期刊文献+
共找到1,295篇文章
< 1 2 65 >
每页显示 20 50 100
Vitamin A regulates mitochondrial biogenesis and function through p38 MAPK‑PGC‑1α signaling pathway and alters the muscle fiber composition of sheep
1
作者 Pengkang Song Jiamin Zhao +5 位作者 Fanqinyu Li Xiaoyi Zhao Jinxin Feng Yuan Su Bo Wang Junxing Zhao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期898-910,共13页
Background Vitamin A(VA)and its metabolite,retinoic acid(RA),are of great interest for their wide range of physiological functions.However,the regulatory contribution of VA to mitochondrial and muscle fiber compositio... Background Vitamin A(VA)and its metabolite,retinoic acid(RA),are of great interest for their wide range of physiological functions.However,the regulatory contribution of VA to mitochondrial and muscle fiber composition in sheep has not been reported.Method Lambs were injected with 0(control)or 7,500 IU VA palmitate into the biceps femoris muscle on d 2 after birth.At the age of 3 and 32 weeks,longissimus dorsi(LD)muscle samples were obtained to explore the effect of VA on myofiber type composition.In vitro,we investigated the effects of RA on myofiber type composition and intrinsic mechanisms.Results The proportion of type I myofiber was greatly increased in VA-treated sheep in LD muscle at harvest.VA greatly promoted mitochondrial biogenesis and function in LD muscle of sheep.Further exploration revealed that VA elevated PGC-1αmRNA and protein contents,and enhanced the level of p38 MAPK phosphorylation in LD muscle of sheep.In addition,the number of type I myofibers with RA treatment was significantly increased,and type IIx myofibers was significantly decreased in primary myoblasts.Consistent with in vivo experiment,RA significantly improved mitochondrial biogenesis and function in primary myoblasts of sheep.We then used si-PGC-1αto inhibit PGC-1αexpression and found that si-PGC-1αsignificantly abrogated RA-induced the formation of type I myofibers,mitochondrial biogenesis,MitoTracker staining intensity,UQCRC1 and ATP5A1 expression,SDH activity,and enhanced the level of type IIx muscle fibers.These data suggested that RA improved mitochondrial biogenesis and function by promoting PGC-1αexpression,and increased type I myofibers.In order to prove that the effect of RA on the level of PGC-1αis caused by p38 MAPK signaling,we inhibited the p38 MAPK signaling using a p38 MAPK inhibitor,which significantly reduced RA-induced PGC-1αand MyHC I levels.Conclusion VA promoted PGC-1αexpression through the p38 MAPK signaling pathway,improved mitochondrial biogenesis,and altered the composition of muscle fiber type. 展开更多
关键词 MITOCHONDRIa Muscle fiber type PGC-1Α p38 MaPK Retinoic acid vitamin a
下载PDF
Association of plasma vitamin A level with type 2 diabetes mellitus:a community aging population-based cross-sectional study
2
作者 Pengfei Li Jingjing Xu +7 位作者 Yujie Guo Xiaojun Ma Shaobo Zhou Chi Zhang Huiyan Yu Ying Wang Xixiang Wang Linhong Yuan 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2079-2089,共11页
Recent studies indicated that vitamin A(VA)might be involved in the pathology of type 2 diabetes mellitus(T2DM).This cross-sectional study was conducted to explore the association between circulating VA level and T2DM... Recent studies indicated that vitamin A(VA)might be involved in the pathology of type 2 diabetes mellitus(T2DM).This cross-sectional study was conducted to explore the association between circulating VA level and T2DM.A total of 1818 subjects aged 50 years old and above were recruited from the community.Binomial logistic regression and restricted cubic spline(RCS)were applied to analyze the association of plasma VA level with the risk of T2DM.Serum VA and lipid-adjusted VA levels of T2DM patients were significantly higher than that of non-T2DM subjects(P<0.05).The ratios of plasma VA/total cholesterol(TC),VA/high-density lipoprotein cholesterol(HDL-c)and VA/low-density lipoprotein cholesterol(LDL-c)were positively associated with the risk of T2DM in the aging population(P<0.05).Compared with the Q1 level,subjects with Q2 to Q3 levels of plasma VA/triglyceride(TG)have decreased risk of T2DM(odds ratio(OR)Q2=0.68,P_(Q2)=0.021;ORQ3=0.59,P_(Q3)<0.01).Our results indicated that the imbalance of circulating lipids and VA might affect the relationship between VA and T2DM.The middle and aging subjects with higher ratios of plasma VA/TC,VA/HDL-c,and VA/LDL-c displayed increased risk for T2DM,but the moderate ratio of VA/TG might protect against risk of T2DM. 展开更多
关键词 Type 2 diabetes mellitus vitamin a LIPID NUTRITION Disease prevention
下载PDF
Network pharmacology-based approach for exploring the biotargets and mechanisms of vitamin A for the treatment of diabetic foot ulcers
3
作者 Xiaowei Wan Qiuhai Qin +2 位作者 Ruitang Xie Xin Li Min Su 《Frigid Zone Medicine》 2023年第3期186-192,共7页
Background:In some developing countries,people have little knowledge about the causes of diabetic foot ulcers.Therefore,public health education for patients on these conditions is a prerequisite for effective pharmaco... Background:In some developing countries,people have little knowledge about the causes of diabetic foot ulcers.Therefore,public health education for patients on these conditions is a prerequisite for effective pharmacological treatment.Diabetic foot ulcers are a complex symptom of diabetes and are hard to cure due to the lack of efficacious medicine and alternative treatment approaches.Vitamin A(VA)is known to have potent biological functions,including skin repair and immunoregulation.However,the potential pharmacological effects and molecular mechanisms of VA on foot ulcers are still to be discovered.Methods:By using bioinformatic/computational analyses,including network pharmacology,gene ontology and the Kyoto Encyclopedia of Genes and Genomes enrichment analysis,we aimed to identify and reveal the pharmacological targets,molecular mechanisms,biological functions,and signaling pathways of VA in the treatment of diabetic foot ulcers.Results:A total of 66 intersection genes were identified as candidate targets of VA,which are related to diabetic foot ulcers.Therein,18 core genes/targets,namely JUN,MAPK1,THRB,MAPK14,MTNR1B,CXCR3,ESR1,AR,HDAC1,IL-10,CNR1,DRD2,EGFR,ADRA2A,CCND1,RXRB,RARA,and RXRA,were further identified.Furthermore,the biological processes,cell components,and molecular functions which may underlie the effects of VA against diabetic foot ulcers were characterized.Conclusion:Based on our findings,we concluded that the pharmacological effects of VA on diabetic foot ulcers primarily involve the promotion of cellular regeneration and proliferation and the inhibition of inflammatory response.The core genes/targets may potentially serve as promising biomarkers for the diagnosis of diabetic foot ulcers. 展开更多
关键词 diabetic foot ulcers vitamin a network pharmacology core genes MECHaNISMS
下载PDF
Epidemiological Survey on Vitamin A,D,E Levels of Pregnant Women in Baoding
4
作者 Bei Wang Yakun Zhao +4 位作者 Hongli Wu Ling Liang Wenli Kang Yan An Jie Cui 《Journal of Clinical and Nursing Research》 2023年第4期57-62,共6页
Objective:To understand the vitamin levels in pregnant women and its influencing factors and provide a basis for formulating scientific and reasonable vitamin supplement plans for pregnant women.Methods:Pregnant women... Objective:To understand the vitamin levels in pregnant women and its influencing factors and provide a basis for formulating scientific and reasonable vitamin supplement plans for pregnant women.Methods:Pregnant women with a pregnancy period of 12 weeks to 36 weeks in Baoding area were selected as the research subjects using the random sampling method.The sample size is estimated to be 5,000 people,and the diversity of the research subjects,such as age,education level,pregnancy,etc.,were recorded through a survey.The content of the survey included the personal information of the research subjects,pregnancy conditions,eating habits,vitamin supplements taken,etc.At the same time,blood tests were carried out on the research subjects to detect indicators such as vitamin levels.Results:The results of serum measurement showed that the vitamin A level of pregnant women was 0.38±0.12 mg/L,the vitamin E level was 13.51±3.17 mg/L,and the vitamin D level was 17.82±4.18 ng/L;the level of vitamin A of pregnant women in the first trimester was significantly lower than those in the second and third trimesters,and the level of vitamin E of pregnant women in second trimester was significantly higher than those in the first and third trimesters,with statistically significant differences(P<0.05).The rate of vitamin A deficiency in the early stage was significantly higher than that in the middle and late stages of pregnancy,(P<0.05);vitamin D deficiency existed in all pregnant women.Conclusion:Pregnant women should maintain a reasonable diet and eat more vitamin-rich foods,such as vegetables,fruits,etc.;besides,pregnant women should take vitamin supplements under the guidance of doctors or professionals according to their own conditions;moreover,the publicity and education for pregnant women should be improved with more emphasis on vitamin supplementation. 展开更多
关键词 vitaminS Pregnant women EPIDEMIOLOGY
下载PDF
Vitamin A对人宫颈癌细胞抑制作用及其机制的研究 被引量:2
5
作者 韩晓红 邵世和 +1 位作者 薛延军 段秀杰 《江苏科技大学学报(自然科学版)》 CAS 北大核心 2008年第6期72-76,共5页
为研究Vitamin A对人宫颈癌细胞的抑制作用并探讨其作用机制,通过集落形成和裸鼠致瘤实验探讨Vitamin A对人宫颈癌细胞增殖的影响;用电子显微镜、流式细胞仪和细胞DNA琼脂糖凝胶电泳法分析Vitamin A诱导宫颈癌细胞凋亡的细胞特征、生... 为研究Vitamin A对人宫颈癌细胞的抑制作用并探讨其作用机制,通过集落形成和裸鼠致瘤实验探讨Vitamin A对人宫颈癌细胞增殖的影响;用电子显微镜、流式细胞仪和细胞DNA琼脂糖凝胶电泳法分析Vitamin A诱导宫颈癌细胞凋亡的细胞特征、生物化学特征及凋亡细胞百分率.结果表明:Vitamin A对人宫颈癌细胞集落形成有明显抑制作用(P〈0.01),并可抑制人宫颈癌细胞对裸鼠的致瘤作用(P〈0.01);电镜下可见细胞固缩,核膜扭曲,核染色体聚集成块并靠近核膜等凋亡细胞特征;细胞DNA被降解,在琼脂糖凝胶电泳中呈现典型的“阶梯状”图谱;流式细胞仪检测结果显示二倍体核型的特征,在DNA直方图上,G1峰左侧出现亚二倍体细胞群的峰型;凋亡百分率结果显示Vitamin A浓度在大于等于4μg/ml时可诱导人宫颈癌细胞凋亡,且在4~8μg/ml间呈时间和浓度依赖性.由此得出Vitamin A可抑制人宫颈癌细胞增殖,其机理之一是诱导该细胞凋亡,且呈时间和浓度依赖性. 展开更多
关键词 vitamin a HELa细胞 细胞凋亡
下载PDF
Vitamin A regulates intramuscular adipose tissue and muscle development:promoting high-quality beef production 被引量:6
6
作者 Dong Qiao Peng Stephen B.Smith Hong Gu Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期1138-1147,共10页
During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results o... During growth in cattle,the development of intramuscular adipose tissue and muscle is dependent upon cell hyperplasia(increased number of adipocytes)and hypertrophy(increased size of adipocytes).Based on the results of previous studies,other adipose tissue depots(e.g.,perirenal and subcutaneous)develop from the fetal stage primarily as brown adipose tissue.The hyperplastic stage of intramuscular adipose is considered to develop from late pregnancy,but there is no evidence indicating that intramuscular adipose tissue develops initially as brown adipose tissue.Hyperplastic growth of intramuscular adipose continues well into postweaning and is dependent on the timing of the transition to grain-based diets;thereafter,the late-stage development of intramuscular adipose tissue is dominated by hypertrophy.For muscle development,hyperplasia of myoblasts lasts from early(following development of somites in the embryo)to middle pregnancy,after which growth of muscle is the result of hypertrophy of myofibers.Vitamin A is a fat-soluble compound that is required for the normal immunologic function,vision,cellular proliferation,and differentiation.Here we review the roles of vitamin A in intramuscular adipose tissue and muscle development in cattle.Vitamin A regulates both hyperplasia and hypertrophy in in vitro experiments.Vitamin A supplementation at the early stage and restriction at fattening stage generate opposite effects in the beef cattle.Appropriate vitamin A supplementation and restriction strategy increase intramuscular adipose tissue development(i.e.,marbling or intramuscular fat)in some in vivo trials.Besides,hyperplasia and hypertrophy of myoblasts/myotubes were affected by vitamin A treatment in in vitro trials.Additionally,some studies reported an interaction between the alcohol dehydrogenase-1C(ADH1C)genotype and vitamin A feed restriction for the development of marbling and/or intramuscular adipose tissue,which was dependent on the timing and level of vitamin A restriction.Therefore,the feed strategy of vitamin A has the visible impact on the marbling and muscle development in the cattle,which will be helpful to promote the quality of the beef. 展开更多
关键词 adipose tissue CaTTLE Intramuscular adipose tissue Muscle development vitamin a
下载PDF
Study on the Morphology,Particle Size and Thermal Properties of Vitamin A Microencapsulated by Starch Octenylsucciniate 被引量:5
7
作者 XIE Yan-li ZHOU Hui-ming +2 位作者 LIANG Xin-hong HE Bao-shan HAN Xiao-xian 《Agricultural Sciences in China》 CSCD 2010年第7期1058-1064,共7页
The morphology,particle size distribution and thermal properties of microcapsules were evaluated by scanning electron microscopy(SEM),laser diffraction particle size analyzer and differential scanning calorimetry(... The morphology,particle size distribution and thermal properties of microcapsules were evaluated by scanning electron microscopy(SEM),laser diffraction particle size analyzer and differential scanning calorimetry(DSC).Vitamin A was used as model core material,HI-CAP 100(starch octenylsucciniate,OSA-starch) was used as wall material and prepared by spray drying.When emulsions were prepared with 40%(w/v) solution of total solids concentration at the core/wall material ratios of 40%(w/w),the microencapsulation efficiency(ME) was(96.38 ± 0.71)%.Microcapsules exhibited spherical shapes with characteristic dents as evidence by SEM.With the vibrating frequency of the centrifugal granulation from 40,35,30,25 to 20 Hz,the volume diameter(D4,3) was 66.58,71.44,85.61,94.08,and 153.45 μm,respectively.Differential scanning calorimetry(DSC) results revealed that the glass transition temperature(Tg) and melting temperature(Tm) were 56.355 and 208.300°C,respectively.Vitamin A microcapsules produced with HI-CAP 100 exhibited spherical shapes with characteristic dents,which was attributed to drying and cooling solidification involved during spray-drying.The vibrating frequency of the centrifugal granulation had effect on the particle size distribution of microcapsules(P 〈 0.05).The storage and heating stability of microcapsules was well by thermal properties. 展开更多
关键词 vitamin a HI-CaP 100 MICROCaPSULE MORPHOLOGY particle size distribution thermal properties
下载PDF
High prevalence of vitamin A deficiency in Crohn's disease patients according to serum retinol levels and the relative dose-response test 被引量:4
8
作者 Márcia Soares-Mota Tianny A Silva +6 位作者 Luanda M Gomes Marco AS Pinto Laura MC Mendon?a Maria Lúcia F Farias Tiago Nunes Andrea Ramalho Cyrla Zaltman 《World Journal of Gastroenterology》 SCIE CAS 2015年第5期1614-1620,共7页
AIM:To assess the vitamin A status of patients with Crohn's disease(CD) by evaluating serum retinol levels and the relative dose response(RDR) test(liver retinol stores).METHODS:Vitamin A nutritional status was me... AIM:To assess the vitamin A status of patients with Crohn's disease(CD) by evaluating serum retinol levels and the relative dose response(RDR) test(liver retinol stores).METHODS:Vitamin A nutritional status was measured by serum retinol obtained by high performance liquid chromatography and the RDR test for evaluation of the hepatic stores.Body composition was performed by densitometry by dual-energy X-ray absorptiometry.Vitamin A dietary intake was assessed from a semiquantitative food frequency questionnaire.RESULTS:This study included 38 CD patients and 33 controls.Low serum retinol concentrations were detected in 29% of CD patients vs 15% in controls(P < 0.005).The RDR test was positive in 37% of CD patients vs 12% in controls,which indicated inadequate hepatic vitamin A stores(P < 0.005).Individuals with hypovitaminosis A had lower BMI and body fat compared with those without this deficiency.There was no association between vitamin A deficiency and its dietary intake,ileal location,presence of disease activity and prior bowel resections.CONCLUSION:Patients with CD have higher prevalence of vitamin A deficiency,as assessed by two independent methods. 展开更多
关键词 Crohn's disease vitamin a Serum retinol Relative dose response test Body composition
下载PDF
Effects of dietary vitamin A on antioxidant responses of abalone Haliotis discus hannai Ino 被引量:2
9
作者 FU Jinghua ZHANG Wenbing MAI Kangsen FENG Xiuni XU Wei LIUFU Zhiguo TAN Beiping 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第5期141-150,共10页
A 240 d growth experiment was conducted in a re-circulated water system to investigate the effects of dietary vitamin A on growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of j... A 240 d growth experiment was conducted in a re-circulated water system to investigate the effects of dietary vitamin A on growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of juvenile abalone [ initial mass was (0.96±0. 02) g, shell length was (17.70±0.06) mm] were fed to satiation one of three send-purified diets containing 0, 1×10^3, 1×10^6 IU vitamin A per kilogram diet, respectively. Results showed that the daily increment in shell length (DISL) of abalone in the treatment with 1 × 10^3 IU vitamin A per kilogram diet was significantly higher than that with 0 or 1 × 10^6 IU vitamin A per kilogram supplementation (P 〈 0.05). Vitamin A deficiency (0 IU/kg) significantly elevated the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) in the viscera of abalone (P 〈 0.05). In muscle, the effects of vitamin A deficiency on SOD and GPX activities were the same as those in viscera, however, the activity of GR significantly decreased (P 〈 0.05). Vitamin A deficiency significantly decreased the ratio of CAT to SOD (eatalase/superoxide dismutase) in viscera (P 〈 0.05). Nevertheless, it significantly decreased the ratio of GR to GPX in muscle (P 〈 0.05). Compared with the supplement of 1 x 103 IU vitamin A per kilogram, excessive vitamin A ( 1 × 106 IU/kg) had no significant effects on the activities of CAT, SOD and glutathione-S-transferase (GST) (P 〉 0.05), but significantly elevated GPX and GR activities in viscera (P 〈 0. 05). In muscle, the activities of CAT, SOD, GPX, GST and GR were significantly decreased by the excessive dietary vitamin A supplement (P 〈 0.05). Compared with the supplement of 1×10^3 IU vitamin A per kilogram, vitamin A-excessive had no significant effect on the value of ratio of CAT to SOD either in viscera or in muscle ( P 〉0.05 ). The ratio of GR to GPX was significantly decreased in viscera, but significantly elevated in muscle in the vitamin A-excessive group (P 〈 0.05 ). In conclusion, optimum supplement of vitamin A ( 1 × 103 IU/kg) was beneficial for abalone to maintain maximum growth and antioxidant system. Hypoor hyper-vitaminosis A would decrease growth and the efficiency of scavenging reactive oxygen species (ROS) of abalone. 展开更多
关键词 Haliotis discus hannai vitamin a antioxidant enzymes MOLLUSK
下载PDF
The Effect of Vitamin A on Secretion of IFN-γ and IL-4 in A549 Cells Induced by Mycoplasma Pneumoniae 被引量:2
10
作者 吴小兰 刘先洲 汤纪路 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第6期649-652,共4页
In order to investigate the effect of vitamin A (VA) on the secretion of IFN-γ and IL-4 in Mycoplasma Pneumoniae (MP)-induced A549 cells, A549 cells were co-cultured with MP for different time lengths and then th... In order to investigate the effect of vitamin A (VA) on the secretion of IFN-γ and IL-4 in Mycoplasma Pneumoniae (MP)-induced A549 cells, A549 cells were co-cultured with MP for different time lengths and then the levels of IFN-γ and IL-4 in the cell culture supernatants were detected before and after treatment with different concentrations of VA by using the enzyme-linked immu-nosorbent assay ( ELISA). The results showed that the level of IFN-γ and IL-4 in the supernatants of MP-induced A549 cells was much higher than that in non-induced cells (P〈0.01). After application of VA, IL-4 level was not increased until the concentration of VA was up to 0.5×10-5 mol/L (P〈0.01). However, with concentration of VA increased up to 1×10-4 mol/L, IL-4 was significantly suppressed (P〈0.01). It was concluded that MP could induce the secretion of IFN-γ and IL-4 in A549 cells. VA could inhibit the secretion of IFN-γ and increase the IL-4 level in MP-induced A549 cells. However, high concentration of VA had an inhibitory effect on the secretion of IL-4 as well as on the IFN-γ. These data provided a theoretical basis for the application of VA in MP pneumonia in the clinical practice. 展开更多
关键词 Mycoplasma pneumoniae vitamin a IFN-Γ IL-4
下载PDF
The Role of Vitamin A in Iron Deficiency Anemia and Implications for Interventions 被引量:3
11
作者 DARWIN KARYADI AND MARTIN W. BLOEM(Semeo/Tropmed Community Nutrition Center, University of Indonesia,Jalan Salemba Raya 6, Jakarta 10430, Indonesia: Helen Keller International/Indonesia, P.O. Box 4338, Jakarta, Indonesia) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1996年第2期316-324,共9页
This presentation will describe the various reports on the interdependence of vitamin A and Fe
关键词 The Role of vitamin a in Iron Deficiency anemia and Implications for Interventions
下载PDF
Variability in Vitamin A Intake of Pregnant Women in Ngaoundere-Cameroon with Geographic Origin, Socio-Professional and Demographic Factors 被引量:1
12
作者 Edith N. Fombang Wilfred Damndja Ngaha Richard Aba Ejoh 《Food and Nutrition Sciences》 2016年第2期74-82,共9页
Variability in vitamin A (VA) intake of pregnant women in Ngaoundere town according to geographic origin, socio-professional and demographic factors was studied. A total of 100 pregnant women attending ante natal visi... Variability in vitamin A (VA) intake of pregnant women in Ngaoundere town according to geographic origin, socio-professional and demographic factors was studied. A total of 100 pregnant women attending ante natal visits at the Regional Hospital in Ngaoundere were involved in the survey. A questionnaire was used to obtain information on geographic origin, socio-professional status, birth history, demographic and anthropometric factors. Dietary intake was assessed using 24-hour dietary recall. Meals potentially rich in VA consumed by these women were collected, their carotenoids contents quantified and VA activity determined by conversion. Results indicated that daily VA intake of these women varied significantly (p < 0.05) with geographic origin, level of education and age of pregnancy. VA intake of pregnant women of Northern origin (Adamawa, North and Far North Regions) was significantly (p < 0.05) lower (496 μg/day/woman) than that of women of Southern origin (588 μg/day/woman), although both were below the recommended intake of 800 μg/day/woman. The more educated a woman and the older her pregnancy, the higher her VA intake. VA consumption of pregnant women of Northern origin was significantly influenced by their age, whereas for pregnant women of Southern origin, BMI (Body Mass Index) equally had a significant influence on their VA intake. Socio-professional status, marital status and number of children did not significantly influence the daily VA intake of these women. Thus, a pregnant woman originating from the Northern part of the country and having no formal education, consumed less foods rich in carotenoids and therefore was more at risk for vitamin A deficiency. 展开更多
关键词 Pregnant Women Geographic Origin Socio-Demographic Factors Ngaoundere vitamin a Intake
下载PDF
用正交设计实验优选Vitamin AD微囊制备工艺
13
作者 姚新成 许玉华 +1 位作者 庄太能 吕博 《石河子大学学报(自然科学版)》 CAS 2004年第3期257-258,共2页
以明胶、阿拉伯树胶为囊材,用复凝聚法制备维生素AD微囊,运用正交设计实验优选其制备工艺。结果表明:复凝聚法制备微囊制备工艺中加酸速度是影响其质量的主要因素,方差分析P<0.05。利用优选的工艺制备的微囊质量稳定,能达到设计的要求。
关键词 正交设计 vitamin aD 复凝聚法 微囊
下载PDF
中国裕固族、东乡族311例7~12岁儿童Vitamin A水平对比分析
14
作者 王睿 尤媛 +2 位作者 杜旦 张印红 王玉 《广东微量元素科学》 CAS 2010年第7期19-23,共5页
为了解裕固族和东乡族7~12岁儿童vitaminA水平差异,按照整群分层抽样方法分别抽取裕固族民族聚居区(甘肃省肃南裕固族自治县)和东乡族民族聚居区(甘肃省东乡族自治县)7-12岁儿童184例和127例作为研究对象,采用微量荧光测定法检... 为了解裕固族和东乡族7~12岁儿童vitaminA水平差异,按照整群分层抽样方法分别抽取裕固族民族聚居区(甘肃省肃南裕固族自治县)和东乡族民族聚居区(甘肃省东乡族自治县)7-12岁儿童184例和127例作为研究对象,采用微量荧光测定法检测血清中vitaminA含量。结果表明,裕固族儿童血清vitaminA平均水平为1.44μmol/L,无vitaminA缺乏(VAD)患者,中度亚临床VAD(SVAD)患病率为10.87%(20/184),可疑SVAD患病率为16.85%(31/184);东乡族儿童血清vitaminA平均水平为1.29p~mol/L,VAD患病率为3.94%(5/127),SVAD患病率14.96%(19/127),可疑SYAD患病率为18.11%(23/127);两民族间儿童血清vitaminA水平有差异;不同年龄组儿童血清vitaminA状况构成比差异有统计学意义,不同民族的男性儿童vitaminA水平间有差异,男女儿童SVAD和可疑SVAD上无明显差异。结论是两民族学龄儿童较多的还是存在SVAD及可疑SVAD现象,患SVAD及可疑SVAD的儿童应该是今后vitaminA缺乏防治的主要对象。 展开更多
关键词 血清vitamin a 裕固族 东乡族 儿童 缺乏
下载PDF
Synergistic Effect of Zinc and Vitamin A on T Cell Functions
15
作者 TING-XIN LI YUN LI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第2期131-134,共4页
Objective To determine whether supplementation of zinc and vitamin A may improve the function of T cells in human PBMC. Methods T cells were separated and cultured in vitro, supplemented with either Zn or vitamin A al... Objective To determine whether supplementation of zinc and vitamin A may improve the function of T cells in human PBMC. Methods T cells were separated and cultured in vitro, supplemented with either Zn or vitamin A alone, or both Zn and vitamin A (10^-6 mol/L, 10^-5 mol/L, 10^-4 mol/L). After harvesting, cell proliferation, cell cycle, apoptosis, expression or function of cell-surface molecules, such as CD^3+, CD^4+, and CD^8+ were detected. Results Higher proliferation level and lower apoptosis level were observed in cells supplemented with both Zn and vitaminA, showing the strongest effect (P〈0.05). Zn-supplement increased the CD^4+/CD^3+ cell percentage, and simultaneously decreased the CD^8+/CD^3+ cell population. VA-supplement showed the opposite effect in comparison with Zn-supplement. Conclusion T-cell function can be improved depending on the zinc and/or vitamin A supplemented. 展开更多
关键词 vitamin a supplementation Zinc supplementation T cell IMMUNITY
下载PDF
Effects of temperature,moisture and choline chloride on vitamin A stability in broiler premix
16
作者 SUN Haixia SHAN Anshan SHI Baoming 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期115-119,共5页
A 2×2×2 factorial design was adopted to study the effects of temperature, moisture and choline chloride on vitamin A stability in premix. The results indicated that temperature, moisture and choline chloride... A 2×2×2 factorial design was adopted to study the effects of temperature, moisture and choline chloride on vitamin A stability in premix. The results indicated that temperature, moisture and choline chloride damaged vitamin A significantly. The regression equations of vitamin A disappearance rate and storage time were as follows: in room temperature (18±3)℃, y=14.368Ln(x)+ 4.1425, R^2=0.978; in high temperature (4 ℃ ), y=22.24Ln (x)+13.27, R^2=0.9918; in low moisture (2%-3%), y= 10.408Ln (x)+9.5418, R^2=-0.9322; in high moisture (8%-9%), y=26.199Ln(x)+7.8741, R^2=-0.9949; in the condition of choline chloride flee, y=9.5125Ln(x)+ 8.9869, R^2=0.9826; supplemented with choline chloride, y=27.094Ln (x)+8.4276, R^2=0.9984. Temperature had highly significant interaction with moisure and choline chloride on destruction of vitamin A, respectively from the periods of two months storage. However, from the period of the first month storage, the interaction of moisture and choline chloride, as well as the interaction of temperature, moisture and choline destroyed vitamin A remarkably. 展开更多
关键词 vitamin a TEMPERaTURE MOISTURE choline chloride STaBILITY
下载PDF
Roles of vitamin A in the regulation of fatty acid synthesis
17
作者 Fu-Chen Yang Feng Xu +1 位作者 Tian-Nan Wang Guo-Xun Chen 《World Journal of Clinical Cases》 SCIE 2021年第18期4506-4519,共14页
Dietary macronutrients and micronutrients play important roles in human health.On the other hand,the excessive energy derived from food is stored in the form of triacylglycerol.A variety of dietary and hormonal factor... Dietary macronutrients and micronutrients play important roles in human health.On the other hand,the excessive energy derived from food is stored in the form of triacylglycerol.A variety of dietary and hormonal factors affect this process through the regulation of the activities and expression levels of those key player enzymes involved in fatty acid biosynthesis such as acetyl-CoA carboxylase,fatty acid synthase,fatty acid elongases,and desaturases.As a micronutrient,vitamin A is essential for the health of humans.Recently,vitamin A has been shown to play a role in the regulation of glucose and lipid metabolism.This review summarizes recent research progresses about the roles of vitamin A in fatty acid synthesis.It focuses on the effects of vitamin A on the activities and expression levels of mRNA and proteins of key enzymes for fatty acid synthesis in vitro and in vivo.It appears that vitamin A status and its signaling pathway regulate the expression levels of enzymes involved in fatty acid synthesis.Future research directions are also discussed. 展开更多
关键词 vitamin a acetyl-Coa carboxylase Fatty acid synthase Fatty acid elongase Stearoyl-Coa desaturase Fatty acid synthesis
下载PDF
Night blindness due to vitamin A deficiency associated with resected adenocarcinoma of the pancreas
18
作者 Andreas Kontos Hamzeh Kayhanian +1 位作者 Fatima El-Khouly Roopinder Gillmore 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第1期206-207,共2页
【正】Dear Sir,W e write to present a rare case of night blindness caused by vitamin A deficiency secondary to resected adenocarcinoma of the pancreas.To our knowledge this is the first reported case of this associati... 【正】Dear Sir,W e write to present a rare case of night blindness caused by vitamin A deficiency secondary to resected adenocarcinoma of the pancreas.To our knowledge this is the first reported case of this association.A 62 year-old man presented to the eye clinic with a 12mo history of worsening nyctalopia and colour perception. 展开更多
关键词 ERG Night blindness due to vitamin a deficiency associated with resected adenocarcinoma of the pancreas
下载PDF
Vitamin A,Vitamin E,Lutein and β-Carotene in Lung Tissues from Subjects with Chronic Obstructive Pulmonary Disease and Emphysema
19
作者 Michael W.Schaffer Somdutta Sinha Roy +1 位作者 Shyamali Mukherjee Salil K.Das 《Open Journal of Respiratory Diseases》 2013年第2期44-51,共8页
Vitamin A (VA) and its active metabolites play an essential role in lung airway function. Patients with moderate to severe chronic obstructive pulmonary disease (COPD) have a lower serum retinol concentration, and imp... Vitamin A (VA) and its active metabolites play an essential role in lung airway function. Patients with moderate to severe chronic obstructive pulmonary disease (COPD) have a lower serum retinol concentration, and improvement of their 1-second Forced Expiratory Volume (FEV1) is achieved with VA supplementation. In order to test our hypothesis that the VA signaling pathway is compromised in COPD, we obtained 20 lung samples from COPD patients differing in the degree of emphysema as judged by their FEV% values. All were smokers or were exposed to secondhand smoke. Levels of VA (retinol/retinyl ester), tocopherols and carotenoids (lutein, beta-carotene) in these samples were determined using HPLC. Additional analytes beside VA were included for their known roles as antioxidants and modulators of VA-action. VA levels (retinol/retinyl ester) decreased significantly with the increase in severity of emphysema. Among other analytes, α-tocopherol levels fell by 25.8% in the severe emphysema group in comparison to the mild emphysema group, and lutein levels similarly decreased in severe compared to moderate emphysema groups. However, beta-carotene levels remained unchanged. Thus there is a significant linear correlation between lung VA-levels and the severity of emphysema. There was also a significant reduction in the levels of α-, δ-tocopherol and lutein in the severe emphysema group of COPD patients who either smoked or were exposed to smoke. 展开更多
关键词 COPD Β-CaROTENE EMPHYSEMa LUTEIN vitamin a vitamin E HPLC
下载PDF
The Role of Copper and Vitamin A Deficiencies Leading to Neurological Signs in Captive Cheetahs(Acinonyx jubatus)and Lions(Panthera leo)in the United Arab Emirates
20
作者 Claudia Kaiser Ulrich Wernery +2 位作者 Jorg Kinne Laurie Marker Annette Liesegang 《Food and Nutrition Sciences》 2014年第20期1978-1990,共13页
Neurological signs like ataxia and hind limb paresis have often been reported in cheetahs (Acinonyx jubatus), lions (Panthera leo) and snow leopards (Panthera unica). As a cause, copper and Vitamin A deficiencies have... Neurological signs like ataxia and hind limb paresis have often been reported in cheetahs (Acinonyx jubatus), lions (Panthera leo) and snow leopards (Panthera unica). As a cause, copper and Vitamin A deficiencies have been discussed. Many cases were seen in cheetahs and lions in the United Arab Emirates (UAE) within the last years. The aim of this study was to find correlations between nutrition, serum, and tissue levels, focusing on copper and Vitamin A. Blood and tissue samples of affected and unaffected animals were analyzed at the Central Veterinary Research Laboratory in Dubai, UAE. Animals were split into three different groups (A, B and C) according to their diets. Minerals were determined in serum, tissue, food and water samples, and serum was additionally analyzed for Vitamin A and E. Liver, kidney and spinal cord samples were taken for histopathological investigations. Mean serum copper and liver copper levels of animals fed pure chicken muscle meat without supplements were significantly lower (0.41 ± 0.71 μM/L;2.16 ± 0.95 ppm wet weight) than in animals fed a whole carcass prey diet (12.16 ± 3.42 μM/L;16.01 ± 17.51 ppm wet weight) (p < 0.05). Serum Vitamin A and E levels were highest in animals fed whole carcass prey diets (1.85 ± 0.68;27.31 ± 5.69 μM/L). Liver zinc concentrations were highest in animals fed pure chicken meat only (43.75 ± 16.48 ppm wet weight). In histopathology, demyelination of the spinal cord was found in all of the affected animals and most commonly when fed a diet based on poultry without supplements. 展开更多
关键词 aTaXIa Cheetah(acinonyx jubatus) COPPER Lion(Panthera leo) vitamin a
下载PDF
上一页 1 2 65 下一页 到第
使用帮助 返回顶部