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1.
We report complete sequences of 2 genes of S.flexneri 1a an Indian isolate for the first time. Shigella is causative agent of shigellosis or bacillary dysentery. Genomic library was constructed by shotgun approach. Sequencing was carried out using Big Dye terminator chemistry using ABI 3730 48 capillary DNA analyzer. 170 recombinants were subjected to nucleotide sequencing. Sequence data was analyzed, of these 2 clones showed presence of complete genes out of the total clones sequenced. Annotations were done using various bioinformatics tools. Gene Sfo676 on contig SF21B11, 513 bp long codes for a protein 170 aa long with molecular weight of 18836.5 daltons. The protein is 99 % identical to S. flexneri 2a 301 and not with any other strain of Shigella. It has 7 different sites for phosphorylation, myristoylation and glycosylation. Predicted cellular localization is cytoplasmic membrane. SF0368 is another full-length gene SF0368 on contig SF69C1 is a 312 nucleotide long. It is 103 aa long with molecular weight 11394.0 daltons. Protein is 100% identical to S. flexneri 2a 301 and 99% with S. sonnei strain 046. The gene shows difference when compared with S.sonnei in mono and dinucleotide frequency as well as amino acid composition.  相似文献   

2.
目的:比较中下段食管癌三维适形放射治疗常见的三野照射与四野照射方法的临床物理参数,优化放疗治疗计划。方法:随机选取中下段食管癌患者,采用VARIAN公司Eclipse治疗计划系统。按照ICRU50号报告指导原则勾画靶区,并分别设计三野与四野三维适形治疗计划,PTV所有方向上均放相同的边界5mm。然后利用体积剂量直方图DVH对两种布野方式的治疗计划靶区量分布,危及器官保护等参数进行分析和比较。处方剂量50Gy/25F。结果:两种照射方式靶区剂量分布情况相似,脊髓受照射剂量三野优于四野。在肺V20以及V5指标中,四野照射明显优于三野照射,在肺V30指标上无明显差异。结论:中下段食管癌三维适形放疗中,四野照射在肺V20、V5指标上优于三野照射计划,从预防严重放射性肺损伤角度上具有优势。  相似文献   

3.
葡萄属植物花粉形态的研究   总被引:2,自引:0,他引:2  
 利用扫描电子显微镜对葡萄属Vitis L.37个类群(包括32种、1亚种和4变种)以及其近缘属麝香 葡萄属Muscadinia(Planch.)Small一种植物的花粉进行了观察,结果表明,葡萄属植物的花粉形态特征 在区别并鉴定属下的种类时有较大价值,但对种以上的分类以及研究系统演化无多大意义。葡萄属植 物的花粉形态特征可以分为4类:(1)花粉粒扁球形或圆球形(P/E值为O.97-1.08),沟较宽,可见被有 较密颗粒状突起的沟膜,属于该类的有紫葛V.coignetiae Pull.ex Planch.;(2)花粉粒长球形至近长圆球 形(P/E值为1.25~1.76),沟较宽,可见有较疏颗粒状突起的沟膜,该类型包括了庐山葡萄V.hui Cheng 等共10种1亚种3变种;(3)花粉粒长圆球形(P/E值为1.87~2.1),沟边缘紧靠合呈直线状,但在赤道 轴萌发孔处沟边缘分开呈菱形,该类型有秋葡萄V.romanetii Roman du Caill.ex Planch.和锈毛刺葡萄V. davidii(Roman du Caill.)Foex.var.ferruginea Merr.et Chun等1种1变种;(4)花粉粒长球形或超长球形 (P/E值为1.30~2.0),沟边缘紧靠成直线状,麝香葡萄Muscadinia rotundifolia(Michx .)Small等21种的花粉属于此类型。  相似文献   

4.
There is an increasing interest to understand the molecular basis of high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) subfractions and their association with coronary artery disease (CAD). The formation of these subfractions is greatly influenced by hepatic lipase (HL) and cholesteryl ester transfer protein (CETP) enzymes. To identify genetic markers influencing LDL and HDL subfractions and their role in CAD we performed a case–control genetic association study on 117 healthy controls and 119 angiographically verified CAD patients. Biochemical analysis was performed using standard assays. HDL-C and LDL-C subfractions were estimated using precipitation methods. Genotyping of C-514T (rs1800588) in the LIPC gene for HL and I405V (rs5882) in the CETP gene was done using PCR-based restriction enzyme analysis and sequencing. Both the polymorphisms were not associated with CAD. The C-514T was associated with increased HDL3-C levels in controls (P = 0.049). The I405V polymorphism was found to be associated with low levels of small dense, LDL (P = 0.038). A multiple regression analysis showed that the effects were dependent on gender and triglyceride levels. We conclude that these polymorphisms are not associated with CAD but are important determinants of HDL-C and small dense LDL particles in our population.  相似文献   

5.
Chylomicrons and very low density lipoproteins (VLDL) are the major carriers of triglycerides (TG) in the plasma. Hypertriglyceridemia (HTG) which is characterized by elevated plasma TG can occur either by overproduction of VLDL triglycerides or lipoprotein particles, by the impaired catabolism of triglyceride-rich lipoproteins or a combined defect in TG metabolism. These abnormalities can result from primary (genetic) disorders or innumerable secondary effects (diet or disease). Primary causes of HTG include the familial hyperlipoproteinemias, types I,IIb, III, IV and V respectively. Secondary effects can arise due to carbohydrate, alcohol or diabetes induced HTG, obesity, chronic renal failure, nephrotic syndrome, excessive stress and trauma. Structural abnormalities and the consequent receptor mediated pathways in foam cell generation are discussed.  相似文献   

6.
对国产荚蒾属Viburnum Linn.植物花粉的光学显微镜及扫描电镜观察表明:1.花粉特征在组间的分类学意义不大,而在组内的每一种都具各自的花粉特征。2.表面纹饰类型包括(1)外壁具半覆盖层,网状纹饰,网脊光滑;(2)外壁具半覆盖层,网状纹饰,网脊上具瘤状突起;(3)外壁无覆盖层或部分成半覆盖层,具鼓锤状基柱或基柱网,基柱顶端具瘤状突起。3.沟类型包括:(1)沟沿处外壁无覆盖层;(2)沟沿处外壁具半覆盖层,网状纹饰;(3)沟沿处外壁具覆盖层;(4)在一极形成合沟。内孔类型包括(1)看不见明显的孔膜;(2)孔膜半球状,与外壁不连续;(3)孔膜半球状,与外壁相连续;(4)孔膜半椭圆球状,纵长;(5)孔膜半椭圆球状,横架于沟间而类似于桥。文中同时对若干组内分类学问题进行了探讨。  相似文献   

7.
研究了真空扩散烧结法在H13钢表面上制备碳化物基金属陶瓷覆层的组织历陛能,论述了烧结工艺对覆层显微组织的影响,分析了覆层与钢基底界面形成特最、覆层的微观硬度分布。结果表明,在1220-1280℃下反应烧结,可获得厚度为1-2mm的碳化物基金属陶瓷覆层,覆层和钢基底通过Fe、Cr、Ni、Mo、V相互扩散渗透产生牢固结合硬度达到980HV,有利于提高钢的耐磨性能。  相似文献   

8.
针对传统消费造成的资源过度消耗与环境严重退化的现象,基于扩展的Solow模型框架,引入环境资源存量约束与绿色消费变量,建立了环境资源约束下以社会福利最大化为目标的绿色消费路径模型,运用最优控制理论得到了均衡状态下最优消费路径的解析解,对不同影响因素变动下最优的绿色消费路径进行数值仿真,结果表明:(1)不同的绿色消费初值影响着消费模式绿色化的速度,但无法实现完全绿色化,两种消费模式之间会最终达到均衡状态;(2)环境资源承载力较高的条件下有利于消费模式的绿色化,但也刺激了传统消费更快速度的增长,从而会降低整体消费的绿色程度;(3)高资本弹性和高环境自净力均不利于消费模式的绿色化。  相似文献   

9.
The present study was carried out to explore the altered lipid, lipoprotein and apoprotein abnormalities along with lipoprotein (a) in chronic kidney disease patients with stage I to V which were further divided into group 1 (stage I and II), group 2 (stage III and IV) and group 3 (stage V). 50 chronic kidney disease patients with stage I to V and 20 healthy normal subjects as controls were recruited for this study. Among the various parameters tested triglyceride levels were high in group 1 and 2, whereas VLDL cholesterol, Lp (a) and apo B levels were significantly high in all the groups when compared to controls (P<0.05). However, LDL cholesterol level was significantly low in group 3 only as compared to control group (P<0.05). Apoprotein AI values also showed significant decrease in all groups as compared to controls (P<0.05). Though total cholesterol levels in group 1 and LDL levels in group 1 and 2 were higher than controls, but the values attained not statistically significant (P>0.05). In conclusion high levels of VLDL cholesterol, Lp (a), apo B and low levels of apoprotein AI as reported in this study are the major lipid disorders in the development of cardiovascular complications at all the stages in these patients.  相似文献   

10.
石蒜属的核型研究   总被引:3,自引:0,他引:3  
本文对石蒜属Lycoris的12个种(包括亚种)和2个人工杂种进行了核型分析。 结果表明,石蒜属植物在染色体数目和核型上存在着较大的变异,而罗伯逊变化、杂交与多倍化是引起染色体变异的主要原因。  相似文献   

11.
 国产苔藓植物的核型研究,目前尚未见到任何报道。本文对中国产绢藓属4种植物进行了核型研究。观察了配子体有丝分裂中期的染色体和异染色体。4种植物的染色体数目均为11。钝叶绢藓(E.obtusatus),密叶绢藓(E.compressus),东亚绢藓(E.okamurae),的核型公式为K(n)=11=2V(H)+2J+6(4v+2i)+m(h),陕西绢藓(E.giraldii)为K(n)=11=2V(H)+V+2J+5(3v+2i)+m(h).4种植物的核型均为首次报道。  相似文献   

12.
本文通过批-柱实验研究低压直流电流对已被NO3-钝化零价铁渗透中零价铁(ZVI)的催化活化,研究发现:加载12V低压直流电流后,阴极附近TCE的去除速率常数比钝化后ZVI的去除效率高出约4倍,低压直流电流可以催化ZVI去除TCE,去除效果的增加和电压成正相关关系;同时,低压直流电流阴极可以活化已经钝化的ZVI,活化后不加载电流时ZVI对TCE的去除效率仍是钝化后ZVI的去除效率的约3倍。经过NO3-钝化后ZVI表面的氧化膜组成以Fe3O4为主;但在加载低压直流电流后,ZVI表面同时会有理α-/β—FeOOH生成,说明低压直流电可能会使Fe3O4溶解还原。  相似文献   

13.
吕红  周密  钱欣  王海涛  林卫平 《科技通报》2012,28(3):105-109,114
为了提高高粘度PVB树脂的缩醛率,本文探讨了聚乙烯醇的浓度,聚乙烯醇与丁醛、盐酸、乳化剂的配比,水/异丙醇混合溶液的比例等对缩醛反应的影响.在优选的工艺条件下,适当比例的水/异丙醇混合溶液不仅能达到溶解法中缩醛率高,缩合分布均匀的优点,而且能保持沉淀法中产品同收、清洗容易的优点,PVB颗粒始终保持大小合适、分布均匀,最佳比值为V(水)∶V(异丙醇)=175∶25,此时缩醛率为81.64%.  相似文献   

14.
秦逸平  袁惠娟 《大众科技》2011,(11):125-127
电动自行车一般由铅酸蓄电池供电,有24V、36V和48V三种规格,但电动车的照明灯、音响、防盗报警器、里程速度显示,电机控制器一般只需12V的直流电压,文章介绍一种基于芯片TL494PWM技术的降压式DC-DC开关电源,通过闭环控制使输出电压稳定,系统具有的过流保护及使系统稳定工作的相位补偿设计都有较好的效果。  相似文献   

15.
In this study, the hot backward extrusion of Ti–6Al–4V alloy is considered by finite element analysis and experiments. The effects of reduction and initial billet temperature on the force required for extrusion, on the maximum strain produced and on the formation of surface cracks are discussed. The simulation results show that the increase of temperature at high reduction is considerable and that can be reached 150 °C in the billet and punch interface. Moreover, the maximum strain is predicted at the interface of billet and punch. The study shows that the temperature rise and plastic deformation may induce surface cracks.  相似文献   

16.
以2008~2017年间CNKI数据库中10本代表性期刊作为数据源,将发表在上述期刊的698篇BIM技术学术论文作为样本,基于文献计量的研究方法并且采用VOSviewer和CiteSpace V两种软件工具进行研究热点与演进趋势分析。研究结果表明信息化、项目管理、深化设计与高层建筑等是国内BIM技术研究的主要热点,演进趋势则沿着管理、功能与应用领域、技术集成3条主线,以期为该领域的后续理论研究与实践应用提供参考和借鉴。  相似文献   

17.
从蒙古香蒲Typha davidiana,宽叶香蒲T.latifolia和长苞香蒲T.angustata花粉中     分别分离得到几个相同的黄酮类化合物。三个为甙元,五个为黄酮醇甙;用薄层层析分析了     五种香蒲花粉(包括上述三种)的黄酮类化合物,结果表明各种花粉黄酮成分基本一致。     从化学上把香蒲属和黑三棱属及可能相关的16个科作了比较,结果表明:香蒲属与露兜     树科相差很远;与帚灯草科,须叶藤科,谷精草科相似;与黑三棱属非常相似;因此建议把香蒲     属和黑三棱属同归于一科——香蒲科,成立香蒲目。该目可能与帚灯草目接近。这些结果与    近来的解剖学、孢粉学、血清学、胚胎学、和细胞学方面的研究结果是一致的。  相似文献   

18.
  Three new combinations, one new synonym, 3 unperfectly known species and 8 distribution maps of 11 species of Chinese and Indo-Chinese Archidendron are pre- sented in this article, as a supplement of the subject “Notes on the genera Archidendron F. V. Mueller and Pithecellobium Martius in Mainland S. E.  Asia” published in Adansonia, ser. 2, 19(1): 3—37. 1979.      I am indebted to prof. Wu, head of Taxonomy laboratory of South China Insti- tute of Botany for translating the article into Chinese and adding some distributivepoints of Chinese species of this genus on the maps.  相似文献   

19.
提出了一种静态的软硬件任务划分与调度相结合的算法,可以同时获得给定任务集在该类平台上的软硬件任务划分和任务调度方案. 算法的时间复杂度为O(V(E+V)+V2logV+PVlogV). 实验结果表明了该算法的可行性和有效性.  相似文献   

20.
Marketing is all about finding out what your customers want and need. The information is used to create the model and improve the quality of products and services to satisfy customers. There are two major parts to a sale's planning: containing sales tactics and sales strategy. To aid in business decision-making, a data warehouse (DW) for sales collects and organizes relevant and historical data. DW is also a method for combining data from various heterogeneous databases (DB) and other sources of information for analysis. In this paper, Information analysis for dynamic Sale planning by AI Decision support process was done. Particle Swarm Optimization (PSO) and Quantum Particle Swarm Optimization (QPSO) algorithms have been used to find optimal MVs for sale planning since several authors prove that these algorithms are better than other existing algorithms. MVs selection is based on three factors: time running of MVs, area of MVs, and access frequency of MVs by manipulating the selection result using a weighted combination of each factor as needed by the designer. For PSO, the most cost of frequency was 1.924 for View (V) 11, while for QPSO, it was 1.722 for V11. For PSO, the most cost of time was 1.931 for V2, while for QPSO, it was 1.221 for V22. For PSO, the most cost of the area was 1.800 for V17, while for QPSO, it was 1.071 for V17. The results revealed that Quantum Particle Swarm Optimization is much more accurate than Particle Swarm Optimization.  相似文献   

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