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1.
The absence or presence of metastases on thoracic radiographs in 55 female dogs with mammary gland tumors was assessed by comparing the results of a single radiographic examination, using dorsoventral and left lateral views, with clinical and histologic follow-up data. Radiographic abnormalities found in dogs with thoracic metastases were classified as well-defined pulmonary nodules, ill-defined pulmonary nodules, and involvement of pleural effusion. No obvious difference in the effect on the right or left lung lobes was found. The sensitivity, specificity and accuracy for the detection of thoracic metastases were 65%, 97%, and 87%, respectively.  相似文献   
2.
Primary bovine mammary epithelial cells (BMECs) were treated by 0, 37.5, 75, 112.5, 150 μmol/L trans10, cis12 conjugated linoleic acid (CLA) to evaluate the effects of different level trans10, cis12 CLA on lipogenesis in BMEC. Addition of 75–150 μmol/L trans10, cis12 CLA reduced significantly the triacylglycerol (TAG) content (P < 0.05), but did not have inhibiting action on cell proliferation (P > 0.05). Treatment with 150 μmol/L trans10, cis12 CLA for 48 h resulted in a 17.1% reduction (P < 0.0001) of medium chain fatty acids (MCFA, C14 < C < C16), a 26.5% reduction (P < 0.0001) of unsaturated fatty acids (UFA) and a corresponding reduction of the mRNA abundance of acetyl coenzyme A (acetylCoA) carboxylase (ACC) (P = 0.046), fatty acid synthase (FAS) (P = 0.017) and stearoylCoA desaturase1 (SCD1) (P = 0.002). Another finding was that trans10, cis12 CLA elevated expression of diacylglycerol acyltransferase2 (DGAT2) (P = 0.020) and long chain acylCoA synthetases (ACSL) (P = 0.032). In conclusion, higher trans10, cis12 CLA, not low trans10, cis12 CLA, inhibited milk fat synthesis and changed fatty acid composition by regulating the expression of FAS, ACC, SCD1, DGAT2 and ACSL.  相似文献   
3.
本试验研究了阴外动脉灌注乳脂前体物对奶牛产奶量及乳腺内短链脂肪酸摄取规律的影响。选择8头健康荷斯坦奶牛分为2组,每组4头牛。采用2×2交叉试验设计,2组分别饲喂2种不同粗饲料[苜蓿(MF组)、玉米秸秆(CS组)]的饲粮,饲粮的精粗比为45∶55。试验分为2阶段,每阶段20 d,其中预试期14 d,载体灌注期3 d,乳脂前体物灌注期3 d。在载体灌注期,MF组与CS组均接受载体灌注,分别命名为MFC_1组和CSC组;在乳脂前体物灌注期,MF组继续接受载体灌注(MFC_2组),CS组灌注乳脂前体物(CSF组)。测定产奶量、干物质采食量及乳成分。采集尾动脉和乳静脉血浆测定短链脂肪酸浓度和脂肪酸比例。结果表明:1)在灌注乳脂前体物前,CSC组产奶量、4%乳脂校正乳产量、乳脂产量、乳蛋白产量和产乳脂效率显著低于MFC_1组(P0.05),CSC组尾动脉血浆中短链脂肪酸浓度及短链脂肪酸/长链脂肪酸有低于MFC_1组的趋势(0.05≤P0.10)。2)灌注乳脂前体物后,CSF组产乳脂效率和乳蛋白率显著高于CSC组(P0.05),CSF组产奶量、4%乳脂校正乳产量、乳脂率和乳蛋白率尽管在数值上仍然低于MFC_2组,但组间差异不显著(P0.05),而CSF组产乳脂效率显著高于MFC_2组(P0.05)。3)灌注乳脂前体物后,CSF组尾动脉血浆中乙酸、丙酸以及短链脂肪酸浓度显著高于CSC组(P0.05),且乙酸、丁酸及短链脂肪酸浓度显著高于MFC_2组(P0.05),短链脂肪酸/长链脂肪酸有低于MFC_2组的趋势(0.05≤P0.10)。4)除CSF组丁酸动静脉差有高于CSC组的趋势(0.05≤P0.10)外,CSC组与MFC_1组、CSC组与CSF组、CSF组与MFC_2组乳腺对乙酸、丙酸、丁酸、短链脂肪酸的摄取量、摄取率和动静脉差均无显著差异(P0.05)。结果提示,以玉米秸秆为粗饲料奶牛灌注乳脂前体物可显著增加奶牛的产奶量、乳脂率和乳脂产量,并达到与以苜蓿等为粗饲料相似的水平,且具有较高的产乳脂效率,但对乳腺内短链脂肪酸的摄取量和摄取率无显著的影响。  相似文献   
4.
试验旨在研究果香味剂对奶牛乳腺上皮细胞培养液中乳成分含量及培养液风味的影响。试验选用自制的奶牛乳腺上皮细胞,设5个处理组,果香味剂的添加剂量分别为0、5、10、15和20μg/mL。结果表明:①当培养基中果香味剂添加量为15μg/mL时,乳腺上皮细胞培养液中总蛋白水平、甘油三酯及乳糖含量均达到最高,其中对脂肪含量影响显著(P<0.05),而对蛋白和乳糖含量影响不显著(P>0.05),之后呈下降趋势,说明果香味剂可能会诱导奶牛乳腺上皮细胞乳蛋白、乳脂和乳糖分泌水平的升高;②运用PT/GC-MS分析乳腺培养液中的风味成分,与对照组相比,各试验组中除具有原有乳腺培养液的风味外,还有乙酸异丁酯、乙酸异戊酯、丙酸异戊酯、丙酸戊酯、丁酸异丁酯、丁酸戊酯、丁酸乙酯、邻苯二甲酸二异丁酯等物质成分,而这些物质成分正好是果香味剂中进入到乳腺培养液中的风味物质,且当添加剂量为15μg/mL时,各物质成分含量为最高(P<0.05),之后呈下降趋势。果香味剂能显著影响奶牛乳腺上皮培养液中乳成分含量和风味。  相似文献   
5.
蔡萌  南雪梅  熊本海  杨亮 《畜牧兽医学报》2020,51(12):2934-2941
脂类是一种可以为动物体储存和提供能量的物质,大量研究证实,日粮中脂类的改变可以改变microRNAs(miRNAs)的表达从而影响机体生命活动。本综述主要概括了脂肪酸对奶牛乳腺miRNAs的调控作用,从奶牛乳腺miRNAs表达特征、调控乳脂合成的miRNAs及外源添加脂肪酸对乳腺miRNAs的调控三个方面进行概述,旨在从转录后调控角度,建立营养物质与乳腺功能的联系,为未来相关研究提供参考。  相似文献   
6.
To develop the potential function of dairy cow mammary stem cells (DCMECs) in regulation of lactation,we identify putative DCMECs which were BrdU label retaining epithelial cells,at the same time,analysis the location of two new mammary stem cells molecular marks FNDC3B and PROCR to verify the feasibility of them to indicate DCMECs.The mRNA levels of prolactin,growth hormone,insulin-like growth factor-1 and their receptors were detected along with cell passage by Real-time quantitative PCR.The results showed that the proportion of BrdU label-retaining epithelial cells was nearly 0.4% after 25 d continuous culture (passaged 4 times) and few cells were positive for FNDC3B or PROCR.Moreover,we observed the BrdU labelled epithelial cells by asymmetric division.The mRNA levels of prolactin,growth hormone,insulin-like growth factor-Ⅰ and their receptors in primary and passage cells were extremely significant difference(P<0.01).DCMECs would rapidly lose some physiological characteristics and the ability of milk synthesis when not under the condition of induction of lactation differentiation,but a certain percentage of mammary stem/progenitor cells will be retained,whose potential effects on the regulation of lactation and mammary acinar remodeling were worthy of attention.  相似文献   
7.
8.
A 9-year-old female sugar glider (Petaurus breviceps) was evaluated for a tissue mass near the marsupium. Ultrasonography identified a vascular mass originating from the right mammary gland. Fine-needle aspiration was suggestive of a malignant neoplasm. The glider was anesthetized and the tumor was removed, and this was followed by strontium-90 plesiotherapy to the tumor bed in an attempt to decrease local recurrence. Histopathology revealed an anaplastic mammary carcinoma. The glider was euthanized less than 14 days after the procedure owing to self-mutilation behavior of unknown etiology. This report is the first to describe the clinical presentation, diagnostics, therapeutics, and treatment response for a sugar glider with mammary neoplasia.  相似文献   
9.
Buffalo mammary epithelial cell,cumulus cell and fibroblasts were transfected by adenovirus vectors and compared their transfection efficiency.293 cells were transfected with pBHGloxdelE13cre and pDC316-eGFP by liposome,the virus was collected and titer was detected.Buffalo mammary epithelial cell,cumulus cell and fibroblasts were exposed to different multiplicity of infection (MOI) of adenovirus vectors.After 72 h,the cells were observed with inverted fluorescence microscope,and transfection efficiency was calculated.When the MOI was 25,50,100,200 and 400,the transfection efficiency of fibroblasts were 0.7%,7.0%,9.0%,12.5% and 34.0%,the transfection efficiency of cumulus cells were 42.5%,55.3%,57.4%,76.0% and 80.0%,the transfection efficiency of mammary epithelial cells were 88.7%,100%,100%,100% and 100%.The results showed that the transfection efficiency of mammary epithelial cell was the best,followed by cumulus cell,and fibroblast was poor.  相似文献   
10.
In the dairy cow, negative energy balance affects milk yield and composition as well as animal health. Studying the effects of negative energy balance on dairy cow milk production is thus essential. Feed restriction (FR) experiments attempting to reproduce negative energy balance by reducing the quantity or quality of the diet were conducted in order to better describe the animal physiology changes. The study of FR is also of interest since with climate change issues, cows may be increasingly faced with periods of drought leading to a shortage of forages. The aim of this article is to review the effects of FR during lactation in dairy cows to obtain a better understanding of metabolism changes and how it affects mammary gland activity and milk production and composition. A total of 41 papers studying FR in lactating cows were used to investigate physiological changes induced by these protocols. FR protocols affect the entire animal metabolism as indicated by changes in blood metabolites such as a decrease in glucose concentration and an increase in non-esterified fatty acid or β-hydroxybutyrate concentrations; hormonal regulations such as a decrease in insulin and insulin-like growth factor I or an increase in growth hormone concentrations. These variations indicated a mobilization of body reserve in most studies. FR also affects mammary gland activity through changes in gene expression and could affect mammary cell turnover through cell apoptosis, cell proliferation, and exfoliation of mammary epithelial cells into milk. Because of modifications of the mammary gland and general metabolism, FR decreases milk production and can affect milk composition with decreased lactose and protein concentrations and increased fat concentration. These effects, however, can vary widely depending on the type of restriction, its duration and intensity, or the stage of lactation in which it takes place. Finally, to avoid yield loss and metabolic disorders, it is important to identify reliable biomarkers to monitor energy balance.  相似文献   
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