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1.
采用DNase消化法从大鼠肝染色质分离得到富有转录活性的DNA(sDNA)。sDNA琼脂糖凝胶电泳,在0.5—6Kb范围内背景有一片荧光,小于1Kb范围内,出现明显区带。sDNA为探针与大鼠正常肝核RNA杂交百分数(29.5%),为以总核DNA为探针杂交百分数(8.2%)的3.6倍,并高于sDNA与大鼠肝癌核RNA杂交百分数(16.4%).  相似文献   

2.
2015年2月、6月、9月、12月对流溪河21个采样河段底栖无脊椎动物进行了调查。结果表明:4个季节共检出54科95属114种,其中昆虫纲81种,占总数71.05%;软体动物门的腹足纲、瓣鳃纲共23种,占总数20.18%;蛭纲、寡毛纲和甲壳纲等10种,占总数的8.77%。根据6个参照点和15个受损点的底栖动物数据,对21个生物指数进行分布范围、判别能力和Pearson相关性分析,确定流溪河底栖动物完整性指数(B-IBI)指标体系,该体系由多样性指数、EPT分类单元数、摇蚊百分数、颤蚓百分数、敏感类群分类单元数和耐污类群百分数构成。采用比值法计算各生物指数并对各指数值加和得到B-IBI指数值。评价结果表明:在21个河段中,5个为健康,3个为亚健康,10个健康评价为一般,3个较差;总体来看,流溪河处于一般的健康状态;流溪河上游(桂峰水、石坝河、吕田河)等源头支流处于相对健康状态;干流中下游、牛栏河及其他多处支流水质一般或较差。分析表明:上述方法适用于评价流溪河水质健康,可用该方法进行长期监测评价;人类活动程度对底栖动物群落结构影响较大。  相似文献   

3.
1992年9月,我园有一笼舍的7只幼年绿孔雀发生禽痘病。在相邻的笼舍里分别关养有16只成年孔雀和一些禽类动物。当1只幼孔雀初病时,出现食欲减退,羽毛蓬乱,2天后在冠、嘴角、眼结膜上出现突起的圆斑,继之变为绿豆样痘疹,触有坚硬感。病初认为可能系蚊咬所  相似文献   

4.
酿酒酵母BD101菌株的金属硫蛋白能清除羟基自由基。含金属硫蛋白的酵母菌有拮抗60Coγ射线的作用。用计数血液中血小板(PLT)、白细胞(WBC)变化来研究酵母Cu-MT在小鼠γ射线损伤中的作用。结果表明,该菌Cu-MT对PLT降低的改善和回升有作用。但未观察到其对WBC总数变化的影响。提示酿酒酵母Cu-Mr在临床放射病治疗和放疗后抗出血方面有良好的应用前景。  相似文献   

5.
目的:观察实验性重症减压病兔血液细胞计数的变化,分析重症减压病的致死机制。方法:检测加压前、高压停留中、减压后兔血液白细胞(WBC)总数、中性粒细胞、淋巴细胞及血小板(PLT)计数。比较存活动物与死亡动物以上指标变化的特点。结果:6只存活且观察24 h后未遗留任何减压病症状。0.55 MPa下停留30 min后,兔WBC总数由(9.76±2.23)×109/L降至(8.15±2.20)×109/L,而减压后,则增加至(13.14±4.75)×109/L。加压前,死亡动物血液WBC总数为(11.13±2.37)×109/L,明显高于存活动物(8.87±2.11)×109/L,且以中性粒细胞为主。结论:高压下停留可造成兔血液中淋巴细胞数的下降,而快速减压则引起WBC升高和PLT下降。加压前WBC总数高,减压过程PLT减少量大的动物死于重症减压病的可能性更大。  相似文献   

6.
孔雀微卫星引物筛选及其遗传多样性分析   总被引:10,自引:0,他引:10  
包文斌  陈国宏  束婧婷  徐琪  李慧芳 《遗传》2006,28(10):1242-1246
利用29对鸡微卫星标记对孔雀基因组DNA进行种间扩增, 发现14对引物能扩增出特异性条带, 每对引物扩增的平均等位基因数为1.71, 有7对引物具有较丰富的多态性, 其中MCW0080和MCW0098最为理想。蓝孔雀和绿孔雀群体间和群体内的遗传分析结果表明, 绿孔雀和蓝孔雀两个群体的期望杂合度分别为0.7422和0.6943, 群体间的遗传分化系数为0.078, Reynolds’遗传距离和基因流分别为0.0603和3.896, 结果显示这两个孔雀群体的杂合度和遗传多样性水平都很低, 且有相互混杂的趋势。  相似文献   

7.
酵母金属硫蛋白对酵母和小鼠抗γ射线损伤的作用   总被引:1,自引:0,他引:1  
酿酒酵母BD101菌株的金属硫蛋白能清除羟基自由基。含金属硫蛋白的酵母菌有拮抗60Coγ射线的作用。用计数血液中血小板(PLT)、白细胞(WBC)变化来研究酵母Cu-MT在小鼠γ射线损伤中的作用。结果表明,该菌Cu-MT对PLT降低的改善和回升有作用。但未观察到其对WBC总数变化的影响。提示酿酒酵母Cu-MT在临床放射病治疗和放疗后抗出血方面有良好的应用前景。  相似文献   

8.
吴金  张朝晖  王智慧 《植物研究》2020,40(4):481-489
喀斯特天坑微环境对植物结构特征有显著的影响。采用扫描电子显微镜,探究孔雀藓属蒴齿在喀斯特天坑内的亚显微结构,旨在为微环境下藓类植物蒴齿结构特征研究提供参考。研究结果表明:①基于蒴齿的亚显微形态研究,孔雀藓属两个种,即黄边孔雀藓(Hypopterygium flavo-limbatum C.Muell)、东亚孔雀藓(Hypopterygium japonicum Mitt)蒴齿双齿层,内外齿层数均为16枚,外齿层背面均具"Z"字形的中脊,齿片形态、曲向、外齿层背侧脊纹、齿条腹侧横纹以及是否具节瘤具有明显的差异,属于稳定性特征,可作为系统分类的依据;而齿片长度、宽度、节片数、横脊数、中脊数,属于可变性特征,受环境因子的影响,在运用藓类植物蒴齿作为系统分类依据时应作性状的筛选。②光照度、空气温度、空气湿度以及海拔是影响天坑内黄边孔雀藓(H.flavo-limbatum)蒴齿形态结构发育生长的主要环境因子,空气湿度、光照度以及人为干扰度是影响天坑内东亚孔雀藓(H.japonicum)蒴齿形态结构发育生长的主要环境因子。两种孔雀藓属植物蒴齿结构受湿度的影响最大,其生境多为湿度大、土壤含水量丰富的环境。  相似文献   

9.
目的探讨葛根芩连汤对肠道湿热证泄泻小鼠肠道微生物的影响。方法造模:10只KM雄性小鼠随机分为正常组5只和模型组5只,采用"高糖高脂+高温高湿+白酒复合灌胃冰水"的方法制备肠道湿热证泄泻小鼠模型。治疗:15只KM雄性小鼠随机分为正常组5只和模型组10只,造模成功后将模型组小鼠分为自愈组和治疗组,治疗组小鼠运用葛根芩连汤进行治疗,分别在造模和治疗后无菌采集小鼠肠道内容物进行微生物培养。结果造模后,小鼠出现懒动、肛温升高、体重增长缓慢、黄褐色稀便、肛门污秽等湿热泄泻症状,肠道乳杆菌数高于正常组,而细菌总数、肠杆菌、双歧杆菌、B/E值降低,其中细菌总数以及双歧杆菌数与正常组相比差异有统计学意义(t=14.182,P0.001;t=2.797,P=0.049)。经葛根芩连汤治疗后,小鼠肠道乳杆菌和双歧杆菌数高于正常组,而细菌总数、肠杆菌数低于正常组,且乳杆菌数和肠杆菌数与正常组相比差异有统计学意义(t=-5.210,P=0.033;t=-11.160,P=0.008),B/E值与正常组差异无统计学意义(t=-1.427,P=0.227)。结论造模使小鼠肠道双歧杆菌数显著降低,B/E值下降;葛根芩连汤可促进肠道湿热证泄泻小鼠肠道乳杆菌和双歧杆菌的增生,提高B/E值。  相似文献   

10.
大黄中蒽醌衍生物在体内可进行氧化和結合代謝,其代謝途徑可能如下: 小鼠分別口服大黄酸、芦薈大黄素和大黄酚,24小时尿中总蒽醌衍生物排出量(剂量的百分数)分别为27%、14%和6%。人体口服大黄酚,尿中蒽醌衍生物的排出率以4—12小时为最高,不同时間間隔,尿中蒽醌衍生物轉化产物所占百分数没有显著差异。文中詳細討論到蒽醌衍生物在体内的代謝轉化与药物的“油”/水分配系数、pK_α值、排出量、尿液的pH以及药理活性等有密切关系。  相似文献   

11.
This study compared the relationship between isokinetic lifting test (ILT) performance and a maximal operational lifting test (OLT) with that between an isoinertial progressive lifting test (PLT) and OLT. Fifty subjects performed the ILT, PLT and OLT after familiarization trials. OLT was defined as the weight of the heaviest crate that could be lifted to 1.34 m with a progressive, incremental test. ILT performance was the force generated during a single maximal simulated lift on an isokinetic dynamometer. PLT performance was the maximal weight lifted to 1.52 m with a progressive, incremental protocol on a weight stack. OLT was highly correlated with ILT (r = 0.96) and PLT (r = 0.97); the standard error was similar for both linear regression equations. The results demonstrate that a single maximal voluntary lift on an isokinetic dynamometer is as good a predictor of OLT as in the PLT presently used in military recruit centers.  相似文献   

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Recent advances support an important role for NK cells in determining immune responses beyond their cytolytic functions, which is supported by their capacity to secrete several cytokines and chemokines. In particular, NK-derived IFN-gamma has proven to be fundamental in shaping adaptive immune responses. Although the role of inhibitory NK receptors (iNKR) in the regulation of cytotoxicity has been widely explored, their involvement in the control of cytokine production has been scarcely analyzed. Specifically, no data are available referring to the role of the iNKR ILT2/CD85j in the regulation of IFN-gamma secretion by NK cells. Published data support a differential regulation of cytotoxicity and cytokine expression. Thus, formal proof of the involvement of HLA class I in regulating the production of cytokines through binding to ILT2/CD85j has been missing. We have determined the response of human NK-92 and primary human ILT2/CD85j(+) NK cells from healthy donors to target cells expressing or not HLA class I. We found specificities of HLA class I-mediated inhibition of IFN-gamma mRNA expression, protein production, and secretion consistent with the specific recognition by ILT2/CD85j. We also found inhibition of IFN-gamma production by ILT2/CD85j(+) T cells in response to superantigen stimulation. Furthermore, ligation of ILT2/CD85j inhibited the production of IFN-gamma in response to poly(I:C), and blocking of ILT2/CD85j-HLA class I interactions increased the secretion of IFN-gamma in NK/immature dendritic cell cocultures. The data support a role for self HLA class I in the regulation of IFN-gamma secretion at the mRNA and protein levels by interacting with the iNKR ILT2/CD85j.  相似文献   

14.
野生与笼养绿孔雀种群的随机扩增多态DNA研究   总被引:5,自引:1,他引:4  
常弘  柯亚永  苏应娟  张国萍  朱世杰 《遗传》2002,24(3):271-274
利用随机扩增多态DNA(RAPD)技术对野生14只和笼养18只绿孔雀(Pavo muticus)个体进行了种群遗传多样性分析。用23个随机引物,野生与笼养绿孔雀分别获得161和166个扩增片段,计算发现野生与笼养绿孔雀的种群内平均相对遗传距离分别是0.0555和0.1355,两种群间的为0.1635;两种群的Shannon多样性指数平均分别是0.4348和1.0163,有显著性差异。以上分析都显示野生绿孔雀的遗传多样性很低。用UPGMA法聚类显示两个种群都是分别来源于两个家系,可据此进行繁育管理。 Abstract:Random-amplified polymorphic DNA(RAPD) was used to investigate the genetic diversity of the population of 14 wild green peafowl and 18 captive green peafowl(pavo muticus).Total of 161 and 166 bands were obtained respectively,and 23 random primers were used to amplify the genomic DNA of the wild and captive green peafowls.The average relative hereditary distance of the wild and captive green peafowls is 0.0555 and 0.1355 respectively;and the Shannon diversity index is 0.4348 and 1.0163 respectively.There is a prominent differentia between the two populations by T-Test of HO.All the analyses above show that the genetic diversity is very low in wild green peafowl.It tells us that the two populations come from two families by using UPGMA,which can be useful in the breeding management in the future.  相似文献   

15.
Recent numerical studies of abdominal aortic aneurysm (AAA) suggest that intraluminal thrombus (ILT) may reduce the stress loading on the aneurysmal wall. Detailed fluid structure interaction (FSI) in the presence and absence of ILT may help predict AAA rupture risk better. Two patients, with varied AAA geometries and ILT structures, were studied and compared in detail. The patient specific 3D geometries were reconstructed from CT scans, and uncoupled FSI approach was applied. Complex flow trajectories within the AAA lumen indicated a viable mechanism for the formation and growth of the ILT. The resulting magnitude and location of the peak wall stresses was dependent on the shape of the AAA, and the ILT appeared to reduce wall stresses for both patients. Accordingly, the inclusion of ILT in stress analysis of AAA is of importance and would likely increase the accuracy of predicting AAA risk of rupture.  相似文献   

16.
Recent numerical studies of abdominal aortic aneurysm (AAA) suggest that intraluminal thrombus (ILT) may reduce the stress loading on the aneurysmal wall. Detailed fluid structure interaction (FSI) in the presence and absence of ILT may help predict AAA rupture risk better. Two patients, with varied AAA geometries and ILT structures, were studied and compared in detail. The patient specific 3D geometries were reconstructed from CT scans, and uncoupled FSI approach was applied. Complex flow trajectories within the AAA lumen indicated a viable mechanism for the formation and growth of the ILT. The resulting magnitude and location of the peak wall stresses was dependent on the shape of the AAA, and the ILT appeared to reduce wall stresses for both patients. Accordingly, the inclusion of ILT in stress analysis of AAA is of importance and would likely increase the accuracy of predicting AAA risk of rupture.  相似文献   

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