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水杨酸对NaCl胁迫下水稻(Oryza Saliva L.)幼苗生理活性的影响   总被引:1,自引:0,他引:1  
用0.2%水杨酸处理1.2%NaCl胁迫下水稻种子,测定其以下几个生理指标,种子的发芽率,发芽势和幼苗中的酯酶,过氧化氢酶以及抗坏血酸的含量,实验结果显示:外源性水杨酸能够相对提高NaCl胁迫下水稻种子萌发后幼苗的过氧化物酶活性和抗坏血酸的含量,同时也能提高水稻种子的发芽率,发芽势,但对酯酶活性影响不大,研究表明水杨酸能提高水稻种子萌发后幼苗的抗盐性,并使水稻种子出苗整齐,一致。  相似文献   
2.
以国家射箭队24名集训队员在集训期和参加国际比赛的唾液Cortisol和SIgA变化作为研究数据,观察训练期和比赛期两者的差异,分析运动员的应激状况,查看比赛期的变化规律,探求合理的干预手段。研究发现:比赛期与训练周期的基础值相比较,运动员的唾液Cortisol上升,而SIgA则下降,其中男运动员在第1、4天升高显著(P〈0.01),女运动员头3天上升明显(P〈0.01);男运动员的SIgA在第1天下降明显(P〈0.01),吃得开女运动员前3天的都有显著下降(P〈0.01);优秀射箭运动员唾液Cortisol在比赛周期上升,SIgA则下降,两者存在着一定的负相关;男子射箭运动员的应激反应上比女子更加敏感和迅速,女子运动员则表现缓慢而平稳。  相似文献   
3.
水杨酸对水稻萌发及冷胁迫下幼苗生理的影响   总被引:1,自引:0,他引:1  
用不同浓度的水杨酸处理水稻种子及冷害胁迫下水稻幼苗,结果发现:低浓度的水杨酸能提高水稻种子的发芽率、发芽势及发芽指数,高浓度的水杨酸则抑制水稻种子的萌发;在冷胁迫下,水杨酸能提高水稻幼苗的过乳化物酶的活性和VitC的含量,不同品种对同一条件下水杨酸处理的反应效果不一样.  相似文献   
4.
Elastase activity was found to be significantly increased in periodontitis (0.872±0.4270 absorbance units/mg protein, mean±S. D., 1.05±0.61 units/ml saliva), gingivitis (0.772±0.416 units/mg protein, 1.515±0.952 units/ml) and diabetes (0.549±0.286 units/mg protein, 1.20±0.769 units/ml) compared to normals (0.255±0.089) units/mg protein, 0.264±0.079 units/ml). Chymotryptic activity was not found to be increased in these disease conditions over the normal level (0.284±0.096 units/mg protein). Aminopeptidase activity was elevated only in periodontitis (0.670+0.140 units/mg protein) compared to normals (0.349±0.100 units/mg protein). Trypsin-like activity was also found to be significantly raised in periodontitis compared to normals when Pro-Phe-Arg-p-nitroanilide (0.666±0.204 units/mg protein), Ile-Pro-Arg-p-nitroanilide (1.59±0.260 units/mg protein) and Pyroglu-Pro-Arg-p-nitroanilide (1.82±0.380 units/mg protein) were used as substrates. The normal values with these three substrates were respectively, 0.454±0.110, 1.04±0.231 and 1.15±0.312 units/mg protein. Total protein level in saliva was found to be significantly elevated in gingivitis (209±66.8 mg/dl) and diabetes (204±68.0) compared to normal values (107±20.7). Increase in periodontitis was marginal (127±28.3 mg/dl). Expression of proteolytic activities normalized to protein level was useful in differential diagnosis. Increase in elastase level in saliva is not a specific marker for periodontal diseases.  相似文献   
5.
目的:应用唾液中分泌型免疫球蛋白(sIgA)的含量指标评定免疫机能;方法:收集整理文献,找到合理的理论依据和分析方案;结果:唾液中sIgA作为分析免疫机能简易指标在指导运动训练和大众健身方面都有重要意义;运动员长期大强度训练可能会导致免疫力下降。这可以从唾液中sIgA含量反映。结论:可以通过唾液中sIgA含量及时调整运动量和强度、合理膳食来预防和缓解机体免疫的下降;对大众健身方面,可以通过分析sIgA的含量监控机体免疫状况,为科学的健身提供客观指标以指导实践。  相似文献   
6.
Oral squamous cell carcinoma is one of the most common malignancies recognized. Biomarkers which can predict presence of cancer and its progression can help in better management of these disorders. Over production of lipid peroxidation byproducts and disturbances in antioxidant defense system have been implicated in the pathogenesis of several diseases including oral cancer. Studies have shown a correlation of butyrylcholinesterase (BChE), with tumourigenesis, cell proliferation and cell differentiation. Earlier we have observed a significant elevation in plasma BChE and protein thiols in oral cancer patients which correlated well with stages of cancer. As it was not clear whether the above markers will be altered in saliva of oral cancer patients this study was undertaken. Institutional Ethics Committee gave permission to carry out this study. Total of 55 subjects comprising healthy controls (n = 30) and biopsy proven oral cancer patients (n = 25) consented to participate in this study. Salivary samples from cases were taken before any definitive treatment. Protein thiols and BChE were estimated in salivary samples using validated assay methods. Oral cancer patients had a significant increase in pre-treatment salivary BChE levels (p ≤ 0.001) and a significant decrease (p ≤ 0.001) in salivary thiols as compared to respective values in controls. Salivary protein thiols and BChE may have a role in pathophysiology of oral cancer. Saliva can be used as a potential non-invasive screening tool in oral cancer patients.  相似文献   
7.
Abstract

In the present study, we assessed the effects of exercise intensity on salivary immunoglobulin A (s-IgA) and salivary lysozyme (s-Lys) and examined how these responses were associated with salivary markers of adrenal activation. Using a randomized design, 10 healthy active men participated in three experimental cycling trials: 50% maximal oxygen uptake ([Vdot]O2max), 75%[Vdot]O2max, and an incremental test to exhaustion. The durations of the trials were the same as for a preliminary incremental test to exhaustion (22.3 min, s x  = 0.8). Timed, unstimulated saliva samples were collected before exercise, immediately after exercise, and 1 h after exercise. In the incremental exhaustion trial, the secretion rates of both s-IgA and s-Lys were increased. An increase in s-Lys secretion rate was also observed at 75%[Vdot]O2max. No significant changes in saliva flow rate were observed in any trial. Cycling at 75%[Vdot]O2max and to exhaustion increased the secretion of α-amylase and chromogranin A immediately after exercise; higher cortisol values at 75%[Vdot]O2max and in the incremental exhaustion trial compared with 50%[Vdot]O2max were observed 1 h immediately after exercise only. These findings suggest that short-duration, high-intensity exercise increases the secretion rate of s-IgA and s-Lys despite no change in the saliva flow rate. These effects appear to be associated with changes in sympathetic activity and not the hypothalamic – pituitary – adrenal axis.  相似文献   
8.
The aim of this study was to determine the effect of carbohydrate (CHO) versus placebo (PLA) beverage consumption on the immune and plasma cortisol responses to a soccer-specific exercise protocol in 8 university team soccer players. In a randomized, counterbalanced design, the players received carbohydrate or placebo beverages before, during and after two 90min soccer-specific exercise bouts (3 days apart) designed to mimic the activities performed and the distance covered in a typical soccer match. Blood and saliva samples were collected before, during and after the exercise protocol. Plasma lactate concentration increased to ~4 mmol.l-1 at 45 and 90 min of exercise in both treatments (P? 0.01). Plasma glucose concentration was significantly lower after 90 min of exercise with ingestion of the placebo than the carbohydrate (PLA: 4.57 +/- 0.12 mmol.l-1; CHO: 5.49 +/- 0.11 mmol.l-1; P? 0.01). The pattern of change in plasma cortisol, circulating lymphocyte count and saliva immunoglobulin A secretion did not differ between the carbohydrate and placebo trials. Blood neutrophil counts were 14% higher 1 h after the placebo trial than the carbohydrate trial (PLA: 4.8 =/- 0.5 x 10 9 cells.l-1; CHO:4.2 +/- 0.5 x 10 9 cells.l-1; P=0.06),but the treatment had no effect on the degranulation response of blood neutrophils stimulated by bacterial lipopolysaccharide. We conclude that, although previous studies have shown that carbohydrate feeding is effective in attenuating immune responses to prolonged continuous strenuous exercise, the same cannot be said for a soccer-specific intermittent exercise protocol. When overall exercise intensity is moderate,and changes in plasma glucose, cortisol and immune variables are relatively small, it would appear that carbohydrate ingestion has only a minimal influence on the immune response to exercise.  相似文献   
9.
The purpose of this study was to evaluate the relationship between the physicochemical properties of saliva such as flow rate, pH, buffering capacity, calcium level, total protein and total antioxidant levels in caries free and caries active children. The present study included one hundred and twenty healthy children who were divided into two groups; group I and group II comprising of age groups 7–10 and 11–14 years, respectively. Both the groups were then sub-divided equally according to gender. They were further divided into caries free and caries active with 15 children in each group. Unstimulated saliva was collected by suction method and flow rates were determined. The samples were then analyzed for pH, buffering capacity, total protein, calcium and total antioxidant capacity. The data was statistically analyzed using student t test (unpaired). The results revealed that when all these parameters were compared among the caries free and caries active children, flow rate, pH, buffering capacity were slightly reduced in caries active children, but total protein and total antioxidant capacity of saliva increased significantly in caries active children and the total calcium decreased significantly in caries active children. Within the limitation of this study, we conclude that, the physicochemical properties of saliva play a major role in the development of caries.  相似文献   
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