Application tests showed that this array had high genotyping accuracy, and could be used for dif- ferent objectives. For example, a core collection of elite rice varieties was clustered with fine resolution. Genome-wide association studies (GWAS) analysis correctly identified a characterized QTL. Further, this array was successfully used for variety verification and trait introgression. As an accurate high-throughput genotyping tool, RiceSNP50 will play an important role in both functional genomics studies and molecular breeding. 展开更多
关键词 single nucleotide polymorphisms (SNPs) ARRAY RICE molecular breeding.
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Hepatocellular carcinoma in nonalcoholic fatty liver: Role of environmental and genetic factors 被引量:39
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作者 Paola Dongiovanni Stefano Romeo Luca Valenti 《World Journal of Gastroenterology》 SCIE CAS 2014年第36期12945-12955,共11页
Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoh... Hepatocellular carcinoma(HCC) is the fourth cause of cancer related mortality, and its incidence is rapidly increasing. Viral hepatitis, alcohol abuse, and exposure to hepatotoxins are major risk factors, but nonalcoholic fatty liver disease(NAFLD) associated with obesity, insulin resistance, and type 2 diabetes, is an increasingly recognized trigger, especially in developed countries. Older age, severity of insulin resistance and diabetes, and iron overload have been reported to predispose to HCC in this context. Remarkably, HCCs have been reported in non-cirrhotic livers in a higher proportion of cases in NAFLD patients than in other etiologies. Inherited factors have also been implicated to explain the different individual susceptibility to develop HCC, and their role seems magnified in fatty liver, where only a minority of affected subjects progresses to cancer. In particular, the common I148 M variant of the PNPLA3 gene influencing hepatic lipid metabolism influences HCC risk independently of its effect on the progression of liver fibrosis. Recently, rare loss-of-function mutations in Apolipoprotein B resulting in very low density lipoproteins hepatic retention and in Telomerase reverse transcriptase influencing cellular senescence have also been linked to HCC in NAFLD. Indeed, hepatic stellate cells senescence has been suggested to bridge tissue aging with alterations of the intestinal microbiota in the pathogenesis of obesity-related HCC. A deeper understanding of the mechanisms mediating hepatic carcinogenesis during insulin resistance, and the identification of its genetic determinants will hopefully provide new diagnostic and therapeutic tools. 展开更多
关键词 Nonalcoholic fatty liver disease STEATOSIS Hepatocellular carcinoma CIRRHOSIS FIBROGENESIS Liver disease Genetics Single nucleotide polymorphism Patatin-like phospholipase domain-containing 3
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虫草有效成分的研究进展 被引量:37
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作者 夏春雨 孙巍 刘学铭 《中国食用菌》 北大核心 2009年第2期3-7,共5页
虫草是一类重要的药用真菌,近年来,研究者对不同种类虫草的化学成分进行了广泛研究。对虫草的化学成分研究进行了总结,主要包括核苷类物质(虫草素、腺苷等)、虫草多糖、D-甘露醇、甾醇、超氧化物歧化酶及氨基酸等。
关键词 虫草 化学成分 核苷类物质 虫草多糖 虫草酸 甾醇 超氧化物歧化酶 氨基酸
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啤酒废酵母中酵母抽提物的制备 被引量:25
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作者 陈洁 王璋 肖刚 《无锡轻工大学学报(食品与生物技术)》 CSCD 北大核心 2001年第4期356-362,共7页
主要研究了机械破壁、pH值以及麦芽根核酸酶的作用对啤酒酵母自溶过程的影响 .均质破壁能显著提高自溶速率及酵母抽提物中蛋白质和核苷酸的含量 ,麦芽根核酸酶的加入有效地提高了酵母抽提物中 5′ 核苷酸含量 ,而提高自溶时的 pH值不能... 主要研究了机械破壁、pH值以及麦芽根核酸酶的作用对啤酒酵母自溶过程的影响 .均质破壁能显著提高自溶速率及酵母抽提物中蛋白质和核苷酸的含量 ,麦芽根核酸酶的加入有效地提高了酵母抽提物中 5′ 核苷酸含量 ,而提高自溶时的 pH值不能显著地提高酵母抽提物中 5′ 核苷酸的含量 .因此 ,有效地提高酵母抽提物中 5′ 核苷酸含量的方法是 :啤酒废酵母经 0 .5%NaHCO3脱苦后 ,加 2倍体积无菌水和 5%NaCl,再加质量分数为 1%的核酸酶 ,搅拌均匀 ,在 4 0MPa下均质 3次 ,然后升温至 55℃ ,自溶 30h ,得到的酵母抽提物中 5′ GMP含量高达 6.37mg/g . 展开更多
关键词 酵母抽提物 自溶 核苷酸 啤酒废酵母
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Efficacy of intramuscular BCG polysaccharide nucleotide on mild to moderate bronchial asthma accompanied with allergic rhinitis: a randomized, double blind, placebo-controlled study 被引量:26
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作者 LI Jing LUO Ding-fen LI Sui-ying SUN Bao-qing ZHONG Nan-shan 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第19期1595-1603,共9页
Background Atopy is a state of allergy to common antigens and is founded on an immune disturbance of exuberant Th2 activity and IgE production. There is also epidemiologieal and experimental evidence that exposure to ... Background Atopy is a state of allergy to common antigens and is founded on an immune disturbance of exuberant Th2 activity and IgE production. There is also epidemiologieal and experimental evidence that exposure to myeobacteria has the potential to suppress the development of asthma or atopy. Since Thl and Th2 immune mechanisms are significantly antagonistic, it is hypothesized that myeobaeterial exposure may moderate atopie disease by modification of immune responses. Methods One hundred and twenty mild to moderate persistent asthmatics accompanied with allergic rhinitis were randomly divided into four groups with one injection every other day for 18 times for group A with 1 ml of normal saline, B with 0.5 mg of Bacillus Calmette-Guérin polysaccharide nucleotide (BCG-PSN) and C with 1 mg of BCG-PSN, 36 times for group D with 0. 5 mg of BCG-PSN. Markers for the severity of asthma and rhinitis including the amount of inhaled corticosteriod, bronchodilator and oral H1 blocker-loratidine being used to obtain optimal symptomatic control, symptom scores of asthma and allergic rhinitis, peak expiratory flow (PEF), histamine provocative dose that produces at least a 20% change in forced expiratory volume with in 1 second (PD20-FEV1 ), blood IgE levels as well as dermatophagoides pteronysinus (DP) and dermatophagoides farinae (DF) skin prick test were measured every visit for 6 months. Results There were no differences for symptom scores of asthma, daily use of bronchodilator, PEF, PD20- FEV1, blood IgE as well as DF and DP skin prick test among the four groups. Score for allergic rhinitis decreased significantly in groups B, C and D on day 36 and 72 as compared with group A ( P 〈 0.05 ). Score for allergic rhinitis increased after day 72 in group B and C while it was significantly lower in group D ( P 〈 0.05 ). The patients in group D used less amount of inhaled beclomethosone than other groups ( P 〈 0.05 ) from day 72 after the treatment to day 180. Oral loratadine consumption i 展开更多
关键词 asthma allergic rhinitis Bacillus Calmette-Guérin polysaccharide nucleotide
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外源核苷酸对断奶仔猪生产性能和小肠发育的影响 被引量:25
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作者 张永青 王龙生 陈安国 《中国畜牧杂志》 CAS 北大核心 2007年第21期19-21,共3页
选用21日龄断奶仔猪160头,随机分为5组,每组4个重复。对照组饲喂基础日粮,试验组饲喂含0.2%核苷酸的日粮。经21d试验,结果表明:日粮中添加0.2%核苷酸能显著提高断奶仔猪的饲料利用率,饲料转化率比对照组提高16.90%(P<0.05),并能显著... 选用21日龄断奶仔猪160头,随机分为5组,每组4个重复。对照组饲喂基础日粮,试验组饲喂含0.2%核苷酸的日粮。经21d试验,结果表明:日粮中添加0.2%核苷酸能显著提高断奶仔猪的饲料利用率,饲料转化率比对照组提高16.90%(P<0.05),并能显著提高仔猪断奶后第7天十二指肠绒毛高度和第14天回肠黏膜DNA含量,分别比对照组提高44.79%(P<0.05)和111.65%(P<0.05)。 展开更多
关键词 核苷酸 小肠黏膜 DNA 断奶仔猪
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盐水鸭工业化加工过程中主要滋味物质的测定及呈味作用评价 被引量:28
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作者 陶正清 刘登勇 +1 位作者 周光宏 徐幸莲 《核农学报》 CAS CSCD 北大核心 2014年第4期632-639,共8页
本文采用高效液相色谱和氨基酸自动分析仪测定了工业化加工过程中盐水鸭中核苷酸及其降解产物以及游离氨基酸含量的变化,并采用滋味活性值和等鲜浓度来评价上述滋味物质的呈味作用和鲜味强度。结果表明,复卤和煮制工艺对风味核苷酸和游... 本文采用高效液相色谱和氨基酸自动分析仪测定了工业化加工过程中盐水鸭中核苷酸及其降解产物以及游离氨基酸含量的变化,并采用滋味活性值和等鲜浓度来评价上述滋味物质的呈味作用和鲜味强度。结果表明,复卤和煮制工艺对风味核苷酸和游离氨基酸的形成过程影响最为显著。盐水鸭中的核苷酸类物质以5'-肌苷酸(5'-IMP)和肌苷(I)为主,占总量的47.33%;主要的游离氨基酸为Tau(212.37mg·100g-1)、Glu(96.66mg·100g-1)和Ala(95.52mg·100g-1)。5'-IMP和Glu的滋味活性值大于1,对盐水鸭的滋味有重要的贡献。盐水鸭的等鲜浓度为3.89 g MSG·100g-1,说明盐水鸭有强烈的鲜味强度。 展开更多
关键词 盐水鸭 加工工艺 核苷酸 游离氨基酸
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Association of gene polymorphisms of tumour necrosis factor-α and interleukin-13 with chronic obstructive pulmonary disease in Han nationality in Beijing 被引量:23
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作者 JIANGLing HEBei +3 位作者 ZHAOMing-wu NINGLan-ding LIXiao-ying YAOWan-zhen 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第7期541-547,共7页
Background Genetic factors are believed to play a role in the individual susceptibility to chronic obstructive pulmonary disease (COPD). A single nucleotide polymorphism (SNP) of tumour necrosis factor-α (TNF-α) has... Background Genetic factors are believed to play a role in the individual susceptibility to chronic obstructive pulmonary disease (COPD). A single nucleotide polymorphism (SNP) of tumour necrosis factor-α (TNF-α) has been reported but inconsistent results may arise from different populations and phenotypes of COPD. There are only a few published studies of interleukin-13 (IL-13) SNPs on COPD. The SNPs of TNF-α and IL-13 have not been studied in the Chinese population. This research was conducted to study the frequencies of IL-13 gene promoter 1055 (IL-13-1055) and TNF-α gene-308 polymorphisms in the patients with COPD and to investigate the effect of those genetic polymorphisms on COPD in the Chinese population.Methods A cohort of COPD patients and age matched controls were recruited from an inpatient hospital service in Beijing. Venous blood was obtained and genomic DNA was extracted from peripheral blood monocytes using standard method. Genomic DNA was used as a template for amplification by polymerase chain reaction (PCR) to determine the polymorphism at -1055 in the IL-13 gene promoter region. PCR restriction fragment length polymorphism (RFLP) was used to determine polymorphisms in the TNF-α gene-308 position. The products were investigated by sequence analysis also. Results One hundred and eleven COPD patients and 97 controls were studied. Seventy-five cases were current smokers in COPD patients and 36 were current smokers in controls. The frequencies of TT genotype in the IL-13 gene promoter region were 11.7% (13/111) in the COPD group and 13.4% (13/97) in the controls (P=0.713). However, the OR value of TT genotype was significantly increased to 6.4 (95% CI 1.62-25.39) in the smokers with COPD. TT genotype was also positively related to family history of COPD, OR=7.7 (95% CI 1.37-43.80). The frequencies of A allele in the TNF-α gene were 5.9% in COPD and 3.1% in controls (P=0.131). The OR value of A allele was 5.0 (95% CI 1.011 to 25.059) in smokers with COPD. Conclusions There is no significant diff 展开更多
关键词 INTERLEUKIN-13 tumour necrosis factor-α single nucleotide polymorphism chronic obstructive pulmonary disease
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Association between two polymorphisms of the bone morphogenetic protein-2 gene with genetic susceptibility to ossification of the posterior longitudinal ligament of the cervical spine and its severity 被引量:25
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作者 WANG Hao YANG Zhao-hui +3 位作者 LIU Dong-mei WANG Ling MENG Xiang-long TIAN Bao-peng 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第18期1806-1810,共5页
Background Ossification of the posterior longitudinal ligament (OPLL) has a strong genetic background. Previous studies have shown that bone morphogenetic protein-2 (BMP2) and BMP2 mRNA are expressed in ossifying ... Background Ossification of the posterior longitudinal ligament (OPLL) has a strong genetic background. Previous studies have shown that bone morphogenetic protein-2 (BMP2) and BMP2 mRNA are expressed in ossifying matrix and chondrocytes adjacent to cartilaginous areas of OPLL tissues and mesenchymal cells with fibroblastic features in the immediate vicinity of the cartilaginous areas. It is suggested that BMP2 plays different roles in the different stages of development of OPLL. However, it remains unknown which factors induce ligament cells to produce BMP2. Methods OPLL patients (n=-192) and non-OPLL controls (n=304) were studied. Radiographs of the cervical spine were analyzed for extent of OPLL. We investigated whether single nucleotide polymorphisms of exons 3(-726) T/C and 3(-583) NG in the BMP2 gene are statistically associated with genetic susceptibility to OPLL in Chinese Han subjects. Results There was no statistical difference between the occurrence of exons 3(-726) T/C and 3(-583) NG and the occurrence of OPLL in the cervical spine. However, there was a significant association between occurrence of exon 3(-726) T/C polymorphism and occurrence of OPLL in males of cases and controls in the cervical spine. In addition, no significant association was found between the exons 3(-726) T/C and 3(-583) A/G with number of ossified cervical vertebrae in OPLL patients. Conclusions Exon 3(-583) A/G polymorphism in BMP2 gene is not associated with the occurrence and the extent of OPLL in the cervical spine. Chinese Han male patients with TC and CC genotypes in exon 3(-726) T/C have genetic susceptibility to OPLL but not to more extensive OPLL in the cervical spine. 展开更多
关键词 ossification of the posterior longitudinal ligament bone morphogenetic protein-2 single nucleotide polymorphisms case control study
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反相高效液相色谱-串联质谱法测定母乳及奶粉中核苷和核苷酸的含量 被引量:26
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作者 张婷婷 曾明飞 +1 位作者 金燕 刘绿叶 《分析化学》 SCIE EI CAS CSCD 北大核心 2014年第4期585-591,共7页
建立了反相高效液相色谱-串联质谱法测定母乳和婴幼儿奶粉中5种核苷和5种核苷酸含量的方法.样品经温水溶解后,选择0.5%乙酸沉淀蛋白,并用超滤离心管离心过滤大分子物质;采用键合较长碳链的Acclaim C30色谱柱为分析柱,以20 mmol/L醋酸... 建立了反相高效液相色谱-串联质谱法测定母乳和婴幼儿奶粉中5种核苷和5种核苷酸含量的方法.样品经温水溶解后,选择0.5%乙酸沉淀蛋白,并用超滤离心管离心过滤大分子物质;采用键合较长碳链的Acclaim C30色谱柱为分析柱,以20 mmol/L醋酸铵和乙腈为流动相,梯度洗脱分离,流速0.4 mL/min,温度15℃,紫外检测波长260 nm,采用电喷雾正离子模式进行电离,选择反应监测模式进行检测,外标法定量分析.结果表明,核苷和核苷酸在12 min内达到基线分离,在0.02~ 100 mg/L范围内,线性关系好,相关系数R>0.999,方法检出限0.1 ~0.2 ng,其中CMP,UMP,GMP,U,AMP在1,10和50 mg/L加标水平下的平均回收率在85.2%~ 104.7%之间,峰面积RSD在0.7%~2.0%之间(n=6),核苷C,I,G,A和核苷酸IMP在0.5,5和10 mg/L加标水平下的平均回收率在85.08%~ 103.7%之间,峰面积RSD在0.6%~1.7%之间(n=6).应用本方法定性和定量分析母乳和婴幼儿奶粉中核苷和核苷酸的含量,并且对紫外和质谱测定的结果进行比较,基本一致. 展开更多
关键词 液相色谱 质谱 核苷 核苷酸 母乳 奶粉
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肌苷酸和肌苷作为评价虾鲜度质量指标的研究 被引量:23
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作者 李燕 周培根 戚晓玉 《上海水产大学学报》 CSCD 2002年第3期264-267,共4页
测定了不同温度保藏期间罗氏沼虾肌肉组织中ATP及其降解产物含量的变化 ,并对其鲜度进行感官评定。结果表明肌苷酸和次黄嘌呤的含量与感官评定的结果之间有良好的相关性 ;IMP含量在保藏中有一积累过程 ,达最高值后逐渐下降 ;当感官评定... 测定了不同温度保藏期间罗氏沼虾肌肉组织中ATP及其降解产物含量的变化 ,并对其鲜度进行感官评定。结果表明肌苷酸和次黄嘌呤的含量与感官评定的结果之间有良好的相关性 ;IMP含量在保藏中有一积累过程 ,达最高值后逐渐下降 ;当感官评定结果表明沼虾已不可食用时 ,Hx的含量达 0 .70 μmol/g以上 ;Hx可作为评定冷藏期间沼虾质量的一个指标。 展开更多
关键词 肌苷酸 肌苷 鲜度 质量指标 罗氏沼虾 感官评定 肌肉组织 冷藏 冷黄嘌呤
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不同烹调方式对羊肉品质的影响 被引量:25
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作者 任国艳 曹利 +6 位作者 王玉琴 郭金英 宋娅 康怀彬 崔国庭 吴影 韩树羽 《食品科学》 EI CAS CSCD 北大核心 2016年第19期24-30,共7页
研究不同烹调方式(蒸煮、烘烤和煎炸)对羊肉品质的影响,分别对样品中氨基酸、脂肪酸和核苷酸的组成及含量、质构指标以及肌肉微观结构进行检测。结果表明:蒸煮方式的损失率最低,对氨基酸、脂肪酸和核苷酸的组成及含量的影响最小;在3种... 研究不同烹调方式(蒸煮、烘烤和煎炸)对羊肉品质的影响,分别对样品中氨基酸、脂肪酸和核苷酸的组成及含量、质构指标以及肌肉微观结构进行检测。结果表明:蒸煮方式的损失率最低,对氨基酸、脂肪酸和核苷酸的组成及含量的影响最小;在3种烹调方式对肉样处理过程中,肉样的氨基酸模式和脂肪酸模式均发生不同程度的变化;煎炸肉样中呈味氨基酸含量为55.33%,显著高于蒸煮肉样呈味氨基酸含量(50.67%)和烘烤肉样呈味氨基酸含量(49.33%);烘烤肉样呈味核苷酸含量最低;蒸煮、煎炸和烘烤对肉样的脂肪酸组成及含量虽有影响,但组间并无差异显著性。烘烤肉样咀嚼性优于煎炸肉样和蒸煮肉样。在3种烹调方式处理过程中,烘烤肉样肌纤维束变形、肌束膜破坏、肌间脂肪受损程度最严重。 展开更多
关键词 羊肉 烹调方式 氨基酸 脂肪酸 核苷酸 扫描电子显微镜
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酵母提取物的研究 被引量:23
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作者 张虹 张宏 毕丽君 《中国调味品》 CAS 北大核心 2000年第2期20-23,共4页
本文介绍酵母提取物—一种天然调味料的生产工艺及营养和鲜味成分的分析。酵母提取物的生产以啤酒酵母为原料,经过滤、脱异味、酵母自溶等工艺制得。酵母提取物中的十八种氨基酸和呈味物质核苷酸,分别用高效液相色谱进行分析。
关键词 酵母提取物 氨基酸 核苷酸 高效液相色谱 调味料
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Single nucleotide polymorphism C677T in the methylenetetrahydrofolate reductase gene might be a genetic risk factor for infertility for Chinese men with azoospermia or severe oligozoospermia 被引量:21
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作者 Zhou-Cun A Yuan Yang +2 位作者 Si-Zhong Zhang Na Li Wei Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第1期57-62,共6页
Aim: To analyze the distribution of the single nucleotide polymorphism (SNP) C677T in the methylenetetrahydrofolate reductase (MTHFR) gene in 355 infertile Chinese patients with idiopathic azoospermia or severe o... Aim: To analyze the distribution of the single nucleotide polymorphism (SNP) C677T in the methylenetetrahydrofolate reductase (MTHFR) gene in 355 infertile Chinese patients with idiopathic azoospermia or severe oligozoospermia and 252 fertile Chinese men as controls to explore the possible association of the SNP and male infertility. Methods: Using the polymerase chain reaction (PCR)-restriction fragment length polymorphism technique, the allele and genotype distribution of SNP C677T in the MTHFR gene were investigated in both patients and controls. Results: The frequencies of allele T (40.9% vs 30.4%, P = 0.002, odds ration [OR] = 1.58, 95% confidence interval [CI]: 1.24-2.02) and mutant homozygote (TT) (18.3% vs. 11.5%, P = 0.023, OR = 1.72, 95% CI: 1.07-2.76) as well as carrier with allele (TT + CT) (63.4% vs. 49.2%, P = 0.0005, OR = 1.79, 95% CI: 1.29-2.48) in infertile patients were significantly higher than those in controls. After patient stratification, the significant differences in distribution of the SNP between each patient subgroup and control group still remained. Conclusion: Our findings indicate that there is an association of SNP C677T in the MTHFR gene with male infertility, suggesting that this polymorphism might be a genetic risk factor for male infertility in Chinese men. 展开更多
关键词 male infertility methylenetetrahydrofolate reductase gene single nucleotide polymorphism C677T
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酵母抽提物的功能及在食品中的应用 被引量:16
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作者 董家武 杨子忠 《食品科技》 CAS 北大核心 2003年第6期25-27,共3页
介绍了酵母抽提物的国际标准、生产工艺流程、功能及作用原理和在食品中的具体应用。
关键词 酵母抽提物 氨基酸 核苷酸
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