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991.
目的 从胎盘组织中分离获得人胎盘源间充质干细胞(PMSCs).并诱导其向成骨细胞和脂肪细胞分化,为PMSCs应用于组织工程和细胞治疗提供实验依据.方法 将人胎盘组织经胶原酶消化、贴壁和传代培养获得PMSCs,流式细胞仪检测其表面标志,分别联合应用β-甘油磷酸钠、维生素C、地塞米松体系和3-异丁基-1-甲基黄嘌呤、胰岛素、吲哚美辛、地塞米松体系将其诱导分化为成骨细胞和脂肪细胞,继而采用碱性磷酸酶检测和Von kossa染色对其进行成骨分化鉴定,采用油红O染色对其进行脂肪分化鉴定.结果 从人胎盘中成功分离获得了PMSCs,形态呈纤维状,细胞增殖能力强;流式细胞仪分析显示PMSCs表达CD29、CD44、CD105、CD106和CD166,不表达CD34、CD45、HLA-DR:人PMSCs经成骨诱导2周后,碱性磷酸酶染色呈强阳性,Von kossa染色可见明显钙结节;人PMSCs经成脂诱导3周后,油红O染色呈阳性,有明显的脂滴出现.结论 建立了有效分离、培养人PMSCs的实验体系,并能使其在体外诱导向成骨细胞和脂肪细胞分化,表明PMSCs可作为新型来源的种子细胞应用于组织工程. 相似文献
992.
植入性胎盘这一病症,随着近些年来人工流产、引产、和刮宫等宫腔操作的增多,其发病率越来越高,对产妇危害越来越大。因此,有必要引起广大妇产科工作者对此病症的重视。笔者认为,探讨此病可从对此病的认识、病因、诊断和处理四个方面入手,特别是对此病的诊断和处理治疗,是本文的重点。 相似文献
993.
994.
427例前置胎盘高危因素分析 总被引:6,自引:1,他引:5
目的 探讨前置胎盘发病的高危因素.方法 回顾性分析本院2002年1月至2008年6月分娩的427例前置胎盘病例(病例组)和2135例随机抽取的单胎产妇作对照(对照组)的临床资料.结果 前置胎盘的发病率为1.16%(427/36 669).前置胎盘组产妇年龄大于对照组,年龄大于或等于30岁,尤其大于或等于35岁时前置胎盘的发病率明显增高(OR:2.3~2.6;95%CI:1.6~3.8),流产次数大于或等于3(OR:2.0~3.2;95%CI:1.3~6.8),产次大于或等于2(OR:1.4~3.2;95%CI:1.2~5.7),前次剖宫产(OR:1.6~2.8;95%CI:1.6~6.1)均是前置胎盘的高危因素.此外,早产(OR:4.6;95%CI:3.8~6.1)、先天性子宫畸形(OR:5.6;95%CI:3.3~7.5)及既往有前置胎盘史(OR:6.2;95%CI:3.6~8.2),也与前置胎盘密切相关.结论 孕妇年龄大于或等于35岁、流产次数大于或等于3次、产次大于或等于3、前次剖宫产、有早产史、先天性子宫畸形患者是前置胎盘发病的高危因素. 相似文献
995.
The novel inflammatory cytokine high mobility group box protein 1 (HMGB1) is expressed by human term placenta 总被引:1,自引:0,他引:1
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Holmlund U Wähämaa H Bachmayer N Bremme K Sverremark-Ekström E Palmblad K 《Immunology》2007,122(3):430-437
High mobility group box protein 1 (HMGB1) was previously considered a strict nuclear protein, but lately data are accumulating on its extranuclear functions. In addition to its potent proinflammatory capacities, HMGB1 has a prominent role in a number of processes of specific interest for the placenta. Our overall aim was to investigate the expression of HMGB1 in human term placenta and elucidate a potential difference in HMGB1 expression comparing vaginal deliveries with elective Caesarean sections. In addition, placentas from normal pregnancies were compared with placentas from pregnancies complicated by pre-eclampsia. Twenty-five placentas, 12 from normal term pregnancies and 13 from pregnancies complicated by pre-eclampsia were analysed with immunohistochemistry for HMGB1 and its putative receptors; receptor for advanced glycation end-products (RAGE), Toll-like receptor 2 (TLR2) and TLR4. We present the novel finding that in addition to a strong nuclear HMGB1 expression in almost all cells in investigated placentas, an individual variation of cytoplasmic HMGB1 expression was detected in the syncytiotrophoblast covering the peripheral chorionic villi, by cells in the decidua and in amnion. Production of HMGB1 was confirmed by in situ hybridization. Although labour can be described as a controlled inflammatory-like process no differences in HMGB1 expression could be observed comparing active labour and elective Caesarean sections. However, a tendency towards a higher expression of cytoplasmic HMGB1 in the decidua from women with pre-eclampsia was demonstrated. The abundant expression of the receptors RAGE, TLR2 and TLR4 implicates a local capability to respond to HMGB1, although the precise role in the placenta remains to be elucidated. 相似文献
996.
Endometrial stromal nodule embedded into term placenta 总被引:1,自引:0,他引:1
Karpf EF Poetsch B Langner C Nogales FF Regauer S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2007,115(11):1302-1305
A 28-year-old patient presented with a 5 cm endometrial stromal tumor situated at the uteroplacental interface, which was diagnosed ultrasonographically at the 28th week of pregnancy. The tumor was asymptomatic and closely attached to the decidua; after a normal term delivery, it was revealed to be embedded within the placenta. Microscopically, the neoplasm had a high mitotic rate and characteristic features of endometrial stromal tumor, such as CD10, progesterone receptor positivity, and an expansile linear, non-infiltrative pushing border. There were also pregnancy-related changes such as decidualization and myxoid change. In conclusion, the lesion was considered a benign endometrial stromal nodule with an unusual morphology and increased proliferation rate due to the hormonal stimuli of pregnancy. 相似文献
997.
目的探讨剖宫产史次数对中期妊娠胎盘前置状态伴植入经阴道引产结局的影响。方法回顾性分析上海交通大学医学院附属国际和平妇幼保健院2008年6月—2020年10月具有剖宫产史的中期妊娠胎盘前置状态伴植入经阴道引产的49例患者临床资料,根据剖宫产史次数分为2组: 1次剖宫产史患者,共33例;≥2次剖宫产史患者,共16例。探讨比较2组患者的引产结局。结果剖宫产史≥2次的患者较1次剖宫产史的患者住院时间长、住院费用高、引产出血量多,且失血性休克、弥散性血管内凝血(disseminated intravascular coagulation, DIC)、感染和子宫切除发生率均较高(P<0.05)。4例经阴道引产失败后子宫切除者均为具有2次剖宫产史的中央性胎盘前置状态植入型或穿透型患者。结论剖宫产后中期妊娠胎盘前置状态伴植入经阴道引产的结局与剖宫产次数有关。剖宫产史≥2次的患者较1次剖宫产史的患者更容易发生产后大出血、DIC、感染或子宫切除等不良结局。 相似文献
998.
人胎盘与脐动、静脉血造血干/祖细胞归巢相关黏附分子表达的研究 总被引:3,自引:0,他引:3
为了评价人胎盘组织造血干/祖细胞(hematopoieticstem/progenitorcell,HSPC)的归巢能力,采用机械法制备人胎盘组织单个细胞悬液,用流式细胞术分析胎盘组织及脐动、静脉血有核细胞中CD34+细胞及其亚群的含量,检测三者来源的CD34+细胞表面归巢相关黏附分子CD44、CD11a、CD62L、CD49d、CD49e和CD54的表达水平。结果显示,胎盘组织CD34+细胞及CD34+CD38-细胞百分率明显高于脐动、静脉血;脐动脉与脐静脉血中HSPC百分率没有明显差异。胎盘来源CD34+细胞高度表达黏附分子CD11a、CD49d、CD44、CD49e及CD54,其中表达CD49e及CD54水平明显高于脐动、静脉血CD34+细胞。胎盘来源的CD34+CD62L+细胞百分率为(64.58±15.52)%,低于脐静脉血来源的表达。结论:人胎盘富含HSPC。胎盘来源的CD34+细胞多数黏附分子的表达水平近似或高于脐血,提示胎盘HSPC的归巢能力有可能强于脐带血。 相似文献
999.
A small-angled thin edge of the placenta predicts abnormal placentation at delivery. 总被引:1,自引:0,他引:1
Ken-ichi Shukunami Koji Nishijima Tetsuji Kurokawa Kimihisa Tajima Naoyuki Kamitani Yoshio Yoshida Fumikazu Kotsuji 《Journal of ultrasound in medicine》2005,24(3):331-335
OBJECTIVE: This study was intended to determine the relationship between the angle of the lower placental edge in early pregnancy and the previa/low-lying placenta at delivery. METHODS: We used transvaginal sonography to consecutively screen 2543 singleton pregnancies. All subjects were scanned during the period of gestation between 12 weeks 0 days and 15 weeks 6 days. The angle of the lower placental edge was measured when the placenta covered the internal cervical os. These cases were followed sonographically until term. RESULTS: Of 168 cases in which the internal cervical os was covered at screening, 9 showed previa/low-lying placenta at delivery (previa/low-lying group). The remaining 159 showed no abnormal placentation (nonprevia group). There were significantly fewer degrees of angle in the previa/low-lying group than in the nonprevia group (P < .05). For the previa/low-lying group, the arithmetic mean, median, and SD values of the angles were 60.8 degrees , 50.0 degrees , and 9.8 degrees , respectively. For the nonprevia group, those values were 103.4 degrees , 103.0 degrees , and 31.8 degrees , respectively. Data based on the cutoff number of the angle of 74 degrees indicated the following: sensitivity of placenta previa or low-lying placenta at term, 100% (9 of 9); false-positive rate, 23% (36 of 159); positive predictive value, 20% (9 of 45); and negative predictive value, 100% (123 of 123). CONCLUSIONS: The angle between the placental-uterine interface and fetal placental surface can be evaluated during early pregnancy. It appears to accurately predict placenta previa or low-lying placenta at term gestation with a sensitivity of 100%, a false-positive rate of 23%, and a high negative predictive value of 100%, which would allow for elimination of some of the multiple scans. 相似文献
1000.