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利用微卫星标记对宁强矮马和蒙古马遗传多样性的研究 总被引:2,自引:0,他引:2
通过8个微卫星位点的多态性检测对宁强矮马和蒙古马共83个个体进行了遗传多样性分析。计算各微卫星位点的等位基因频率、有效等位基因数(Ne)、多态信息含量(PIC)、杂合度(H)和F统计量。结果表明:8个微卫星座位中HMS2变异最大,HTG6变异最小;蒙古马的Ne、PIC、H的平均值均高于宁强马;总群体的平均遗传分化系数Fst为0.017(P<0.01),群体内近交系数Fis为0.171(P<0.01)。说明蒙古马和宁强矮马虽外形和性能上有很大差异,但在品种形成和进化上有着较近的遗传关系。 相似文献
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Simontacchi C Perez de Altamirano T Marinelli L Angeletti R Gabai G 《Veterinary research communications》2004,28(6):467-477
The aim of this work was to investigate the secretion of dehydroepiandrosterone (DHEA), testosterone (T), dihydrotestosterone (DHT) and oestradiol (E) as biological markers in response to illegal administration of testosterone, 19-nortestosterone (N) and oestradiol, either alone or in combination. Twenty male Friesian calves (age 13-14 months) were allotted to a control group (n = 5), and five experimental groups (n = 3) each. Each experimental animal was repeatedly injected with one of the following hormonal treatments: E, T, N, T+E and N+E. Circulating DHEA, T, DHT and E were determined by radioimmunoassay. The administration of T alone did not induce any variation in plasma DHEA, T, DHT and E, which were similar to those in the control group. In contrast, DHEA, T and DHT were on average significantly lower in the T+E and N-treated groups (p < 0.01), whereas the administration of N+E resulted in the reduction of plasma T and DHT without any modification of plasma DHEA. The administration of E alone or in combination increased circulating levels of E but did not affect androgen plasma profiles. The results indicate that plasma levels of T do not permit detection of illegal treatments because plasma androgens always remained within the physiological range. Illegal E treatment could be detected in blood samples when they were collected at least every 20 days. 相似文献
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Sara J. Bruce BVMS W.G. GUILFORD BVSc PhD Duncan I. Hedderley Miho Mccauley 《Veterinary radiology & ultrasound》1999,40(5):472-476
Ten healthy dogs were fed 30 1.5 mm and 10 5 mm radiopaque markers (BIPS, MedID, Grand Rapids) mixed with sufficient quantities of a high fibre diet to meet 25% of their estimated daily caloric requirements. Abdominal radiographs were made at two hour intervals until 90% of the small and large markers had left the colon. The mean residence times (MRT) of each size of marker in the proximal, distal and total colon were calculated using kinetic analysis. The MRT's of the small markers were 4.9 hours (SD 4.4), 7.1 hours (SD 3.3) and 12.0 hours (SD 7.1) respectively. The MRT's of the large markers were not significantly different from the small markers except in the proximal colon where they were significantly shorter (3.2 hours, SD 2.3). Reference colonic filling and colonic transit curves for both sizes of markers were constructed. These may be useful to detect abnormal colonic transit in dogs. 相似文献
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A three‐dimensional cell culture system as an in vitro canine mammary carcinoma model for the expression of connective tissue modulators 下载免费PDF全文
T. C. Cardoso S. S. Sakamoto D. Stockmann T. F. B. Souza H. L. Ferreira R. Gameiro F. V. Vieira M. J. Q. Louzada A. L. Andrade E. F. Flores 《Veterinary and comparative oncology》2017,15(2):582-593
In this study, derived complex carcinoma (CC) and simple carcinoma (SC) cell lines were established and cultured under two‐dimensional (2D) and three‐dimensional (3D) conditions. The 3D was performed in six‐well AlgiMatrix? (LifeTechnologies®, Carlsbad, CA, USA) scaffolds, resulting in spheroids sized 50–125 µm for CC and 175–200 µm for SC. Cell viability was demonstrated up to 14 days for both models. Epidermal growth factor receptor (EGFR) was expressed in CC and SC in both systems. However, higher mRNA and protein levels were observed in SC 2D and 3D systems when compared with CC (P < 0.005). The connective tissue modulators, metalloproteinases‐1, ‐2, ‐9 and ‐13 (MMPs), relaxin receptors 1 and 2 (RXR1 and RXR2) and E‐cadherin (CDH1) were quantitated. All were upregulated similarly when canine mammary tumour (CMT)‐derived cell lines were cultured under 3D AlgiMatrix, except CDH1 that was downregulated (P < 0.005). These results are promising towards the used of 3D system to increase a high throughput in vitro canine tumour model. 相似文献
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