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131.
132.
A 14‐year‐old neutered male Dachshund presented for the evaluation of oculus dexter (OD) third eyelid elevation ongoing for approximately 2 months. Complete ophthalmic examination revealed a large, nonpainful, well‐demarcated, soft mass at the base of the right third eyelid causing elevation and mild hyperemia. The mass was freely moveable with the third eyelid, and no right globe deviation was noted. No other abnormalities were noted on physical examination, routine blood chemistry, complete blood count, serum T4, urinalysis, or urine cortisol/creatinine ratio. Ocular B‐mode ultrasonography showed an anechoic, well‐demarcated, homogenous, soft tissue mass at the base of the third eyelid with no orbital extension. A leiomyoma was diagnosed after multiple punch biopsies were obtained from the palpebral surface of the mass. The right third eyelid was excised surgically. Histopathology confirmed a completely excised, nodular, unencapsulated, expansile mass within the third eyelid. Positive smooth muscle actin and negative S‐100 immunohistochemistry confirmed a leiomyoma. Bundles of normal smooth muscle were also present adjacent to the mass. The mass was compressing the adjacent lacrimal gland and associated with moderate dacryoadenitis. Twelve months postoperatively, the right globe position and motility remain normal with no evidence of mass regrowth. To the author's knowledge, this is the first reported case of a leiomyoma of the third eyelid in any species. In this case, the mass was completely excised and no regrowth has occurred twelve months after surgery. This case along with independently reviewed canine third eyelids clearly demonstrates the presence of smooth muscle within the canine third eyelid.  相似文献   
133.
134.
Myostatin is a negative regulator of muscle growth and development in mammals, and variation in ovine myostatin gene (MSTN) has been demonstrated to be associated with variation in the muscularity of sheep. Polymerase chain reaction–single‐stranded conformational polymorphism (PCR–SSCP) was used to look for single nucleotide polymorphisms (SNPs) in a 304‐bp amplicon from the promoter region of ovine MSTN. Sequence analyses revealed two previously identified SNPs (c.?2449G/C and c. ?2379T/C) that resulted in three haplotypes (H1 (c.[?2449G; ?2379C]), H2 (c.[?2449C; ?2379C]) and H3 (c.[?2449G; ?2379T]). The effect of these SNPs on growth and carcass traits was investigated in 357 NZ Romney lambs. General linear mixed‐effect models revealed that sheep with the genotype c.?2449GC had a higher loin meat yield (p = 0.032) and proportion loin yield (p = 0.028), than those with the genotype c.?2449GG. The genotype c.?2379CC was associated with an increase in three weight traits: birthweight (p = 0.003), tailing weight (p = 0.009) and weaning weight (p = 0.028), when compared with the genotype c.?2379TC, but it was not found to have an association with growth rate. This suggests that c.?2379T/C has an effect that originates at, or before birth. Haplotype H3 was associated with a decrease in birthweight (p = 0.002), tailing weight (p = 0.003) and weaning weight (p = 0.011). Haplotype H2 was associated with increased loin yield (p = 0.012) and proportion loin yield (p = 0.002). The SNPs may have value as genetic markers for improved Romney breeding.  相似文献   
135.
Growth hormone (GH) plays a specific role to inhibit apoptosis in the bovine mammary gland through the insulin-like growth factor (IGF)-I system, however, the mechanism of GH action is poorly understood. In this study, we show that GH dramatically inhibits the expression of IGFBP-5, and GH along with IGF-I enhanced the phosphorylation of Akt through the reduction of IGF binding protein (IGFBP)-5. To determine how GH affects Akt through IGF-I in bovine mammary epithelial cells (BMECs), we examined the phosphorylation of Akt in GH treated BMECs and found that IGF-I induced phosphorylation of Akt was significantly enhanced by the treatment with GH. We demonstrated that GH reduces mRNA and protein expression of IGFBP-5 in BMECs, but it does not affect the expression of IGFBP-3. To determine that the enhanced effect of the Akt phosphorylation by the treatment of GH is due to the inhibition of the expression of IGFBP-5, we examined the effect of IGFBP-3 and -5 on the phosphorylation of Akt through IGF-I in the GH-treated BMECs. The phosphorylation of Akt was inhibited in a dose-dependent manner when IGFBP-5 was added at varying concentrations and was also inhibited in the presence of IGFBP-3. The results of this study suggest that GH plays an important role on mammary gland involution in bovine mammary epithelial cells.  相似文献   
136.
本研究旨在比较不同生长阶段隔日限饲(早期限饲:1~14日龄限饲,后期限饲:50~63日龄限饲)对肉鸡肌肉生长及相关激素水平的影响,并探讨早期限饲对肉鸡肌肉生长的程序化作用。试验结果:1)早期限饲组整个试验阶段体重均极显著低于对照组,后期限饲组限饲一周后体重显著低于对照组并于63日龄实现完全补偿生长;2)早期限饲组14日龄和63日龄胸肌、腓肠肌重均显著低于对照组;后期限饲组63日龄胸肌、腓肠肌重均显著低于对照组,且二者与早期限饲组均差异不显著;3)早期限饲显著降低了14日龄肉鸡肌肉中DNA、RNA和蛋白含量,63日龄恢复至正常水平,且核酸、蛋白水平在胸肌和腓肠肌内的趋势表现不一致;4)早期限饲组14日龄血清中T3、T4水平均显著低于对照组,63日龄血清T3水平仍显著低于对照组;后期限饲组63日龄血清T3水平显著低于对照组,T4水平与对照组差异不显著。结果表明:1)限饲可显著阻碍肉鸡肌肉的生长;2)不同部位的肌肉对限饲的敏感度不同;3)早期营养因子对肉鸡肌肉的生长具有"程序化"作用,甲状腺激素可能参与这些过程的调节。  相似文献   
137.
为对鼠源细胞进行鉴别检测,以鼠线粒体16S rRNA基因序列为靶位点设计特异性引物及探针,建立实时荧光定量PCR检测方法,并评价该方法的特异性及敏感性。结果显示,所建立的检测方法特异性好,针对鼠源细胞基因组荧光定量PCR扩增曲线良好,其他物种来源细胞基因组及生物制品原辅材料未出现特异性扩增曲线;敏感性高,基因拷贝数检出限度为45.3拷贝。本试验建立的荧光定量PCR检测方法能够有效地对鼠源细胞进行快速检测,为细胞质量控制提供了有效方法。  相似文献   
138.
The paper researches on the degradation of LAS (Linear Alkyl benzene Sulphonate) by combining AS1.860 immobilized with low intensity ultrasonic irradiation. The paper also discusses the influence of pH, rotary velocity, LAS concentration and the condition of low intensity ultrasonic irradiation on the degradation of LAS, the degradation rate of LAS is the main index of our experiment, the results of orthogonal test shows that low ultrasonic irradiation can increase the metabolizing of microorganism cells and facilitate the biodegradation of immobilized cells to LAS, here we research the degradation condition of 50mg/L LAS simulation wastewater with low ultrasonic irradiation, and the results show that the influence is obvious, the optimization degradation rate is about 83%, nine point five percent higher than that of the immobilized cells without ultrasonic irradiation.  相似文献   
139.
The influenfial factors of stratification plane to smooth blasting are studied according to the ti eory of smooth blasting and the anslysis of static stress. The results show that the angle p between the maximum principal plane and the rertical line of stratification plane has some influence on the fracture of rock masses.  相似文献   
140.
目的是研究内毒素(lipopolysaccharide; LPS)导致肠黏膜微血管内皮细胞损伤的作用机制。将所培养的肠黏膜微血管内皮细胞分为空白对照组和LPS组,每组按时间分为4个亚组:3h、6h、9h、12h。空白对照组加维持培养液,LPS组加1μg/ml LPS培养液,在CO2培养箱内静置培养。结果表明,一氧化氮(NO)分泌明显升高,3h后达到高峰,随后逐渐降低,而内皮素(endothelin; ET)分泌急剧升高,9h后达到高峰,随后又开始逐渐降低,但一直保持在较高的水平。所以引起了NO和ET的升高可能是LPS导致肠黏膜微血管内皮细胞的损伤机制。  相似文献   
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