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11.
基因科技发展对生命健康权、隐私权、环境权与发展权等人权保护都已产生正负两面性影响。这种双重影响的原因是多种的：包括基因技术的安全性、研究者的科研自由、基因技术引发的平等主体间的权利冲突、基因技术引发的私人权利和公共利益的冲突。我们需要对基因技术进行法律调整以促进其良性发展。 相似文献
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Zhi-xue Xu Ran Zhang You-xiang Wang Qiao-ling Hu 《Journal of Zhejiang University. Science. B》2010,11(4):292-297
The calcium phosphate (CaP) particles have attracted much attention in gene therapy. How to construct stable gene particles was the determining factor. In this study,hybrid multi-shell CaP gene particles were successfully constructed. First,CaP nanoparticles served as a core and were coated with DNA for colloidal stabilization. The ξ-potential of DNA-coated CaP nanoparticles was -15 mV. Then polyethylenimine (PEI) was added and adsorbed outside of the DNA layer due to the electrostatic attraction. The ξ-pot... 相似文献
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Proliferation of endothelial cell on polytetrafluoroethylene vascular graft materials carried VEGF gene plasmid 总被引：1，自引：0，他引：1
Tao SF Chen L Zheng YX Xu Y Chen J Yu H 《Journal of Zhejiang University. Science. B》2006,7(6):421-428
Objective： To investigate whether vascular endothelial growth factor （VEGF） gene plasmid carried by polytetrafluoroethylene （PTFE） vascular graft materials could transfect endothelial cells （ECs） and promote their growth. Methods： PTFE vascular graft materials carried with pCDI-hVEGF121, pCDI or pEGFP were incubated in Tris-buffer solution and the values of optical density of 260 nm at different time were plotted, then the DNA controlled release curve was made. ECs derived from human umbilical vein were seeded on the pCDI-hVEGF121/pCDI/pEGFP-PTFE materials or tissue culture plates, ECs numbers were counted and VEGF protein concentrations at different time were measured by enzyme-linked immunoadsorbent assay method. Green fluorescent protein （GFP） expression in ECs on pEGFP-PTFE materials was examined with fluorescence mi- croscopy. Results： The controlled release curve showed that the gene released from PTFE materials was rapid within 8 h, then slowed down and that the gene released continuously even after 72 h. At 24, 72 and 120 h, ECs number and proliferation rate of pCDI-hVEGFI21-PTFE materials were higher than those ofpCDI or pEGFP-PTFE materials （P〈0.05）. VEGF protein concentration of pCDI-hVEGF121-PTFE materials was higher than that of pC DI or pEGFP-PTFE materials at 6, 24, 72 and 120 h （P〈0.01）. GFP expression in ECs on the pEGFP-PTFE materials could be detected by fluorescence microscopy. Conclusion： PTFE graft can be used as a carrier of VEGF gene plasmid, VEGF gene carried by PTFE can transfect ECs and promote ECs growth. 相似文献
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本文在人教版新教材《高三生物选修》课本中“生物固氯”的基础上进行分析、拓展和深化，使读者在一定程度上了解生物固氦的概念、过程、意义和前景，从而培养学生正确学习生物学的观念和态度，提高学生理论与实践相结合的能力。 相似文献
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目的:初步调查我国北方地区汉、回、蒙古族健康人群MBL基因ExonⅠ54位密码子点突变的情况,检测其血浆MBL含量,探讨二者的相关性。方法:用PCR-RFLP检测MBL基因点突变频率;用MBLOli-gomerELISA试剂盒测定血浆MBL含量。结果:健康汉族人该基因突变频率0.23,血浆MBL含量均值1.99±1.50mg/L,二者负相关(r=-0.62);回族人突变频率0.15,MBL含量均值3.40±2.55mg/L,二者负相关(r=-0.67);蒙古族人基因突变频率0.18,含量均值2.52±1.95mg/L,二者负相关(r=-0.64)。结论:健康汉、回、蒙古族人MBL基因54位密码子点突变频率与其血浆含量均呈负相关。 相似文献
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目的:在康脑液方剂干预下观察皮质区内源性神经细胞干细胞因子(SCF)mRNA在大鼠脑缺血再灌注损伤后不同时间的表达情况。方法:成年SD大鼠,以线栓法建立大脑中动脉缺血再灌注模型,随机分为模型组、药物干预组和假手术组。原位杂交技术检测脑缺血1.5h再灌注1～14d后,脑皮质区SCFmRNA表达情况。结果:脑缺血再灌注后,药物干预组、模型组SCFmRNA的表达在皮质区均明显高于假手术组,于第7天达高峰,第14天下降。结论:药物干预后脑缺血再灌注脑皮质区SCFmRNA表达在不同时间点与模型组具备相同的表达规律,两组SCFmRNA的表达无显著性差异。 相似文献
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Li Chao Brant Eleanor Budak Hikmet Zhang Baohong 《Journal of Zhejiang University. Science. B》2021,22(4):253-284
Since it was first recognized in bacteria and archaea as a mechanism for innate viral immunity in the early 2010 s,clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas) has rapidly been developed into a robust, multifunctional genome editing tool with many uses. Following the discovery of the initial CRISPR/Cas-based system, the technology has been advanced to facilitate a multitude of different functions. These include development as a base editor, prime editor, epigenetic editor, and CRISPR interference(CRISPRi) and CRISPR activator(CRISPRa) gene regulators. It can also be used for chromatin and RNA targeting and imaging. Its applications have proved revolutionary across numerous biological fields, especially in biomedical and agricultural improvement. As a diagnostic tool, CRISPR has been developed to aid the detection and screening of both human and plant diseases, and has even been applied during the current coronavirus disease 2019(COVID-19) pandemic. CRISPR/Cas is also being trialed as a new form of gene therapy for treating various human diseases, including cancers, and has aided drug development. In terms of agricultural breeding, precise targeting of biological pathways via CRISPR/Cas has been key to regulating molecular biosynthesis and allowing modification of proteins, starch, oil, and other functional components for crop improvement. Adding to this, CRISPR/Cas has been shown capable of significantly enhancing both plant tolerance to environmental stresses and overall crop yield via the targeting of various agronomically important gene regulators. Looking to the future, increasing the efficiency and precision of CRISPR/Cas delivery systems and limiting off-target activity are two major challenges for wider application of the technology. This review provides an in-depth overview of current CRISPR development, including the advantages and disadvantages of the technology,recent applications, and future considerations. 相似文献
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