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1.
Tumor necrosis factor-alpha (TNF-α) is a multifunctional Th1 cytokine and one of the most important inflammatory cytokines. In pregnancy, TNF-α influences hormone synthesis, placental architecture, and embryonic development. It was also shown that increased levels of TNF-α are associated with pregnancy loss and preeclampsia. Increased TNF-α levels in complicated pregnancy draw attention to trophoblast biology, especially migratory activity, syncytialisation, and endocrine function. Additionally, elevated TNF-α levels may affect the maternal-fetal relationship by altering the secretory profile of placental immunomodulatory factors, which in turn affects maternal immune cells. There is growing evidence that metabolic/pro-inflammatory cytokines can program early placental functions and growth in the first trimester of pregnancy. Furthermore, early pregnancy placenta has a direct impact on fetal development and maternal immune system diseases that release inflammatory (e.g., TNF-α) and immunomodulatory factors, such as chronic inflammatory rheumatic, gastroenterological, or dermatological diseases, and may result in an abnormal release of cytokines and chemokines in syncytiotrophoblasts. Pregnancy poses a challenge in the treatment of chronic disease in patients who plan to have children. The activity of the disease, the impact of pregnancy on the course of the disease, and the safety of pharmacotherapy, including anti-rheumatic agents, in pregnancy should be considered.  相似文献   
2.
采用人胎盘泌乳素(hPL)-亲和层析和抗人血清抗体-亲和层析技术,从胎盘匀浆中提取hPL纯品,经圆盘电泳、免疫电泳及交叉试验证实为单一成分。溴化氰水解后的产物,以高效液相色谱分析。分离出7个肽链片断峰,分别用hPL和人生长激素(hGH)放免法检测其活性,其中第6肽链片断无hGH免疫活性,若用此片断制备特异抗体,可避免与hGH出现交叉反应。  相似文献   
3.
The purpose of the present study was to determine whether cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). In patients undergoing CEA for internal carotid artery stenosis (≥70%), cerebral blood flow (CBF) was measured using single-photon emission computed tomography (SPECT) before and immediately after CEA. Microembolic signals (MES) were identified using transcranial Doppler during carotid exposure. Diffusion-weighted magnetic resonance imaging (DWI) was performed within 24 h after surgery. Of 32 patients with a combination of reduced cerebrovascular reactivity to acetazolamide on preoperative brain perfusion SPECT and MES during carotid exposure, 14 (44%) showed cerebral hyperperfusion (defined as postoperative CBF increase ≥100% compared with preoperative values), and 16 (50%) developed DWI-characterized postoperative cerebral ischemic lesions. Postoperative cerebral hyperperfusion was significantly associated with the absence of DWI-characterized postoperative cerebral ischemic lesions (95% confidence interval, 0.001–0.179; p = 0.0009). These data suggest that cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during carotid exposure in CEA, supporting the “impaired clearance of emboli” concept. Blood pressure elevation following carotid declamping would be effective when embolism not accompanied by cerebral hyperperfusion occurs during CEA.  相似文献   
4.
颜凌燕 《广东化工》2006,33(9):71-73
本文对多媒体在化工类课程教学中的应用进行研究与探讨,发现了一些不足,为了发挥多媒体的先进作用,本文提出了一些建议和可行的解决方法,借此来探讨课堂多媒体教学方法。  相似文献   
5.
Adrenal insufficiency is a complication of chronic corticosteroid therapy. Unexplained hypotension may be a manifestation of an adrenal insufficient state in patients with a history of corticosteroid therapy on hemodialysis. We present a series of five cases of patients on nocturnal home hemodialysis with hypotension as the main manifestation of adrenal insufficiency. Unexplained hypotension in patients with a history of corticosteroid therapy should prompt the managing clinician to consider adrenal insufficiency as a possible cause.  相似文献   
6.
目的:探讨彩色多普勒超声对胎盘滞留的诊断及治疗价值。方法:分析45例胎盘滞留患者初步临床诊断、初步临床诊断联合彩色多普勒超声诊断与最终诊断的符合情况。结果:初步临床诊断联合彩色多普勒超声对胎盘嵌顿及胎盘粘连诊断与最终诊断的符合率明显高于初步临床诊断与最终诊断的符合率(P〈0.05),对胎盘粘连的漏诊率明显低于初步临床诊断(P〈0.05)。结论:彩色多普勒超声可提高临床对胎盘嵌顿及胎盘粘连诊断的准确率,减少胎盘粘连的漏诊率,并可指导临床处理。  相似文献   
7.
目的:探讨二尖瓣成形术(MVP)多技术复合应用治疗复杂性二尖瓣关闭不全(MI)的临床效果。方法对23例复杂性MI患者按常规在全身麻醉中度低温体外循环下手术,综合应用多项MVP技术进行二尖瓣修复,包括瓣矩形切除、前叶三角形切除、腱索缩短、腱索转移、缘对缘二孔化、置入人工腱索、置入人工瓣环等,术中采用注水实验和经食管超声心动图检查评估成形效果。结果全组病例围术期无死亡,平均体外循环时间(114±4)min,平均主动脉阻断时间(69±21)min。术后1周心脏彩超复查:二尖瓣无任何反流或微量反流18例,轻度反流5例。出院时心功能均明显改善,其中NYHAⅠ级14例,Ⅱ级9例。随访中1例缺血性病变患者术后9个月二尖瓣由微量反流增加至中度反流,其余患者恢复良好,无异常出血、血栓栓塞、心内膜炎等重大并发症发生。结论对复杂性MI患者,根据二尖瓣病因与病变部位,合理选择MVP多技术复合应用治疗,可获得良好的临床疗效。  相似文献   
8.
Biomarkers for placental dysfunction are currently lacking. We recently identified SPINT1 as a novel biomarker; SPINT2 is a functionally related placental protease inhibitor. This study aimed to characterise SPINT2 expression in placental insufficiency. Circulating SPINT2 was assessed in three prospective cohorts, collected at the following: (1) term delivery (n = 227), (2) 36 weeks (n = 364), and (3) 24–34 weeks’ (n = 294) gestation. SPINT2 was also measured in the plasma and placentas of women with established placental disease at preterm (<34 weeks) delivery. Using first-trimester human trophoblast stem cells, SPINT2 expression was assessed in hypoxia/normoxia (1% vs. 8% O2), and following inflammatory cytokine treatment (TNFα, IL-6). Placental SPINT2 mRNA was measured in a rat model of late-gestational foetal growth restriction. At 36 weeks, circulating SPINT2 was elevated in patients who later developed preeclampsia (p = 0.028; median = 2233 pg/mL vs. controls, median = 1644 pg/mL), or delivered a small-for-gestational-age infant (p = 0.002; median = 2109 pg/mL vs. controls, median = 1614 pg/mL). SPINT2 was elevated in the placentas of patients who required delivery for preterm preeclampsia (p = 0.025). Though inflammatory cytokines had no effect, hypoxia increased SPINT2 in cytotrophoblast stem cells, and its expression was elevated in the placental labyrinth of growth-restricted rats. These findings suggest elevated SPINT2 is associated with placental insufficiency.  相似文献   
9.
启迪 《时代建筑》2003,(4):88-91
1、现实与挑战 随着WTO加入,设计市场的开放,民营事务所的涌现,建筑设计行业的原有格局已被打破,大院在行业内的垄断地位已受到各方面的挑战,看淡甚至看衰大院前景的大有人在,历史又一次将大院推到了前台。  相似文献   
10.
目的:观察子宫颈神经内分泌小细胞癌合并妊娠的胎盘超微结构.方法:利用透射电镜观察一例子宫颈神经内分泌小细胞癌合并妊娠的癌组织及胎盘超微结构.结果:在胎盘的合体滋养层内及绒毛间质均可见到癌细胞,有些癌细胞的胞质尚可见电子致密的神经内分泌颗粒.结论:电镜检查有助于证实宫颈神经内分泌小细胞癌的胎盘转移.  相似文献   
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