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1.
在真鲷Pagrosomusmajor三倍体诱导研究中,对染色体倍数的分析表明,受精卵受精5min后,在1.5℃冰水中处理5min,可获得17%的三倍体诱导率和28%的嵌合体比率,染色体数分别是:2N=48,3N=7Z,嵌合体50—68。仔鱼红血细胞测量和组织切片分析显示,三倍体和二倍体的红血细胞核直径(长径,下同)、视网膜神经节细胞核直径和中脑细胞核直径大小存在差异,其比率分别是1.42,1.35和1.41,这种差别必然导致三倍体鱼和二倍体鱼在代谢与功能方面的差异。应加强对鱼类三倍体形成机制及应用潜力的研究,同时注意开展其生理学、生化学和行为学的比较研究。  相似文献   
2.
IntroductionEothrocytesedimentahonrateusSR)isanimportantindexofhemorheology.Atpresent,itisdifficulttoachieveaccuracyandcomparabilityinclinicalprachceandresearchbecauseoflackofaunifiedstandardofthereferencevalue(Wintrobe)ofhealthyPeople'sESRinChina.ManyresearchershavemeaSUredthelocalreferencevaluesofESR(Wintrobe)l'-:'l.Bymeansofcorrelationandregressionanalysis,researchontherelationshipbetweenthereferencevalue(Wintrobe)ofESRandgeographicalfactorsshowedthathlereareceylonregularPatternsbet…  相似文献   
3.
SCREENING OF AGGLUTININS IN MARINE ALGAE FROM FUJIAN COAST OF CHINA   总被引:1,自引:0,他引:1  
Thirty-three species of marine algae belonging to Rhodophyta, Phaeophyta and Chlorophyta from the Fujian coast were examined for agglutinins with different animal and human erythrocytes. Protein extracts from 26 species were active against at least one type of the erythrocytes tested. There were 3 species (Grateloupia imbricata, lshigefoliacea and Entermorpha prolifera) whose extracts could agglutinate all the erythrocytes used. The lowest protein concentration required to produce erythrocyte agglutination varied remarkably, from 3.1μg/ml to 500μg/ml . The strongest activity was found in the agglutina-tion of rabbit erythrocytes by Gloiopeltis furcata extract. Inhibition assays performed with nine mono- and bisaccharides indicated that agglutinations of rabbit erythrocytes by extracts of 7 species were inhibited by one or more types of the sugars assayed. The agglutinating activity shown by extracts of most species wasnot affected when the test solution was heated to 90℃, but was lost at 95℃ - 100℃. A few extracts losttheir activity at 60 RS, 65 RS and 75 RS, respectively.  相似文献   
4.
Reference values of erythrocyte sedimentation rate(ESR)are the key to interpret ESR blood test in clinic.The common local reference ESR values are more accuracy in blood test that are established with natural geographical factors by using the multiple linear regression(MLR)model and the artificial neural network(ANN).These knowledge-based methods have limitations since the knowledge domains of ESR and natural geographical factors are limited.This paper presents a new cases-depended model to establish reference ESR values with natural geographical factors and location using case-based reasoning(CBR)since knowledge domain of ESR and geographical factors is weak.Overall 224 local normal ESR values of China that calculated from 13623 samples were obtained,and the corresponding natural geographical factors and location that include altitude,sunshine hours,relative humidity,temperature,precipitation,annual temperature range and annual average wind speed were obtained from the National Geomatics Center of China.CBR was used to predict the unseen local reference ESR values with cases.The average absolute deviation(AAD),mean square error(MSE),prediction accuracy(PA),and Pearson correlation coefficient(r)between the observed and estimated data of proposed model is 33.07%,9.02,66.93% and 0.78,which are better than those of ANN and MLR model.The results show that the proposed model provides higher prediction accuracy than those of the artificial neural network and multiple linear regression models.The predicted values are very close to the observed values.Model results show significant agreement of cases data.Consequently,the model is used to predict the unseen local reference ESR with natural geographical factors and location.In spatial,the highest ESR reference areas are distributed in the southern-western district of China that includes Sichuan,Chongqing,Guangxi and Guizhou provinces,and the reference ESR values are greater than 23 mm/60 min.The higher ESR reference values are distributed in the middle part and northern-eastern of China which include Hubei,Henan,Shaanxi,Shanxi,Jilin and Heilongjiang provinces,and the reference ESR values are greater than 18 mm/60min.The lowest ESR reference values are distributed in the northern-western of China that includes Tibet and Xinjiang,and the reference ESR values are lower than 5 mm/60min.  相似文献   
5.
Twelve species of crustacean from Fujian coast were examined for lectins with different animal erythrocytes. Serum extracts fromall of 12 species showed agglutinating activity against at least two types of the erythrocytes used, which revealed the existence of lectins in these species. There were five species ( Penaeus japonicus, Lophosquilla costata, Charybdis feriatus, Portunus pelagicus, Scylla serrata ) whose serums could agglutinate all the erythrocytes tested. The lowest serum protein concentration required to produce erythrocytes agglutination varied remarkably, ranging from 0.7 μg/mL to 8 080 μg/mL. The strongest activity was shown in the agglutination of rabbit erythrocyte by serum of Penaeus vanaminas. Inhibition assays performed with seven mono- and bisaccharides showed that agglutination of quail erythrocytes by serums of three species (Portunus pelagicus, Scylla serrata and Sesarma sp. ) were not inhibited by any sugars, while others were inhibited by at least three types of sugars. The assay of temperature influence on agglutinating activity showed that only Penaeusjaponicus retained activity when the serum was heated to 90℃, and other serums lost their activity at 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃ for 10 minutes, respectively.  相似文献   
6.
采用Hemacolor染料对泥蚶(Tegillarca granosa)、毛蚶(Scapharca subcrenata)、鲫鱼(Carassiusauranus)、牛蛙(Rana catesbeiana)、中华鳖(Pelodiscus sinensis)等5种水产动物血细胞涂片进行染色,利用光镜和扫描电镜两种方法对5...  相似文献   
7.
银杏叶提取物(EGb761)对红细胞脂质过氧化损伤的影响   总被引:6,自引:0,他引:6  
观察银杏叶提取物(EGb761)对红细胞脂质过氧化损伤的影响,探讨其保护红细胞的机制。以活性氧(H2 O2 )作用于离体的正常红细胞,观察EGb761对红细胞溶血度、红细胞丙二醛含量(MDA)、红细胞超氧化物歧化酶(SOD)和ATP酶(ATPase)活性及红细胞膜骨架结构的影响。结果表明:EGb761能明显降低红细胞溶血度,且随着浓度增加其作用逐渐增强,与对照组比较差异有极显著性(t =4.13~19.41,P <0 .0 5 ,0 .0 0 1) ;EGb761能明显降低红细胞MDA含量,提高其SOD ,ATPase酶活性,与对照组比较差异有极显著性(t =2 .0 2~70 .0 6,P <0 .0 5 ,0 .0 0 1) ;EGb761能降低过氧化损伤对红细胞膜骨架的破坏,保护其完整性。可见EGb761能在膜水平上直接对抗氧自由基引发的红细胞脂质过氧化损伤,保护红细胞及其膜骨架结构。  相似文献   
8.
以健康老年男性血沉参考值为例,收集中国各地用温氏法测定的健康老年男性血沉参考值,运用BP神经网络模拟分析其与地理环境的海拔高度、年日照时数、年平均相对湿度、年平均气温、年降水量等要素间的非线性、复杂性关系特征,通过5层神经网络,经过500次及1 300次自学习建立模拟规则后,用此规则很好地模拟健康老年男性血沉参考值与地理环境的关系。知道中国某地的地理要素, 就可用此模型估算该地区老年男性血沉参考值。人工神经网络预测血沉参考值的模型自动定义具体的结构和参数,减少血沉参考值预测中的人为性,计算方便;同时,通过对不同地理要素的组合,模型可以寻找预测误差最低的地理要素组合关系。  相似文献   
9.
Hemolysin produced by various bacteria,may destroy erythrocyte membranes via a pore-forming mechanism,a deter-gent action,or a lipase activity.Previous to this experiment,the mode of action used by cyanobacterial hemolysin had not been re-ported.To characterize the action mode of hemolysin produced by the wild-type strain of Synechocystis sp.PCC6803,hemolysis of erythrocytes originating from human,mouse,sheep,rabbit and goldfish was studied.The erythrocytes of mouse,sheep and rabbit were sensitive,while those of human and fish were resistant,to this hemolysin.Using rabbit erythrocytes,it was shown that hemoly-sis occurred in two steps:a binding step within the first 10 min of treatment and a lytic step after 30 min.Both binding and lysis were highly temperature-dependent.Effects of erythrocyte density on hemolysis suggest that the hemolysin might target erythrocytes via a multiple-hit mechanism.In the osmotic protection experiment,all tested osmotic protectants,with molecular diameters ranging from 0.9 ?5.66 nm,failed to effectively inhibit hemolysis.Scanning electron micrographs showed that the hemolysin caused protuberances or echinocytes in rabbit erythrocytes,and then disrupted and ruptured the erythrocytes.Characteristics of hemolysis showed distinct differences from other pore-forming mechanisms,suggesting that this hemolysin might act through a detergent-like or lipase mecha-nism,rather than a pore-forming mechanism.  相似文献   
10.
应用透射电镜技术研究了斜带髭鲷(Hapalogenys nitens)外周血红细胞和血栓细胞的超微结构。结果表明:红细胞呈卵圆形或长椭圆形,胞核居中,异染色质呈斑块状分布;胞质中含有线粒体、多核糖体、小囊泡、高尔基体和边缘带;可见核正处于分裂的细胞或双核细胞,以及凋亡红细胞。血栓细胞形态多样,细胞表面有的无突起,有的有短的突起或长的丝状伪足;胞核位于细胞中央,异染色质呈片状或网状分布;胞质中含有丰富的游离核糖体、微管,少量的粗面内质网、线粒体、致密颗粒和大液泡;由大量空泡和大小不一、形态各异的小管构成的表面相连小管系遍布于胞质中,成为血栓细胞的一个显著特征;偶见血栓细胞以其丝状伪足抱裹异物颗粒的现象。  相似文献   
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