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31.
To study the expression pattern of THBS3 gene in different tissues and during skeletal muscle development, the THBS3 gene expression in different tissues and skeletal muscles during prenatal periods (33, 45, 65, 70 and 90 d) and postnatal periods (0, 9, 30, 60, 120 and 160 d) from Landrace and Tongcheng pigs were detected by Real-time quantification PCR.The results showed that THBS3 gene widely expressed in all tissues examined, exhibiting similar spatial expression patterns with expression peaks in lung in both pig breeds except in stomach and intestine.Moreover, although THBS3 gene showed a significant higher expression level in gestation than after birth in Landrace and Tongcheng pigs (P<0.05), it exhibited different expression patterns between Landrace and Tongcheng pigs, the expression peak was detected at gestation day 45 in Landrace pig, while was detected at gestation day 65 in Tongcheng pig.The results suggested that THBS3 gene involved in skeletal muscle growth and development in pigs, as well as the regulation of asynchronization of skeletal muscle development in different pig breeds. 相似文献
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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
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Two single nucleotide polymorphisms in the promoter of the ovine myostatin gene (MSTN) and their effect on growth and carcass muscle traits in New Zealand Romney sheep 下载免费PDF全文
J. Wang H. Zhou J. Hu S. Li Y. Luo J.G.H. Hickford 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2016,133(3):219-226
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
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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
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Adin DB Diley-Poston L 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):737-741
BACKGROUND: Papillary muscle hypertrophy can occur in conjunction with, or as the only indication of, hypertrophic cardiomyopathy or other diseases that result in left ventricular concentric hypertrophy (LVCH). Assessment of papillary muscle size is usually subjective because objective measures have not been reported. HYPOTHESIS: The study hypothesis was that papillary muscle dimensions are different between normal cats and cats with LVCH. ANIMALS: Echocardiograms from 44 normal cats and 40 cats with LVCH were included in the study. METHODS: All measurements were taken from the right parasternal short-axis view at the level of the papillary muscles at end-diastole. Three methods were used to assess papillary muscle size: the area subtraction method, the direct area trace method, and the diameter method. Measurements were compared between cat groups and method comparisons were made among methods for area determination. RESULTS: Cats with LVCH were older and had significantly greater left ventricular septal and free wall thicknesses and larger left atrial measurements than normal cats (P < .0006). Papillary muscle measurements were significantly greater by all measurement methods in cats with LVCH than in cats with normal echocardiograms (P < .0001). The area subtraction method and direct area trace method showed moderate agreement. CONCLUSIONS AND CLINICAL IMPORTANCE: Papillary muscle measurements were larger for LVCH cats than normal cats; however, some overlap was present. The establishment of these objective measures adds to the echocardiographic examination of cats. 相似文献
37.
Johansson AM Gardner SY Atkins CE LaFevers DH Breuhaus BA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):302-307
BACKGROUND: Recurrent airway obstruction (RAO) is common in horses. Although pulmonary artery (PA) pressure increases during RAO, cardiac function in horses with RAO has received limited attention. HYPOTHESIS: The purpose of this study was to noninvasively determine the cardiovascular effects of acute pulmonary obstruction (APO) in horses with RAO and their reversibility. ANIMALS: Five geldings with RAO, inducible by exposure to moldy hay, were studied. METHODS: Pulmonary mechanics, echocardiography, serum troponin I concentrations, arterial blood gases, and hematocrit were obtained before and after 7 days of APO. Heart rate, PA diameter and flow characteristics, right and left ventricular luminal dimensions and wall thicknesses, global cardiac performance, and evidence of myocardial damage were evaluated. Pulmonary mechanics and echocardiography were reevaluated during remission. RRESULTS: Severe, transient APO did not induce chronic cor pulmonale in horses, because cardiac anatomy and function were normal between episodes. An acute episode of APO produced anatomical and functional cardiac changes in both the right and left heart (including increased PA diameter, abnormal septal motion, and decreased left ventricular diameter and estimated stroke volume), possibly because of the development of pulmonary hypertension, without apparent myocardial damage. The decrease in stroke volume was offset by the increase in heart rate. CONCLUSIONS AND CLINICAL IMPORTANCE: With APO of 7 days' duration, cardiovascular abnormalities and the functional airway changes that produce them are reversible when the offending allergens are removed. 相似文献
38.
AIM To investigate the effects of 17β-estradiol (E2) treatment on the mesenteric lymphatic microcirculation and isolated lymphatic contractility in rats after hemorrhagic shock, and to explore the relationship between contractility and the difference between intra- and extracellular calcium ion concentrations ([Ca2+]) of lymphatic smooth muscle cells (LSMCs). METHODS Male Wistar rats were divided into sham group, shock group and shock+E2 group. The rats were subjected to hemorrhage [(40±2) mmHg for 90 min] and resuscitation with or without subcutaneous injection of E2 (2 mg/kg). After resuscitation for 3 h, the mesenteric lymphatic microcirculation in vivo was observed. Moreover, the isolated mesenteric microlymphatic rings were prepared for the observations of lymphatic contractility evaluated by the indexes including end-systolic diameter, end-diastolic diameter, contraction frequency (CF) and passive diameter. Meanwhile, the difference between intra- and extracellular [Ca2+] of LSMCs was recorded during lymphatic contraction. RESULTS Treatment with E2 significantly enhanced the CF, total contractile fraction and lymphatic dynamics index in vivo in the rats after hemorrhagic shock, and increased the CF, the fractional pump flow and the difference between intra- and extracellular [Ca2+] of LSMCs in isolated lymphatics from the shocked rats (P <0.05). CONCLUSION Estrogen treatment enhances lymphatic contractility in rats after hemorrhagic shock, which is related to enhancement of difference between intra- and extracellular [Ca2+] of LSMCs. 相似文献
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选择了4种家鱼作指示生物,用紫外分光光度法测定其白肌中RNA和DNA的含量。结果表明:同种鱼,污染区的RNA含量显著低于对照区,白鲢和鳊鱼白肌中RNA/DNA低于对照区;不同种的鱼,污染区鱼肌核酸比对照区下降的程度有鳊鱼>白鲢>鲫鱼和鲤鱼的趋势。鱼肌核酸下降同水体重金属污染有一定联系,RNA是比RNA/DNA更合适的指标,鳊鱼和白鲢是比鲫鱼和鲤鱼更敏感的指示生物。 相似文献