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11.
改良热硼酸法高效提取苹果果实RNA   总被引:17,自引:1,他引:17  
苹果果实、尤其是成熟期的果实中多糖和其他次生物质含量高,难以提取RNA。对此,在原热硼酸法的基础上进行了改进,通过添加提取辅助剂并根据辅助剂特性调整提取步骤,高效、稳定地从苹果果实、尤其是后期果实中提取到了高质量的RNA。所得RNA的A260/A230大于2.0,A260/A280为1.8-2.1,并且RNA产量高,其中前期果实RNA产率在13.40μg/g以上,后期果实RNA产率在7.02μg/g以上,完全可以满足RT-PCR、cDNA-AFLP等分子生物学实验的要求。  相似文献   
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AIM: The purpose of the present study was to explore the relationship between interleukin-6 mRNA expression and endometriosis. METHODS: Using the rat model, IL-6 mRNA expression in the endometrium was examined by RT-PCR. RESULTS: The expression of IL-6 mRNA in control rats did not change at 2, 4, 6 and 8 weeks after sham operation (P>0.05), but in model rats it gradually increased at 2, 4, 6 and 8 weeks after endometriosis (P<0.01). The expression of IL-6 mRNA in uterine endometrium with endometriosis was lower than in endometriotic tissue, but higher than in endometrium from healthy controls. CONCLUSION: The IL-6 mRNA expression may contribute to the development of endometriosis . The increase in IL-6 mRNA expression may promote the implantation and growth of endometriotic tissue.  相似文献   
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两种一步法RNA提取试剂的比较   总被引:2,自引:0,他引:2  
RNA的提取在生物医学研究和临床检测上应用广泛。本文分别用进口Invitrogen公司生产的以及我们自己研制的一步法RNA提取试剂,提取大肠杆菌RNA、鸡肌肉组织RNA和尿囊液RNA,通过核酸电泳和荧光定量RT-PCR进行比较。结果表明用我们自己研制的和进口的试剂提取的RNA都不含有DNA;这些RNA都可以作为模板进行RT-PCR检测,并且在数量上相互之间没有明显差异。说明我们自己研制的一步法RNA提取试剂可以取代进口试剂。此外,本文还讨论了此类试剂一些评定方法。  相似文献   
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Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha‐neoendorphin)‐ and pro‐opiomelanocortin (adrenocorticotrophin hormone (18–39) (ACTH), beta‐endorphin (1–27))‐derived peptides. No peptidergic‐immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha‐neoendorphin, ACTH or beta‐endorphin (1–27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro‐opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha‐neoendorphin (1–27)), 18.18% (for ACTH) and 13.95% (for beta‐endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep‐waking cycle and the control of pain transmission.  相似文献   
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Osteochondrosis (OC) is an injury to cartilage canals with a following necrosis in the growth cartilage, from there it can develop to osteochondrosis dissecans (OCD). Due to its high impact in the equine industry, new insights into predisposing factors and potential high‐risk genetic variants are warranted. This article reviews advancements in quantitative and molecular genetics in refining estimation of genetic parameters and identifying predisposing genetic loci. Heritabilities were highest for hock OC with estimates at 0.29–0.46 in Hanoverian warmblood and Norwegian trotters, whereas in Thoroughbreds only very low genetic variation seemed to be present in hock OC lesions. Whole genome scans using the Illumina Equine SNP50 or SNP70 Beadchip were performed in Thoroughbred, Standardbred, French and Norwegian trotter, Hanoverian and Dutch warmblood. Validation studies in Spanish Purebred and Hanoverian warmblood horses corroborated OC risk loci on ECA 3, 14, 27 and 29. Particularly, a strong association with hock‐OCD was found for a single nucleotide polymorphism (SNP) on horse chromosome (ECA) 3 upstream to the LCORL gene. Gene expression and microRNA analyses may be helpful to understand pathophysiological processes in equine OC and to connect OCD‐associated genomic regions with potential candidate genes. Furthermore progress in elucidating the underlying genetic variants and pathophysiological changes in OC may be expected from whole genome DNA and RNA next‐generation sequencing studies.  相似文献   
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