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81.
The emerging role of immunoregulation of fibrinogen-related procoagulant Fgl2 in the success or spontaneous abortion of early pregnancy in mice and humans. 总被引:12,自引:0,他引:12
D A Clark J W Ding G Chaouat C B Coulam C August G A Levy 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,42(1):37-43
PROBLEM: Abortion of chromosomally normal embryos in the CBA X DBA/2 mating combination is triggered by release of Th1 cytokines (tumor necrosis factor [TNF]-alpha, interferon [IFN]-gamma, and interleukin [IL]-1), which cause abortion via a novel prothrombinase, Fgl2, and polymorphonuclear leukocytes. The site of activation may be maternal vascular endothelium on arteries and veins nourishing the placenta. Activation of coagulation is also prominent in spontaneous abortion of chromosomally normal human embryos. We asked where is Fgl2 up-regulated in the uterus in murine abortions, and if similar Fgl2 expression occurs in human pregnancy failure. METHODS: Control CBA X DBA/2 pregnant mice, or from mice injected with TNF-alpha + IFN-gamma on day 7.5 of gestation, were removed on day 8.5, fixed, sectioned, and subject to in situ hybridization for Fgl2. Sections were also stained for fibrin. Elective first trimester termination samples or biopsies taken early in the course of a recurrent miscarriage were similarly fixed, sectioned, and analyzed by in situ hybridization. Control and cytokine-treated mice were anticoagulated with heparin, an activator of antithrombin III, and/or the direct anti-thrombin inhibitor hirudin. RESULTS: Low level Fgl2 expression localized to basal decidua remote from the embryo was noted in control mice; cytokine treatment, which causes greater than 80% of abortions, produced a striking up-regulation in this area as well as in a band at the junction of decidua and myometrium. Trophoblast also became strikingly positive. Fgl2 expression was associated with increased fibrin staining. Anticoagulation significantly protected against abortions, but doses were limited by the complication of retroplacental hemorrhage. In tissue from normal first trimester pregnancy, minimal Fgl2 positivity was seen in some villous syncytiotrophoblast, in villous stroma, cytotrophoblast, and in some cells in decidua. In spontaneous abortion of normal embryo, striking Fgl2 positivity was seen in syncytiotrophoblast and extravillous cytotrophoblast, in association with areas of thrombus formation. CONCLUSIONS: Fgl2 appears to be physiologically expressed and may protect against the internal danger of maternal and/or fetal bleeding during pregnancy and at parturition; a role in inhibiting transplacental traffic is also possible. External dangers in the form of stress, endotoxin, and antigens eliciting Th1 cytokine responses upregulate Fgl2 prothrombinase in trophoblast as well as in decidua, which results in spontaneous abortion of immunogenetically "weaker" embryos. 相似文献
82.
目的 探讨肠腔静脉C型分流术治疗食管胃底静脉曲张破裂出血的远期疗效。方法 对成阳市中心医院肝胆外科1992年以来施行的36例肠腔静脉C型分流术的临床资料进行总结分析。结果 36例患者术后门静脉压平均下降1.51kPa,胃镜检查食管静脉曲张均有明显减轻或消失。术后再出血率5.6%,肝性脑病发生率8_3%,术后1年、3年、5年及10年的生存率分别为97.2%、93.3%、89.3%及66.7%。结论肠腔静脉C型分流术手术适应证广,操作简单,近、远期疗效满意,适于推广。 相似文献
83.
Fiala C Aronsson A Granath F Stephansson O Seyberth HW Watzer B Gemzell-Danielsson K 《Human reproduction (Oxford, England)》2005,20(12):3414-3418
BACKGROUND: The pharmacokinetics of a novel slow-release (SR) misoprostol was studied and compared to conventional misoprostol. METHODS: Thirty-one women, pregnant between 8 and 12 weeks, requesting surgical abortion were randomly allocated to receive orally 400 microg conventional misoprostol, 400 microg SR misoprostol or 800 microg SR misoprostol. Venous blood samples were taken at 0, 30, 60, 120, 240 and 360 min after the administration of misoprostol. Misoprostol acid (MPA) was determined in serum samples using liquid chromatography/tandem mass spectrometry. RESULTS: Serum peak concentration (Cmax) was highest for conventional oral misoprostol. The time to peak concentration (Tmax) was similar for all groups. The area under the curve up to 360 min was similar for conventional and for 800 microg SR misoprostol and significantly greater for these groups compared to 400 microg SR misoprostol (P = 0.013). CONCLUSION: The new SR form of misoprostol demonstrated lower peak levels but longer-lasting elevation in plasma levels compared to conventional oral misoprostol. The AUC for 800 microg SR misoprostol was similar to that of 400 microg of conventional oral misoprostol. SR misoprostol may offer an alternative to repeated administration of oral misoprostol or to vaginal administration. 相似文献
84.
High NK cell activity in early pregnancy correlates with subsequent abortion with normal chromosomes in women with recurrent abortion 总被引:12,自引:0,他引:12
Yamada H Kato EH Kobashi G Ebina Y Shimada S Morikawa M Sakuragi N Fujimoto S 《American journal of reproductive immunology (New York, N.Y. : 1989)》2001,46(2):132-136
PROBLEM: The aim of this study was to assess the role of natural killer (NK) cells in pregnant women with a history of recurrent spontaneous abortion (RSA). METHOD OF STUDY: Consecutive 66 pregnant women with a history of RSA were prospectively assessed for peripheral NK cell activity, percentage of the NK cell subsets, and subsequent pregnancy outcome. RESULTS: NK cell activity in women with subsequent live birth (group I) at 4-5 gestational weeks (GW) (mean +/- SD, 32.5 +/- 12.31%) significantly decreased at 6-7 GW (28.1 +/- 12.1%) and at 8 9 GW (28.0 +/- 11.8%). NK cell activity in women with subsequent abortion with normal chromosomes (group II) at 6 7 GW (41.2 +/- 19.0%) was significantly higher than that in group I women, while NK cell activity at 6-7 GW in women with subsequent abortion with abnormal chromosomes (group III) was the same as the level in group I women. CONCLUSIONS: High NK cell activity at 6-7 GW correlates with subsequent abortion with normal chromosomes. 相似文献
85.
J Sj?berg 《Human reproduction (Oxford, England)》1987,2(7):615-616
Serum concentrations of pregnancy-associated plasma protein A (PAPP-A) were measured in patients with pregnancy-related gynaecologic emergencies including ectopic pregnancy (n = 124) and intrauterine abortion (n = 40). The results were compared with those in normal pregnancy (n = 136) and non-pregnant women (n = 460). In ectopic pregnancy and intrauterine abortion, the PAPP-A levels were lower than in normal pregnancy. In patients with a pregnancy-related gynaecologic emergency PAPP-A was undetectable in 82% of the ectopic pregnancies and in 55% of the intrauterine abortions. Considering the frequency of ectopic pregnancy (35.8%) and intrauterine abortion (52.3%) among all patients with pregnancy-related disorders, the likelihood that a pregnant patient with undectable PAPP-A has an ectopic pregnancy is 30%, and intrauterine abortion is 29%. These results indicate that although PAPP-A levels in ectopic pregnancy and intrauterine abortion are lower than in normal pregnancy, PAPP-A measurement cannot be used to distinguish between ectopic pregnancy and intrauterine abortion. 相似文献
86.
叶轮泵式全人工心脏的结构设计及流体力学特性 总被引:1,自引:1,他引:1
目的通过模型样机研制和流体力学特性测试.探索以叶轮式血泵为结构基础的新型可完全植入的全人工心脏。方法全人工心脏模型样机分为左心泵和右心泵2个基本单位。2血泵均采用叶轮泵.共同设置在球形外壳中。2半球形外壳由高分子材料经激光快速成型制成.球形腔内设置固定左右心泵后对合为球形外壳.表面由医用聚氨酯橡胶涂层,直径55mm,总质量150g左右。在体外模拟循环台上对左心泵和右心泵的流体力学特性进行测试.主要观测指标为泵的转速、输出压力、流量、能耗和效率。模拟循环装置由模拟左右心房、血泵、阻力调节器、流量计串联组成,采用30%甘油水溶液作为循环介质。通过调节阻力测定特定泵转速下压力和流量。结果体外模拟测试表明全人工心脏模型样机可满足血液动力学基本要求,左心泵在9000-13000r/min转速条件下可以达到5-7L/min流量和13.3kPa(100mmHg)的压力输出,右心泵在约1/2左心泵转速和4.00kPa(30mmHg)后负荷下达到相似流量.可分别满足体、肺循环的要求。在该工作负荷条件下,2血泵的总效率约为14%。结论轴流泵作为人工心脏的血泵单位.流体力学特性可达到全人工心脏的基本要求. 相似文献
87.
目的探讨一氧化氮合酶3(nitric oxide synthase 3,NOS3)基因第4内含子27bp数目可变串联重复序列(variable number of tandem repeat,VNTR)多态性和第7外显子894(G/T)多态性与复发性早期自然流产(recurrent early spontaneous abortion,RESA)的相关性。方法选取140例RESA患者和140名健康妇女,应用聚合酶链反应-琼脂糖凝胶电泳法检测NOS3基因第4内含子VNTR多态性,聚合酶链反应-限制性片段长度多态性分析技术检测第7外显子894(G/T)多态性。结果RESA组aa ba基因型频率和a等位基因频率与正常对照组相比差异有统计学意义(χ2=4.51,P<0.05;χ2=4.29,P<0.05)。与bb基因型相比,携带a等位基因的妇女与RESA显著相关(OR为1.8,95%CI:1.04~3.24)。RESA组TT GT基因型频率和T等位基因频率与正常对照组相比差异无统计学意义(χ2=1.16,P>0.05;χ2=1.12,P>0.05)。与GG基因型相比,携带T等位基因的妇女与RESA无相关。结论NOS3基因第4内含子27bp数目可变的串联重复序列多态性与复发性自然流产密切相关,NOS3基因第7外显子894G/T多态性与RESA无明显相关性,a等位基因是RESA重要的遗传易感基因。 相似文献
88.
苏爱 《中国优生与遗传杂志》2004,12(3):43-44
目的与方法本文对189例自然流产、闭经、发育不全患者进行细胞遗传学检查,结果发现异常核型16例,异常核型涉及1、3、4、5、6、7、8、9、10、 15、X、Y染色体.其中平衡易位10例,性染色体异常3例,大Y染色体3例.结论染色体异常是导致流产、闭经、性发育异常的重要遗传因素,应引起临床医师的高度重视. 相似文献
89.
Martin Griebe Michael Daffertshofer Mark Stroick Magdalena Syren Parviz Ahmad-Nejad Michael Neumaier Juergen Backhaus Michael G. Hennerici Marc Fatar 《Neuroscience letters》2007
Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool. 相似文献
90.
宫腔内人工授精97个周期临床分析 总被引:5,自引:0,他引:5
李岩 《中国优生与遗传杂志》2003,11(4):111-112
目的 选择84对患者97个周期的宫腔内人工授精(IUI)进行临床疗效分析。方法 按自然周期、克罗米芬(CC) 补佳乐 HCG、克罗米芬(CC) HMG HCG分为三组进行围排卵期IUI技术比较。结果 84对患者进行97含属期IUI,自然周期11个,有1例妊娠,妊娠率0.09%;克罗米芬(CC) 补佳乐 HCG组57个周期,有8例妊娠,妊娠率14.04%:克罗米芬(CC) HMG HCG组29个周期,有6例妊娠,妊娠率20.69%。结论 使用促排卵药物,尤其克罗米芬(CC) HMG HCG组,诱发排卵数目多,子宫内膜厚。妊娠率高。 相似文献