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51.
资源植物藏茵陈的研究进展 总被引:8,自引:0,他引:8
本文对藏茵陈资源以及藏茵陈在分子生物学、指纹图谱、胚胎学、组织培养等方面的研究进展进行了综述。 相似文献
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本文简要介绍了遗传学当中的连锁分析方法的历史,现状及其近几十年的发展,并对这些方法的优缺点进行了评价。 相似文献
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Hodgkinson JE 《Veterinary parasitology》2006,136(2):109-116
The future implementation of improved and sustainable control strategies for the major equine parasites will be dependent on a greater insight into their basic biology, pathogenicity and epidemiology together with an enhanced ability for accurate diagnosis. This paper will provide a review of the current molecular methods under development for the detection of equine parasites and their application to current scientific questions. In particular, the strongyles are recognised as important pathogens of horses and recent advances made in the study of this parasitic group at the single species level will be addressed. The ribosomal (r)DNA region of the parasite genome has been employed to distinguish between closely related species. Molecular probes designed to this target region were used in combination with PCR technology to allow the identification of individual species within mixed infections. They have been applied to all parasite stages to look at the role of individual species in natural infection, disease and drug resistance. Similar techniques have been developed to detect other equine parasites and these will also be discussed. Further opportunities for employing existing techniques and the need for new diagnostic tools will be highlighted. 相似文献
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Y. Forcada A. Holder D.B. Church B. Catchpole 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):458-464
Background
Feline diabetes mellitus (DM) shares many pathophysiologic features with human type 2 DM. Human genome‐wide association studies have identified genes associated with obesity and DM, including melanocortin 4 receptor (MC4R), which plays an important role in energy balance and appetite regulation.Hypothesis/Objectives
To identify single nucleotide polymorphisms (SNPs) in the feline MC4R gene and to determine whether any SNPs are associated with DM or overweight body condition in cats.Animals
Two‐hundred forty domestic shorthaired (DSH) cats were recruited for the study. Of these, 120 diabetics were selected (60 overweight, 60 lean), along with 120 nondiabetic controls (60 overweight and 60 lean). Males and females were equally represented.Methods
A prospective case‐control study was performed. Genomic DNA was extracted from blood samples and used as template for PCR amplification of the feline MC4R gene. The coding region of the gene was sequenced in 10 cats to identify polymorphisms. Subsequently, genotyping by restriction fragment length polymorphism (RFLP) analysis assessed MC4R:c.92C > T allele and genotype frequencies in each group of cats.Results
No significant differences in MC4R:c.92C>T allele or genotype frequencies were identified between nondiabetic overweight and lean cats. In the overweight diabetic group, 55% were homozygous for the MC4R:c.92C allele, compared to 33% of the lean diabetics and 30% of the nondiabetics. The differences between the overweight diabetic and the nondiabetics were significant (P < .01).Conclusions and Clinical Importance
We identified a polymorphism in the coding sequence of feline MC4R that is associated with DM in overweight DSH cats, similar to the situation in humans. 相似文献59.
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鸡沙门氏菌脉冲场凝胶电泳分型研究 总被引:1,自引:0,他引:1
为应用脉冲场凝胶电泳(PFGE)从分子水平上对禽源沙门氏菌之间的差别进行分析和研究,本研究采用自动微生物鉴定仪对12株疑似鼠伤寒沙门氏菌和15株疑似鸡白痢沙门氏菌进行了鉴定.以限制性核酸内切酶Xba I对其全基因组DNA进行酶切、PFGE分型,Info Quest FP聚类分析软件对电泳结果进行分析.结果显示,共鉴定出11株鼠伤寒沙门氏菌、1株圣保罗沙门氏菌、6株阿姆斯特丹沙门氏菌、5株亚拉巴马沙门氏菌、1株鸡白痢沙门氏菌、2株纽波特沙门氏菌和2株肠炎沙门氏菌,一共分为12个PFGE型.实验结果表明,江苏地区存在有不常见的沙门氏菌血清型,同种血清型之间的基因型差别较小(相似值为0.85~1),不同血清型之间差别较大(相似值为0.45~0.70).PFGE能从分子水平上对禽源沙门氏菌的基因组DNA进行分型. 相似文献