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1.
The formation of placenta at the beginning of pregnancy and its separation at parturition require not only deep remodelling of extracellular matrix, which mainly consists of proteins conjugated with sugar moieties, but also the cooperation with cells from both maternal and foetal parts of placenta. The aim of the study was to compare the patterns of selected conjugated proteins with sugar moieties between pregnant and term placenta as well as between released and retained placenta in cows. Placental samples from healthy pregnant cows (3–5 months of pregnancy) were collected at a slaughterhouse (n = 6), and parturient samples were collected during caesarean section at term and retrospectively divided into retained (n = 6) and released (n = 6). The pattern of selected sugar moieties conjugated with proteins was detected by use of lectin blotting with Phaseolus Vulgaris leucoagglutinin, Maackia Amurensis and Sambucus Nigra (Elderberry). The comparison and analysis of obtained band patterns showed differences between their number, molecular weight and abundance related to the intensity of staining. Samples from 3 to 4 months showed similarities, while at the 5th month, clear differences were visible in all 3 lectins, which were used in this study. Samples from retained/released placenta expressed significant differences in PHA‐L and SNA pattern in the foetal part. Obtained results indicate that the development of placenta related to extracellular matrix and accompanying cells from both sides of placenta shows dynamic changes during pregnancy. Moreover, in the case of animals with the retention of foetal membranes the patterns of proteins conjugated with sugar moieties are altered, suggesting that the changes in extracellular matrix metabolism can be involved in the attachment and detachment of the placenta in cows.  相似文献   

2.
外泌体对哺乳动物妊娠的调控作用   总被引:1,自引:1,他引:0  
外泌体(exosome)广泛存在于各种体液中,其内部包含蛋白质、脂质、mRNA和miRNA等在细胞间进行物质和信息传递的多种生物活性成分,参与调节机体多种生理过程。近年来,研究学者相继发现子宫液、输卵管液、胎盘中也存在外泌体,且证明其可能参与配子发生、受精、胎盘发生、胚胎着床及胎儿发育等生殖过程,进一步加深了人们对哺乳动物妊娠过程的认识,为一些重要的生殖调控机理研究提供了新的思路。因此,本文主要阐述了外泌体的发现、外泌体在哺乳动物妊娠中的作用以及与妊娠疾病关系的最新进展,为进一步揭示外泌体在哺乳动物妊娠中的调控作用提供参考。  相似文献   

3.
哈白猪复旧期子宫内微生物变化的研究   总被引:2,自引:0,他引:2  
本试验采用子宫内膜活检采样器采集子宫内容物样品 ,通过活菌计数、分离鉴定和药敏试验等对实验母猪产后子宫内细菌进行了研究 ,以探讨产后子宫内微生物的变化规律及对子宫复旧的影响。试验结果表明 ,在产后 0~ 1天之间 ,子宫内细菌数量呈直线增加 ,在产后第 7天时 ,子宫内细菌数量达到最多 ,此后其细菌数量逐渐下降 ;到产后第 2 5天时 ,子宫内细菌数量已降为 (7.35± 2 .5 4 )× 10 2个 / mg子宫样品。而细菌的种类在产后 1~ 7天之间较少 ,在产后第 7~ 13天间呈增长趋势 ,产后第 13天以后 ,细菌种类开始减少 ,直至接近于零。这说明产后子宫内环境经历了从污染到净化的过程 ,直至子宫复旧完毕  相似文献   

4.
子宫自然杀伤(uterine natural killer, uNK)细胞是哺乳动物妊娠早期胎盘蜕膜中数量最多的免疫细胞。妊娠期间,uNK细胞对子宫免疫耐受环境建立,胎盘以及胎儿的发育等均具有重要调控作用。目前,有关妊娠中uNK细胞独特生物活性调控机制研究非常缺乏。本文综合相关研究,介绍了妊娠过程中uNK细胞在母-胎免疫耐受建立、胎盘和胎儿发育过程中重要调控作用,并总结激素、糖代谢以及DNA甲基化等对其他组织NK细胞调控机制研究,为探索uNK细胞调控分子机制提供新的研究方向和思路。  相似文献   

5.
应用透射电镜观察两头奶牛产后第1、7、l3、20、26、32、38、45、52、60天的子宫组织的超微结构变化,结果发现:分娩使奶牛部分子宫内膜破损,并且与其相邻的细胞也在产后1~7d内坏死脱落;未破损上皮细胞的纤毛和微绒毛也受到损坏;产后第13天时,基底细胞开始生长以修复分娩时被损坏的子宫内膜,到45d时生长基本完成,产后60d时组织修复完成,纤毛和微绒毛覆盖整个子宫内膜表面。在产后1~7d内,子宫组织内胶原片段多、胶原纤维呈溶解状、横纹不清楚、胶原束内出现空腔;从产后第26天开始胶原纤维片段较少并排列较整齐,而第32天以后胶原纤维束交错整齐排列、横纹清楚、无胶原片段。在产后1~7d内,子宫平滑肌细胞核呈扭曲状、胞质内充满肌丝,并且体积较小;从产后20d开始平滑肌细胞体积增大、胞质内线粒体和高尔基复合体等细胞器增多。产后1~32d之间,子宫组织内巨噬细胞数量增多,其胞质内溶酶体、线粒体等细胞器增多;产后13~32d之间,浆细胞数量增多,其胞质内粗面内质网池扩大、线粒体和高尔基体等细胞器增多;淋巴细胞大量浸润。产后20~45d之间,成纤维细胞数量增加,其胞质内细胞器增多;产后7~45d之间毛细血管周围的周细胞数量增加。  相似文献   

6.
牛产后子宫复旧延迟会延长繁殖间隔,降低繁殖率。子宫复旧涉及产后子宫组织退化、修复与子宫肌层的重塑,其中干细胞、细胞因子与非编码RNA以及雌激素与孕激素等参与调控产后子宫组织修复与再生。同时,维生素与葡萄糖类物质、中药制剂、免疫调节因子等绿色、无公害防治方法能够有效促进牛产后子宫复旧。本文就牛产后子宫复旧调控机制及促进子宫复旧方法的最新研究进展进行归纳总结,以期为研究动物产后子宫复旧的分子调控机制及研发促进子宫复旧新方法提供一定参考。  相似文献   

7.
The plasma hormone profile of progesterone, 17-oestradiol, prolactin, growth hormone (GH), cortisol, triiodothyronine (T3), thyroxine (T4) and insulin were estimated by radioimmunoassay in jugular blood samples from 10 Alpine×Beetal crossbred goats during the periparturient period. The plasma progesterone concentrations declined from day 20 prior to kidding to the day of kidding and then remained at a basal level. 17-Oestradiol concentrations declined from day 20 to day 4 prepartum, followed by a continuous increase to reach a peak at kidding. Plasma oestradiol declined abruptly on day 1 postpartum and remained low throughout the postpartum period. The plasma prolactin concentrations increased continuously from day 20 to day 10 prepartum but then increased to a peak on the day of kidding, followed by a transient decline by day 5 postpartum. The plasma GH concentrations varied significantly (p<0.01) on the different days of sampling but were highest on the day of kidding. The plasma cortisol concentration declined from day 20 to day 2 prepartum, after which it abruptly increased on day 1 prepartum to reach a peak on the day of kidding. The concentrations of plasma T3 remained similar during the prepartum period but were minimal on the day of kidding and increased during postpartum period. The concentration of plasma T4 was also lowest on the day of kidding and increased during the postpartum period. Plasma insulin concentrations were low in the day of kidding.  相似文献   

8.
Retained placenta, endometritis, cystic ovaries and low conception rates are often considered as interconnected conditions in cattle. Wide ranges in amounts of selenium and vitamin E supplements have been advised in late-pregnancy diets and, frequently, they can be synergistically beneficial. Animals at grass or with other green foods should be of adequate vitamin E status, but dietary selenium deficiencies are both more frequent and severe. Selenium status is important for superovulation in cattle and multiple births in ewes because of its importance in sperm transport and establishment of ova. However, the potential toxicity of selenium-enriched feed supplements restricts their use on a free-access basis. Giving sodium selenite or selenate by injection provides only a short-term response in the plasma. Barium selenate given in oil by injection provides a more durable response but has potential tissue residue problems. Compressed metallic selenium powder with iron powder in high-density reticulo-ruminal pellets gives sustained release, but uncertainties regarding possible surface coating and the variable effects of selenium particle size may require additional grinders to ensure prolonged release. Neither reticulo-ruminal pellets of such composition nor barium selenate by injection may be used worldwide because only sodium selenite and selenate have general regulatory approval. A sustained-release multi-trace element/vitamin rumen bolus system effective for several months has increased lambing percentages in ewes, and increased herd conception rates and reduced the spread of calving for herds of beef cattle.  相似文献   

9.
The aim of this study is to evaluate the influence of duration of calving and obstetric assistance on retained placenta incidence of high milk production Holstein cows. Experimental groups were determined according to the duration of the expulsive phase of calving: 2 h (n = 16), 2‐4 h (n = 16) and >4 h (n = 12), and additionally allocated in two sub‐groups: spontaneous calving (n = 22) and intervention calving (n = 22). Diagnosis of retained placenta was considered with a threshold of 8 h after the expulsive phase. Cows without obstetric intervention, with labor duration of 2 h, presented reduced time needed for placental release, in comparison to those with obstetric assistance. In the 2–4 h group and >4 h, there was no statistical difference. The 2 h and 2–4 h groups with intervention and the spontaneous >4 h group were considered retained placenta groups. On the other hand, performing obstetric intervention when calving period was superior to 4 h nulled the occurrence of retention of fetal membranes. As a conclusion, obstetric assistance predisposes placental retention to calving with <2 h of duration in dairy cows. Conversely, when calving is more than 4 h, performing fetal extraction has a beneficial influence on preventing retained placenta.  相似文献   

10.
奶牛子宫复旧的B-超影像学研究   总被引:3,自引:1,他引:2  
应用连续直肠检查法和B型实时超声断层扫描仪(B- 超)监测法,对38 头中国荷斯坦奶牛的子宫复旧过程和复旧规律进行研究。实验结果表明:经连续直肠检查法监测,受试牛子宫孕角、空角和子宫颈复旧的平均时间分别为(37.4±31) 、(314±49)和(36.8 ±49) d;用B- 超监测则为(35.5 ±4.5)、(30.8 ±5.9) 和(37 .5 ±5.0) d。并且B-超监测还发现,分娩当天子宫肌层平均厚度为1.65 cm ,产后第23 天时减少到1.35 cm ;产后第5 天在超声影像上可见子宫内膜,平均厚度为0.3cm ,第15 天为0 .6cm ,而到产后23 d 平均增厚到1.02cm ,子宫复旧完成时,子宫壁平均厚度为1.0 cm ;两子宫角的横切面轮廓清晰,大小基本相同,超声影像变白。  相似文献   

11.
The objectives of this study were to determine the effects of acupuncture in dairy cows (Bos taurus) on caruncular matrix metalloproteinase type‐2 (MMP2) at 0, 2 and 4 hr after calving. Acupuncture (n = 6) was applied at 0 and 2 hr after calving to 6 points that relax the cervix and stimulate uterine contractions. Controls (n = 9) were kept in a stanchion for 15 min without acupuncture. All of the cows in the study delivered their placenta in <4 hr. Formalin‐fixed caruncles were paraffin‐embedded and subjected to routine immunohistochemistry to determine MMP2 expression, which was scored by a single observer. Flash frozen caruncles were homogenized, and protein concentration was determined. MMP2 concentrations were calculated using commercial bovine ELISAs. MMP2 enzyme activity was determined using zymography. The mean value for each time point for each cow was used to calculate the mean ± SEM for each treatment group. MMP2 was predominantly localized to the epithelial and subepithelial stromal cells of the caruncles in both treatment groups. MMP2 immunoexpression was lower 4 hr after calving in the control cows (p = 0.012) but not in the acupuncture treated cows indicating that acupuncture treatment maintained MMP expression. MMP2 tissue concentration was lower 2 hr after calving in the control cows (p = 0.048) but not in the acupuncture treated cows. MMP2 enzyme activity decreased from 0 to 2 hr after calving in control cows (p = 0.046) but not in acupuncture treated cows. This study provides physiologic evidence for the effects of acupuncture on the bovine reproductive tract and substantiates the use of this treatment in cases of placental retention.  相似文献   

12.
13.
应用B型实时超声断层扫描仪 (B -超 ) ,对奶牛子宫复旧过程进行研究。对 38头中国荷斯坦奶牛 ,用B -超和连续检查法监测了子宫复旧过程。结果 ,经连续直肠检查法监测 ,受试牛子宫孕角、空角和子宫颈复旧的平均时间分别为 (37.4± 3.1)、(31.4± 4.9)和 (36 .8± 4.9)d;用B -超监测则为 (35 .5± 4.5 )、(30 .8± 5 .9)和 (37.5± 5 .0 )d。并且B -超监测还发现 ,分娩当天子宫肌层平均厚度为 1.6 5cm ,产后 2 3d时减少到 1.35cm ;产后第 5天在超声影像上可见子宫内膜 ,平均厚度为 0 .3cm ,第 15天为 0 .6cm ,而到产后 2 3d平均增厚到 1.0 2cm ,子宫复旧完成时 ,子宫壁平均厚度为1.0cm ;两子宫角的横切面轮廓清晰 ,大小基本相同 ,超声影像变白。研究表明B -超监测奶牛子宫复旧过程是可行的  相似文献   

14.
应用B型实时超声断层扫描仪(B- 超),对奶牛子宫复旧过程进行研究。对38 头中国荷斯坦奶牛,用B- 超和连续检查法监测了子宫复旧过程。结果,经连续直肠检查法监测,受试牛子宫孕角、空角和子宫颈复旧的平均时间分别为(37 .4±3.1)、(31.4 ±4.9)和(36.8 ±4.9) d;用B- 超监测则为(35 .5±4.5) 、(30.8 ±5.9)和(37.5 ±5.0)d。并且B-超监测还发现,分娩当天子宫肌层平均厚度为1.65 cm ,产后23 d 时减少到1.35cm ;产后第5 天在超声影像上可见子宫内膜,平均厚度为0 .3 cm ,第15 天为0 .6 cm ,而到产后23 d 平均增厚到1.02 cm ,子宫复旧完成时,子宫壁平均厚度为1 .0 cm ;两子宫角的横切面轮廓清晰,大小基本相同,超声影像变白。研究表明B- 超监测奶牛子宫复旧过程是可行的。  相似文献   

15.
16.
17.
Morphological changes to and collagen loss from the rat uterus during postpartum involution were investigated. The expression patterns of collagen type III and myeloperoxidase (MPO) were also determined. Morphological changes were studied on days 1, 3, 5, 10, 15, 20, 22 and 25 postpartum. As a control, diestrus rats’ uterine were used. Specimens from the uterine horn were embedded in paraffin, cut into 8 µm coronal sections, and stained with hematoxylin‐eosin. The thickness of the longitudinal and circular smooth muscle layers and of the endometrium were measured. The collagen content was determined using hydroxyproline analysis. Immunostaining was used to examine the expression of collagen type III on days 1, 3, 5, 10, 15 and 20 postpartum; and MPO on days 1, 3, 5, 10 and 22 postpartum. The thickness of the smooth muscle layers was found to decrease rapidly postpartum: the circular smooth muscle layer returned to that of a non‐pregnant, control uterus by day 5 postpartum and the longitudinal smooth muscle layer by day 15 postpartum. Eosinophilic cells were observed in the endometrial stroma adjacent to the myometrium on days 10, 15 and 20 postpartum, and were confirmed as collagenous cells. Immunostaining identified collagen type III positive cells in the vessel‐rich layer adjacent to the placental site on days 1, 3, 5 and 10 postpartum, and these cells were confirmed to be phagocytic. Postpartum reduction in the weight of the uterus was accompanied by decreases in both the collagen content and the thickness of the longitudinal and circular smooth muscle layers. Furthermore, the phagocytic cells were shown to express MPO during postpartum involution of the uterus.  相似文献   

18.
One hundred and six Holstein and Holstein x native cows were inspected before and after slaughter, and liver samples were taken. The fat content of all the liver samples was estimated by an extraction method (Soxhlet). The livers of 29 cows (27%) were classified as fatty. Seventeen of the animals were newly calved, 47 were non-pregnant, 33 were pregnant and 9 were dry, the median values for the fat content of their livers being 60.6, 34.4, 34.7 and 33.8 mg/g, respectively. The median concentration of liver fat in the first group was significantly different from that in each of the other groups (p < 0.01).  相似文献   

19.
围产期饲喂β-胡萝卜素对奶牛免疫性能的影响   总被引:5,自引:0,他引:5  
试验选择胎次相同、产奶量、体重和体况相近的中国荷斯坦奶牛36头,随机分为3组,分别饲喂对照日粮(基础日粮+150 000 IU维生素A),处理Ⅰ日粮(对照日粮+300 mg-β胡萝卜素),处理Ⅱ日粮(对照日粮+600 mg-β胡萝卜素),预试期15 d,试验期120 d。结果表明:添加-β胡萝卜素对奶牛血液白细胞数量和白细胞分类计数没有显著影响,但提高了围产期奶牛血液淋巴细胞的转化率(P<0.01)。-β胡萝卜素的添加提高了血浆中-β胡萝卜素和维生素A的浓度;在产后8-12周,处理组奶中-β胡萝卜素的浓度显著提高(P<0.005),而且奶中-β胡萝卜素的浓度随着-β胡萝卜素添加量的增加而上升,但-β胡萝卜素的添加对产后4周内奶中的-β胡萝卜素的浓度没有影响。  相似文献   

20.
为了探讨归芎益母散治疗奶牛血瘀型胎衣不下的作用,将40头血瘀型胎衣不下奶牛,随机分为4组,每组10头,分别为归芎益母散高、中、低剂量组(分别为800、400、200 g/头),以及药物对照组(250 g/头,益母生化散),经口灌服给药,每天1次,用药1 d~3 d。另选10头健康奶牛作为空白对照组。结果表明,与药物对照组(治愈率为70%)比较,高、中、低剂量组治愈率为90%、90%、50%(P>0.05),给药后第0天,与空白对照组比较,患病奶牛ET-1、TXB2显著升高(P<0.01,P<0.05),NO、6-keto-PGF显著降低(P<0.01),ET-1/NO、TXB_2/6-keto-PGF显著增大(P<0.01)。用药后第7、14、21天,与药物对照组相比,高、中剂量组ET-1、TXB_2水平降低,NO、6-keto-PGF水平升高,ET-1/NO、TXB_2/6-keto-PGF减小。说明归芎益母散能够通过对抗内皮功能紊乱和血小板功能紊乱,缓解患牛血瘀状态,从而改善子宫血液循环及微循环障碍,调节子宫节律性收缩,促进子宫内滞留胎衣排出,临床推荐使用剂量为400 g/头,经口灌服,每天1次,用药1 d~3 d。  相似文献   

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