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1.
A pot culture experiment was conducted on a loamy sand soil to study the effect of FYM and Fe on dry matter yield and uptake of nutrients by oats (Avena sativa) crop in green-house. Application of Fe @ 5 and 20 ppm increased dry matter yield by 5.11 and 11.55 per cent, respectively. The per cent increase in dry matter yield over control with the application of 0.5 and 1.0 percent FYM was 19.06 and 30.07, respectively. Application of FYM increased concentration and uptake of P significantly. Phosphorus uptake increased by 23.60, 54.38, 91.01 and 134.61 per cent over control with 0.5, 1.0, 2.0 and 4.0 per cent FYM, respectively. Phosphorus concentration decreased at 20 ppm Fe but uptake increased significantly at 5 ppm Fe. Concentration and uptake of Ca increased with increasing amounts of Fe and application of FYM decreased concentration of Ca but uptake increased upto 1.0 per cent FYM over control. The Mg concentration and uptake decreased significantly with increased amount of Fe. Application of FYM also decreased Mg concentration but its uptake increased upto 1.0 per cent FYM and then decreased.Iron concentration and uptake increased upto 2 per cent FYM and then decreased. Whereas concentration of Fe decreased with increased amount of applied Fe but its uptake increased nonsignificantly with increased amount of added Fe.Managenese concentration and uptake decreased significantly with increased amount of applied Fe. Managenese concentration increased upto 0.5 per cent FYM but its uptake continued increasing with increasing amounts of applied FYM.  相似文献   

2.
选用籽粒蛋白质含量不同的小麦(Triticum aestivum)品种,运用离体穗培养技术,研究了谷氨酰胺供应水平对小麦穗籽粒重、淀粉和蛋白质及其组分积累的影响.实验结果表明,随着培养基中谷氨酰胺供应水平的提高,粒重、籽粒淀粉和蛋白质积累量均呈单峰曲线,在6 g·L-1谷氨酰胺水平时达到最大值;籽粒氨基酸和蛋白质含量随谷氨酰胺浓度的提高呈上升趋势,而淀粉含量呈下降趋势.籽粒清蛋白和球蛋白含量的变化与总蛋白质含量变化趋势一致,而醇溶蛋白和麦谷蛋白含量在2~6 g·L-1谷氨酰胺浓度范围内呈上升趋势,此后则无明显变化.  相似文献   

3.
选用籽粒蛋白质含量不同的小麦(Triticam aestivum)品种, 运用离体穗培养技术, 研究了谷氨酰胺供应水平对小麦穗籽粒重、淀粉和蛋白质及其组分积累的影响。实验结果表明, 随着培养基中谷氨酰胺供应水平的提高, 粒重、籽粒淀粉和蛋白质积累量均呈单峰曲线, 在6 g.L-1谷氨酰胺水平时达到最大值; 籽粒氨基酸和蛋白质含量随谷氨酰胺浓度的提高呈上升趋势, 而淀粉含量呈下降趋势。籽粒清蛋白和球蛋白含量的变化与总蛋白质含量变化趋势一致, 而醇溶蛋白和麦谷蛋白含量在2~6 g.L-1谷氨酰胺浓度范围内呈上升趋势, 此后则无明显变化。  相似文献   

4.
分别以PEG-6000、NaCl模拟干旱胁迫及盐胁迫,采用水培方法研究了抗旱耐盐冬小麦沧-6001在干旱胁迫、盐胁迫条件下叶片可溶性糖、脯氨酸和可溶性蛋白质含量的动态变化以及Na+、K+在地上部和根系的分布。结果表明可溶性糖和可溶性蛋白变化趋势相似,其含量随干旱胁迫或盐胁迫时间延长而增加,但在胁迫处理后期下降,并且随胁迫强度增加,二者出现下降时间提前;脯氨酸在干旱胁迫条件下快速积累达到峰值后下降但在胁迫处理后期再次增加,在盐胁迫条件下,随胁迫强度的增加和胁迫时间的延长而增加;Na+在干旱胁迫下随胁迫程度增加而下降,盐胁迫条件下随胁迫程度的增加而增加,K+在干旱胁迫或盐胁迫下均随胁迫程度的增加而下降,且在根系中下降的速度大于地上部。  相似文献   

5.
1. Adipocytes were isolated from epididymal white fat and interscapular brown fat of male rats, and activities of 5'-nucleotidase, adenosine deaminase and adenosine kinase were measured in cell extracts. 2. 5'-Nucleotidase activity in white adipocytes was increased in streptozotocin-diabetes, decreased in hypothyroidism and increased with age. That activity in brown adipocytes was unchanged in diabetes, decreased in hypothyroidism and increased with age. 5'-Nucleotidase activity was higher in white adipocytes from female rats. 3. Adenosine deaminase activity in white adipocytes was increased in diabetes, decreased in hypothyroidism and increased with age. That activity in brown adipocytes was decreased in diabetes and hypothyroidism. 4. Adenosine kinase activity in both cell types was unchanged in diabetes or hypothyroidism, but increased with age.  相似文献   

6.
UV-B辐射对仙客来的生理效应   总被引:1,自引:0,他引:1  
通过室内模拟试验,研究了不同强度UV-B辐射(10μW/cm2和20μW/cm2)对仙客来(Cyclamen persicum Mill)生理的影响。结果表明:(1)UV-B辐射的增加对仙客来叶片光合色素的含量具有影响;(2)叶片质膜透性随UV-B辐射强度的增加而增加,随UV-B辐射时间的延长而增加;(3)叶片类黄酮含量随UV-B辐射强度的增加而增加,且在40d时达到最大值;(4)增强UV-B辐射下,仙客来花瓣中的花青素含量增加。  相似文献   

7.
Changes in precipitation regimes and wind velocity tend to alter structure and composition of the annual herb plant community, with consequent effects on ecological functioning and biodiversity maintenance. We examined the effects of increased precipitation and reduced wind velocity on annual herb plant community characteristics via a manipulative experiment from the middle of April to middle of August, 2016. There was significant increment in species richness with increased precipitation from June to August, and there were interactive effects between increased precipitation and reduced wind velocity especially in June and the end of July. From June to August, increased precipitation, reduced wind velocity as well as their interaction stimulated sandy plant community development. There was considerable elevation in plant coverage with increased precipitation, and also there was an interactive effect of increased precipitation with 20% reduced wind velocity. However, reduced wind velocity caused more significant stimulation (p < .01) in plant height. Moreover, dominant plants, Salsola collina, Bassia dasyphylla, and Setaria viridis, contributed equally to the elevated community coverage with increased precipitation, whereas S. collina occupied a much larger proportion on the augment of community height compared with the other two species under the increased precipitation and reduced wind velocity. Elevated Shannon–Wiener index was detected with increased precipitation in June and July. Furthermore, increased precipitation and reduced wind velocity enhanced aboveground and belowground biomass, respectively. These species traits‐in structuring and composing plant community were suggested to be conducive to deep understanding the plant functioning and dynamics under global changing precipitation regimes and atmospheric wind velocity scenarios.  相似文献   

8.
Tamoxifen can induce hepatic steatosis in women. In this study, we wanted to elucidate the mechanism behind the tamoxifen-induced accumulation of triacylglycerol in liver in female rats, and we hoped to prevent this development by combination treatment with the modified fatty acid tetradecylthioacetic acid (TTA). The increased hepatic triacylglycerol level after tamoxifen treatment was accompanied by decreased acetyl-coenzyme A carboxylase (ACC) and FAS activities, increased glycerol-3-phosphate acyltransferase (GPAT) activity, and a tendency to increased diacylglycerol acyltransferase (DGAT) activity. The activities and mRNA levels of enzymes involved in beta-oxidation, ketogenesis, and uptake of lipids from liver were unaffected by tamoxifen, whereas the uptake of lipoproteins was unchanged and the uptake of fatty acids was decreased. Combination treatment with tamoxifen and TTA (Tam+TTA) normalized the hepatic triacylglycerol level and increased the activities of ACC, FAS, GPAT, and DGAT compared with tamoxifen-treated rats. The activities and mRNA levels of enzymes involved in beta-oxidation, ketogenesis, and uptake of lipids were increased after Tam+TTA treatment. In conclusion, tamoxifen increased the hepatic triacylglycerol level, probably as a result of increased triacylglycerol biosynthesis combined with unchanged beta-oxidation. The tamoxifen-induced accumulation of triacylglycerol was prevented by cotreatment with TTA, through mechanisms of increased mitochondrial and peroxisomal beta-oxidation.  相似文献   

9.
Growth of minnows, Phoxinus phoxinus , weighing 1-5.5 g was studied experimentally at five ration levels from starvation to ad libitum and four temperatures ranging from 5 to 15°C. The relationship between specific growth rate (SGR) and ration was a decelerating curve. SGR at maximum rations increased with increased temperature, but at restricted rations it decreased with increased temperature. Predictive models for the specific growth rates were developed using multiple regression. Maintenance rations and optimum rations both increased with increased temperature. Maintenance rations were less sensitive to temperature than optimum rations and mostly lay between 1 and 2% of body weight per day. Conversion efficiencies increased with increased ration from zero value at the maintenance ration to a peak at the optimum ration, then decreased with further increases in ration. At a given restricted ration level, conversion efficiencies generally decreased with increased temperature. At maximum rations, conversion efficiencies were relatively insensitive to temperature. Growth in wet weight, dry weight and energy content showed similar responses to ration, temperature and body weight.  相似文献   

10.
Cystic fibrosis patients and their parents have increased alpha-adrenergic sensitivity, increased cholinergic sensitivity, and reduced beta-adrenergic sensitivity. This combination of autonomic aberrations has been associated with increased airway reactivity in other disease populations. Although studies of airway reactivity are difficult to interpret in the cystic fibrosis patients themselves, the parents have no apparent pulmonary infection or inflammation, and one-third of these people have increased airway reactivity. Moreover, parents of children with cystic fibrosis have increased prevalence of wheezing and lung disease in childhood. Airway reactivity has been associated in other populations, with increased risk of obstructive pulmonary disease. Further studies are required to test the hypothesis that heterozygosity for CF is a risk factor for development and progression of obstructive pulmonary disease.  相似文献   

11.
Herbaceous plant species richness typically declines with increasing productivity, but differences in the resources underlying these gradients are often ignored. This study adds to the small number of studies examining the effects of water and mineral nutrients on biomass and richness in oldfield communities. We established 60 4 m2 plots in a goldenrod-dominated oldfield to test the differential effects of water and mineral nutrients on community properties. Species richness declined with added nutrients, but increased with added water. Aboveground biomass increased only when both nutrients and water were added. Leaf area index increased with added nutrients alone, although the increase was greater when water was also added. Understory light levels decreased with added nutrients, but not with added water; however, the per-gram effect of biomass on understory light levels did not vary significantly among nutrient and water treatments. Our results suggest that water tends to enhance productivity, but does not cause the common decline in species richness that typically accompanies nitrogen additions. Rather, water increased richness through positivie effects on either germination and establishment, or increased survival. These results are consistent with either increased light limitation or increased water limitation causing loss of species from nitrogen-rich habitats.  相似文献   

12.
A case control study of gall stone disease in relation to diet, alcohol, and relative weight was undertaken. The study population comprised 267 hospital patients with newly diagnosed gall stone disease, 241 individually matched controls selected from the community, and 359 controls who were patients in hospital. Dietary intake was estimated with a quantitative food frequency questionnaire. Multiple logistic regression analysis was used to estimate the net association between individual nutrients and the risk of formation of gall stones. Variations in risk with sex and age were examined in the light of prior evidence of influences of sex hormones and age on hepatobiliary metabolism. In both sexes increased intake of alcohol was associated with a decreased risk of developing gall stones; increased intake of simple sugars in drinks and sweets was associated with an increased risk; and increased intake of energy or fat was associated with an increased risk in young subjects. Obesity was associated with an increased risk only in young women.  相似文献   

13.
This study was conducted to evaluate the chronic effects of eicosapentaenoic acid (EPA) on fatty acid and glucose metabolism in human skeletal muscle cells. Uptake of [14C]oleate was increased >2-fold after preincubation of myotubes with 0.6 mM EPA for 24 h, and incorporation into various lipid classes showed that cellular triacylgycerol (TAG) and phospholipids were increased 2- to 3-fold compared with control cells. After exposure to oleic acid (OA), TAG was increased 2-fold. Insulin (100 nM) further increased the incorporation of [14C]oleate into all lipid classes for EPA-treated myotubes. Fatty acid beta-oxidation was unchanged, and complete oxidation (CO2) decreased in EPA-treated cells. Basal glucose transport and oxidation (CO2) were increased 2-fold after EPA, and insulin (100 nM) stimulated glucose transport and oxidation similarly in control and EPA-treated myotubes, whereas these responses to insulin were abolished after OA treatment. Lower concentrations of EPA (0.1 mM) also increased fatty acid and glucose uptake. CD36/FAT (fatty acid transporter) mRNA expression was increased after EPA and OA treatment compared with control cells. Moreover, GLUT1 expression was increased 2.5-fold by EPA, whereas GLUT4 expression was unchanged, and activities of the mitogen-activated protein kinase p38 and extracellular signal-regulated kinase were decreased after treatment with OA compared with EPA. Together, our data show that chronic exposure of myotubes to EPA promotes increased uptake and oxidation of glucose despite a markedly increased fatty acid uptake and synthesis of complex lipids.  相似文献   

14.
目的:探讨反应性血小板增高患者凝血指标及血小板聚集功能指标变化规律。方法:143例血小板反应性增高患者和65例对照者同时检测血小板聚集功能、抗凝血酶活性(AT-Ⅲ)、凝血酶原时间(PT)和活化部分凝血活酶时间(APTT),并统计分析。结果:血小板反应性增高常见于肿瘤、肺炎、外伤患者;血小板反应性增高组患者AT-Ⅲ、PT和APTT与对照组无差异,但患者血小板聚集功能显著高于对照组。结论:血小板反应性增高患者血小板聚集功能增强,建议定期监测血小板聚集功能,必要时用抗血小板聚集药预防。  相似文献   

15.
四季竹对不同浓度NaCl胁迫的生理响应   总被引:2,自引:0,他引:2  
以夏秋季优良笋用竹种四季竹盆栽苗为材料,研究了土壤中1‰~6‰浓度NaCl(干重)处理对四季竹叶片脱落率、离子渗漏率、丙二醛(MDA)含量、抗氧化酶活性以及渗透调节物质含量的变化特征,以探讨四季竹的抗盐机理。结果表明:(1)随NaCl浓度的增大和处理时间的延长,四季竹叶片脱落率逐渐增加;四季竹在1‰~2‰NaCl浓度下的土壤中生长良好,在3‰~5‰浓度下随处理浓度的增大伤害逐渐加重,但这种伤害是可逆的,6‰是四季竹的半致死盐浓度。(2)叶片离子渗漏率随NaCl浓度的增大而显著增大,在6‰浓度处理下随处理时间的延长近直线升高,在3‰~5‰浓度下先升高后降低,而在1‰~2‰浓度处理下变化平缓且与同期对照无显著差异;叶片MDA含量随NaCl浓度的增大而增加,随处理时间的延长先增加后降低。(3)四季竹叶片SOD和POD活性在胁迫3~15 d均出现先下降后上升的过程,其有一定的锻炼适应性;叶片脯氨酸含量随NaCl处理浓度的增大而增加,其随处理时间的延长在1‰~2‰浓度处理下变化平缓,在3‰~6‰浓度处理下显著增加后减小;各浓度处理的可溶性蛋白含量随处理时间的延长先增加后减小,但均高于对照。研究发现,四季竹是较耐盐竹种,其可以通过调控自身保护酶活性和渗透调节物质含量来有效缓解盐胁迫伤害,从而表现出一定的耐盐能力。  相似文献   

16.
The diabetic state confers an increased propensity to accelerated atherogenesis. In addition to the established risk factors, there is evidence for increased oxidative stress and inflammation in diabetes. Increased oxidative stress is manifested by increased lipid peroxidation (e.g. increased F 2 -isoprostanes) and increased DNA damage. Evidence for increased inflammation includes increased monocyte superoxide and pro-inflammatory cytokine release (IL-1, IL-6, and TNF- &#102 ), increased monocyte adhesion to endothelium and increased levels of plasma C-reactive protein, the prototypic marker of inflammation. Most importantly, alpha tocopherol therapy, especially at high doses, clearly shows a benefit with regards to LDL oxidation, isoprostanes and a decrease in inflammatory markers such as C-reactive protein, pro-inflammatory cytokines and PAI-1 levels. Thus, it appears that, in diabetes, alpha tocopherol therapy could emerge as an additional therapeutic modality.  相似文献   

17.
Many mammals exhibit a periparturient relaxation of previously established immune responses (PPRI) to gastrointestinal nematodes culminating in increased worm burdens. It has been suggested that the extent of PPRI may have a nutritional basis as it is considerably augmented when protein supply is scarce. Subsequent studies have shown that increased dietary protein intake can ameliorate this phenomenon. However, this effect is often confounded with increased food intake and thus increased energy levels. Herein, we aimed to dissect the effects of protein and energy nutrition on the immune status and resistance to re-infection with gastrointestinal nematodes in the periparturient host. The lactating, Nippostrongylus brasiliensis re-infected rat was utilised as an established model for mammalian PPRI. Experimental animals were assigned to restricted feeding regimens designed to achieve four pre-determined levels of crude protein (CP) at one of two levels of metabolisable energy (ME) and parasitological and immunological measurements taken at either day 6 or day 9 post re-infection. We clearly show that increased supply of dietary CP, but not increased dietary ME, significantly reduced worm burdens. The increased magnitude of worm expulsion with increased dietary CP supply strongly correlated with mucosal mast cell accumulation in the small intestine. In addition, increased CP and not ME supply increased mucosal eosinophil numbers. Furthermore, increased CP led to higher levels of total IgG at high ME only and there were interactive effects of CP and ME on serum levels of IgG1 and IgG2a. Perhaps surprisingly, CP nutrition did not affect expression of either Th1 (IFN-γ) or Th2 (IL-4, IL-13) cytokines in the mesenteric lymph nodes. These data emphasise the role of immunonutrition, and particularly dietary protein, in combating infectious disease such as gastrointestinal parasitism.  相似文献   

18.
It has been proposed that iron depletion protects against cardiovascular disease. There is increasing evidence that one mechanism for this protection may involve a reduction in iron levels within atherosclerotic plaque. Large increases in iron concentration are seen in human atherosclerotic lesions in comparison to levels in healthy arterial tissue. In animal models, depletion of lesion iron levels in vivo by phlebotomy, systemic iron chelation treatment or dietary iron restriction reduces lesion size and/or increases plaque stability. A number of factors associated with increased arterial disease or increased cardiovascular events is also associated with increased plaque iron. In rats, infusion of angiotensin II increases ferritin levels and arterial thickness which are reversed by treatment with the iron chelator deferoxamine. In humans, a polymorphism for haptoglobin associated with increased cardiovascular disease is also characterized by increased lesional iron. Heme oxygenase 1 (HO1) is an important component of the system for mobilization of iron from macrophages. Human HO1 promoter polymorphisms causing weaker upregulation of the enzyme are associated with increased cardiovascular disease and increased serum ferritin. Increased cardiovascular disease associated with inflammation may be in part caused by elevated hepcidin levels that promote retention of iron within plaque macrophages. Defective retention of iron within arterial macrophages in genetic hemochromatosis may explain why there is little evidence of increased atherosclerosis in this disorder despite systemic iron overload. The reviewed findings support the concept that arterial plaque iron is a modifiable risk factor for atherogenesis.  相似文献   

19.
20.
Increasing plasma free fatty acids decreased the degree of glycogen depletion, and increased the citrate concentration, in slow-red (soleus) and fast-red (deep portion of vastus lateralis) muscle during exercise (approx. 50% depletion of glycogen, as against 75% in control animals). There was no effect in fast-white muscle (superficial portion of vastus lateralis). Glycogen concentration in the liver decreased by 83% in controls, but only by 23% in animals with increased free fatty acids during exercise. The decreased glycogen depletion may be partly explained by the findings that (a) plasma-insulin concentration was two- to three-fold higher in animals with increased plasma free fatty acids and (b) the exercise-induced increase in plasma glucagon was lessened by increased free fatty acids. Blood glucose was higher in the animals with increased free fatty acids after the exercise. The rats with increased plasma free fatty acids utilized approx. 50% as much carbohydrate as did the controls during the exercise.  相似文献   

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