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941.
Margalioth Ehud J.; Taney Frances H.; Cooper George W.; Scholl Gerald M.; Rosenfeld David L. 《Human reproduction (Oxford, England)》1993,8(5):752-754
The number of embryos transferred, ease of embryo transfer,and rate of embryo cleavage are significant factors affectingthe success of IVF. High levels of oestradiol occurring whenHCG is given may reduce implantation and pregnancy rates. Adiscrepancy between the stage of embryonic development and thephase of endometrial maturation at embryo transfer may be responsiblefor IVF failure in some cases. 相似文献
942.
We examined the localization of basic fibroblast growth factor (bFGF) in the developing embryonic and newborn rat nervous system using 2 anti-bFGF antibodies. Embryonic (E13, E14, E15, E16, E17, and E18) and newborn tissues were examined. Between E16 and E17 strong bFGF immunoreactivity (IR) was detectable in the cortex and striatum and, in addition, in almost all neurons of the brainstem, spinal cord, and spinal ganglia. In contrast, in the newborn rat bFGF-IR was found in neuronal subpopulations of brainstem nuclei, ventral spinal cord, and spinal ganglia as it is known for the respective postnatal/adult parts of the nervous system. At E16 7.0 kb and 3.7 kb bFGF mRNA were present. The identification of bFGF-responsive cells was performed using immunocytochemistry (anti-flg antibody) and 125I bFGF for binding studies. The neuronal localization of FGF-receptor suggests that bFGF mediates its effects in an autocrine or paracrine manner. At the time of strongest bFGF-staining (E16/17), proliferation of neurons is almost completed in most of the nervous system areas. Therefore, it could also be suggested from previous biological experiments that the physiological functions of bFGF could include trophic and/or differentiating effects on developing neurons rather than mitogenic effects. The change of the bFGF-staining pattern after birth could indicate a change in the physiological function of bFGF, i.e., different bFGF effects in the immature and mature nervous systems. © 1993 Wiley-Liss, Inc. 相似文献
943.
转化生长因子α对A系小鼠胚腭突细胞增殖代谢的影响 总被引:1,自引:0,他引:1
目的 研究不同剂量转化生长因子α(TGFα)对A系小鼠胚腭突细胞增殖和DNA、蛋白质及PGE2合成的影响。方法 实验分为 9组 ,每组设平行 4孔 (瓶 ) ,分别加入TGFα使其终浓度为 0 .0 0 5ng/ml,0 .0 1ng/ml,0 .0 5ng/ml,0 .1ng/ml,0 .5ng/ml,1ng/ml,5ng/ml,10ng/ml,5 0ng/ml。每组均设空白对照。在实验后第 1、3、5天分别检测细胞的OD值、DNA、蛋白质和PGE2 的含量。结果 TGFα可显著增加腭突细胞的OD值 ,促进DNA及蛋白质合成 ,在培养早期TGFα促进腭突细胞PGE2 的合成 ,而在培养后期则表现为抑制作用。在含量 0 .0 0 5~ 10ng/ml,TGFα促细胞增殖作用呈剂量依赖性 ,10ng/ml时TGFα的作用最强。 结论 TGFα显著促进腭突细胞的增殖代谢 ,其作用与表皮生长因子 (EGF)相类似 ,可能与EGF及其他生长因子共同调节腭发育。 相似文献
944.
945.
体外定向诱导人胚胎干细胞分化为表皮样干细胞的研究 总被引:10,自引:2,他引:8
[目的]探索体外定向诱导人胚胎干细胞(hES细胞)分化为表皮样干细胞的条件,为研究其定向分化机理及寻找新的皮肤组织工程种子细胞奠定基础。[方法]将人胚胎干细胞单独(对照组)或与人羊膜上皮面向上全铺或半铺布半孔底共培养4~5 d,观察其形态变化并分别用β1整合素,CK15及CK19免疫组化检测人胚胎干细胞向表皮样干细胞的分化。[结果]人胚胎干细胞与人羊膜共培养4~5 d后,在人羊膜上皮面形成表皮样干细胞集落,表达高水平的表皮干细胞特异标记物β1整合素、CK15和CK19。在无羊膜覆盖处,细胞贴壁生长,形成单层表皮样细胞,细胞呈多边形,排列紧密,大部分细胞表达β1整合素。对照组大量细胞死亡,未见β1整合素阳性细胞。[结论]在体外人羊膜可定向诱导人胚胎干细胞分化为表皮样干细胞,并提示在羊膜上皮面的细胞克隆可能是表皮样干细胞,而贴壁生长的细胞可能大部分是表皮样瞬间放大细胞。 相似文献
946.
目的 探讨以Buffalo大鼠肝细胞培养上清(BRL-CM)替代含LIF培养液体外培养小鼠胚胎干细胞(ESC)的可行性;无血清体外诱导ESC为神经前体细胞(NPC)。方法 以BRL-CM维持ESC生长并抑制其分化,用含LIF的培养液作为对照,硝基四氮唑蓝/5-溴-4氯-3-吲哚基磷酸(NBT/BCIP)显色检测碱性磷酸酶。采用N2选择性无血清培养法获取NPC,免疫组化法检测巢蛋白(Nestin)鉴定。结果 BRL-CM与含LIP的培养液一样能维持ESC未分化状态,无血清培养基诱导。ESC后获得细胞的86%为NPC。结论 BRL-CM可替代LIF用于ESC培养,且经济、简便。采用N2选择性培养基可获得较高纯度的NPC。 相似文献
947.
牛磺酸对大鼠胚胎期海马发育的影响 总被引:1,自引:0,他引:1
目的:探讨牛磺酸对大鼠胚胎期海马发育的影响.方法:大鼠自受孕开始喂以实验饲料,分为对照组和0.6%牛磺酸组.观察新生仔鼠海马中蛋白质、DNA和RNA的含量及海马超微结构的变化.结果:0.6%牛磺酸组新生仔鼠海马蛋白质、DNA和RNA的含量显著高于对照组(P<0.01).电镜下见0.6%牛磺酸组新生仔鼠海马神经元核仁明显,有丰富的粗面内质网、核糖体和线粒体等细胞器,线粒体嵴清晰可见.结论:母体在妊娠期间补充牛磺酸,有利于仔鼠海马的发育. 相似文献
948.
Nancy L. Nadon Shirley Miller Karen Draeger Michelle Salvaggio 《International journal of developmental neuroscience》1997,15(3):1298
DM20 is a proteolipid protein that has been extensively studied for its role in central nervous system myelination. We demonstrate that DM20 expression is wide-spread and independent of myelination. In the Schwann cells and neurons of the peripheral nervous system, DM20 is not incorporated into the membrane as it is in the central nervous system (CNS) , but remains cytoplasmic. Mutations that severely reduce the amount of DM20 mRNA in CNS myelinating cells have little effect on DM20 expression in nonmyelinating cells of the peripheral nervous system and embryonic CNS. Most importantly, the combination of wild-type DM20 from the endogenous X-linked gene and mutant DM20 expressed from an autosomal transgene results in embryonic lethality. We propose a function for DM20 to explain these diverse findings based on the ability of DM20 to form multimeric complexes, and hypothesize that the DM20 complex participates in intracellular molecular transport. 相似文献
949.
Fisher M. International Journal of Nursing Practice 1997; 3: 188–190
The specialist learning disability nurse in Wales
This paper reflects on the development of services for people with learning disabilities within the United Kingdom and focuses on the role of the specialist nurse. The nurse's contribution to the care of this client group has been the subject of debate and controversy for a number of years. Developments within the learning disability field in Wales in particular are explored, with the All Wales Strategy for People with Learning Disabilities providing the background and context for these developments. An example of how specialist nurses from around Wales came together in order to share good and best practice is discussed. The conclusion is that the specialist learning disability nurse has a great deal to offer, but must be prepared to work together with other professionals as well as service users and their families. 相似文献
The specialist learning disability nurse in Wales
This paper reflects on the development of services for people with learning disabilities within the United Kingdom and focuses on the role of the specialist nurse. The nurse's contribution to the care of this client group has been the subject of debate and controversy for a number of years. Developments within the learning disability field in Wales in particular are explored, with the All Wales Strategy for People with Learning Disabilities providing the background and context for these developments. An example of how specialist nurses from around Wales came together in order to share good and best practice is discussed. The conclusion is that the specialist learning disability nurse has a great deal to offer, but must be prepared to work together with other professionals as well as service users and their families. 相似文献
950.
S. I. Kolesnikov Yu. V. Gladyshev L. N. Demidova N. G. Gladysheva S. V. Alisievich 《Bulletin of experimental biology and medicine》1997,123(5):509-512
After 2 days of aseptic inflammation in pregnant rats the number of hematopoietic lineage cells in the embryonic liver decreased,
while proliferative activity of cells in the embryonic lung increased. Degenerative changes were noted in the placenta.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 5, pp. 584–587, May, 1997 相似文献