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AIM: To compare Fuji intelligent chromo endoscopy and staining techniques in differential diagnosis for colonic tumor and non-tumor lesions.

目的：探讨内镜智能分光比色技术鉴别大肠肿瘤及非肿瘤性病变的价值。

It is demonstrated that the chiral quaternary ammonium salts catalysts exhibit promising catalytic properties for the substrate. Part III: The synthesis and the characterizing of the macroporous aminomethyl resin-supported cinchona alkaloid complexes and the study on its catalytic properties The part consists of two subsections. the macroporous aminomethyl resin -supported cinchona alkaloid complexes were synthesized by the stuff (cinchonine, quinine and macroporous aminomethyl resin). Their structures were characterized by means of elemental analysis, XPS, TG/DTA; the chiral polymer-supported complexes were first used as catalysts for the reduction of ketones. Their catalytic properties for the reduction processes were investigated. The comparison of the products e.e., the conversion of the substrate among different reduction processes was employed with determined by HPLC. The effects of the time, the temperature, the ratio of catalyst to substrate, reaction solvent as well as the recycle times were also discussed.

第三章聚-4-氨甲基苯乙烯负载金鸡纳碱金属络合物的合成与表征及其不对称催化性能研究本章分为两节，以辛可宁和奎宁及聚-4-氨甲基苯乙烯为原料，合成了4种聚-4-氨甲基苯乙烯负载金鸡纳碱络合物催化剂，并对它们的结构用元素分析、X-射线光电子能谱、TG/DTA等几种测试手段进行了表征；首次将所合成的手性高分子负载的金属络合物用于催化芳香酮不对称还原反应，详细研究了所得的手性高分子负载的金属络合物对不同底物的催化性能，用HPLC等分析手段定量检测了还原过程的底物转化率及其产物对映异构体选择性，并考察了反应时间、反应温度、催化剂和底物投料比、反应溶剂和循环次数对催化性能的影响。

1Niche construction can lead to stable coexistence of diverse genotypes in spatially structured population, which supports a stable polymorphism even without heterozygote superiority.(2)With habitat deterioration, niche construction accelerates the formation of steady polymorphism and hence impedes the harmful influences of environment on the population, which might embody a life-history strategy of organism under the unfavorable environment.(3)Niche construction results in the coexistence with alternative polymorphism through genotype-environment feedback and limited gene flow.(4)The niche-constructing organism is an active force to alter its environment and hence the direction of natural selection in order to better survival.(5)Spatial dynamics and distribution pattern of metapopulation are profoundly influenced by time-lagged niche construction.(6)Metapopulation size can reach a fixed level in the recency effect and equal weighting of time lag but is statistical stability in primacy effect, which implies the primacy effect is most remarkable.(7)The increment in the relative weightingof each generation\' niche construction and the length of time lag are significant factors for system destabilization.(8)Moderate capacity of positive niche construction benefits the metapopulation persistence.(9)The narrowing of niche breadth can decrease the metapopulation size and thereby increase the extinction risk.(10)The coupled function of time lag and niche construction make the system oscillation and generate the spiral wave, spiral-broken and circular wave in heterogeneous habitat.The spatial distributions of metapopulation and resource content are complementary due to a phase lag of their both frequencies.(12)Metapopulation persistence with niche construction depends not only on the balance between colonization and extinction, but also on the balance between the ability of niche construction and natural dissipation of habitat.(13)Metapopula-tion can survive under certain condition when the percent of suitable patches in habitat is lower than the ration of extinction to colonization.(14)Two thresholds exist in the process of transition of habitat quality dynamics from unsuitable to suitable, which include the intensity of niche construction and the initial condition of system.(15)Metapopulation size is positive correlated with the ability of positive niche construction, which means that organism or population who has strongly positive influences on their environment plays an important role to maintain the available habitat.

通过上述几个方面的研究，主要得出以下15条结论：(1)生态位构建可使空间结构种群，甚至是在没有杂合子优势的条件下，形成多种可能的稳定基因型分布模式；(2)随着环境的破坏与恶化，种群的生态位构建作用加速其较早形成稳定多态以阻碍环境对种群的不利影响，解释了有机体在不利环境下的一种生活史对策；(3)生态位构建作用通过基因型—环境反馈机制及有限的基因交流导致基因型多态的稳定共存；(4)有机体的生态位构建作用是一种积极的动力改变环境进而改变其自然选择的方向；(5)生态位构建的时滞作用对集合种群动态和空间分布产生深刻影响；(6)集合种群大小在时滞的崭新效应和等权重效应下达到一固定值，而在首位效应下达到统计稳定，表明首位效应的影响最显著；(7)首位效应下生态位构建相对权重的增量和时滞的长度是影响系统不稳定性动态的关键因素；(8)适中的生态位构建强度有利于集合种群的续存；(9)生态位宽度变窄会减少集合种群的数量从而增加其灭绝风险；(10)时滞和生态位构建的双重作用使系统产生周期振荡，并在异质性环境中产生稳定的螺旋波，破碎的螺旋波和环形波三种分布模式；(11)集合种群与资源含量的空间分布因为相滞而互补；(12)具有生态位构建的集合种群续存不仅取决于侵占率与灭绝率之间的平衡，而且依赖于生态位构建能力同其生境的自然消耗速率之间的妥协；(13)当生境中适合侵占的斑块比例小于其侵占率与灭绝率之比时，生态位构建作用促使集合种群在一定条件下续存：(14)生境斑块的状态从不适合到适合转变过程中存在生态位构建强度和系统初始条件这两个阈值；(15)集合种群的大小同正生态位构建能力正相关，意味着对环境具有较强正作用的有机体对维持有效生境起积极作用。

Alcoa recently announced that its Alcoa World Alumina and Chemicals affiliate and the Government of Jamaica have signed an agreement in principle to expand the Jamalco alumina refinery in Clarendon, Jamaica, by more than 1.5 million metric tons per year.

Alcoa公司最近宣布了其分公司－世界氧化铝及化学产品分厂将在牙买加的Clarendon扩充氧化铝产量的决定，该决定是和牙买加政府的合作下完成的，预计扩产后的氧化铝年产量将比原来的产量多出一倍，达到2800万吨/每年。

Results Compared to the traditional barium clyster,clinical digital examination and colonoscopic examination,defecography is more sensitive and accurate to provide the reliable evidences for the clinical treatment.

结果 比传统钡灌肠、临床指诊及结肠镜检查更为敏感和准确，为临床治疗提供了可靠证据。

Methods: The coarctation of the abdominal aorta hypertension model was established in rats.

建立腹主动脉缩窄性高血压大鼠模型，测定平均动脉压和左心室/体重比值；测量大鼠心肌的体积密度、表面积密度、比表面及平均自由程等。

Methods The coarctation of the abdominal aorta hypertension model was established in Sprague-Dawley rats.

建立腹主动脉缩窄性高血压大鼠模型，测定大鼠平均动脉压、大鼠心肌的表面积密度、体积密度、比表面及平均自由程等各项体视学参数并计算。

In the chapter 3, first introduces estimator of functional coefficient autoregressive model and local linear estimation method and its asymptotic normality forα-mixing samples is given and improved selected method of parameters, then studies application of FAR model in stock market, finally compared goodness of fit between AR and FAR models by generalized likelihood ratio method, and then forecast result.

其中，我们对模型参数的选择方法略作改进，使之更具可操作性，然后用函数系数自回归模型对上海股市日收益率进行实证研究，并利用广义似然比检验对函数系数模型和线性模型进行有效性检验及预测结果比较。

In the one half part, according to the strontium nature, thermodynamic calculation of correlative reaction and the principle of the vacuum aluminothermy reduction process, with the laboratory findings of preparation strontium by vacuum aluminothermy reduction compared and analyzed in different parameter conditions, a variety of factors which effect the decomposition rate of SrCO_3 and the percent reduction of strontia are gotten out. The factors include that the decomposition rate of SrCO_3 is influenced by different addition and pressure. They also include that the percent reduction of strontia is influenced by excess coefficient of reducing agent aluminium powder, the particle size of raw material or reducing agent, the pressure of barbecuing, temperature and reduction time. According to those, we can draw the conclusion as follows:(1) Decomposition temperature of SrCO_3 is decreased by adding carbon and alumina in different degree.(2) With quantitative carbon added under the vacuum condition, the decomposition temperature of SrCO_3 is decreased obviously, which can fall 150℃ compared with atmospheric pressure.(3) In keeping 1150℃ of 2.5h, under the 5Pa vacuum condition, the decomposition rate of SrCO_3 nearly keeps in 99% steadily.

在前半部分的真空铝热还原法中，根据锶的性质、相关反应的热力学计算及真空铝热还原法原理，通过对不同参数条件下的真空铝热还原法生产金属锶的实验结果的分析比较，得出了影响SrCO_3的分解率和氧化锶的还原率的种种因素，具体因素包括不同添加剂、不同气压对SrCO_3分解率的影响，还原剂铝粉的过量系数、原料与还原剂的粒度、制团压力、温度和还原时间等对氧化锶还原率的影响，得出具体结论如下：(1)添加碳和Al_2O_3能不同程度的降低SrCO_3的分解温度；(2)真空条件下加入一定量的碳可显著降低SrCO_3的分解温度，比之常压下可降低150℃之多；(3)在1150℃恒温2.5h、真空度达到5Pa的条件下，SrCO_3的分解率几乎保持稳定在99％；(4)氧化锶的还原率随还原剂过量系数的增大而增大，但是趋势越来越小，当过量系数超过25％后，氧化锶的还原率几乎不再增加；(5)氧化锶的还原率随原料与还原剂的粒度的变细而增加；(6)氧化锶的还原率随制团压力的增加而增加，但超过一定值后，氧化锶的还原率反而会下降；(7)氧化锶的还原率随还原温度的升高而增加；(8)氧化锶的还原率随还原时间延长而增加，在本实验条件下，超过2.5h趋于稳定。

The paper calculates the viscosity coefficient of two-phase solution that contains gas and liquid with the statistical mechanics and dynamics method.

采用统计力学模型对气液两相流体的粘滞系数进行了研究。认为这种模型比一般的液体理论方法直观和简洁，能更好地分析和计算两相流的粘度与其温度、流压及含气率的关系。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。