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宋金 《黔东南民族职业技术学院学报》2009,(2)
就天柱县江东乡每年家庭所用薪材的消耗量,进行社会调查,采取定性分析,提出建设生态文明试验区应从三个方面着手:普及家用电器、加大沼气池建设力度,提倡生饲料养猪。 相似文献
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INTRODUCTION Diabetes is the largest morbidity of patients with heart failure and adversely affects outcomes of car- diovascular diseases (Beller, 2001). Oxidative stress has been associated with the pathogenesis of chronic diabetic complications including cardiomyopathy (Cai and Kang, 2003). The ability of antioxidants to inhibit these injuries has raised the possibility of newer therapeutic treatment for diabetic heart dis- eases. Recently, Bcl-2 gene has been focused because it was in… 相似文献
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王挥春(1929年9月19日),笔名涛石,别号翔云斋主,柏树庄人。北京画院专业画家,一级美术师;中国美术家协会会员;中国延安文艺学会理事;中国画研究会研究员兼常务理事;中国名人专家协会常务理事;北京湖社画会会长;齐白石艺术研究会常务理事;北京国际艺术博览会评审委员会副主任;中国书画函授大学教授,艺术大师刘海粟关门弟子。擅长中国写意花鸟山水,曾创作了大型珐琅壁画“鹤乡春晓”。国画“九洲神鹰图”、“留得莲实飨后人”、“雄凤图”、“群鹭祥和图”被天安门管理委员会、毛主席纪念堂、中央档案馆、北京市市政府会议中心等收藏。“秋塘… 相似文献
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研究目的：四轮独立驱动汽车四个车轮的电机转矩可以正、反向输出,有必要对其底盘集成控制系统进行针对性设计以保证各车轮间的协调运作。集成控制系统一般可以分为上层运动控制器和下层力分配器。对于运动控制器的设计,同类研究一般采用滑模控制方法来处理汽车运动的非线性特征,其中终端滑模控制因具有高的稳态精度和有限时间收敛的特点而成为研究热点。对于力分配器的设计,通常方法不能在保证运算效率的同时考虑到执行器的约束,从而很难应用于实际。本文采用终端滑模控制方法来设计运动控制器,通过分析驾驶员操作行为从而更好地追踪理想的车辆运动目标;并提出一种简单有效的转矩分配控制策略,通过考虑轮胎附着极限从而将运动总力分配至四个车轮上。创新要点：本文创新性地将终端滑模控制应用到底盘集成控制系统以实现车辆纵向、侧向及横摆运动的联合控制;本文提出了一种新颖的转矩分配控制策略,将复杂的有约束控制分配问题分解至若干个简单的无约束分配子问题。研究方法：本文采用分层式协调控制方案（图1）,应用非奇异和全局快速终端滑模控制方法设计运动控制器,提出一种基于伪逆矩阵的有约束转矩分配策略,应用驾驶员最优预瞄加速度模型来描述和分析人-车闭环系统的运动响应,通过MATLAB/Simulink和CarSim的联合仿真对所设计的四轮独立驱动汽车转矩分配方法进行对比验证。所设定的三个仿真工况包括：开环方向盘角阶跃输入（图6、7及表2）、闭环双移线工况（图8–10）和闭环对开路面制动（图11–15）,分别用以测试车辆横摆、侧向及纵向方向上的动力学响应。重要结论：本文提出的基于终端滑模控制的四轮独立驱动汽车转矩分配方法将车辆的稳态转向特性由不足转向转变为中性转向,驾驶员从而? 相似文献
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Ex vivo expansion and pluripotential differentiation of cryopreserved human bone marrow mesenchymal stem cells 总被引：3，自引：0，他引：3
Xiang Y Zheng Q Jia BB Huang GP Xu YL Wang JF Pan ZJ 《Journal of Zhejiang University. Science. B》2007,8(2):136-146
This study is aimed at investigating the potentials of ex vivo expansion and pluri-differentiation of cryopreservation of adult human bone marrow mesenchymal stem cells （hMSCs） into chondrocytes, adipocytes and neurocytes. Cryopreserved hMSCs were resuscitated and cultured for 15 passages, and then induced into chondrocytes, adipocytes and neurocytes with corresponding induction medium. The induced cells were observed for morphological properties and detected for expressions of type II collagen, triglyceride or neuron-specific enolase and nestin. The result showed that the resuscitated cells could differentiate into chondrocytes after exposure to transforming growth factor 61 （TGF-~0, insulin-like growth factor I （IGF-I） and vitamin C （Vc）, and uniformly changed morphologically from a spindle-like fibroblastic appearance to a polygonal shape in three weeks. The induced cells were heterochromatic to safranin O and expressed cartilage matrix-procollagenal （If） mRNA. The resuscitated cells cultured in induction medium consisting of dexamethasone, 3-isobutyl-l-methylxanthine, indomethacin and IGF-I showed adipogenesis, and lipid vacuoles accumulation was detectable after 21 d. The resuscitated hMSCs were also induced into neurocytes and expressed nestin and neuron specific endolase （NSE） that were special surface markers associated with neural cells at different stage. This study suggested that the resuscitated hMSCs should be still a population ofpluripotential cells and that it could be used for establishing an abundant bMSC reservoir for further experiment and treatment of various clinical discases. 相似文献
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This survey was designed to clarify the current understanding and clinical management of intra-abdominal hypertension (IAH)/abdominal
compartment syndrome (ACS) among intensive care physicians in tertiary Chinese hospitals. A postal twenty-question questionnaire
was sent to 141 physicians in different intensive care units (ICUs). A total of 108 (76.6%) questionnaires were returned.
Among these, three quarters worked in combined medical-surgical ICUs and nearly 80% had primary training in internal or emergency
medicine. Average ICU beds, annual admission, ICU length of stay, acute physiology and chronic health evaluation (APACHE)
II score, and mortality were 18.2 beds, 764.5 cases, 8.3 d, 19.4, and 21.1%, respectively. Of the respondents, 30.6% never
measured intra-abdominal pressure (IAP). Although the vast majority of the ICUs adopted the exclusively transvesicular method,
the overwhelming majority (88.0%) only measured IAP when there was a clinical suspicion of IAH/ACS and only 29.3% measured
either often or routinely. Moreover, 84.0% used the wrong priming saline volume while 88.0% zeroed at reference points which
were not in consistence with the standard method for IAP monitoring recommended by the World Society of Abdominal Compartment
Syndrome. ACS was suspected mainly when there was a distended abdomen (92%), worsening oliguria (80%), and increased ventilatory
support requirement (68%). Common causes for IAH/ACS were “third-spacing from massive volume resuscitation in different settings”
(88%), “intra-abdominal bleeding”, and “liver failure with ascites” (52% for both). Though 60% respondents would recommend
surgical decompression when the IAP exceeded 25 mmHg, accompanied by signs of organ dysfunction, nearly three quarters of
respondents preferred diuresis and dialysis. A total of 68% of respondents would recommend paracentesis in the treatment for
ACS. In conclusion, urgent systematic education is absolutely necessary for most intensive care physicians in China to help
to establish clear diagnostic criteria and appropriate management for these common, but life-threatening, diseases. 相似文献
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Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧrelated antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma. 相似文献