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排序方式: 共有209条查询结果,搜索用时 15 毫秒
11.
Chai-Hong Yeong Mu-hua Cheng Kwan-Hoong Ng 《Journal of Zhejiang University. Science. B》2014,15(10):845-863
The potential use of radionuclides in therapy has been recognized for many decades. A number of radionuclides, such as iodine-131 (131I), phosphorous-32 (32P), strontium-90 (90Sr), and yttrium-90 (90Y), have been used successfully for the treatment of many benign and malignant disorders. Recently, the rapid growth of this branch of nuclear medicine has been stimulated by the introduction of a number of new radionuclides and radiopharmaceuticals for the treatment of metastatic bone pain and neuroendocrine and other malignant or non-malignant tumours. Today, the field of radionuclide therapy is enjoying an exciting phase and is poised for greater growth and development in the coming years. For example, in Asia, the high prevalence of thyroid and liver diseases has prompted many novel developments and clinical trials using targeted radionuclide therapy. This paper reviews the characteristics and clinical applications of the commonly available therapeutic radionuclides, as well as the problems and issues involved in translating novel radionuclides into clinical therapies. 相似文献
12.
Jiang SHI Li WANG Cheng-ying MA Hai-peng LV Zong-mao CHEN Zhi LIN 《Journal of Zhejiang University. Science. B》2014,15(4):313-321
研究目的:为茉莉酸甲酯诱导来提高茶叶香气品质提供理论依据,为新型花香红茶的研制提供技术支持。创新要点:首次将茉莉酸甲酯应用于诱导茶叶香气品质提高,初步验证了茶叶香气品质提高的本质原因:相关酶活性提高,基因表达上调。研究方法:采用顶空固相微萃取法(HS-SPME)对红茶香气进行富集,气相色谱-质谱联用仪(GC-MS)进行解吸附分析,实时定量多聚酶链式反应(qRT-PCR)分析茶鲜叶中香气相关酶基因表达。重要结论:茉莉酸甲酯诱导后的茶鲜叶中多酚氧化酶(PPO)活性上升,β-葡萄糖苷酶活性下降;PPO和β-樱草糖苷酶基因表达上调,β-葡萄糖苷酶基因表达下调。茉莉酸甲酯诱导后的茶鲜叶能明显提高由其制成的红茶香气品质,且萜烯醇类和萜烯类含量明显提高。 相似文献
13.
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
14.
15.
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
16.
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
17.
恶性肿瘤(癌症)是尚未被攻克的重大疾病之一,主要原因之一是临床上抗肿瘤药物效用不大.具有抗肿瘤活性的阳离子肽(CAP)主要结合肿瘤细胞膜并破坏膜结构,这是通过肽的正电荷与肿瘤细胞膜的负电荷之静电吸引来实现的.与传统化疗药物相比,绕过肿瘤细胞的耐药机制是CAP最突出的优势.本文对抗肿瘤肽的主要结构特征、抗肿瘤效果和抗肿瘤机制(以鲎素为例)进行了综述.作者认为,寻找靶向肿瘤干细胞的CAP对于治愈肿瘤具有特别重要的意义.另外,通过化学改构和新剂型研制,CAP将具有高靶向性和低毒性,给抗肿瘤药物开发提供新的动力. 相似文献
18.
The clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 (Cas9) genome editing system is a powerful tool for targeted gene modifications in a wide range of species, including plants. Over the last few years, this system has revolutionized the way scientists perform genetic studies and crop breeding, due to its simplicity, flexibility, consistency and high efficiency. Considerable progress has been made in optimizing CRISPR/Cas9 systems in plants, particularly for targeted gene mutagenesis. However, there are still a number of important challenges ahead, including methods for the efficient delivery of CRISPR and other editing tools to most plants, and more effective strategies for sequence knock-ins and replacements. We provide our viewpoint on the goals, potential concerns and future challenges for the development and application of plant genome editing tools. 相似文献
19.
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
20.
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