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排序方式: 共有1839条查询结果,搜索用时 31 毫秒
1.
棉花黄萎病菌毒素结合位点初探 总被引:6,自引:1,他引:5
以纯化的棉花黄萎病菌毒素(PLPC)免疫新西兰白兔制备了PLPC特异性抗血清。将PLPC(15μg·ml 1)用不同浓度的抗体(1~20μg·ml 1IgG)吸附后处理泗棉3号的切根苗,毒素所引起的症状都有不同程度的减轻。表明所制备的抗体在与毒素发生特异性免疫学反应的同时,可部分封闭毒素分子上与毒素受体结合的位点。利用竞争ELISA测定了泗棉3号幼苗子叶的质膜制剂与PLPC的结合活性。结果表明,质膜制剂与毒素结合后能部分阻断毒素与其抗体的免疫学反应,即质膜制剂中含有毒素的结合位点。分别用胰蛋白酶和煮沸处理质膜制剂后,质膜制剂对毒素与其抗体的反应的抑制作用消失,初步表明质膜制剂中与毒素结合的是蛋白质。 相似文献
2.
Total creatine kinase (CK) and CK-MM isoforms were determined in plasma and longissimus dorsi muscle extracts from normal pigs. Based on their total CK activity, the pigs were divided into two groups. Pigs of group 1 (n=16) had a mean plasma total CK of 298±16 U/L and the distribution of the CK-MM isoforms was 65.7±2.5% CK-MM3, 18.9±1.6% CK-MM2 and 15.3±1.5% CK-MM. In group 2 (n=18; 826±75 U/L total CK) four isoforms were observed: 3.1±0.9% CK-MM, 67.9±3.0% CK-MM3, 21.5±2.3% CK-MM2 and 7.5±1.3% CK-MM1. The differences between the two groups of pigs were significant (p<0.001) for CK-MM1 and the presence of CK-MM. Four CK-MM isoforms were also detected in longissimus dorsi muscle homogenates: 45.6±8.1% CK-MM, 32.6±11.7% CK-MM3, 16.6±2.3% CK-MM2 and 5.1±2.8% CK-MM1. The release of CK-MM isoforms from muscle into plasma seems to be unrelated to the concentration of these isoforms in striated muscle. 相似文献
3.
猪血浆蛋白(酶)多态性与杂种优势的关系 总被引:2,自引:0,他引:2
为探讨血浆蛋白 (酶 )多态性与杂种优势的关系 ,测定了杜洛克、长白、大白、杜×长大、大×长大、长×大、大×长共 7个品种 (组合 )的 8个血浆蛋白 (酶 )位点的多态性及部分生长和胴体性状 ,计算了平均基因杂合度与部分经济性状实测值和杂优率的相关关系 .结果表明 ,平均基因杂合度与遗传距离呈正相关 ,与日增重、屠宰率、背膘厚、后腿比例的实测值或杂优率呈正相关 ,与眼肌面积的实测值和杂优率呈负相关 .平均基因杂合度和亲本间遗传距离可为预测杂种优势提供依据 . 相似文献
4.
研究目的在于探讨多巴胺受体激动剂(溴隐停)对地方良种肉鸡繁殖性能的影响。方法从628只28周龄健康的“惠州麻”黄羽肉种鸡群中随机选取1组鸡笼内的40鸡作为实验组,其余的作为对照组。实验组鸡群喂服溴隐停,每只鸡每天1.25mg,连用4d,停用4d后再用4d,对照组不使用。结果在4周的实验期内实验组和对照组的产蛋率分别为83.86%和69.96%;破蛋率分别为1.28%和1.69%,畸形蛋率分别为4.33%和1.19%;实验组平均每只鸡的产蛋总数比对照组多3.89个、合格种蛋数多3.26个;药物处理对平均蛋重无显著影响;使用溴隐停能够提高鸡血液中的雌激素水平。结论溴隐停能够通过抑制地方良种肉鸡体内促乳素的合成与分泌,减少抱窝现象的发生,提高其繁殖性能。 相似文献
5.
F. Atroshi J. Parantainen S. Sankari T. Österman 《Veterinary research communications》1989,13(6):427-433
Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) cocentrations in milk and plasma samples from healthy and mastitic cows were determined by radioi-immunoassay and compared with prostaglandins (PGE2, PGF2 and thromboxane B2 [TXB2]), phospholipids and other relevant parameters in milk and blood. The concentrations of cAMP were about five times higher in plasma (p<0.01) than in milk, whereas the cGMP concentration in milk was three times higher (p<0.01) than that in plasma in both healthy and diseased animals. In mastitic milk, the cAMP and cGMP concentrations were 19% and 65% and in blood plasma 13% and 84% higher respectively than in healthy animals. In milk, cyclic nucleotide concentrations correlated with the markedly elevated cell count and also with the prostaglandin concentration and pH. In blood, cAMP correlated positively with phospholipids and cGMP with reduced glutathione (GSH). These changes are considered to be important in the disease process and, in particular, the increase in cGMP deserves further study. 相似文献
6.
Blood samples were collected every 2 h during a 24 h period from 6 cows of one herd and 10 cows of another herd. In a third herd 9 cows were sampled every 2 h from 6 a.m. to 8 p.m. Concentrations of total bile acids, acetoacetate, glucose and free fatty acids were determined in blood plasma. A marked difference in individual bile acid concentrations and patterns of diurnal variation was found. For most cows the highest bile acid values were observed between 2 and 6 a.m. (overall mean (+/- SD) at 6 a.m.: 104 +/- 84 mumol/l, range: 20-307 mumol/l). Fourteen cows with a bile acid value greater than 90 mumol/l at 6 a.m. ("high BA") were characterized as a group by showing a pronounced decrease in the mean bile acid concentration after morning feeding. In the group of 11 cows with a 6 a.m. bile acid value less than 90 mumol/l ("low BA") the time of day did not contribute significantly to the bile acid variation. For the "high BA" group a nearly synchronous variation between the mean values of the 3 feeding dependent parameters (acetoacetate, glucose and free fatty acids) and the mean values of bile acids was found. The within animal coefficients of correlation between bile acids and the feeding dependent parameters were significantly higher in the "high BA" group than in the "low BA" group. No direct connection was found between bile acid levels and the quantity of concentrates fed or the individual milk yield. 相似文献
7.
Thoresen SI Tverdal A Havre G Morberg H 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):129-133
To assess changes in 24 blood constituents in frozen serum and heparinized plasma, blood samples were drawn from 10 clinically normal German Shepherd army dogs. The storage characteristics of nine enzymes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, lipase), and 15 metabolites and minerals (albumin, bile acids, bilirubin, calcium, cholesterol, creatinine, fructosamine, glucose, magnesium, phosphate, potassium, protein, sodium, triglycerides, urea) were studied. Parallel samples of serum and heparinized plasma were stored for 90 and 240 days at two different storage temperatures, -200 degrees C and -700 degrees C. Sixteen of the 24 analytes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, bile acids, calcium, cholesterol, creatinine, fructosamine, magnesium, phosphate, urea) showed statistically significant (p < 0.05) changes during the storage period related to storage time, storage temperature, and sample type. Seven of the analytes (amylase, GGT, GLDH, LDH, bile acids, fructosamine, magnesium) showed changes of possible clinical importance with mean differences from baseline larger than 20% for the enzymes and 10% for the metabolites and minerals during the storage periods. 相似文献
8.
9.
Takeshi SHINOGI Tomoko SUZUKI Yoshihiro NARUSAKA Pyoyun PARK 《Journal of General Plant Pathology》2002,68(1):38-45
The rapid generation of reactive oxygen species (ROS), called the oxidative burst, is one of the earliest host responses to
pathogen infection or elicitor treatments. Therefore, we looked for the induction of ROS generation in Japanese pear leaves
by the host-specific toxin, AK-toxin I using a cytochemical method for detecting H2O2. A small amount of non-specific generation of H2O2 was found in the cell walls in toxin- and water-treated susceptible and resistant leaves. Thus, the generation of H2O2 at cell walls appears to be caused by wounding stress during sampling. Specific generation of ROS, however, was found only
in the membrane fragments and extended desmotubules characteristic of modified sites of the plasma membrane in the toxin-treated
susceptible leaves. In addition, generation of H2O2 at plasma membranes was observed with higher frequency in toxin-treated susceptible leaves. This result indicates that the
H2O2 generation was associated with damaged sites in the plasmalemma after toxin treatment and perhaps with the formation of membrane
fragments from altered portions of the invaginated plasma membrane.
Received 21 September 2001/ Accepted in revised form 25 October 2001 相似文献
10.
NaCl胁迫下枸杞愈伤组织活性氧产生与质膜H+—ATPase活性的关系 总被引:4,自引:1,他引:4
以枸杞愈伤组织为材料,研究了盐胁迫对活性氧伤害和质膜H -ATPase活性的影响。结果表明,NaCl浓度为100mmol/L时超氧阴离子(O2-·)和过氧化氢(H2O2)含量上升,质膜H -ATPase活性先升后降;质膜相对透性与丙二醛(MDA)含量呈显著正相关;超氧阴离子(O2-·)和过氧化氢(H2O2)含量与质膜H -ATPase活性在重度胁迫下呈显著负相关,说明盐胁迫下活性氧积累可能是加速伤害质膜功能的主要原因之一。 相似文献