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1.
Nitric oxide (NO) is a simple ubiquitous signaling molecule and plays important roles in almost every biological system. Recent evidences suggest that NO may act as an endocrine molecule. The aim of this review is considering available literature on endocrine roles of NO and/or its metabolites, i.e. nitrite and nitrate. Existing data suggest the idea that NO is a hormone that after production in tissues, it is stabilized and transported as nitrite and/or S-nitrosothiols in the blood to target cells.  相似文献   

2.

Background  

The central circadian pacemaker is a remarkably robust regulator of daily rhythmic variations of cardiovascular, endocrine, and neural physiology. Environmental lighting conditions are powerful modulators of circadian rhythms, but regulation of circadian rhythms by disease states is less clear. Here, we examine the effect of ischemic stroke on circadian rhythms in rats using high-resolution pineal microdialysis.  相似文献   

3.
就巢性是家禽性成熟的标志,大多数家禽都具有就巢性,特别是一些优良地方品种,如文昌鸡、丝羽乌骨鸡、矮脚鸡等。而就巢性又会明显影响产蛋性能,就巢性机理的研究对提高家禽的产蛋性能具有重要意义,因此,本文主要从家禽的就巢行为学研究、内分泌调控机理及其分子机制进行探讨。  相似文献   

4.
咖啡碱的生理功能及其作用机制   总被引:4,自引:1,他引:3  
咖啡碱是世界上消费最广泛的精神类药物及日常饮食成分之一,对机体的神经、内分泌、呼吸和心血管等系统均有复杂的影响,而且咖啡碱还具有抗癌效果。此外,摄入咖啡碱会增加骨质疏松和流产的风险。本文就近年来咖啡碱的生理功能及其作用机制等的相关研究作一简要综述。  相似文献   

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Obesity subjects individuals into metabolic and endocrine disorders. Thus obesity may increase the risk of vitamin D deficiency. This text aims at studying the prevalence of vitamin D deficiency and secondary hyperparathyroidism in obese children. In a non-randomized case control study on 52 obese children (body mass index (BMI) >95th percentile) aged 4 to 16 years undertaken at the outpatient endocrine clinic of the Children Hospital at Tabriz University between 2009-2011. This study was conducted to compare the prevalence of vitamin D deficiency and secondary hyperparathyroidism in obese children compared with 57 non obese (BMI < 85th percentile). 109 children including 52 (50.5%) boys and 57 (49.5%) girls were studied. Most of case (76.9%) and control (42.1%) groups suffered from degrees of vitamin D deficiency. There was meaningful statistical difference between two groups considering to vitamin D deficiency and parathyroid hormone (p = 0.001). A negative relations was found between iPTH and vit D level (p < 0.001, r = -0.2), BMI and 25-OH vit D (p < 0.001, r = -0.2). A positive relation was observed between parathyroid hormone and BMI (p = 0.009, r = 0.1). Obese children are at high risk at vitamin D deficiency and secondary hyperparathyroidism. BMI appears to be an important risk factor for vitamin D deficiency.  相似文献   

7.
Traditional medical science has kept the mind separate from the body. Recently people realize the effect of mind on health and psychoneuroimmunology is the new evolved science that describes the interactions between psyche and soma. In this review through a typical psycho-neuro-endocrino-immune network the effects of psychological stress (acute, brief naturalistic and chronic) and relaxation on immune modulation has been shown. From this network Corticotrophin Releasing Factor (CRF), Adrenocorticotrophic Hormone (ACTH), Glucocorticoids (GC), alpha-endorphin and Met-enkephalin are found as important endocrine components and T cells, B cells, monocytes/macrophages, Natural Killer (NK) cells and their cytokines that is Tumor Necrosis Factor-alpha (TNF-alpha), Interferon Gamma (IFN-alpha) and interleukins such as IL-1, IL-2, IL-4, IL-6, IL-10, IL-12 etc. are found as important immune components. Finally, it has been shown that, acute, brief naturalistic and chronic stress have different immune modulatory activities which are harmful to one's homeostasis and relaxation can help to maintain that homeostasis.  相似文献   

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Diabetes mellitus is one of the most wide spread endocrine disorders and an important developing health problem in the world. Cardiovascular disease is a common complication of type 2 diabetes. Several risk factors for coronary heart disease cosegregate in type 2 diabetes, including hyperglycemia, hyperlipaemia, increases production of free radical and decrease in antioxidant defense system. In this study we evaluated the effect of vitamin C supplementation on fasting and postprandial oxidative stress and lipid profile in type 2 diabetic patients. 30 patients with type 2 diabetes from Nader Kazemi Clinic, Shiraz, Iran were randomly divided into 2 groups; vitamin C treatment group (1000 mg d(-1)) and placebo group from May to September 2010. Fasting and postprandial lipid profile and Malondialdehyde (MDA) level were measured at the beginning of the study and after six weeks of supplementation. Data analysis was carried out using Mann-Whitney U test with p < 0.05 being significant by SPSS software version 16.The result of the study showed a significantly decrease in fasting (p = 0.006) and postprandial MDA (p < 0.001) in vitamin C group compare to placebo group but not in lipid profile. This study suggests that vitamin C supplementation can decrease fasting and postprandial oxidative stress and may prevent diabetes complication.  相似文献   

11.
3   总被引:3,自引:0,他引:3  
以籼稻栽培品种秋桂矮11的愈伤组织为材料,对铜元素的作用作了进一步的研究。在含有2,4-D和脯氨酸的培养基中添加铜元素对愈伤组织的增殖量影响极小,但转移到再分化培养基后这些愈伤组织能再生出显著更多的植株。另一方面,在含有BA、NAA和脯氨酸的培养基中添加铜元素则会由于添加量的不同而产生显著的促进或抑制愈伤组织增殖的作用。然而,不论是增殖受过铜的促进的或者是抑制的愈伤组织,均能在再分化培养基上再生出数量更多和质量更好的植株。  相似文献   

12.
陈年镛  夏品蒲  高璐 《中国稻米》2014,(1):103-103,105
金农3优3号是福建农林大学作物科学学院用金农3A为母本、金恢3号为父本杂交组配而成的籼型三系杂交稻,是福建省2012年审定的杂交红米新品种。该品种糙米红褐色,具有优质、高产、生育期适中等优点。  相似文献   

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The narrow limits which are set by the ethics in medicine and the possibilities of interference by the subjective burden of the volunteers for investigations with man, compel to particularly complicated experimental designs. In principle it is aspired to measure isolated individual nutrients, interference with other ingredients of foodstuffs and disturbances of body functions by food components, for which the results from animal experiments serve as an orientation for the expected effects. Deficiency experiments that were mainly used in the past are seldomly carried out today, since longterm one-sided diets are necessary for which volunteers cannot be found easily for professional and private reasons. Similar difficulties are encountered with longterm nutrient balance experiments for absorption and retention studies of nutrients which are subject to endocrine regulation mechanisms, like calcium, iron or protein-nitrogen. Biochemical parameters for the minimum requirements of essential nutrients are increasingly available with growing sensitivity. They allow among other things an early recognition of interferences with food components. The use of biokinetic methods allows quantitative statements about the absorption of nutrients and combinations of nutrients, about the size of the turnover and at least as a point of departure about some known quantities of the gastrointestinal tract motoricity. Loads with low doses of radioactive substances which could supply precise data, are permitted with man in the FRG only in medicine. Animal experiments provide models for biokinetic considerations. A comparison of the parameters allows also quantitative conclusions from analogy for man with a more dependable basis as the usual reference quantity. An interdisciplinary cooperation in this field could promote research in nutrition and toxicology considerably.  相似文献   

15.
Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes’ activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents.  相似文献   

16.
陕西小麦Glu-A3和Glu-B3位点等位变异的检测和分析   总被引:1,自引:1,他引:0  
低分子量谷蛋白亚基(LMW-GS)与小麦品质密切相关。为了给陕西小麦的品质改良提供参考依据,采用STS分子标记,检测了175份陕西小麦品种(系)Glu-A3和Glu-B3位点的等位变异组成。结果表明,陕西小麦Glu-A3位点存在4种等位变异,即Glu-A3a、Glu-A3b、Glu-A3c和Glu-A3d,分别占12.6%、1.7%、58.3%和27.4%;Glu-B3位点存在8种等位变异,即Glu-B3a、Glu-B3b、Glu-B3d、Glu-B3e、Glu-B3f、Glu-B3g、Glu-B3i和Glu-B3j,分别占4.6%、2.9%、45.7%、0.6%、2.9%、8.5%、4.0%和30.8%。在陕西不同地区小麦之间,两个位点等位变异的种类、组合及其分布比例存在差异,这可能与地区间不同的自然地理环境、饮食习惯、育种目标及亲本选择有关。  相似文献   

17.
RNA silencing is a sequence-specific RNA degradation system that is conserved in a wide range of organisms. The elucidation of the mechanism of RNA silencing has stimulated its use as a reverse genetics tool, because RNA silencing strongly down-regulates the expression of the target gene in a sequence-specific manner. The major protein fraction of wheat grain is gluten which is largely responsible for the functional properties of dough. Gliadins contribute mainly to the extensibility and viscosity of gluten and dough, with the polymeric glutenins being responsible for elasticity. The aim of this work was therefore to silence the expression of specific γ-gliadins by RNA interference, to demonstrate the feasibility of systematically silencing specific groups of gluten proteins. The sequence of a γ-gliadin gene was used to construct the pghp8.1 plasmid. The hpRNA silencing fragment was designed on the basis of 169 base pairs (bp) in sense and antisense orientation with the sequence of the Ubi1 intron as spacer region between the repeats. Two lines of bread wheat were transformed by particle bombardment. Gliadins were extracted from 30 mg of flour, separated by acid-PAGE and determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Seven transgenic lines were obtained and all of them showed reduced levels of γ-gliadins. All seven transgenic plants were fully fertile and their grain morphology and seed weight were comparable to the control lines. MALDI-TOF MS showed that six peaks, present in the untransformed line, were missing in transgenic lines of the BW208 genotype whereas three peaks were missing in the BW2003 genotypes. The proportion of γ-gliadins was reduced, by about 55–80% in the BW208 lines and by about 33–43% in the BW2003 lines. The ELISA assay based on the R5 antibody showed reductions in total gliadins (μg/mg flour) in three of the BW208 lines and in one BW2003 line, but an increase in one BW208 line (C613).  相似文献   

18.
黄烷酮3-羟化酶(flavanone 3-hydroxylase,F3H)是黄酮类化合物合成途径中的一个关键酶。本研究基于前期转录组数据,以‘福菜薯7-6’叶片为材料成功克隆CDS序列长度为1107 bp的基因IbF3H,利用生物信息学分析甘薯F3H基因的序列特征、氨基酸序列对比、蛋白系统进化树、蛋白的二、三级结构、预测其跨膜结构和亚细胞定位,并利用qRT-PCR分析盐旱胁迫处理下基因的表达特性。结果表明,该基因含有3个外显子和2个内含子,编码368个氨基酸,蛋白分子量为41.12 kDa,等电点为5.83。存在多种类型的启动子顺式作用元件,如光响应元件G-Box、ACE,干旱胁迫相关的MBS元件,与脱落酸激素响应相关的ABRE元件等。与其他植物的氨基酸序列相似性达到了80%以上,可见IbF3H的编码区高度保守,且黄烷酮3-羟化酶在进化上具有较高的保守性。IbF3H蛋白含有非血红素双加氧酶结构域(DIOX-N superfamily)和典型的F3H蛋白功能结构域(2OG-FeⅡ-Oxy加氧酶结构域),属于双加氧酶超家族。IbF3H蛋白可能在细胞质中表达并且不具备跨膜结构。qRT-PCR研究结果表明,IbF3H基因并非组织特异性表达的基因,叶和茎表达量高于茎尖和根。模拟盐胁迫处理后,IbF3H基因表达量呈现先下降后上升的趋势;模拟干旱胁迫处理后,IbF3H基因表达量始终高于对照组,以响应逆境胁迫。本研究可为下一步探索IbF3H基因在调控甘薯类黄酮生物合成途径和功能作用奠定基础。  相似文献   

19.
大豆胞囊线虫病3号生理小种(SCN3)是我国东北大豆产区的优势生理小种、危害较为严重,目前我国大豆生产上缺少抗病品种;然而常规育种方法培育抗性品种存在准确性差、遗传进程慢的缺点,因此分子辅助育种已成为培育抗性品种的有效途径之一。本研究根据前人的研究结果以抗大豆胞囊线虫病种质东农L-10为试验材料,克隆了抗病候选基因GmRSCN3-2的全长序列并构建了植物表达载体pCXSN-HA/GmRSCN3-2,进而利用发根农杆菌转化大豆材料来验证该候选基因的抗病性。结果表明:候选基因GmRSCN3-2在转基因植株阳性根内的平均雌虫数与空白对照植株根内的平均雌虫数存在显著差异,即GmRSCN3-2对大豆胞囊线虫病具有明显的抗性。  相似文献   

20.
The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin–Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.  相似文献   

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