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151.
Cystic hydatid disease in humans is caused by the zoonotic parasite Echinococcus granulosus. As an aid to control transmission of the parasite, a vaccine has been produced for prevention of infection in the parasite’s natural animal intermediate hosts. The vaccine utilizes the recombinant oncosphere protein, EG95. An investigation into the genetic variability of EG95 was undertaken in this study to assess potential antigenic variability in E. granulosus with respect to this host-protective protein. Gene-specific PCR conditions were first established to preferentially amplify the EG95 vaccine-encoding gene (designated eg95-1) from the E. granulosus genome that also contains several other EG95-related genes. The optimized PCR conditions were used to amplify eg95-1 from several parasite isolates in order to determine the protein-coding sequence of the gene. An identical eg95-1 gene was amplified from parasites showing a G1 or G2 genotype of E. granulosus. However, from isolates having a G6 or G7 genotype, a gene was amplified which had substantial nucleotide substitutions (encoding amino acid substitutions) compared with the eg95 gene family members. The amino acid substitutions of EG95 in the G6/G7 genotypes may affect the antigenicity/efficacy of the EG95 recombinant antigen against parasites of these genotypes. These findings indicate that characterization of eg95 gene family members in other strains/isolates of E. granulosus may provide valuable information about the potential for the EG95 hydatid vaccine to be effective against E. granulosus strains other than the G1 genotype.  相似文献   
152.
目的:了解人胃窦粘膜内胃泌素和生长抑素及其mRNA在细胞内的表达和定位。方法:用免疫细胞化学和原位杂交技术。结果:G细胞内的胃泌素主要位于细胞的基部和侧部,而其mRNA则位于核周和核上区;D细胞内的生长抑素不仅位于细胞的基部,也见于细胞突起,其mRNA则位于核周、核上区以及突起。G、D细胞均有开放型和闭合型。结论:G细胞为内分泌方式,而D细胞在人胃窦部可能存在两种细胞亚群,除旁分泌外,也有内分泌方式。  相似文献   
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报道逆转录-多聚酶链式反应(RT-PCR)联合一步程序,扩增大于1kb的拟南芥菜G蛋白α亚基基因的开放阅读框,该程序中,当RNA模板和引物变性,并在同一管中加入PCR缓冲液,4种dNTP底物,逆转录酶和TaqDNA聚合酶之后,就不需其它手工操作步骤,因而可同时进行大批量样品的操作,实验结果证明AMV(鸟类骨髓性白血病病毒)逆转录酶对TaqDNA聚合酶的活性没有抑制作用,这种RT-PCR联合一步法可  相似文献   
154.
Antisense DNA target sites can be selected by the accessibility of the mRNA target. It remains unknown whether a mRNA site that is accessible to an antisense DNA is also a good candidate target site for a siRNA. Here, we reported a parallel analysis of 12 pairs of antisense DNAs and siRNA duplexes for their potency to inhibit reporter luciferase activity in mammalian cells, both of the antisense DNA and siRNA agents in a pair being directed to same site in the mRNA. Five siRNAs and two antisense DNAs turned out to be effective, but the sites targeted by those effective siRNAs and antisense DNAs did not overlap. Our results indicated that effective antisense DNAs and siRNAs have different preferences for target sites in the mRNA.  相似文献   
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A novel approach for the synthesis of 5′-capped 2′-O-methyloligoribonucleotides on a disulfide-tethered solid support is described. The key step of the synthesis is ZnCl2 promoted coupling of m7GDP imidazolide to a fully deprotected oligonucleotide 5′-phosphate on-support. By this methodology m7G5′pppm2′Apm2′Upm2′Ap has been prepared.  相似文献   
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Objective

To determine the effect of laser needle-knife on PI-3K, AKT and VEGF mRNA expression of vertebral arteries in a rabbit model of cervical spondylotic arteriopathy (CSA) and the mechanism of action involved.

Methods

Forty healthy general-grade rabbits were divided into a normal control group, model group, acupuncture group, and laser needle-knife group (n?=?10 rabbits per group), and the CSA rabbit model was established in all but groups but the normal control group. CSA model rabbits in the acupuncture group were treated by acupuncture at the Fengchi (GB 20) and Cervical Jiaji (EX-B 2) points, whereas rabbits in the laser needle-knife group were treated with laser needle-knife targeting the Jiaji points near the C5 spinous process. Rabbits in the normal control and model groups were fixed using similar methods. Behavioral characteristics of all rabbits were evaluated before and after treatment. Peak systolic velocity (PSV) of the right carotid and vertebral arteries in each group were examined using beside B ultrasound, and PI-3K, AKT, VEGF mRNA expression in vertebral arteries were determined by real-time PCR.

Results

The behavioral signs of rabbits were improved after treatment in both the acupuncture and laser needle-knife groups. In comparison with control group, PSV of right carotid arteries in acupuncture group and laser needle-knife group were enhanced significantly (P?<?0.05 and P?<?0.01), PSV of right vertebral arteries in acupuncture group and laser needle-knife group were enhanced significantly too (P?<?0.01 and P?<?0.05). PI-3K mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01, P?<?0.05). AKT mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group (P?<?0.01). VEGF mRNA expression in laser needle-knife and acupuncture group was significantly higher than that in control group too (P?<?0.01, P?<?0.05). No significant differences were found in PI-3K, AKT and VEGF mRNA expression levels among acupuncture and laser needle-knife groups (P?>?0.05).

Conclusion

Laser needle-knife could effectively intervene the mRNA expression of PI-3K, AKT and VEGF, this may be one of the mechanisms of the effect of laser needle-knife in treating CSA in rabbits.  相似文献   
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