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991.
网络环境下教育学院图书馆应以其在本地区教育系统的特殊地位,联合中学图书馆建立图书馆联合体,开展资源共享。在分析了联合体的地位和作用的基础上,指出了联合体在其建设过程中必须坚持的原则和应具备的特点。 相似文献
992.
Yangxueqingnao particles inhibit rat vascular smooth muscle cell proliferation induced by lysophosphatidic acid 总被引:1,自引:0,他引:1
Cai W Xu Y Chen JZ Huang SR Lu ZY Wang ZK 《Journal of Zhejiang University. Science. B》2005,6(9):892-896
Objective: To observe the effect of Yangxueqingnao particles on rat vascular smooth muscle cell (VSMC) proliferation induced by lysophosphatidic acid (LPA). Methods: The amount of3H-TdR (3H-thymidine) admixed in cultured rat VSMC was measured and mitogen-activated protein kinase (MAPK) activity and lipid peroxidation end product malondialdehyde (MDA)content of the VSMC were assayed. Results: 1×10-9, 1×10-8, 1×10-7 mol/L LPA in a concentration dependent manner, induced the amount of 3H-TdR admixed, MAP kinase activity, and MDA content of the cultured rat VSMC to increase. However, 5%, 10%,and 15% Yangxueqingnao serum preincubation resulted in a decrease of 23.0%, 42.0%, and 52.0% (P<0.01) respectively in the amount of 3H-TdR admixed, a decline in VSMC MAP kinase activity of 13.9% (P<0.05), 29.6% (P<0.01), and 48.9% (P<0.01)respectively, and also, a decrease in MDA content of VSMC of 19.4%, 24.7%, and 43.2% (P<0.01) respectively, in the 1×10-7mol/L LPA-treated VSMC. Conclusions: LPA activates the proliferation and lipid peroxidation of VSMC in a concentration dependent manner. The LPA-induced VSMC proliferation is related to the activity of MAP kinases, enzymes involved in an intracellular signalling pathway. The results of the present study showed that Yangxueqingnao particles can effectively inhibit LPA-induced VSMC proliferation, MAP kinase activation, and reduce lipid peroxidative lesion. 相似文献
993.
周红 《湖南城市学院学报》2002,23(5):76-79
湖南广电的超常规发展引发了"湖南电视现象",主要是由于能动的观念、人才的张力和文化的底蕴等因素的作用;当前应进一步攻破难点,乘势打造扩张型媒介航母. 相似文献
994.
加入WTO后,对我国农业既有下面影响,同时也存在着负面影响,我们要做好充分准备,调整农业产业结构,采取各项措施,不失时机地发展我国农业。 相似文献
995.
通过Piers-Harris儿童自我概念量表筛选出三至五年级低自我概念的学生,实验组接受认知训练,控制组不接受训练。认知训练以后,三个年级的实验组的自我概念水平提高的幅度均比控制组的幅度要大,经统计检验,差异都非常显著。这表明:(1)认知训练可提高学生的自我概念水平;(2)小学三到五年级自我概念水平的训练效果不存在年龄差异;(3)小学三到五年级自我概念的训练效果不存在性别差异。 相似文献
996.
Indigenous cultural contexts for STEM experiences: snow snakes’ impact on students and the community
Opportunities for American Indian youth to meaningfully engage in school-based science, technology, engineering, and mathematics (STEM) experiences have historically been inadequate. As a consequence, American Indian students perform lower on standardized assessments of science education than their peers. In this article we describe the emergence of meaning for students—as well as their community—resulting from Indigenous culturally-based STEM curriculum that used an American Indian tradition as a focal context. Specifically, the game of snow snakes (Gooneginebig in Ojibwe) afforded an opportunity for STEM and culturally-based resources to work in unison. A case study research design was used with the bounded case represented by the community associated with the snow snake project. The research question guiding this study was: What forms of culturally relevant meaning do students and the community form as a result of the snow snake game? Results indicate evidence of increased student and community engagement through culturally-based STEM experiences in the form of active participation and the rejuvenation of a traditional game. Implications are discussed for using culturally-based contexts for STEM learning. 相似文献
997.
Objective: To construct a PC12 cell strain with neuronal differentiation, and observe the apoptosis and pro-liferation activity effects induced these cells by Amyloid beta-Protein (Aβ-43). Methods: 1) PC12 cells in logarithmicgrowth phase were subcultured for 24 h. After the culture fluid was changed, the cells were treated with Rat-β-NGF andcultured for 9 days. 2) Neuronal differentiation of PC12 cells in logarithmic growth phase were divided into four groups:control group (0), experimental group (1), experimental group (2) and experimental group (3). The concentrations of Aβ inthe four groups were 0 μmol/L, 1.25 μ mol/L, 2.5 μ mol/L and 5 μmol/L, respectively. The cells were harvested at 24, 48 and72 h later and stained with AnnexinV-FITC/PI after centrifugation and washing. Then flow cytometry was conducted toexamine the apoptosis percentage. 3) NGF-induced PC12 cells were selected and Aβ with different concentrations wasadded. The final concentrations of Aβ were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μ mol/L, respectively. After the cellswere incubated in an atmosphere of 5% CO2 at 37 ℃ in an incubator for 72 h, the OD values were examined. Results: 1)Neuronal differentiated PC 12 cell lines were successfully established. 2) Flow cytometric examination indicated that Aβ(1.25, 2.5, and 5.0 μmol/L) could effectively induce apoptosis of neuronal-differented cells at the 24 h, 48 h and 72 h timepoints. 3) Aβ (0-5.00 μ mol/L) had no obvious effect on proliferation or restraining of the neuronal differentiation of thePC 12 cells after a 72 h interacting process. Conclusion: This investigation revealed successful neuronal differentiation of thePC12 cell strain. The induction of apoptosis of the neurocytes by various concentrations of Aβ was observed and the in-fluence of Aβ on induced proliferation of PC 12 cells by Rat-β-NGF was revealed. This study -05 provide basis for futureresearch on the molecular cure of AD and interdiction of AD evolution. 相似文献
998.
在中学教育中,由于家庭环境、学校环境、社会环境的影响,加上学生自身因素及教师的教育观念教育方法滞后、道德意识淡薄、专业修养不足,导致师生问的信任度低。要提高教师在学生心中的信任度,应注意提高认识,尊重信任学生,增强信任投入、信任平衡和教师与学生的信任互换。 相似文献
999.
The introduced study represents methodology and results of research focused on utilization of interactive whiteboard as didactic technology mediating information through multimedia worksheets applied in education process in pre-primary education. Its aim was to determine whether it can significantly increase the level of children’s acquired knowledge in the field of technical skills education and whether it can positively influence the development of children’s creative skills as a sign of their motivation. We observe that this issue in the way it is theoretically and practically established in this study can contribute by proposing education standards and set of multimedia worksheets in the technical field in Slovak pre-primary education. 相似文献
1000.
Zi-yi Zhu Xu Yong Rao-jun Luo Yun-zhen Wang 《Journal of Zhejiang University. Science. B》2018,19(9):718-725
Objective: McKeown esophagectomy followed by cervical and abdominal procedures has been commonly used for invasive esophageal carcinoma. This minimally-invasive operative procedure in the lateral prone position has been considered to be the most appropriate method. We describe our experiences in minimally invasive McKeown esophagectomy (MIME) for esophageal cancer. Methods: Between March 2016 and February 2018, a total of 82 patients underwent MIME by a single group in our department (a single center). All procedure, operation, oncology, and complication data were reviewed. Results: All MIME procedures were completed successfully, with no conversions to open surgery. The median operative time was 260 min, and median blood loss was 100 ml. The average number of total harvested lymph nodes was 20.1 in the chest and 13.5 in the abdomen. There were no deaths within 30 postoperative days. Twenty cases (24.4%) developed postoperative complications, including anastomotic leak in 4 (4.9%), single lateral recurrent nerve palsy in 4 (4.9%), bilateral recurrent nerve palsy in 1 (1.2%), pulmonary problems in 3 (3.7%), chyle leak in 1 (1.2%), and other complications in 7 (including pleural effusions in 4, incomplete ileus in 2, and neck incision infection in 1; 8.54%). Average postoperative hospitalization time was 12 d. Blood loss, operation time, morbidity rate, and the number of harvested lymph nodes were analyzed by evaluating learning curves in different periods. Significant differences were found in operative time (P=0.006), postoperative hospitalization days (P=0.015), total harvested lymph nodes (P=0.003), harvested thoracic lymph nodes (P=0.006), and harvested abdominal lymph nodes (P=0.022) among different periods. Conclusions: Surgical outcomes following MIME for esophageal cancer are safe and acceptable. The MIME procedure for stages I and II could be performed proficiently and reached an experience plateau after approximately 25 cases. 相似文献