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371.
Cell–cell interactions among cell types constituting the fetal liver such as hepatoblasts, stellate cells and endothelial
cells lead to functional lobule development. The present study was undertaken to investigate hepatic histogenesis in the primary
culture of E12.5 mouse livers, including cell–cell and cell–matrix interactions. Fetal livers were dispersed with protease
treatment and cultured for 5 days. Cellular adhesion of each hepatic cell type, gene expression and extracellular matrix deposition
were analyzed by immunohistochemistry and immunoblotting. Immunohistochemical analysis demonstrated that the primary culture
of fetal liver cells contained at least hepatoblasts, mesenchymal cells, endothelial cells, hemopoietic cells and Kupffer
cells. Although hepatoblasts, mesenchymal cells, and endothelial cells aggregated separately in the initial step, they then
formed a spheroid together, adhering to the glass slide, which led to the formation of flattened hepatic organoids. Hepatoblasts
more preferentially adhered to mesenchymal cells than endothelial cells. Several extracellular matrix depositions were seen
in aggregates consisting of at least hepatoblasts and mesenchymal cells within 12 h, but were poor in those lacking hepatoblasts.
These data show that the primary culture of fetal liver cells contains most cell types constituting fetal livers, and may
be useful for studying cell–cell interactions during liver development. 相似文献
372.
The use of continuous fetal heart rate (FHR) and uterine pressure monitoring in the chimpanzee (Pan troglodytes) by external Doppler transducer and tocodynamometer is described in 1) the routine obstetrical assessment of fetal well-being, 2) oxytocin challenge (stress) testing (OCT) and non-stress testing (NST) for the diagnosis of in utero fetal distress, and 3) induction of labor by intravenous oxytocin infusion, by surgical rupture of the chorio-amniotic membranes (amniotomy), or by a combination of these techniques, as an alternative to Caesarean section for clinical, managemental, or experimental purposes. FHR traces were analyzed during a total of 57 term pregnancies for three basic characteristics: baseline rate, variability, and periodic pattern. Results indicated that continuous FHR monitoring in the chimpanzee can provide a valuable tool for fetal assessment and management of labor in any attempt to reduce the unacceptably high annual incidence of perinatal and neonatal infant mortality reported in the U.S. 相似文献
373.
胰岛素样生长因子与哺乳动物的胚胎发育 总被引:15,自引:0,他引:15
综述了胰岛素样生长因子(IGFs)在胚胎发育过程中的表达特点和对胚胎发育的作用。许多研究表明,IGFs、IGF受体、IGF结合蛋白(IGFBPs)在不同发育阶段的胚胎中具有不同的表达特点,并具有组织特异性。不论是母体来源的、胎儿自身产生的、还是外源性的IGFs都能促进细胞分化和增殖,对胚胎发育有重要作用。 相似文献
374.
A new cell culture supplement, platelet lysate, was evaluated with reference to fetal bovine serum (FBS), an established industrial
medium for animal cell culture. Chemical and bacteriological profiles were conducted including the presence of platelet-derived
growth factor (PDGF). PDGF was detected in the platelet lysate but it was not present in FBS. The platelet lysate medium demonstrated
lack of microorganisms, mycoplasma and endotoxins. The platelet lysate was investigated in culture studies (cell growth, viability
and product formation) towards a number of target cells including myelomas, hybridomas, hepatocytes, fibroblasts and epithelial
cells. In general the platelet lysate medium supported cell growth and maintained viabilities comparable or superior to fetal
bovine serum. Productivity studies of antibodies (hybridomas) and transferrin (hepatocytes) showed similar or enhanced production
in platelet-derived medium in comparison with FBS.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
375.
Reuvit Halperin Eran Hadas Nili Shinnar Ian Bukovsky David Schneider 《Journal of Experimental Animal Science》2003,42(3):171-176
We intended to use the rat model to study the effect of autoantibodies on implantation and fetal viability. However, we have since found an effect of normal rat serum on fetal resorption rate and fetal viability. The objective of this study was to determine the consistency of this effect. Wistar strain albino rats were used for injection of 150 μl normal rat serum into the lumen of uterine horn on days L2–L6. The other uterine horn, used as a control, was injected with 150 μl normal saline. Percent implantation, fetal resorption rate and fetal viability were determined following the intrauterine injection of normal rat serum as compared with normal saline. A significant increase in fetal resorption rate was observed following the injection of rat serum on days L4 and L5 (P = 0.003 and P = 0.001, respectively). A significant decrease in fetal viability was demonstrated following the injection of rat serum on day L5 (P = 0.01). The rat can provide a suitable animal model for further studies. 相似文献
376.
Ethanol-induced damage in the developing brain may result in cognitive impairment including deficits on neuropsychological tests of learning, memory and executive function, yet the underlying mechanisms remain elusive. In the present study we investigated the protective effect of tocotrienol against cognitive deficit, neuroinflammation and neuronal apoptosis in rat pups postnatally exposed to ethanol. Pups were administered ethanol (5g/kg, 12% v/v) by intragastric intubation on postnatal days 7, 8 and 9. Ethanol-exposed pups showed significant memory impairment in Morris water maze task as evident from increase in escape latency and total distance travelled to reach the hidden platform. Time spent in target quadrant, % total distance traversed in target quadrant and frequency of appearance in target quadrant was also significantly decreased in ethanol exposed pups in probe trial. Poor memory retention was exhibited by ethanol-exposed pups in elevated plus maze test also. Impaired cognition was associated with significantly enhanced acetylcholinesterase activity, increased neuroinflammation (oxidative-nitrosative stress, TNF-α, IL-1β and TGF-β1) and neuronal apoptosis (NF-κβ and Caspase-3) in different brain regions of ethanol-exposed pups. Co-administration with tocotrienol significantly ameliorated all the behavioral, biochemical and molecular alterations in the different brain regions of ethanol exposed pups. The current study thus demonstrates the possible involvement of NF-κβ mediated apoptotic signaling in cognitive deficits associated with postnatal ethanol exposure in rats and points to the potential of tocotrienol in the prevention of cognitive deficits in children with fetal alcohol spectrum disorders (FASDs). 相似文献
377.
母体外周血中分离的胎儿有核红细胞(fNRBCs)包含胎儿完整的遗传信息,可用于无创产前诊断。fNRBCs的分离和富集方法主要分为三类:物理分选法、抗原-抗体结合分离法和增殖法。不同的方法获得的fNRBCs的数量和纯度不同,多种方法联合使用可以提高富集产物中fNRBCs的纯度和数量。本文就母体外周血中fNRBCs的分离和富集方法进行综述。 相似文献
378.
马传染性贫血病毒弱毒株感染驴胎皮肤细胞(FDD)的前病毒DNA整合动态 总被引:4,自引:0,他引:4
马传染性贫血病毒弱毒株,经驴胎皮肤细胞培养,斑点杂交及PCR检测,在感染后2-10天的细胞染色体中的检出前病毒DNA,证明EIAV弱毒株对感染细胞具有整合作用,在感染后第6天,整合的前病毒的量达到高峰,其含量与病毒的致细胞病变作用相对应。前病毒的存在形式为整合形式,未检出非整合形式的前病毒,在健康的FDD细胞中未检出的前病毒,说明EIAV属于外源性病毒。 相似文献
379.
MCF7 cells were cultured with steroids, labelled with (35S)-methionine and the secreted and intracellular proteins were examined by one and two dimensional gel electrophoresis. Estradiol (0.1 nM) increased the synthesis of some of the secreted proteins; the induction of a protein of molecular weight 46,000 daltons being the most dramatic. The 46,000 daltons secreted protein was heterogeneous with respect to molecular weight and isoelectric point. The antiestrogen Tamoxifen did not stimulate the synthesis of any of the estrogen induced proteins, but completely inhibited the induction by estradiol. The effect of estradiol on internal proteins was much more subtle; only 3 proteins out of about 250 were stimulated. The functions of these Proteins are unknown, however they appear to be good markers for studying the mechanism of action of estrogens and antiestrogens in breast cancer and might be related to the control of cell proliferation by estrogen. 相似文献
380.