被子植物精细胞分离和特性研究进展     

朱维红  张妍  崔彬彬 《保定学院学报》2020,(3):114-121

精细胞分离是研究雄性生殖发育的前提之一,近半个世纪以来,人们运用不断更新的生物实验技术,对被子植物精细胞开展了分离及细胞分子特征的研究。分析被子植物精细胞分离方法,总结精细胞二型性与倾向性、细胞融合方面的研究成果,并对其研究意义和前景进行讨论。  相似文献   

视交叉与蝶鞍关系的临床解剖学研究     

张国徽  董建峰  齐效勇 《河北北方学院学报(医学版)》2005,22(2):5-6

目的:研究视交叉的解剖特点,进而为垂体肿瘤切除手术提供解剖学依据.方法:在20例成年男性头部标本上,对视交叉进行观察与测量.结果:视交叉前缘与鞍结节相距4.42±1.17mm,视交叉前缘与交叉前沟相距7.0±1.1mm,视交叉与镰状韧带颅前窝附着处后缘相距10.7±1.02mm,视交叉宽度为10.6±1.2mm,在出视神经管、入颅处,两侧视神经内缘相距14.8±1.9mm.结论:视交叉的解剖关系是垂体瘤手术成功与否的关键.  相似文献   

In vitro study on ribozyme against hepatitis C virus     

Chen Zhi  Liu Yong  Liu Ke-zhou  R. H. Dennin  Dou Jun  U Reinhard 《浙江大学学报(A卷英文版)》2001,2(1):100-103

Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region, were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%, respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion: Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better effect when used together.  相似文献   

水稻胚乳细胞发育与结实特性     

黄升谋 《襄樊学院学报》2011,32(8):24-27

文章对水稻胚乳细胞发育过程、淀粉体和蛋白体结构特征与结实特性、养分输入胚乳细胞的途径、ATPase活性分布与水稻充实的关系、水稻强弱势粒胚乳细胞发育与其结实特性进行分析.提出进一步研究胚乳细胞发育及其超微结构与籽粒生理活性的关系,可从深入开展亚显微水平下强弱势粒背部维管束结构、ATPase的活性分布、差异表达基因对结实特性的影响等方面展开研究.  相似文献   

Mapping the knowledge structure exhibited by a cohort of students based on their understanding of how a galvanic cell produces energy          下载免费PDF全文

Adrian Sin Loy Loh  R. Subramaniam 《科学教学研究杂志》2018,55(6):777-809

This study evaluates the use of an open‐ended question to determine students' knowledge structure on the topic of galvanic cells. The open‐ended question was developed and administered to 163 Grade 10 students who had earlier completed a course on electrochemistry. Students' responses were marked as well as coded on the basis of the fields identified from their responses. This was then evaluated statistically to determine the collective knowledge structure of the sample of students. The knowledge structure thus mapped contains both canonical concepts and alternative conceptions (ACs). An important finding emerging from this study is that instructors need to focus student's attention on the dynamic processes involving electrons and ions during the operation of galvanic cells. In order for students to fully understand how a galvanic cell operates, they need to see the whole picture. There are three critical components that lead to students' understanding of how an oxidation–reduction reaction can generate energy and how a circuit is complete: transfer of electrons during oxidation–reduction half‐reactions, flow of electrons within metals, and migration of ions in solution. Also, we found that it is possible for students to use correct chemistry concepts in an incorrect way by establishing linkages among these in an inappropriate manner. We reiterate that apart from evaluating students' ACs, it is also important to evaluate the links between the concepts and conceptions present in students' knowledge structure so that teaching can be made more effective.  相似文献   

Allograftic bone marrow-derived mesenchymal stem cells transplanted into heart infarcted model of rabbit to renovate infarcted heart     

王建安  李长岭  樊友启  何红  孙勇 《浙江大学学报(A卷英文版)》2004,5(10):1279-1285

Objective: To investigate the directed transplantation of allograftic bone marrow-derived mesenchymal stem cells (MSCs) in myocardial infarcted (MI) model rabbits. Materials and Methods: Rabbits were divided into 3 groups, heart infarcted model with MSCs transplanted treatment (MSCs group, n=12), heart infarcted model with PBS injection (control group, n=20), sham operation with PBS injection (sham group, n=l 7). MSCs labelled by BrdUrd were injected into the MI area of the MSCs group. The same volume of PBS was injected into the MI area of the control group and sham group. The mortality, LVIDd, LVIDs and LVEF Of the two groups were compared 4 weeks later. Tropomyosin inhibitory component (Tn I) and BrdUrd immunohistochemistry identified the engrafted cells 4 weeks after transplantation. Result: The mortality of the MSCs group was 16.7% (2/12), and remarkably lower than the control group's mortality [35% (7/20) (P＜0.05)].Among the animals that survived for 4 weeks, the LVIDd and LVIDs of the MSCs group after operation were 1.17±0.21 cm and 0.74±0.13 cm, and remarkably lower than those of the model group, which were 1.64±0.14 cm and 1.19±0.12 cm (P＜0.05); the LVEF of the MSCs group after operation was 63±6%, and remarkably higher than that of the model group,which was 53±6% (P＜0.05). Among the 10 cases of animals that survived for 4 weeks in the MSCs group, in 8 cases (80%),the transplanted cells survived in the non MI, MI region and its periphery, and even farther away; part of them differentiated into cardiomyocytes; in 7 cases (70%), the transplanted cells participated in the formation of blood vessel tissue in the MI region. Conclusion: Transplanted allograftic MSCs can survive and differentiate into cardiomyocytes, form the blood vessels in the MI region. MSCs transplantation could improve the heart function after MI.  相似文献   

Relationship between the size of pontocerebellar angle tumor and audiology     

Tang Jian-guo  Cai Yi 《浙江大学学报(A卷英文版)》2001,2(1):111-113

Objective: To study the relationship between the size of pontocerebellar angle tumor and audiology. Methods: Retrospective analysis of accoustically evoked brainstem response (ABR) waveforms and pure tone threshold in 27 subjects with tumor of pontocerebellar angle. Results: ABR wave forms and pure tone threshold were significantly affected statistically by the size of tumors, especially those tumor larger than 3 cm in diameter. Conclusion: The primary symptom of the patient was unilateral hearing loss. Early discovery of the lesion is important and ABR is a sensitive tool for early diagnose of the tumor.  相似文献   

以就业为导向加强专业建设的实践探索   总被引：1，自引：0，他引：1  

赵文军  王志勇  尚慧文 《职业技术教育》2005,26(35):81-82

邯郸职业技术学院在以就业为导向、加强专业建设的探索中,以"索求第一、适时调向、主干辐射、以点带面"作为专业建设原则;以就业、创业为目标,积极与企业合作办学;以能力培养为主线,不断优化课程结构,完善专业建设.通过20多年的办学实践,在培养高素质技术技能型人才方面取得了良好的成绩.  相似文献   

Effects of RNA interference-induced tryptase down-regulation in P815 cells on IL-6 and TNF-alpha release of endothelial cells     

Jiang YF  Zhao FD  Li XB  Ning YX  Zhi XL  Qian RZ  Yin LH 《Journal of Zhejiang University. Science. B》2008,9(8):656-661

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雄黄抗MFC小鼠肿瘤的实验研究     

周复辉  付小一 《宜春学院学报》2006,28(6):83-83,94

目的:探讨雄黄对小鼠胃癌细胞株M FC的抑制作用.方法:采用小鼠腋下接种肿瘤细胞悬液,再给予剂量为6.5mg/10g的雄黄液灌胃,观察肿瘤生长变化.结果:雄黄对MFC的抑瘤率为65.4%.结论:雄黄对MFC的生长具有明显的抑制作用.  相似文献