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101.
人Heparanase基因真核和原核表达载体的构建及融合蛋白的表达 总被引:1,自引:1,他引:0
目的:构建人Heparanase基因的真核、原核表达载体,大肠杆菌表达其融合蛋白.方法:采用反转录.聚合酶链反应从人肝癌细胞株HepG2cDNA中,分别扩增出Heparanase编码基因,用限制性内切酶BamHI消化后,插入真核表达载体pcDNA3.1中,经酶切鉴定与测序证实后,连接成包括完整的人Heparanase基因ORF区的真核表达载体,以亚克隆法构建于原核表达载体pRSET的相应酶切位点,转化大肠杆菌BL21菌株,异丙基β-D硫代半乳糖苷(IPTG)诱导产生融合蛋白.结果:构建的人Heparanase基因表达载体经序列测定证实,与GenBank登录结果完全一致;双酶切鉴定证实,克隆基因正确插入载体pcDNA3.1及pRSET;SDS-PAGE证实融合蛋白表达成功.结论:成功构建了人Heparanase基因真核、原核表达载体,成功正确表达了6His/Heparanase融合蛋白 相似文献
102.
精子质量参数分析的标准化与质量控制的研究进展 总被引:4,自引:4,他引:0
精液分析是评价男性生育能力的最基本测试。最近几年,对精液分析标准化的迫切需求已引起男科学家的广泛重视。本文对精子质量参数———精子密度、活动率和形态学分析的标准化及质量控制进行了综述。精子密度分析的关键是计数池的标准化,因此Cell-VU计数池应该是最佳的选择;精子活动率和精子形态学的分析由于主观性太强,CASA系统可能是其标准化的最终选择。精液质量参数分析的质量控制主要是质量控制材料的选择,以及在男科学实验室实施EQC和IQC项目,而一些监测质量控制的图表和计算方法应被相应地建立。 相似文献
103.
104.
浙江省温州市2004年结核病监测结果分析 总被引:3,自引:0,他引:3
目的 通过分析温州市2004年结核病监测资料评价现行的防治措施效果.方法 收集并分析温州市2004年结核病监测报表.结果监测点涂阳新登记率为27.45/10万,其中流动人口为26.84/10万,流动人口病例涂阳比例(68.3%)明显高于总人口病例涂阳比例(45.9%),新登涂阳病例1年转归队列分析治愈率为86.6%.结论 提高涂阳病人的发现率依然是本地区结核病控制工作的重点,流动人口结核病问题不容忽视. 相似文献
105.
L. Kalinauskiene D. Cekuoliene M. H. Van IJzendoorn † M. J. Bakermans-Kranenburg † F. Juffer† I. Kusakovskaja 《Child: care, health and development》2009,35(5):613-623
Objective This randomized control trial examined the effects of a short-term, interaction-focused and attachment-based video-feedback intervention (VIPP: video-feedback intervention to promote positive parenting).
Design VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants. 相似文献
Design VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants. 相似文献
106.
Motor imagery (MI), which refers to the process of mental representation of movements, has not been studied in patients with essential tremor (ET). We investigated the presence of impaired MI in ET patients compared with healthy controls. A group of drug-naive and nondemented ET patients and age-matched controls were studied using transcranial magnetic stimulation, while they were specifically instructed to try and imagine themselves performing two motor tasks. The various clinical and electrophysiological variables were evaluated and compared. Repeated measures ANOVA demonstrated a significant difference between ET patients and controls with respect to mean motor-evoked potential (MEP) amplitudes (F(1,38) = 31.92, P < 0.005) during MI. The process of MI effectively facilitated MEP amplitude in controls but not in ET patients, regardless of side of stimulation or motor tasks. We provide evidence to demonstrate impairment of MI in a group of ET patients compared with healthy controls. The basis for this novel finding is unclear, and further studies are warranted to determine whether it is related to cerebellar or motor cortical dysfunction. 相似文献
107.
The ripple-free deadbeat control problem for SISO plants subjected to arbitrary reference signals is considered. The trade-off between the settling time and the integral square error between the system output and reference signal is investigated. Given a specific order of the controller, it is shown how to design an optimal ripple-free deadbeat controller. An illustrative example is presented to show the feasibility of the proposed algorithm. 相似文献
108.
对全国部分城乡家鼠鼠情监测三年结果的分析表明:城乡家鼠组成均以三大家鼠(褐家鼠、小家鼠、黄胸鼠)为主,其次为食虫目臭鼩鼱~#和黑线姬鼠。五种主要鼠种在家鼠组成中的数量比基本稳定,但三年中城乡少数鼠种间的顺位有所变化。监测结果亦表明,五种主要鼠种的地区分布是:褐家鼠、小家鼠遍布所有监测的省、市、区,同以往文献中遍布全国的说法一致;黄胸鼠分布于黄河以南;食虫目中的臭鼩鼱分布于华中区以南的广大地区。这在以往文献中均已有记载,但以往文献有关黄胸鼠和臭鼩鼱分布的其他说法,则被证实为不确切的。黑线姬鼠的分布范围已超过以往文献中关于分布于东北、华北及长江流域的说法,但以往文献中关于该鼠种遍及全国的说法是否正确,则有待进一步证实。 相似文献
109.
A. G. Sreenatha M. Seetharama Bhat S. K. Shrivastava 《Optimal control applications & methods.》1990,11(1):51-66
The design of a low-order dynamic output feedback controller for a flexible spacecraft is carried out using modified linear quadratic Gaussian (LQG) theory. The necessary conditions for optimization are given. The linear equations governing a flexible spacecraft with a central rigid body and two sun-tracking solar panels are presented. The parameters of the Solar Electric Propulsion Spacecraft (SEPS) are selected for analysis and simulation. The optimal gains for the dynamic controller are estimated using an iterative algorithm. The sequential procedure which assures convergence is selected. The initial gains which stabilize the system are chosen on the basis of the principle of a PD controller. A third-order controller for pitch, roll and yaw axes of the 18th-order system, which includes sensor and actuator dynamics, is designed. Numerical simulations carried out to ascertain the performance of the controller show the performance to be satisfactory. 相似文献
110.
In order to evaluate the pump output control based on the oxygen delivery to peripheral tissues, arterial and mixed venous hemoglobin content ([Hb]) and oxygen saturation (SO2) were continuously monitored in three biventricular bypass animals (3-, 6-, and 40-day experiments) with fibrillating ventricles. The specially developed oxygen sensors were mounted in the outflow ports of the artificial hearts to measure [Hb] and SO2. One animal was exercised on the treadmill at 2.0 mile/h for 15 min with pump flows fixed to deliver oxygen of (a) above 13 cc/min/kg, (b) 10, and (c) 9. In (a), the mixed venous saturation (SvO2) dropped to approximately 25% with no increase in the blood lactate level. In (b) and (c), the SvO2 decreased to approximately 10-15% with increase in blood lactate levels from 4 to 10-30 mg/dl. Also, the recovery of the SvO2 in these groups following the termination of the exercise was slower in comparison to (a). The lower limit of the SvO2 level that would create oxygen debt situation in the peripheral tissues was approximately 25-30% for the exercise of 2.0 mile/h. The SvO2 reflects changes in respiratory status, pump output, hemoglobin level, and metabolism, and is thus a useful indicator to diagnose quickly the circulatory status as well as possibly to control the artificial heart output. 相似文献