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1.
以表达Cry1Ab杀虫蛋白的两种转Bt基因抗虫玉米MON810和Bt11为材料,采用ELISA方法研究了玉米散粉时沉积在植株叶腋处Bt玉米花粉中Cry1Ab杀虫蛋白的田间降解动态,比较了两种Bt玉米花粉中Cry1Ab杀虫蛋白的降解速度.结果表明, Bt玉米花粉中Cry1Ab杀虫蛋白是逐渐降解的,且降解速度逐渐加快.但两种Bt玉米花粉中Cry1Ab杀虫蛋白降解速度不同, MON810中的Bt杀虫蛋白降解较快,而Bt11中的降解较慢. D 15时在MON810叶腋处的花粉中已经检测不到Bt杀虫蛋白,而在Bt11花粉中Bt杀虫蛋白到d 18才完全降解.两种Bt玉米花粉中杀虫蛋白的初始含量差异显著,且在各个取样时间内Bt杀虫蛋白的残留量存在显著差异.玉米散粉时留在田间的Bt玉米花粉中的Cry1Ab杀虫蛋白不会在自然界累积.  相似文献   

2.
美国红鱼卵黄原蛋白的分离纯化及电泳性质鉴定   总被引:1,自引:0,他引:1  
腹腔注射0.02mg/gBW17β-雌二醇,诱导美国红鱼1wk后取尾静脉血,离心分离得到的血浆经Sephacryl S-300 high resolution分子筛分离、纯化卵黄原蛋白.常规聚丙烯酰胺凝胶电泳的考马斯亮蓝染色和糖、磷、脂的特征性基团染色结果表明,17β-雌二醇诱导美国红鱼产生了两种形式的卵黄原蛋白,以Native-PAGE方法计算出美国红鱼两种卵黄原蛋白的分子量分别为344×103和247×103,以SDS-PAGE方法得出卵黄原蛋白3种亚基的分子量为152×103、133×103和118×103.分子筛凝胶过滤能较好地分离纯化美国红鱼血浆中的卵黄原蛋白.图8参17  相似文献   

3.
滇池水华蓝藻藻蓝蛋白的分离纯化与毒性研究   总被引:1,自引:0,他引:1  
采用从昆明滇池机械收获的产毒水华蓝藻为材料,通过采用抽提、粗过滤、微滤、超滤脱毒(截留分子量100 kDa)、低温静置离心、真空干燥等提取纯化方法,从1kg微囊藻粉中制备纯度(A620/A280)高达1.80的57g藻蓝蛋白干粉,小鼠急性毒性试验显示,纯化的藻蓝蛋白无毒性;LD50大于3.71 g·kg-1,而对照原料藻粉的LD50为0.10 g·kg-1,Ames试验结果显示,5个藻蓝蛋白剂量组回变菌落数均未超过阴性对照菌落数2倍,亦无剂量一效应关系,Ames实验结果阴性,初步通过食品安全性毒理学评价程序.  相似文献   

4.
为开发利用动物蛋白资源大瓶螺,1985年以来分别开展了以螺作动物蛋白饲料的水貂、鸡、鸭、对虾、螃蟹等食物链开发利用研究。各食物链饲养试验结果显示,增重效果和经济效益均很显著,螺的蛋白质转换效率高于国产鱼粉,但稍低于秘鲁鱼粉。  相似文献   

5.
在野生动物物种中,乳汁在传递全氟烃基物质(PFASs)于后代中所起的作用,人类还了解甚少。本文以雌性冠海豹及其生产的一对幼崽为研究对象,在哺乳期间,对母体血浆和乳汁中的8种PFASs进行了定量检测,以及对乳汁在PFASs传递过程中所起的作用进行了分析。选择冠海豹是因为它的泌乳周期短(3~ 4 d),在此期间幼崽仅以乳汁为食。胎盘或乳汁传递成为幼崽体内PFASs的唯一来源。通过对8种PFASs的分析(Σ8PFAS),发现7种存在于所有样品中;因此,乳汁是幼崽体内PFASs的来源。在所有样本中,全氟辛烷磺酰基化合物是优势PFAS。Σ8PFAS的平均浓度为母体血浆中6.0 ng/g蛋白(36 ng/g湿重),乳汁中0.77 ng/g蛋白(3.2 ng/g湿重)以及幼崽血浆中12 ng/g蛋白(66 ng g湿重)。血浆中检测到的PFASs浓度在已有报道的其他海豹物种体内检测到的浓度范围之内,低于已知的实验啮齿动物的毒性阈值。PFASs从母体到幼崽的传递效率的个体差异,依赖于PFASs碳键长度、相对传递量最低的为中间能级键的PFASs (C9-C10)。结果显示母体通过乳汁和胎盘传递PFASs,其中胎盘传递是主导途径。
精选自Randi Gr?nnestad, Gro D. Villanger, Anuschka Polder, Kit M. Kovacs, Christian Lydersen, Bj?rn M. Jenssen, Katrine Borg?. Maternal transfer of perfluoroalkyl subastances in hooded seals. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 763–770, July 2017. DOI: 10.1002/etc.3623
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3623/full
  相似文献   

6.
人载脂蛋白A5(ApoA5)是血浆三酰甘油水平的重要决定因素之一,与心血管疾病密切相关,因此获得高纯度的载脂蛋白A5及其抗体具有重要的意义.本文利用PCR技术,从人肝癌细胞系7721的cDNA中扩增出ApoA5基因,并克隆到pThioHisD载体中导入大肠杆菌Escherichia coli BL21(DE3)中进行表达.经优化条件,发酵得到高效表达的融合蛋白,利用融合蛋白上的一段组氨酸序列,用镍离子亲和柱进行纯化,得到纯度大于95%的融合蛋白.使用纯化蛋白免疫新西兰大耳兔,得到多克隆抗体,Western印迹结果显示此多克隆抗体能与ApoA5特异性结合.图6参28  相似文献   

7.
杜仲叶.粉对肉鸡生产性能及血液生化指标的影响   总被引:3,自引:0,他引:3  
为探明杜仲叶粉对肉鸡生产性能及血液生化指标的影响,按0.5%、1%、1.5%、2%的比例在肉鸡的基础日粮中添加杜仲叶粉,以不添加杜仲叶粉作为对照,经60天饲养试验期后,对各组鸡的日增重、饲料报酬(增重与耗料之比)、胴体品质及血液生化指标进行检测,结果表明:杜仲叶粉能提高肉鸡饲料报酬,改善胴体品质,改善血液生化指标.  相似文献   

8.
利用蛋壳粉对水中的磷进行吸附热力学和动力学研究.结果表明,蛋壳粉对水中的磷具有一定的吸附作用,吸附等温线符合Freundlich方程,吸附ΔH、ΔS与ΔG显示蛋壳粉对水中磷的吸附是自发吸热的物理过程.磷在蛋壳中的吸附动力学曲线存在两个吸附平台,吸附过程符合准二级动力学模型,磷在蛋壳中的吸附可能受到吸附边界层和内部孔道结...  相似文献   

9.
正粉煤灰是燃煤电厂以及煤矸石、煤泥资源综合利用电厂锅炉烟气经除尘器收集后获得的细小飞灰和炉底渣[1].粉煤灰是悬浮颗粒物的主要来源,也是会对地表水和地下水造成污染的有害元素的来源之一.铍进入人体后,难溶的氧化铍主要储存在肺部,可引起肺炎.可溶性的铍化合物主要储存在骨骼、肝脏、肾脏和淋巴结等处,它们可与血浆蛋白作用,生成蛋白复合物,引起脏器或组织的病变而致癌.镍作为一种具有生物学作用的元素,能激活或抑制一系列的酶.镍及其化合物对人皮肤粘膜和呼吸道有刺激作用,可引起皮炎和气管炎.过多的铜进入体内可出现恶心、呕吐、上腹疼痛、急性溶血和肾小管变形等中毒现象.钼对眼睛、皮肤有刺激作用,部分接触者出现尘肺病  相似文献   

10.
为了探讨胎牛血清和血浆对甲醛诱导性细胞内DNA-蛋白质交联的影响,以昆明纯系小鼠直接分离肝细胞为试验材料进行体外染毒实验,采用KCl-SDS沉淀法检测甲醛染毒后肝细胞中DNA-蛋白质交联含量.结果表明,当缺乏胎牛血清和血浆时,500μmol·mL-1甲醛仅引起较低水平的交联效应,而加入胎牛血清和血浆以后,甲醛诱导的DPC极显著上升(p<0.01).血浆作用比胎牛血清更明显,但二者无显著性差异.结果提示,胎牛血清和血浆对甲醛诱导性DPC形成具有促进作用,而不是以前学者认为的缓冲作用,这可能是甲醛远距离毒性的基础.  相似文献   

11.
The objective was to determine the plasmatic enzyme cholinesterase recovery, after being inhibited by an organophosphorous in juveniles of Prochilodus lineatus. Fish were exposed 12 h to a sublethal concentration of 1 mg/l of monocrotophos, and immediately placing in clean water during 12, 24, 48 and 96 h to detoxification. After this period, blood was extracted and plasma were used for the quantification of cholinesterase. The results showed a enzymatic inhibition of 91.9%, 55.1%, 50.4% and 33.4% with 12, 24, 48 and 96 h of recovery, respectively. The enzymatic activity spreads to be normalized with the course of hours and the degree of inhibition obtained initially was very high and sustained in the first 48 h.  相似文献   

12.
The Arabian Gulf catfish Arius thallasinus excretes copious amounts of proteinaceous gel from epidermal cells when threatened or injured. As a means of investigating its biological role, this gel material has been examined to determine the nature of the secretion and its associated biological activities. Over 85% of the dry weight of the gel material is protein with small amounts of lipids, carbohydrates and nucleic acid components. Most of the protein exists as a high molecular weight aggregate of predominantly 13 500 molecular weight monomeric units. Several lytic enzyme activities are found in the gel secretion, one of which catalyzes lysis of red blood cells. Other factors induce clotting in citrate treated plasma and agglutination of red blood cells. The enzymic properties of the gel secretion resemble those of some animal venoms.  相似文献   

13.
Coal fly ash (CFA) is dumped at a deep sea disposal site (1,500m water depth) in the eastern Mediterranean, ca. 70km off the Israeli shore. Since 1989, about one million tons of CFA were dumped at the 200km2 allocated area. Six years of monitoring at the dump-site shows that the CFA is heterogeneously distributed; there are areas where CFA covers about 1.3cm depth of the sea floor while at others no CFA is found. CFA is present as a fine powder, small aggregates and even as large blocks both in the dump-site as well as at its peripheries. Cadmium, copper and zinc concentrations in the CFA decreased as a result of the prolonged contact with sea water at in situ conditions while inconclusive changes in mercury, iron and manganese were detected. No changes were observed for lead, iron and aluminium concentrations. A controlled long term field experiment, now in progress at the site, is expected to clarify further chemical changes occurring in the CFA.  相似文献   

14.
Coal fly ash (CFA) is dumped at a deep sea disposal site (1,500m water depth) in the eastern Mediterranean, ca. 70km off the Israeli shore. Since 1989, about one million tons of CFA were dumped at the 200km2 allocated area. Six years of monitoring at the dump-site shows that the CFA is heterogeneously distributed; there are areas where CFA covers about 1.3cm depth of the sea floor while at others no CFA is found. CFA is present as a fine powder, small aggregates and even as large blocks both in the dump-site as well as at its peripheries. Cadmium, copper and zinc concentrations in the CFA decreased as a result of the prolonged contact with sea water at in situ conditions while inconclusive changes in mercury, iron and manganese were detected. No changes were observed for lead, iron and aluminium concentrations. A controlled long term field experiment, now in progress at the site, is expected to clarify further chemical changes occurring in the CFA.  相似文献   

15.
Diabetes mellitus is a worldwide leading metabolic syndrome, associated with profound alterations in carbohydrate, lipids, lipoproteins and protein metabolisms. Worldwide, traditional practitioners for the treatment of diabetes and its complications use a wide variety of medicinal plants. In the present study the aqueous extract of Tephrosia purpurea leaves (TpALet) was evaluated for its antihyperglycemic and antihyperlipidemic effects in streptozotocin induced diabetic rats. Profound alterations in the concentrations of blood glucose, lipids and lipoproteins were observed in diabetic rats. Oral administration of TpALet to diabetic rats at a dose of 600 mg/kg body weight significantly reduced the level of blood glucose and increased the level of plasma insulin as well as normalized the lipids and lipoproteins profile. The present study thus demonstrated that TpALet has prominent antihyperglycemic and antihyperlipidemic effects in streptozotocin induced diabetic rats.  相似文献   

16.
Two-year old Tinca tinca L. (previously acclimated for at least 3 weeks to defined temperatures) were subjected to slow (24 h) and fast (2 h) temperature changes from 13.5° to 26°C (observational period 504 h) and from 6° to 16°C and vice versa (observational period 288 h). Effects on coefficient of condition, Na, K, Ca and Cl content of plasma, H2O, Na and K content of muscle and liver, and rates of movements of gill-covers, when the temperature rose to 26°C, were recorded. After temperature change from 13.5° to 26°C, sharp increases occur in the amount of K and Cl in the blood plasma, of H2O in the liver and, if the temperature rise is effected quickly, of muscle H2O content. Substantial reductions were recorded in coefficient of condition and K content of the liver. With a fast rise in temperature, liver Na content decreases sharply at first, but rises again later. After temperature change from 6° to 16°C, Ca increase in blood plasma and (if the temperature is raised slowly), decline in muscle Na content are considerable; drop of liver H2O content is less marked. If the temperature change is effected rapidly, then liver Na content and plasma K diminish initially and, thereafter, rise sharply. In the case of quick temperature change from 16° to 6°C, particularly frequent and marked changes in ion and water contents occur; in most cases adjustment is not complete after 288 h, and the observed variations are often clearly different from those observed in the case of slow temperature change. If temperature is lowered rapidly, the amounts of Na and K in muscle and liver fall and the amount of H2O increases. There is a considerable loss of Na and Cl contents and, after rapid temperature change, also in plasmatic K and Ca contents. The responses of fishes acclimated to 6° and 16°C are compared; at 16°C the coefficient of condition and plasmatic Na, K and Cl contents decrease, and H2O, Na and K contents of the liver increase. The amount of K in the plasma and of H2O, Na and K in the muscle remains unchanged. The stress effect upon ion and water contents during transfer to 6°C is significantly greater during fast than during slow temperature change. The problem of proper differentiation between biological consequences of stress and adaptation phenomena is discussed. Complete adaptation was frequently not attained during the course of our experiments, especially not at low temperatures.  相似文献   

17.
Zostera marina L. was studied at the Izembek Lagoon, Alaska Peninsula. Two morphologically different forms, tidepool and subtidal, can be distinguished. Both show a high tolerance to different salinities and temperatures. The plasmatic resistance was found in a range of distilled H2O up to 3.0 seawater (24 h) and between-6° and 34°C (12 h). Within these resistance limits, the photosynthesis, which has its maximum in normal (1.0) seawater, decreases nearly to zero not only in distilled H2O but even in 2.0 seawater, and increases with the temperature in the tidepool form up to 35°C, but in the subtidal form up to 30°C only. At higher temperatures photosynthesis declines sharply in both forms. Respiration has its minimum in distilled H2O and at 0°C and increases with increasing salinity and temperature.Dedicated to Prof. Dr. Dr. h. c. mult. K. Mothes, Halle, Germany (DDR) on the occasion of his 70th birthday.  相似文献   

18.
Oxyhemocyanin (OxyHc), blood protein, glucose, acylglycerol (AG), and lactate of Litopenaeus vannamei juveniles were investigated. Statistical analyses were done on baseline values for each metabolite and on OxyHc from shrimp cultured in outdoor (20-m2 ponds) and indoor (90-l tanks). The values obtained were compared with blood metabolites reported in the literature for L. vannamei maintained under similar conditions. Normal distribution was only found for samples from indoor shrimp. The distribution values for blood metabolites from shrimp cultured in outdoor ponds and indoor tanks were right or left skewed. OxyHc, blood proteins, and glucose levels were higher in shrimp cultured in outdoor ponds than those observed in shrimp maintained in indoor tanks. These differences were attributed to availability of live food in outdoor culture ponds. The OxyHc/protein ratio showed that 60% of blood protein is OxyHc in outdoor-cultured shrimp and was lower than in indoor-cultured shrimp, and this ratio was lower than that found (97%) in indoor-cultured shrimp. The type of food was identified as a dominant factor affecting blood metabolites. AG in outdoor-cultured shrimp was significantly lower than that observed in indoor-maintained shrimp. Blood lactate concentration of shrimp was not affected by the culture conditions. The blood levels for protein, glucose, and lactate reported here are similar to those reported previously for other crustacean species, indicating that these can be used as a reference for evaluating the physiological status of L. vannamei. When we compared the OxyHc, blood protein, glucose, and lactate levels of L. vannamei juveniles with other crustacean species, we observed that crabs, lobsters (low-activity species), and closed-thelycum shrimp species (mean-activity species) had lower values in comparison to those observed in open-thelycum shrimp species, including L. vannamei juveniles. Possibly the blood metabolites and OxyHc could be reflecting the morphological and physiological adaptation of crustaceans, because these metabolites will depend on energetic demands.  相似文献   

19.
The objective of this study was to determine the influence of natural biowaste substrates such as banana peel powder and coir powder at varying environmental parameters of pH (4-9) and temperature (20-50 degrees C) on the cellulase enzyme production by Aspergillus niger. The cellulase enzyme production was analyzed by measuring the amount of glucose liberated in IU ml(-1) by using the dinitrosalicylic acid assay method. The substrates were pretreated with 1% NaOH (alkaline treatment) and autoclaved. The maximum activity of the enzyme was assayed at varying pH with temperatures being constant and varying temperatures with pH being constant. The highest activity of the enzyme at varying pH was recorded at pH 6 for banana peel powder (0.068 +/- 0.002 IU ml) and coir powder (0.049 +/- 0.002 IU ml(-1)) and the maximum activity of the enzyme at varying temperature was recorded at 35 degrees C for both banana peel powder (0.072 +/- 0.001 IU ml(-1)) and coir powder (0.046 +/- 0.003 IU ml(-1)). At varying temperatures and pH the high level of enzyme production was obtained at 35 degrees C and pH 6 by using both the substrates, respectively. However among the two substrates used for the production of cellulases by Aspergillus niger banana peel powder showed maximum enzymatic activity than coir powder as substrate.  相似文献   

20.
Acrylamide (ACR) exerts its toxicity through stimulation of the oxidative stress; yet, its effect on neurotransmitter catabolic enzymes has not been elucidated. We investigated the effects of ACR exposure on brain and hepatic tissues antioxidant enzymes activities and different markers such as, acetylcholinesterase (AChE), nitric oxide (NO), monoamine oxidase (MAO), and lipid profile, and to evaluate the protective effects of garlic against ACR toxicity. Male Sprague-Dawley rats were exposed to ACR (1 mg kg?1 body weight) with or without diet containing 1.5% of garlic powder for 40 days. ACR administration showed a decrease in AChE activity associated with an increase in MAO activity in both brain and hepatic tissues. In addition, ACR administration increased the lipid peroxidation and NO levels of both tissues while decreased the activities of glutathione (GSH), superoxide dismutase, and glutathione-S-transferase (GST). On the other hand, the activities of glutathione peroxidase (GPx) and catalase activities increased as a consequence of GSH depletion after ACR exposure. Finally, ACR exposure increased the brain and liver lipid profile of cholesterol, triglycerides and total lipid, while phospholipids level was decreased. Coadministration of garlic powder with ACR significantly attenuated oxidative stress, MAO activity, and inflammation in brain and hepatic tissues but did not ameliorate AChE activity. In conclusion, our results emphasized the role of garlic as a potential adjuvant therapy to prevent ACR neurotoxicity and hepatotoxicity.  相似文献   

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