首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
应用RD-PCR技术制备HIV基因芯片探针   总被引:12,自引:2,他引:12  
利用限制性显示 (RD PCR)技术快速分离HIV 1基因片段制备DNA芯片探针 .以Sau3AⅠ酶切HIV基因 ,得到许多大小适合芯片的限制性酶切片段 .然后在片段两端接上接头 ,根据酶切位点、接头的序列设计通用引物 .在该通用引物的 3′端分别延伸一个碱基后 ,通过引物间的两两组合 ,将PCR反应分成 10个亚组 .纯化各组PCR产物 ,克隆到T载体上 .阳性克隆经鉴定、扩大培养后提取质粒 .以质粒为模板扩增靶片段并进行序列分析 .每个亚型得到了十几个 10 0~ 10 0 0bp的HIV基因片段 .研究表明 ,RD PCR技术是一种有效的快速制备基因芯片探针的方法  相似文献   

2.
目的:研究多层螺旋CT对肺结核合并肺癌的鉴别诊断价值。方法:选择2013年3月至2015年9月在我院确诊的肺结核合并肺癌患者32例和单纯肺结核患者39例应用多层螺旋CT扫描患者肺部病变情况。结果:肺结核合并肺癌组:陈旧性肺结核28例、活动性肺结核4例;病灶位置经典部位29例、非经典部位3例,合并鳞癌11例、腺癌13例、小细胞癌5例、未分化癌3例;10例结核病灶与肺癌病灶不同侧、13例结核病灶与肺癌病灶同侧不同叶、9例结核病灶于肺癌病灶同侧同叶。单纯性肺结核组胨旧性肺结核36例、活动性肺结核3例;病灶位置经典部位34例(上叶尖段11例、后段9例、下叶背段14例)、非经典部位5例。肺结核合并肺癌组患者分叶征、毛刺征、胸膜凹陷征、阻塞性肺炎及肺不张以及棘状突起比例高于单纯肺结核组,而空泡影比例低于单纯肺结核组,差异具有统计学意义(P0.05);两组钙化、斑片条索影、结节影以及空洞或空腔比较,差异无统计学意义(P0.05)。结论:多层螺旋CT对肺结核合并肺癌具有较高的临床鉴别诊断价值。  相似文献   

3.
The normal and vacuum uv spectra of cytosine, 5-azacytosine, and 6-azacytosine thin layers were determined. The spectra were resolved into a series of Gaussian bands and the experimental band positions and oscillator strengths were compared with the calculated values. The calculations were carried out with the PPP-SCF-CI method. The agreement of the calculations with those of others and with the experiment is discussed.  相似文献   

4.
Human "O" cells were fixed with pyruvic aldehyde, treated with tannic acid, and fixed with glutaraldehyde. The cells were sensitized with amoeba antigen and stored in a refrigerator. The sensitized cells were used periodically for the indirect hemagglutination test with a battery of sera from patients with intestinal amebiasis and confirmed and unconfirmed amebic liver abscess, and also from negative controls. The same battery was tested with cells sensitized with different batches of antigen and also with fresh sheep cells. None of the cells showed any reaction with negative control sera. The fixed cells remained sensitive and stable throughout the study. Reproducibility of the titers with the fixed cells within each day and from day to day was satisfactory. The titers with fixed human "O" cells were slightly lower than were the titers with fresh sheep cells. The advantages of using stable, sensitized cells are pointed out.  相似文献   

5.
Five populations ofDrosophila melanogaster that had been selected for postponed aging were compared with five control populations using two-dimensional protein gel electrophoresis. The goals of the study were to identify specific proteins associated with postponed aging and to survey the population genetics of the response to selection. A total of 321 proteins were resolvable per population; these proteins were scored according to their intensity. The resulting data were analyzed using resampling, combinatoric, and maximum parsimony methods. The analysis indicated that the populations with postponed aging were different from their controls with respect to specific proteins and with respect to the variation between populations. The populations selected for postponed aging were more heterogeneous between populations than were the control populations. Maximum parsimony trees separate the selected populations, as a group, from their controls, thereby exhibiting a homoplastic pattern.  相似文献   

6.
The primary goal was to compare results from a free-operant procedure with pigeons [Machado, A., Guilhardi, P., 2000. Shifts in the psychometric function and their implications for models of timing. J. Exp. Anal. Behav. 74, 25-54, Experiment 2] with new results obtained with rats. The secondary goal was to compare the results of both experiments with dependent variables that were not used in the original publication. As in the original study with pigeons, rats were trained on a two-alternative free-operant psychophysical procedure in which left lever press responses were reinforced during the first and second quarters of a 60-s trial, and right lever press responses were reinforced during the third and fourth quarters of the trial. The quarters were reinforced according to four independent variable interval (VI) schedules of reinforcement. The VI duration was manipulated in each quarter, and shifts in the psychophysical functions that relate response rate with time since trial onset were measured. The results obtained with rats were consistent with those previously obtained with pigeons. In addition, results not originally reported were also consistent between rats and pigeons, and provided insights into the perception, memory, and decision processes in Scalar Expectancy Theory and Learning-to-Time Theory.  相似文献   

7.
《Biochemical medicine》1978,19(3):395-404
Acidic glycosaminoglycans (AGAG) were extracted from whole human kidney tissues of different aged subjects and were purified by precipitation with cetylpyridinium chloride and by an ion exchange resin column chromatography. The prepared AGAG were individually digested with chondroitinase-AC and they were further digested with chondroitinase-ABC. The resulting unsaturated disaccharides and the undigested AGAG were identified by paper chromatography, electrophoresis, and other chemical analyses. The AGAG, which were resistant to chondroitinase-AC, were mainly heparan sulfates and their proportion to total AGAG appeared to decrease with the advance of age. Dermatan sulfate plus oversulfated dermatan sulfate were composed of one-fifth to one-third of the AGAG resistant to chondroitinase-AC, and their proportion tended to increase with the advance of age.  相似文献   

8.
南美香瓜梨离体培养快速复壮繁殖的研究   总被引:5,自引:0,他引:5  
张云开  朱西儒  张海保  刘卫   《广西植物》1996,16(1):69-72
南美香瓜梨茎段被移植在MS基本培养基上,其中添加有BA6.0(mg/L以下单位相同)、IBA0.2培养4周后增殖到3.8倍。用其嫩叶切块,在含有2,4—D0.5,BA0.25的MS培养基上先诱导形成绿色愈伤组织,然后转入含BA6.0和IBA0.2的MS培养基上,产生丛生不定芽。将2.5~3.0cm的不定芽切下移入含IBA0.5与0.2%活性炭,1/2MS无机盐的培养基上,25天后诱导生根,移栽成活率达90%以上。  相似文献   

9.
The comparative substrate specificities of five purified serine hydrolases from rat liver microsomes have been investigated, especially their action upon natural lipoids. All enzymes had high carboxylesterase activities with simple aliphatic and aromatic esters and thioesters. The broad pH optima were in the range of pH 6-10. Synthetic amides were less potent substrates. The hydrolytic activities towards palmitoyl-CoA and monoacyl glycerols were generally high, whereas phospholipids and palmitoyl carnitine were cleaved at moderate rates. Acetyl-CoA, acetyl carnitine, and ceramides were not cleaved at all. The closely related hydrolases with the highest isoelectric points (pI 6.2 and 6.4) were most active with palmitoyl-CoA and palmitoyl glycerol. One of these enzymes might also be responsible for the low cholesterol oleate-hydrolyzing capacity of rat liver microsomes. Among the other hydrolases, that with pI 6.0 showed significant activities with simple butyric acid esters, 1-octanoyl glycerol, and octanoylamide. The esterase with pI 5.6 had the relatively highest activities with palmitoyl carnitine and lysophospholipids. The purified enzyme with pI 5.2 showed some features of the esterase pI 5.6, but generally had lower specific activities, except with 4-nitrophenyl acetate. The lipoid substrates competitively inhibited the arylesterase activity of the enzymes. The varying activities of the individual hydrolases were influenced in parallel by a variety of inhibitors, indicating that the purified hydrolases possessed a relatively broad specificity and were not mixtures of more specific enzymes. The nomenclature of the purified hydrolases is discussed.  相似文献   

10.
目的制备兔抗16种鸟类的二级抗体,并进行辣根过氧化物酶标记,为鸟类血清学检测系统的建立提供工具。方法采用水稀释法粗纯抗体后,再利用改良的饱和硫酸铵分级沉淀法,或亲和层析结合饱和硫酸铵沉淀法,或饱和硫酸铵沉淀法结合SDS-PAGE凝胶切胶纯化的方法进一步纯化鸟类的IgY,利用纯化的IgY免疫大耳白兔制备抗血清,用免疫双扩散来检测抗血清的效价,并用Protein A亲和层析的方法来纯化兔抗鸟类的二级抗体,采用简易过碘酸钠法对纯化的兔抗鸟类的二级抗体进行辣根过氧化物酶标记,通过ELISA方法测定标记抗体的效价,并利用Western blots考察标记抗体的特异性。结果纯化了灰雁、鸬鹚、鸵鸟、小鹈、鸽子、鹅、孔雀、鹌鹑、贵妃鸡、草鹭、夜鹭、赤嘴潜鸭、燕鸥、长脚鹬、虎皮鹦鹉、翘鼻麻鸭等16种鸟类的IgY,免疫双扩散法测定兔抗这16种鸟类的抗血清效价均达到1∶32,并对纯化的兔抗灰雁IgY、兔抗鸬鹚IgY、兔抗鸵鸟IgY、兔抗小鹈IgY、兔抗鸽子IgY、兔抗鹅IgY、兔抗孔雀IgY、兔抗鹌鹑IgY、兔抗贵妃鸡IgY、兔抗草鹭IgY、兔抗夜鹭IgY、兔抗赤嘴潜鸭IgY、兔抗燕鸥IgY、兔抗长脚鹬IgY、兔抗虎皮鹦鹉IgY、兔抗翘鼻麻鸭IgY等16种兔抗鸟类IgY的二级抗体进行了辣根过氧化物酶标记,ELISA测定标记抗体的效价达到1∶800~80000左右,Western blots显示标记抗体具有很好的特异性。结论成功制备了辣根过氧化物酶标记的兔抗16种鸟类的二级抗体,为鸟类血清学检测体系的建立提供了工具。  相似文献   

11.
流感病毒血凝素基因,神经氨酸酶基因免疫BALB/c小鼠,获得特异阳性抗体反应,抗体滴度与基因免疫量呈正相关性,各实验组免疫小鼠抗同型流感病毒攻击存活率为100%,血凝素基因免疫小鼠抗异型流感病毒攻击存活率为100%,神经氨酸酶基因免疫小鼠抗异型流感病毒攻击存活率为75%,血凝素基因与神经氨酸酶基因联合免疫小鼠抗异型流感病毒攻击存活率为100%。  相似文献   

12.
Carstem Humlum 《Ecography》1981,4(4):238-244
Age distributions and fruit production of populations of Oxyria digyna (L) Hill were studied in Norway and Greenland. The observed age distributions were described by the negative exponential function and by the power function. Three kinds of distributions were observed: steep, flat and bell-shaped with the corresponding hint production: 33–917, 8–108 and 76–303 fruits per individual. The population with the steep age distributions and high fruit productions were assumed to be increasing. They were found in sites with almost no vegetation (≤10% cover). The populations with the flat age distributions and the low fruit production were assumed to be stable. They were found in sites with a vegetational cover of 50–75%. The populations with the bell-shaped age distributions and the intermediate fruit productions were assumed to be decreasing. They were found in sites with a closed vegetation (cover ≥100%).  相似文献   

13.
本实验研究了SVDV在微细胞和微胞质体两种非完整细胞体系内的复制。用秋水仙素处理IB-RS-2细胞,在含有松胞素B的Ficoll 400不连续梯度中进行高速离心,制备了大量的微细胞。微细胞在正常的培养条件下60小时后仍有70%以上存活,用SVDV感染只需4—5小时就几乎全部脱落。并证明微细胞能繁殖出有感染力的子代病毒。用松胞素B去核技术制备的微胞质体,运用扫描电镜和显微放射自显影的方法证实了SVDV可以在微胞质体内复制病毒RNA,并引起微胞质体病变。同时纯化了用松胞素B处理悬浮的IB-RS-2细胞而制备的大量的微胞质体,SVDV感染后,可以产生一定数量的有感染力的子代病毒。虽然滴度低于完整细胞繁殖的病毒,但证明了SVDV可以利用微胞质体中少量的细胞成分和酶类完成其感染、复制和装配一系列繁殖过程,产生有感染力的子代病毒。  相似文献   

14.
The aim of this work was to differentiate patients with essential tremor from patients with Parkinson’s disease. Electromyographic data from biceps brachii muscles and kinematic data from arms during isometric tension of the arms were measured from 17 patients with essential tremor, 35 patients with Parkinson’s disease and 40 healthy controls.The EMG signals were divided to smaller segments from which histograms were calculated. The histogram shape was analysed with a feature dimension reduction method, the principal component analysis, and the shape parameters were used to differentiate between different subject groups. Three parameters, RMS-amplitude, sample entropy and peak frequency were determined from the kinematic measurements of the arms.The height and the side differences of the histogram were the most effective for differentiating between essential tremor and Parkinson’s disease groups. The histogram parameters of patients with essential tremor were more similar to patients with Parkinson’s disease than healthy controls. With this method it was possible to discriminate 13/17 patients with essential tremor from 26/35 patients with Parkinson’s disease and 14/17 patients with essential tremor from 29/40 healthy controls. The kinematic parameters of patients with essential tremor were closer to parameters of patients with Parkinson’s disease compared to healthy controls. Combining EMG and kinematic analysis did not increase discrimination efficiency but provided more reliability to the discrimination of subject groups.  相似文献   

15.
C Netley  W B Hanley  H L Rudner 《CMAJ》1984,131(7):751-755
The age at diagnosis, dietary treatment and intelligence quotient (IQ) of 119 patients with phenylketonuria (PKU) and its variants who were under long-term observation were studied. In 27 of the 79 patients with classic PKU the diagnosis had been made and treatment begun late (after 2 months of age). The mean IQ of these 27 patients was 57.6 when they were in their early 20s (although 2 had normal IQs). In contrast, among the 52 patients with classic PKU who were not treated late the mean IQ was 93.6 for the 27 who were still receiving dietary therapy. The mean IQs were 99.3 and 92.7 at ages 5 (when the diet was discontinued) and 15 years respectively for the 12 who had been treated "adequately". It was 76.0 for the 13 who were "over-treated" (malnourished) in the first 6 months of life. Among the patients with atypical PKU, who were treated early, the mean IQs were 110.0 for the 7 who were still receiving dietary therapy and 102.7 for the 12 who were not. The 21 patients with persistent benign hyperphenylalaninemia, who were not treated, had a mean IQ of 104.2. The most important factor in the ultimate IQ of patients with classic PKU is very early diagnosis (by 2 weeks of age) along with immediate initiation of dietary therapy.  相似文献   

16.
目的 联合采用表达谱芯片和下一代测序技术同时高通量筛选先天性心脏病胎儿心肌组织表达差异的miRNA.方法 实验组为孕中期先天性畸形胎儿,对照组为同胎龄无心脏畸形的难免流产的胎儿,取胎儿心室心肌组织,联合采用Agilent Human 2.0 microRNAs表达谱芯片和SOLiD下一代测序技术同时观察心肌组织microRNA的表达变化,数据采用生物信息学方法进行分析,并用实时PCR方法验证芯片结果.结果 通过差异miRNA筛选,发现先天性心脏畸形组在表达谱芯片和下一代测序中共同差异的24个miRNA,生物信息学预测到1 606个靶基因,靶基因Gene Ontology分析表明其中与细胞进程、代谢过程、生物调控相关的靶基因为主,Pathway显著性分析表明,部分靶基因为生物信号通路中的关键因子;随机挑选共同表达差异的4个miRNA进行验证,结果表明定量PCR检测结果与芯片与下一代测序共同筛选结果基本相符.结论 这些在先天性心脏病中异常表达的miRNA为研究先天性心脏病分子水平上的发病机制提供了重要的线索,将有可能为心脏相关疾病的诊断和治疗提供新的靶点和研发新的药物.  相似文献   

17.
Summary The ovary of the liver fluke has been studied with light and electron microscopy. The organ consisted of germ cells and a layer of peripheral cells suggested to be nurse cells, and was surrounded by a capsule containing muscular tissue. The peripheral cells rested on a thick basement membrane and were irregular in outline. Their nuclei were of irregular shape, the mitochondria were dark with few cristae and the endoplasmic reticulum was tubular or vesicular and partly studded with ribosomes. The germ cells were rounded or polyhedral except in the outer part of the ovary where some of them showed irregular processes. The germ cells of the outer region (oogonia) were relatively small and in close contact with the cells suggested to be nurse cells. The inner germ cells (oocytes) were large and loosely packed. Their nuclei were irregular and contained round distinct nucleoli. The nuclear envelopes showed numerous pores. The endoplasmic reticulum was very sparse, but free ribosomes were abundant in the cytoplasm. This corresponded with a strong basophilia removable with RNase. In addition round basophilic bodies formed by densely packed ribosomes and membraneous material occurred in close spatial relation to mitochondria. The latter contained dense granules and few cristae. Groups of vesicles and membraneous lamellae were found in the cytoplasm, but they were considerably smaller than vertebrate Golgi complexes. Numerous dense spherical granules were found mainly in the periphery of the large germ cells. The granules were strongly osmiophilic except in the terminal part of the ovary. They were PAS-positive, but negative to Sudan dyes.Supported by a grant from Jordbrukets Forskningsråd, Stockholm.  相似文献   

18.
Antibodies which bind beta2-glycoprotein I (beta2GPI) are associated with antiphospholipid syndrome. Synthetic peptide mimotopes have been discovered which compete with beta2GPI for binding to selected anti-beta2GPI. A thiol-containing linker was attached to the N-terminus of two cyclic thioether peptide mimotopes, peptides 1a and 1b. The resulting peptides, with linker attached, were reacted with two different haloacetylated platforms to prepare four tetravalent peptide-platform conjugates to be tested as B cell toleragens. The linker-containing peptides were reacted with maleimide-derivatized keyhole limpet hemocyanin (KLH) to provide peptide-KLH conjugates. Peptides 1a and 1b were also modified by acylation with 3-(4'-hydroxyphenyl)propionic acid N-hydroxysuccinimidyl ester. The resulting hydroxyphenyl peptides were radioiodinated and used to measure anti-peptide antibody levels. The KLH conjugates were used to immunize mice to generate an anti-peptide immune response. The immunized mice were treated with the conjugates or saline solution and boosted with the appropriate peptide-KLH conjugate. Three of the four conjugates suppressed the formation of anti-peptide antibody. The stabilities of the conjugates in mouse serum were measured, and the relative stabilities did not correlate with ability to suppress antibody formation.  相似文献   

19.
Two types of virus-like particles were observed in the cytoplasm of hemocytes of the bean leaf beetle, Cerotoma trifurcata. The polyhedral particles were 37–40 nm in diameter and were usually in a crystalline array. They were often associated with granular and laminated structures. The enveloped, spherical particles were 70–75 nm in diameter and were composed of three parts: an outer envelope, a central electron-dense core, and an electron-lucent space between the envelope and the central core. The envelope was similar in structure to the membranes of the cell organelles. These particles were also associated with granular and filamentous structures which were distinct from those associated with the nonenveloped, smaller, polyhedral particles. The nonenveloped particles were recovered in large amounts from partially purified preparations from beetles that contained the particles in thin sections and from soybean loopers, Pseudoplusia includens, which were injected with partially purified preparations from beetles.  相似文献   

20.
Experiments were performed to compare the composition and nutritive value of mixtures containing leaf protein coagulum from lucerne with cereals (ground barley, ground wheat and wheat bran), with non-processed cereals alone or with the addition of separately-dried leaf protein. The chemical composition of mixtures and amino acid composition of their proteins were determined by conventional methods. The biological value and true digestibility of cereals and mixture proteins were determined on rats by the Thomas-Mitchell balance method.The biological values of mixture proteins were higher, but their digestibility was lower, than those of cereals alone. Generally, better results were obtained when cereals were mixed with separately-dried leaf protein and with barley rather than wheat.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号