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1.
喷施铁肥对铁蛋白转基因水稻的稻米增铁效应研究   总被引：1，自引：0，他引：1  
以豌豆铁蛋白转基因富铁水稻纯系(Fer34)及其原始对照(秀水11)为试材,开展有关转基因富铁系稻米铁含量积累和变异规律研究.结果表明,与CK相比,转基因富铁稻(Fer34)确有更强的稻米积累铁含量功能,但这种富铁程度与所处土壤、气候等生态环境有关;对其灌浆期进行叶面喷施铁肥处理,可以明显增加其稻米的铁含量,且不改变稻米主要外观和蒸煮食用品质,对淀粉特性和结构的RVA谱参数也无明显影响.这表明选用铁蛋白转基因富铁稻,并结合灌浆期喷施铁肥的栽培技术,来生产高效富铁大米,解决人类铁营养缺乏症的技术路线方法是可行的.  相似文献   

2.
Fifty children (1–4 years age) presenting with microcytic hypochromic anemia (hemoglobin less than 10g/dl) were studied in two groups of 25 each. Group I was supplemented with iron (ferrous sulphate 6 mg/kg/d) while group II in addition to iron was also supplemented with vitamin A (5000 IU/d). Hemoglobin concentration was found to be significantly increased after 4 weeks of iron supplementation. Rise in hemoglobin was comparatively more in-group II, as compared to group I, after 8 and 12 weeks. Serum iron was significantly higher after 4 weeks in both the groups. Packed cell volume (PCV) and retinol levels increased significantly in-group II only. The data suggests that supplementation of vitamin A improves hematopoiesis.  相似文献   

3.
The total proteins in human urine have been compared by sulfosalicylic acid, sulfosalicylic acid with sodium sulphate and trichloroacetic acid methods with pyrogallol red molybdate method as there are no studies found quantifying imprecision and bias components. Fresh urine of 36 patients was analyzed by four methods. Imprecision and inaccuracy were determined by repeated analysis and method comparison studies using correlation plots, Bland and Altman, and Passing and Bablok regression analyses respectively. The coefficient of variation was 5.07 % for pyrogallol red molybdate; 6.84 % for sulfosalicylic acid; 3.97 % for sulfosalicylic acid with sodium sulphate and 5.93 % for trichloroacetic acid methods. Bland and Altman analysis showed a bias of 5.8, 1.7 and ?5.4 for pyrogallol red molybdate versus sulfosalicylic acid, sulfosalicylic acid with sodium sulphate and trichloroacetic acid methods respectively. Passing and Bablok regression revealed a constant bias for pyrogallol red molybdate versus all turbidimetric methods but a proportional bias only with trichloroacetic acid method. Sulfosalicylic acid with sodium sulphate method is preferred to sulfosalicylic acid and trichloroacetic acid methods.  相似文献   

4.
Summary  Amoebiasis, caused by an enteric protozoanEntamoeba histolytica, is one of the major parasitic diseases of mankind. Current estimate suggests that the parasite infects about 10% of the world population at any given time. There is an urgent need to characterize the antigenic molecules ofE. histolytica, and find out antigens which have both immunodiagnostic and prophylactic potential against amoebiasis. The results of somatic antigen analysis, using sera from immune or infected individuals, indicated that the wholeE. histolytica trophozoites, are highly complex and heterogeneous in nature and both immunodiagnostic and immuno prophylaxis activity remain mainly in a surface associated 29 kDa glycoprotein ofE. histolytica. Future studies at molecular level particularly, genes responsible for expression of this protein, their homology with other proteins and structure analysis will give better understanding about this polypeptide. Studies on excretory secretory antigens, clearly demonstrated thatE. histolytica like many organisms, also liberates certain antigenic moieties into the culture medium during in vitro cultivation and this antigen has similar diagnostic values like the conventional somatic antigens. It is important that the ESA should be prepared from the supernatant after collecting the cell and use for immunodiagnosis of amoebiasis. This is an additional source of antigen which will help in carrying out more tests using the same reagents. Further studies are needed to clarify the location of these molecules on the parasite, along with detailed biochemical and immunological characterization and their relation with the pathogenesis. This was presented at the symposium on “Recent Trends in Tropical Disease Research”, held at Sevagram on 5-6 September, 1997.  相似文献   

5.
Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1st, 2nd and 3rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1st, 2nd and 3rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function relationship of these proteins relevant for diagnosis and pathogenesis.  相似文献   

6.
Dietary spice components ofCurcuma longa andAbroma augusta have been screened for their protective effect against reactive oxygen species induced lipid peroxidation. They have been found to be efficient antioxidant when administered in combination. The purpose of the study was to investigate the effect of oral administration (300mg/Kg) of the aqueous extract of turmeric whose active ingredient isCurcumin andAbromine powder as a hypoglycemic agent mixed with diet. The effect of this aqueous extract on blood glucose, lipid peroxidation (LPO) and the antioxidant defense system in rat tissues like liver, lung, kidney and brain was studied for 8 weeks in streptozotocin induced diabetic rats. The administration of an aqueous extract of turmeric and abromine powder resulted in a significant reduction in blood glucose and an increase in total haemoglobin. The aqueous extract also resulted in decreased free radical formation in the tissues studied. The decrease in thiobarbituric acid reactive substances (TBARS) and increase in reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) clearly showed the antioxidant property of the mixture. It is suggested that these changes initially counteract the oxidative stress in diabetes however, a gradual decrease in the antioxidative process may be one of the factors which results in chronic diabetes. These results indicate that the mixture of the two plants have shown antidiabetic activity and also reduced oxidative stress in diabetes. A combination ofAbroma augusta and Curcuma longa also restored the other general parameters in diabetic animals. The results were statistically analyzed and indicated that combination of herbal extracts showed better efficacy as compared to individual herbal plant extracts used.  相似文献   

7.
刘莉  赵伟军  姚莉  仲伟俊 《中国软科学》2005,(10):80-88,119
我国铅锌工业发展带来的环境问题日趋严重,已阻碍了该行业的可持续发展.本文在对有色铅锌工业的环保问题进行制度经济分析的基础上,提出在我国建立污染权交易理论,从宏观经济政策、制度方面提出了促使有色铅锌工业可持续发展的管理对策.  相似文献   

8.
BackgroundTraditional methods of obtaining arsenic have disadvantages such as high cost and high energy consumption. Realgar is one of the most abundant arsenic sulphide minerals and usually treated as waste in industry. The aim of the present study was to screen an arsenic tolerant bacterium used for bioleaching arsenic from realgar.ResultsAn acidophilic iron-oxidizing bacterium BYQ-12 was isolated from Wudalianchi volcanic lake in northeast China. BYQ-12 was a motile, rod-shaped gram-negative bacterium with an optimum growth at 30°C and pH 2.5. 16S rDNA phylogeny showed that BYQ-12 was a new strain of Acidithiobacillus ferrooxidans. The inhibitory concentrations (ICs) of arsenite and arsenate were 32 and 64 mM, respectively. A significant second-order model was established using a Box–Behnken design of response surface methodology (BBD-RSM) and it estimated that a maximum arsenic bioleaching rate (73.97%) could be obtained when the pulp concentration, pH and initial ferrous ion concentration were set at optimized values of 0.95% w/v, 1.74 and 3.68 g/L, respectively. SEM, EDS and XRD analyses also revealed that there was direct bioleaching besides indirect electrochemical leaching in the arsenic bioleaching system.ConclusionFrom this work we were successful in isolating an acidophilic, arsenic tolerant ferrous iron-oxidizing bacterium. The BBD-RSM analysis showed that maximum arsenic bioleaching rate obtained under optimum conditions, and the most effective factor for arsenic leaching was initial ferrous ion concentration. These revealed that BYQ-12 could be used for bioleaching of arsenic from arsenical minerals.  相似文献   

9.
大型复杂污染场地的污染治理修复是国内外环境领域面临的重大难题。大型复杂污染场地具有影响范围广、污染物种类多、生态环境威胁大等特征,这类场地污染物的环境行为认知和高效治理修复都面临巨大挑战,其中土壤和地下水污染的形成机制、污染源的精准识别、智能决策优化等关键科技问题亟待解决。我国大型复杂污染场地在京津冀、长江经济带、珠江三角洲等经济发达地区呈集群式分布,涉及化学品制造业、石油等燃料加工业、黑色金属冶炼等行业。基于我国国情,文章提出了大型复杂污染场地修复治理的关键“三步曲”（TSRTCM）,从调查评估与科学认知、方案决策与技术筛选、工程实施与监测评价3方面着力破解修复治理难题。大型复杂污染场地环境修复能有力支撑污染防治攻坚战,有助于区域经济社会绿色发展。  相似文献   

10.
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation, nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help combat the risk of developing such disorders in ensuing years.  相似文献   

11.
The ubiquitous fungus Aspergillus fumigatus causes allergic rhinitis, asthma, sinusitis and allergic bronchopulmonary aspergillosis. A number of major allergens from A. fumigatus are purified, but their structure-function role in the pathogenesis of disease is not known. Such information is essential for devising alternative therapy of fungal allergic diseases. In the present study, N-terminal and C-terminal deletion mutants ofAsp f 3 were constructed and their immunopathological responses studied in a mice model of allergy. Three mutants viz,Asp f 3 (aa 33–168), (aa 1–142), and (aa 23–142) were made by deleting certain amino acids from epitopic regions of full lengthAsp f 3, a major allergen of A. furnigatus. TheAsp f 3 and three mutated proteins were expressed in pET vector. The C-terminal deletion mutantAsp f 3 (aa 1–142) induced elevated IFN-γ but low levels of IL-4 by spleen cells. This mutant also showed significant downregulation of peripheral blood eosinophils and lung inflammation in immunized mice. The N-terminal deletion mutantAsp f 3 (aa 33–168) also exhibited an immuno-suppressive effect in terms of IgE production and induction of Th2 cytokine. The results indicate thatrAsp f 3 and its deletion mutants induced distinct immune-inflammatory responses in mice on challenge with these proteins. The non-IgE binding deletion mutants ofAsp f 3 (aa 1–142 and aa 33–168) could deviate Th2 immune response with a concomitant reduction in airway inflammation and infiltration of inflammatory cells.  相似文献   

12.
The sarcoplasmic reticulum was isolated and characterized in the pure form from normal caprine (Capra hircus) hearts. Under ischemic condition, fatty acids like palmitic acid, palmitoyl carnitine and oleic acid accumulatein vivo. These are known to have a detrimental effect on membrane components. The effects of simulated ischemia on the Ca2+-ATPase were studied using these fatty acidsin vitro at concentrations at which they occurin vivo in the ischemic heart. All three fatty acids inhibited Ca2+-ATPase activity. At lower concentrations, palmitoyl carnitine was the most potent, followed by oleic acid while palmitic acid displayed the least potency. Electron microscopy studies with fatty acids showed morphological disruptions in SR vesicles. The decline in Ca2+-ATPase activity could be attributed to the change in membrane morphology.  相似文献   

13.
A number of preparations are available in Ayurved for treatment of anemia and iron deficiency. This study was designed to evaluate efficacy of some of them. Six most commonly used Ayurvedic iron containing preparations (Navayasa Curna, Punarnavadi Mandura, Dhatri Lauha, Pradarantaka Lauha, Sarva-Juara-Hara Lauha and Vrihat Yakrdari Lauha) were given in a dose of 250 mg b.d. for 30 days to six groups of iron deficient anemic patients; each group consisting of 20 patients. A control group was given Allopathic preparation—Irex-12, (containing—ferrous fumarate, vitamin C, folic acid and vitamin B12); 1 capsule daily for 30 days for comparison. All hematological and iron parameters were determined before and after completion of treatment. The results showed that there was statistically significant rise (p<0.001) in all of them—Hb, PCV, TRBC, MCV, MCH, MCHC and plasma iron, percent saturation and plasma ferritin. Total iron binding capacity decreased significantly (p<0.001). The response of most of Ayurvedic preparations was better than Allopathic preparation and there was no side effect as observed with iron salts The Hb regeneration rate was 0.10 g/dl/day for Allopathic preparation; while it was above this value for all Ayurvedic preparations exceptPradarantaka Lauha which was least effective.Sarva-Juara-Hara Lauha was the drug of choice as Hb regeneration with it was highest 0.16 g/dl/day. Upon analysis of Ayurvedic drugs, these results were found to be consistent and correlated with iron content of the preparation.  相似文献   

14.
Social media systems have encouraged end user participation in the Internet, for the purpose of storing and distributing Internet content, sharing opinions and maintaining relationships. Collaborative tagging allows users to annotate the resulting user-generated content, and enables effective retrieval of otherwise uncategorised data. However, compared to professional web content production, collaborative tagging systems face the challenge that end-users assign tags in an uncontrolled manner, resulting in unsystematic and inconsistent metadata.This paper introduces a framework for the personalization of social media systems. We pinpoint three tasks that would benefit from personalization: collaborative tagging, collaborative browsing and collaborative search. We propose a ranking model for each task that integrates the individual user’s tagging history in the recommendation of tags and content, to align its suggestions to the individual user preferences. We demonstrate on two real data sets that for all three tasks, the personalized ranking should take into account both the user’s own preference and the opinion of others.  相似文献   

15.
This study examines the extent to which politicians' visibility in traditional news coverage explains individual politicians' visibility on social media, and vice versa. We also explore whether these relationships depend on commonly identified characteristics of individual politicians. We collected data for all elected candidates from the 2012 Dutch national elections covering each 15 days prior to the election day (N = 2250). This includes 2736 newspaper articles and 77,597 mentions on Facebook and Twitter. Our results show that the traditional news agenda and social media agenda impact each other, but that the reciprocal influence is not independent of politician characteristics.  相似文献   

16.
第二外语教学是大学外语教学活动中非常重要的一部分,但目前我国各大学的第二外语教学活动还存在很多偏差。本文以日语作为第二外语为例,将教育心理学理论引入到外语教学活动中来,着重讨论了针对第二外语教学对象的个体差别,教学者应该采取的相应对策;并从教学者自身的教学策略和教学能力等条件出发,展开说明了教学者除了需要教授课本知识和专业知识之外,还要适当地发挥积极意识的影响作用。  相似文献   

17.
本文收集了国内曼陀罗属(Datura L.)  11个不同的生态型，在光学显微镜和扫描电镜下，进行了花粉粒形态的比较观察。该属花粉粒均为球形或稍扁，具3孔沟型。花粉粒外壁表面的纹饰可作为分属、分组、分种的依据之一。可分为三个类型，与植物形态分类基本一 致，即：具皱波-细网状纹饰(曼陀罗组); 具网状条纹或条纹，条脊表面有细颗粒或粗糙(洋金花组); 具条纹，条脊表面有蚕体状环纹及细颗粒(木本曼陀罗组)。种以下的变种或栽培变种，花粉粒的形态特征不足以作为分类的依据。  相似文献   

18.
It is intuitively clear that putting the cart before the horse is not the same as putting the horse before the cart. It is equally clear that a history of philosophy is different from a philosophy of history. Yet there is no logical relationship, like the AND/OR/NOT functions, which would enable manipulation of these permuted, non-commutative, relationships. In this paper we present a system for automatic handling of ordered sets, states based on these sets, and of differing points of view regarding a Universe of Discourse. We call what we are dealing with aspects and we represent them by means of a new logical function called the Overlap function.  相似文献   

19.
This study was carried out to see the effect of the aqueous extract ofOcitum sanctum Linn (Tulsi) with Vitamin E on biochemical parameters and retinopathy in the streptozotocin-induced diabetic albino male rats. Adult albino male rats weighing 150–200 gm were made diabetic by intraperitoneal injection of streptozotocin in the dose 60 mg/kg in citrate buffer (pH 6.3). The diabetic animals were left for one month to develop retinopathy. Biochemical parameters like plasma glucose, oral glucose tolerance and glycosylated hemoglobin HbA1c, were measured along with lipid profile, and enzymes like glutathione peroxidase (GPX), lipid peroxidase (LPO), superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) in normal, untreated diabetic rats and diabetic rats treated withOcimum sanctum L extracts and vitamin E. Fluorescein angiography test was done for assessing retinopathy. Results on biochemical parameters were analyzed statistically by using ANOVA followed by Dunnet's ‘t’-test. A p-value of <0.05 was considered as significant. Evaluation of biochemical profile in treated groups showed statistically significant reduction in plasma levels of glucose, HbA1c, lipid profile and LPO, and elevation of GPX, SOD, CAT and GST. Treatment of the diabetic animals withOcimum sanctum and Vitamin E, alone and in combination for 16 weeks showed reversal of most of the parameters studied including plasma glucose levels. Angiography showed improvement in retinal changes following combined antidiabetic treatment.  相似文献   

20.
Conditions like hypertension, atherosclerosis and diabetes are known to be the result of endothelial dysfunction which could begin early in the life of an individual. The markers of endothelial dysfunction studied in the present work are plasma hemoglobin, serum high sensitivity C-reactive protein (hsCRP) and plasma nitrite and nitrate. We studied the onset of endothelial dysfunction with increase in age as well as in disease condition like newly detected hypertensives and of hypertensive diabetic patients. The mean plasma hemoglobin and hsCRP values were found to increase with age. hsCRP and plasma hemoglobin levels were significantly higher in patient groups as compared to aged-matched controls. On the other hand nitrate and nitrite was significantly higher in patients who suffered from both diabetes and hypertension together and nitrate values were significantly lower in patients who suffered from hypertensive alone. Plasma hemoglobin and hsCRP are associated with endothelial dysfunction and increases both with age as well as in disease condition.  相似文献   

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