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101.
本研究比较了不同的分离方法和酶作用的不同时间,以及不同的卵巢表面状态等因素对水牛小腔卵泡分离效果的影响,以期建立有效的水牛小腔卵泡分离体系。结果发现,采用机械与酶结合的方法分离水牛小腔卵泡时,平均每个卵巢获得5.64个小腔卵泡,显著高于机械法分离平均每个卵巢获得的3.12个小腔卵泡数(P<0.05);当胶原蛋白酶作用12或15 min,每个卵巢平均获得的小腔卵泡数均显著高于5和10 min处理组(P<0.05),两组之间没有显著差异(P>0.05),但当消化时间延长到20 min时,卵泡膜被酶消化而破裂,没法分离到小腔卵泡;从表面小于2 mm卵泡且无黄体的卵巢分离获得的小腔卵泡平均数显著高于表面无可见卵泡且有黄体的卵巢组的平均数(7.50和2.25,P<0.05)。以上结果表明,选用表面无小于2 mm卵泡且无黄体的卵巢,采用机械与酶结合的方法,酶作用时间为12~15 min分离水牛的小腔卵泡,可获得的小腔卵泡数量最多。 相似文献
102.
LI Hui-feng LI Qing-hong LI Hong-quan HAO Rui-rong CHEN Jian-hui GU Jian-wen 《中国畜牧兽医》2015,42(9):2459-2466
The objective of this study was to compare the effect of three Chinese herbal medicine (medicated leaven, hawthorn, fructus hordei germinates) on histomorphology of different parts of small intestine in weaning piglets.40 28-day old ternary pigs (Duroc×Landrace×Yorkshire) with the body weight (8.13±1.32)kg were divided into four groups, control group, medicated leaven group, hawthorn group and fructus hordei germinates group, and feeding with 1% Chinese herbal medicine, there were two repeats in each group and each repeat had 5 piglets, slaughtering and sampling at 7th and 14th day morning, respectively, sections were used for HE staining.The staining tissues were taken pictures under a microscope camera (200×) and measured VH, CD, IWT and V/C in different parts of small intestine with Image-Pro Plus.The result showed that the IWH of ileum in medicated leaven group was significantly or extremely significantly higher than control group (P<0.05;P<0.01).The VH and IWT of duodenum and jejunum at 7th day in hawthorn group were extremely significantly lower than control group (P<0.01);The IWT of ileum and the VH of ileum at 14th day were extremely significantly higher than control group (P<0.01).In fructus hordei germinates group, the VH of duodenum and jejunum at 7th day and IWT of jejunum were extremely significantly lower than control group (P<0.01);The CD of ileum at 7th day, the IWT of duodenum and ileum at 7th day were extremely significantly higher than control group (P<0.01).The effects of different simple Chinese herbal medicine on histomorphology of different parts of small intestine in piglets were different, because of the different digestive functions of small intestine, the most effects of Chinese herbal medicine an duodenum, jejunum and ileum were fructus hordei germinates, medicated leaven and hawthorn, respectively. 相似文献
103.
104.
Impact of source tissue and ex vivo expansion on the characterization of goat mesenchymal stem cells
Background
There is considerable interest in using goats as models for genetically engineering dairy animals and also for using stem cells as therapeutics for bone and cartilage repair. Mesenchymal stem cells (MSCs) have been isolated and characterized from various species, but are poorly characterized in goats.Results
Goat MSCs isolated from bone marrow (BM-MSCs) and adipose tissue (ASCs) have the ability to undergo osteogenic, adipogenic and chondrogenic differentiation. Cytochemical staining and gene expression analysis show that ASCs have a greater capacity for adipogenic differentiation compared to BM-MSCs and fibroblasts. Different methods of inducing adipogenesis also affect the extent and profile of adipogenic differentiation in MSCs. Goat fibroblasts were not capable of osteogenesis, hence distinguishing them from the MSCs. Goat MSCs and fibroblasts express CD90, CD105, CD73 but not CD45, and exhibit cytoplasmic localization of OCT4 protein. Goat MSCs can be stably transfected by Nucleofection, but, as evidenced by colony-forming efficiency (CFE), yield significantly different levels of progenitor cells that are robust enough to proliferate into colonies of integrants following G418 selection. BM-MSCs expanded over increasing passages in vitro maintained karyotypic stability up to 20 passages in culture, exhibited an increase in adipogenic differentiation and CFE, but showed altered morphology and amenability to genetic modification by selection.Conclusions
Our findings provide characterization information on goat MSCs, and show that there can be significant differences between MSCs isolated from different tissues and from within the same tissue. Fibroblasts do not exhibit trilineage differentiation potential at the same capacity as MSCs, making it a more reliable method for distinguishing MSCs from fibroblasts, compared to cell surface marker expression.Electronic supplementary material
The online version of this article (doi:10.1186/2049-1891-6-1) contains supplementary material, which is available to authorized users. 相似文献105.
E. S. Pereira A. B. R. Carmo M. R. G. F. Costa A. N. Medeiros R. L. Oliveira A. P. Pinto M. S. S. Carneiro F. W. R. Lima A. C. N. Campos S. P. Gomes 《Journal of animal physiology and animal nutrition》2016,100(6):1090-1096
In this study, we evaluated the requirements of calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na) and potassium (K) for sheep hair growth. Experimental diets contained different levels of metabolizable energy [ME; 0.96, 1.28, 1.72, 2.18 and 2.62 Mcal/kg of dry matter, (DM), corresponding to 4.23, 5.64, 7.58, 9.61 and 11.55 MJ/kg DM]. The lambs' hair (n = 48) at 2 months of age presented an average body weight (BW) of 12.05 ± 1.81 kg. At the beginning of the experiment, eight animals were slaughtered as a reference group to estimate the initial empty body weight and body composition. Net mineral requirements (g/day) ranged from 0.73 to 0.71 g of Ca, 0.51 to 0.49 g of P, 0.026 to 0.026 g of Mg, 0.16 to 0.19 g of Na and 0.15 to 0.13 g of K for animals with a BW ranging from 15 to 30 kg and a daily gain of 100 g. The results of this study indicate that the net macromineral requirements for weight gain in Morada Nova lambs are different from the values commonly recommended by the Agricultural and Food Research Council. 相似文献
106.
Fractures of the humerus 总被引:2,自引:0,他引:2
Simpson AM 《Clinical Techniques in Small Animal Practice》2004,19(3):120-127
Humeral fractures are the least common long bone fracture in small animals. The low incidence of these fractures combined with the unique anatomy of the humerus makes repair of humeral fractures challenging. This chapter provides a review of humeral fracture management. 相似文献
107.
探讨了在二乙基己烯雌酚(DES)诱发成年动物生精细胞凋亡过程中睾丸一氧化氮(NO)生成和生精细胞一氧化氮合酶(eNOS和iNOs)表达的变化,以期为阐明DES诱发生精细胞凋亡机理的研究提供基础资料。成年雄性仓鼠皮下注射不同剂量DES(分别为0.01、0.1和1mg/kg体重),连续注射7d后取其睾丸,进行NO含量的测定和eNOS、iNOS免疫组化染色。电镜观察生精细胞超微结构的变化,并用TUNEL法检测睾丸中生精细胞凋亡的变化,苏丹Ⅲ染色法检测睾丸生精小管内脂滴分布的变化。结果显示:NO的生成与DES呈剂量依赖性。DES处理后,在1mg/kg体重剂量组,大量生精细胞表达eNOS和iNOS,并出现大量凋亡,退化的生精细胞胞浆内有大量髓样结构,并有大量脂滴分布于生精细胞内和细胞间。eNOS和iNOS阳性生精细胞与凋亡的生精细胞数量和类型基本一致,主要为精母细胞和圆形精子细胞。 相似文献
108.
为探讨人胎盘组织在造血中的作用以及研究造血和神经标志物在胎盘中的表达和在胚胎发育中的相关性,用免疫组织化学法对人胎盘组织和体外培养的胎盘组织中的贴壁细胞进行染色,观察其造血因子和神经标志物的表达。结果发现人7月龄胎盘组织血管内血细胞表达多种造血细胞因子,如SCF、VEGF、BMP-4和FGF-1和KDR,血管内皮细胞上也有表达;胎盘组织同时表达造血干细胞标记CD34、CD133和神经细胞标记物Nestin和MAP2等。而足月龄胎盘CD34、CD133、KDR和造血相关因子SCF、VEGF、BMP-4、FGF-1等弱表达,不表达Nestin和MAP2。两组胎盘切片都不表达GFAP和MBP。胎盘贴壁细胞(hPDACs)碱性磷酸酶、波形蛋白、CD133、Nestin和MAP2染色呈阳性,CD34、GFAP和MBP阴性表达。人胎盘组织和胎盘贴壁细胞表达多种造血相关因子和神经细胞标志物,提示胎盘具有造血功能,造血形成和神经发生之间可能存在基因表达叠加现象。 相似文献
109.
The effect of a water-soluble fraction (WSF) of a non-pathogenic strain of Mycobacterium phlei was studied in bovine subclinical mastitis (SCM) by measuring the myeloperoxidase and acid phosphatase enzyme levels in the milk leukocytes. Forty-five cows were divided into three equal groups. Group I, consisting of 15 healthy cows, served as the control, whereas groups II and III each contained 15 cows with subclinical mastitis on the basis of a positive reaction in the California mastitis test (CMT). The cows in group II received 100 microg of WSF in 5 ml sterile phosphate-buffered saline, pH 7.4 (PBS) once only, while those in group III received 5 ml sterile PBS daily for 7 days, both treatments being given by the intramammary route. Observations were made up to 30 days after treatment (AT). The CMT of the healthy milk was negative (0), whereas it ranged between 1 and 2 points in SCM. The somatic cell count (SCC) increased significantly (p < 0.05) on day 3, then fell steeply from day 7 up to day 30 AT in the cows in group II. A steady decrease in the total bacterial count (TBC) was observed in the group treated with WSF but the bacterial counts remained high in the groups treated with PBS. The mean acid phosphatase level was enhanced by 119% on day 3 AT in group II but only by 18.7% in the cows in group III. The mean myeloperoxidase level was enhanced by 100% in the cows in group II but only by 18% in those in group III on day 3 AT. This significant reduction in the bacterial load in infected cows caused by intramammary infusion of WSF may be due to activation of the microbicidal activity of the neutrophils, but this requires confirmation. 相似文献
110.
Kaminski T 《Domestic animal endocrinology》2004,27(4):379-396
Opioids were found as factors affecting porcine ovarian steroidogenesis. The mechanism of opioid action, however, on porcine theca interna cells is completely unknown. Therefore, the present study was designed to investigate the possible involvement of two intracellular pathways, phospholipase C/protein kinase C and adenylyl cyclase/protein kinase A, in opioid signal transduction in porcine theca cells treated with mu opioid receptor agonist, FK 33-824. Incubation of the cells for 4 h with FK 33-824 at the dose 1 nM resulted in decreases in inositol phosphate accumulation as well as androstenedione (A(4)), testosterone (T), and estradiol (E(2)) secretions. Protein kinase C (PKC) inhibitors, staurosporine (1-100 nM), D-sphingosine (10-500 nM), and PKCi (100-2000 nM), both added alone and together with the opioid agonist, depressed release of the steroid hormones. PKC activator, phorbol ester (PMA, 1-100 nM), used alone was without effect on theca cell steroidogenesis, but added in combination with FK 33-824 abolished inhibitory influence of the opioid on A(4), T, and E(2) output. The steroid hormone secretion by PKC-deficient theca cells was inhibited by the opioid agonist. FK 33-824 also suppressed PKC activity reducing [(3)H]PDBu specific binding to theca cells, whereas ionomycin (a positive control) increased labeled phorbol ester binding to the cells. In the next experiment, cAMP release from theca cells during 2 and 4 h incubations with FK 33-824 (1-100 nM), naloxone (10 microM; opioid receptor antagonist), and LH (100 ng/mL; a positive control) was examined. FK 33-824 at the dose 1 nM inhibited cAMP secretion during 2 h incubation, but had no effect during longer incubation. LH in a manner independent on incubation time multiplied cAMP release. Protein kinase A inhibitor, PKAi (100-2000 nM), alone and in combination with FK 33-824 (1 nM), inhibited A(4), T, and E(2) secretions by theca cells. PKA activator, 8BrcAMP (10-1000 microM), stimulated the steroid hormone release, but this stimulatory effect was diminished in the presence of FK 33-824. The results allow to suggest that opioid peptides affect porcine theca cell steroidogenesis and their acute action on the cells is connected with the inhibition of phospholipase C/protein kinase C and adenylyl cyclase/protein kinase A signal transduction systems. 相似文献