光照后胎儿脐动脉脑动脉血流变化

为了证实胎儿对经母腹壁光照可产生应答反应，我们通过彩色多谱勒超声诊断仪观察了３０名妊娠３４－４１周孕妇的胎儿，光照前后及动脉，脑动脉血流变化。     

彩色多谱勒超声在诊断胎儿生长受限(FGR)中的应用

目的评价生长受限胎儿大脑中动脉和脐动脉血流多谱勒特点、它们的相互关系以及新生儿预后。方法检测65例生长受限胎儿剖宫产前大脑中动脉和脐动脉血流多谱勒波形中搏动指数。结果显示有如下3种特点：1期有39例，UAPI〈MCAPI（没有脑保护效应）；2期有23例，UAPI〉MCAPI（有脑保护效应）；3期3例，随舒张未期血流减少搏动指数升高或出现舒张末期反流，这种情况诊断为脑保护效应失代偿。分娩时检测脐带血气数据，并进行两两比较。结果每一时期分娩时孕周和体重有显着性差异（P〈0．05）。各个时期新生儿平均体重显着低于标准体重（国际标准），这提示生长受限。3期PH期和剩余碱明显不同于其它两期（P〈0．05）。结论脑保护效应失代偿生长受限胎儿分娩提前，并且有严重生长受限和轻度代谢性酸中毒。MCAPI从低到高的变化以及UAPI进行性增加可预示胎儿严重生长受限。     

高血压病人阻力动脉重构和微血管功能障碍

目的研究原发性高血压（EH）阻力动脉重构及其微血管整合功能。方法对EH病人30例和正常对照组30例，采用上肢节段性血压、Doppler超声、激光Doppler血流仪等无创性检查方法，评估阻力动脉结构、功能和微循环变化。结果①EH病人阻力动脉段向上延伸（P〈0．05），包括微动脉和小动脉；②阻力动脉重构特征：小动脉管壁增厚（P〈0．01）、壁／腔比值增大（P〈0．01），腔径轻度减少（P〉0．05）；管壁僵硬度增加，脉波传导速度增快（P〈0．001）；血流介导内皮依赖性血管扩张障碍和收缩作用减弱。③同时，皮肤毛细血管压升高（P〈0．01），这与阻力动脉重构引起微循环“调节机制储备”受损和上游高血压跨壁传输作用的两种机制有关。结论高血压病人阻力动脉段向上延伸，伴存动脉结构、机械特性和血管舒缩运动异常，并导致微血管系统整合功能障碍。测定这些改变的相关指标．有助于评估微血管病变程度和降压治疗的外周效应。     

血管性头痛与脑动脉血流变化

本文采用TCD技术测定了200例血管性头痛患者的脑动脉血流变化，结果发现，间歇组（100例）平均脑动脉血流速度明显快于发作组（100例），它们之间有非常显著性差异（P＜0．01）。     

胎儿脉络丛囊肿与大脑中动脉阻力指数关系的探讨

目的探讨胎儿脉络丛囊肿与大脑中动脉阻力指数（RI）的关系。方法测量59例脉络丛囊肿胎儿的囊肿大小及大脑中动脉的RI值,并随访至产前,以正常同孕龄胎儿作为对照组。对脉络丛囊肿大小及大脑中动脉的RI值进行统计学分析。结果脉络丛囊肿组与正常对照组的大脑中动脉RI值差异无显著性（P〉0．05）,32周后脉络丛囊肿消失的胎儿与未恢复正常的胎儿其大脑中动脉的RI值差异也无显著性（P〉0．05）。结论胎儿脉络丛囊肿与大脑血供情况无明显的关系。     

妊娠期胎儿肱动脉和脐动脉血流的多普勒超声研究

该研究是评价胎儿肱动脉的阻力指数在整个妊娠期的变化以及它与脐动脉阻力指数的关系。应用 HP公司SSH14 0型彩色多普勒超声诊断仪对 71例正常孕妇的 71个胎儿的 15 4条肱动脉和脐动脉在 12～ 4 0周间进行检查。并在每一孕周对胎儿肱动脉的阻力指数的平均值、标准差、变化范围及 t分布的 95 %自信区间进行计算。显示胎儿肱动脉阻力指数在怀孕初期尽管相对较低 ,仍为高阻力血流频谱 ,并随着孕周增加轻度升高 ,而胎儿脐动脉的阻力指数呈渐进性减少。认为氧合作用好的正常胎儿肱动脉阻力指数较高 ,脐动脉的阻力指数在整个孕期呈渐进性减小妊…     

胎心监护、胎儿脐动脉及大脑中动脉血流检测在预测胎儿窘迫中的作用

目的 探讨胎心监测联合彩超脐动脉和大脑中动脉血流检测预测胎儿窘迫的作用。方法 选取2018年1月至2021年10月临沂市妇幼保健院收治的365例孕妇,根据胎儿窘迫诊断标准分为观察组（n=186例）、对照组（n=179例）,所有孕妇均进行产前胎心监护、彩超脐动脉和大脑中动脉血流监测及新生儿阿普加评分（Apgar评分）和脐带动脉血血气分析。比较观察组和对照组在胎心监护、彩超检测的差异有无统计学意义,比较两组单独及联合检测的灵敏度、特异度、阳性预测值、阴性预测值和约登（Youden）指数等。结果 胎心监护、脐动脉和大脑中动脉血流检测之间无统计学意义（P>0.05）,三者联合监测诊断胎儿窘迫的灵敏度、特异度、阳性预测值、阴性预测值和Youden指数均高于单独检测,差异均有统计学意义（P<0.05）。结论 与单独监测相比,胎心监测联合彩超脐动脉和大脑中动脉血流检测诊断胎儿窘迫可互补三者之间的不足,提高了诊断的灵敏度、特异度及阳性预测值和阴性预测值。     

银杏叶提取物对煤工尘肺血液流变学的影响

作者选择了血粘度高于健康人（P＜0．001）的煤工尘肺住院患者30人，进行银杏叶片取药前后自身对照观察。结果发现，经过六周治疗后，尘肺患者的血流变学指标，除血球压积（Hct，P＞0．05）外，其余各项指标均有显著改变（P＜0．05），血浆粘度改变尤为显著（P＜0．001）。就其对尘肺的治疗机理等进行了探讨。     

脐动脉血流速度监测的临床意义-附118例异常分析

目的利用脐动脉血流速度监测孕晚期及分娩期胎儿的脐动脉阻力,通过对脐动脉血流速度波形分析,结合胎心监护,间接判断胎盘血流,脐带血流速度有无异常,决定正确的分娩方式,有效降低胎儿宫内窘迫及新生儿窒息的发生率,具有重要的临床意义.方法检测842例孕妇,其中S/D、PI、RI增高者118例(异常组),随机选择正常者100例(正常组),配合NST监护,将两组进行比较.结果合并IUGR及妊高症时S/D,RI值变化最大,分别为S/D6.47 ± 0.45、4.14±0.18,RI0.97±0.33、1.01 ± 0.65,监护阳性行剖宫产者25例,与正常组比较,P＜0.005,但两组新生儿Apgar平分比较P＞0.01.结论说明通过胎儿脐动脉血流监测能及时发现并处理胎儿宫内异常,新生儿预后良好.     

急性肺动脉高压肺血管力学特性的评价

本文通过静脉持续滴注血检素A2类似体U46619复制急性肺动脉高压实验模型，借助右心导管技术和利用压力波形面积确定动脉顺应性的改进方法，评价急性肺动脉高压状态下的肺血管力学特性。实验结果发现，当平均肺动脉压从2.60±0．3kPa上升至3.75±0.45kPa后；心排量（CO）无显著性变化（1．85±0．21vs1．21±0．25l／min；P＞0.05），而肺小动脉血管阻力（PVR）明显升高（31.4±9．4vs148．7±12．3kPa·s／L，P＜0．01）与肺动脉平均压相对应的血管顺应性Cm显著降低（12．43±2．62vs10．30±3．12ml／kPa，P＜0．05），而反映肺血管壁固有结构特性的零压顺应性Co无明显改变（15.22±2.98vs14.31±3.49ml／kPa，P＞0．05。本实验提示，在急性肺高压状态，肺小动脉收缩引起的肺血管阻力变化是关键因素，选择治疗急性肺高压的扩血管药物应偏重于主要作用于小动脉血管的药物。     

Paradoxical rise in brainstem PO(2) following umbilical cord occlusion in full-term rat fetuses

Although the fetus experiences severe hypoxia and ischemia during delivery, the fetal brain is protected from hypoxic-ischemic insults by unknown mechanisms. To investigate this phenomenon, fetal asphyxia was induced in pregnant rats by occlusion of the umbilical cord. Rather than producing cerebral hypoxia, the brainstem PO(2) of at-term fetuses increased following umbilical cord occlusion, while brainstem blood flow was markedly reduced. This paradoxical increase in brainstem PO(2) during asphyxia occurred in the majority of at-term fetuses, less frequently in fetuses 1 day prior to term and did not occur in animals following birth. Because occlusion of the umbilical cord prevents maternal delivery of oxygen to the fetus, we propose that the ability to maintain PO(2) is the result of pre-existing fetal stores of oxygen or from de novo generation of oxygen in the fetal brainstem.     

Haemodynamic changes in IUGR fetus with chronic hypoxia evaluated by fetal heart-rate monitoring and Doppler measurement of blood flow velocity

The measurement of fetal blood flow velocity and 24 h monitoring of fetal heart-rate (FHR) using a computer were performed to clarify the haemodynamics of growth-retarded fetuses with chronic hypoxia. One hundred normal-growth and 18 growth-retarded fetuses were analysed. All the growth-retarded fetuses with chronic hypoxia were characterised by abnormal blood flow velocity waveforms (with the pulsatility index in the descending aorta below the −1·0 SD and in the middle cerebral artery above the +1·0 SD for our reference range, from 100 normal-growth fetuses). In the latter, the incidence of accelerations of defined size and variability in FHR patterns showed a diurnal variation after 30 weeks' gestation. The initial change in FHR patterns during hypoxia in 11 growth-retarded fetuses, resulting in fetal distress, was a derangement of diurnal variations in FHR patterns, followed by a decrease in variability. A rapid increase in blood flow velocity in the middle cerebral artery with the advance of hypoxia was observed before the onset of distress. Maternal low-dose oxygen inhalation elicited a temporary increase in FHR variability in the growth-retarded but not in normal fetuses. Re-inhalation after 1 h elicited a similar change, suggesting that intermittent rather than continuous, oxygen inhalation may be more effective.     

Fetal haemodynamics before and after treatment of maternal hypertension in pregnancy

The haemodynamics of fetuses of 15 pregnant women who developed hypertension during the last trimester of pregnancy were investigated before and after antihypertensive treatment using the ultrasound-Doppler method for non-invasive measurements of blood flow, and the results were compared to those from investigations of fetuses from normal pregnancies. In the untreated condition, significant reduction of blood flow was demonstrated in the fetal descending aorta (p less than 0.01) and in the umbilical vein (p less than 0.02). The resistance to flow, expressed as the Pulsatility Index, was significantly elevated (p less than 0.001). A significant correlation was shown between Pulsatility Index and maternal diastolic blood pressure (p less than 0.001) and a significant negative correlation between blood velocity in fetal aorta and maternal diastolic blood pressure (p less than 0.01). Treatment resulted in significant reduction of resistance to flow, which remained normal for the rest of the pregnancy. It is concluded that fetal haemodynamics are affected by maternal hypertension during pregnancy. The results suggest that the fetus also suffers from hypertension. Therapy with oral alpha-methyldopa and labetalol combined with volume expansion with human albumine normalised fetal circulation and kept it normal for the remainder of the pregnancy.     

Fetal cerebral, cardiovascular and metabolic reactions to intermittent occlusion of ovine maternal placental blood flow

In 10 mature, acutely exteriorized fetal sheep cardiovascular, cerebral and metabolic reactions were followed during intermittent occlusions of maternal placenta blood flow. The response was analysed from blood pressure, heart rate, myocardial contractility, combined cardiac output, ST waveform analysis of the fetal ECG, and from the evoked EEG response. The metabolic response was judged from blood gases, pH, lactate and circulating catecholamines. Basal values were within the range seen in the 'chronic' fetal lamb preparation. During moderate asphyxia, achieved by 10 1 min occlusions separated by 2 min periods of free maternal aorta blood flow, cardiovascular performance was increased with a substantial catecholamine surge but minor effects on cerebral and metabolic functions. During the marked asphyxia, achieved by five 2 min occlusions, marked metabolic changes occurred together with abolition of cerebral function. Forty-five minutes after asphyxia, 9/10 of the fetuses had regained cerebral, metabolic and cardiovascular functions.     

大脑中动脉血流变化对估计脐带绕颈胎儿预后的价值

目的探讨大脑中动脉血流变化对估计脐带绕颈胎儿预后的价值。方法选取2006年1月~2006年9月足月妊娠妇女51例。其中观察组39例,均为脐带绕颈一周并经阴道分娩。结合胎儿预后将观察组分为胎窘组(15例)和正常组(24例)。对照组12例,为随机选择的同期正常妊娠并顺产的妇女。应用彩色多普勒超声技术对全部孕妇于临产前和活跃早期检测胎儿大脑中动脉阻力指标-收缩期峰值流速/舒张末期流速(S/D)、阻力指数(RI)和搏动指数(PI)。结果(1)临产前,胎窘组胎儿大脑中动脉血流S/D、RI、PI值较对照组和正常组皆显著升高(P<0.05);而对照组和正常组比较,差异不显著(P>0.05)。(2)活跃早期胎窘组胎儿大脑中动脉血流S/D、RI、PI值较对照组和正常组皆显著降低(P<0.05);而对照组和正常组比较,差异不显著(P>0.05)。结论大脑中动脉血流阻力指标的变化与脐带绕颈胎儿不良预后密切相关;临产前监测脐绕颈胎儿MCA血流阻力指标的变化可以作为早期评估胎儿预后的理想方法。     

Extracellular glutamate levels and neuropathology in cerebral white matter following repeated umbilical cord occlusion in the near term fetal sheep

Umbilical cord occlusion causes fetal hypoxemia which can result in brain injury including damage to cerebral white matter. Excessive glutamate release may be involved in the damage process. This study examined the relation between extracellular glutamate levels in the cerebral white matter of the ovine fetus during and after intermittent umbilical cord occlusion and the degree of resultant fetal brain injury. Fetal sheep underwent surgery for chronic catheterisation and implantation of an intra-cerebral microdialysis probe at 130 days of gestation (term approximately 147 days). Four days after surgery (day 1), seven fetuses were subjected to 5x2 min umbilical cord occlusions, and on the following day (day 2) they were subjected to either 4 or 5x4 min umbilical cord occlusions; seven fetuses served as controls. Microdialysis samples were collected before, during and after the umbilical cord occlusions to determine extracellular glutamate levels in the cerebral white matter. Fetal blood gas status was measured and the fetal electrocorticogram was recorded continuously. During the periods of umbilical cord occlusions on both days 1 and 2, fetal arterial oxygen saturation, arterial partial pressure of oxygen and arterial pH decreased (P<0.05) while arterial partial pressure of carbon dioxide increased (P<0.05). All fetuses showed episodes of isoelectric electrocortical activity during umbilical cord occlusions on both days 1 and 2. In fetuses with patent microdialysis probes there were marked increases of glutamate efflux in the cerebral white matter following umbilical cord occlusion. Fetal brains were removed at autopsy on day 5 and subjected to histological assessment. Brain damage was observed in all fetuses exposed to cord occlusion, particularly in the periventricular white matter, with the most extensive damage occurring in the fetuses with the greatest increases in glutamate levels. We conclude that, in the unanesthetised fetus in utero, glutamatergic processes are associated with umbilical cord occlusion-induced brain damage in the cerebral white matter.     

Stimulation of Human Fetal Lymphocytes by Lipopolysaccharide B in Culture

Cultures of Isopaque-Ficoll-isolated lymphocytes from three human sources were compared with respect to the effect of mitogens. The cell sources were maternal blood immediately after delivery, cord blood, and blood obtained by heart puncture of 10–20-week aborted fetuses. Lipopolysaccharide B (LPS) induced incorporation of tritiated thymidine, blastic transformation, and mitotic activity in cord and fetal, but not maternal, cells. The stimulation reached a maximum on days 4–8 of culture. It was stronger than the spontaneous transformation often displayed by fetal cells. If fetal cells spontaneously occurring in the blood of pregnant women were to react in 3 similar way, it should be possible to selectively stimulate the fetal cells with LPS. Such transformed fetal cells could then be isolated from cultures of maternal blood samples and used for antenatal diagnosis of fetal disease.     

The cardiovascular and renal effects of acute and chronic inhibition of nitric oxide production in fetal sheep

The acute and long-term effects of blockade of nitric oxide (NO) production were studied in six chronically catheterised fetal sheep aged from 116 and 118 days; six untreated fetal sheep received injections of saline. Injection of 10 mg (kg maternal body wt)(-1) of the nitric oxide synthase (NOS) inhibitor N(omega)-nitro-L-arginine (NOLA) to the fetus, caused an immediate rise in fetal mean arterial pressure (MAP, P < 0.005) and a reflex fall in fetal heart rate (FHR, P < 0.001). Plasma renin concentration (PRC) fell from 8.4 +/- 3.3 to 1.5 +/- 0.3 ng ml(-1) h(-1) (P < 0.001) and was dependent on MAP (P = 0.001). Glomerular filtration rate (GFR) tended to increase, but renal blood flow (RBF) velocity decreased (P < 0.001). Thus filtration fraction (FF) increased (P < 0.025). Urine flow and sodium excretion increased (P < 0.001 for both). Fractional sodium reabsorption decreased (P < 0.05). In fetuses treated with NOLA, arterial pressure was found to affect glomerular haemodynamics and renal tubular handling of sodium. No such relationships were observed in untreated fetuses. The vascular responses to acetylcholine tended to be less (P = 0.07) and the responses to noradrenaline were enhanced in NOLA-treated fetuses. There were no changes in untreated fetuses. Fetuses were then injected twice daily with either 5 mg kg(-1) NOLA or saline for the next 2 days. On the 4th day, injection of 10 mg kg(-1) NOLA did not have any effects on MAP, FHR or renal function. However, the pressor responses to angiotensin II (Ang II) were enhanced (P < 0.005), as was the response to noradrenaline but to a lesser extent. It is concluded that endothelial production of NO maintains normal fetal blood pressure, renal vascular resistance and fetal renal function. When NO production was blocked by repeated injections of NOLA, other vasodilator pathways took over the maintenance of cardiovascular and renal vascular tone. However, alterations in both cardiovascular and renal function were still present. That is, there was increased pressor sensitivity to exogenous Ang II and unmasking of effects of arterial pressure on glomerular and tubular function.     

正常新生儿出生时的生长抑素和神经紧张素水平

采用放射免疫技术，测定了14例正常足月新生儿及其母亲血中生长抑素和神经紧张素浓度，发现脐动脉生长抑素和神经紧张素浓度明显高于脐静脉浓度（P均＜0．01），二者均明显高于分娩后即刻母亲静脉血中相应的激素浓度（P均＜0．01）；脐动脉pH与脐动脉生长抑素和神经紧张素浓度存在一种负相关关系（P均＜0．01）。提示脐血中高浓度的生长抑素和神经紧张素极可能是胎儿源性的，且可能与分娩引起的胎儿应激有关。     

超声多普勒预测胎儿生长受限

目的为研究超声多普勒对预测胎儿生长受限(FGR)及预后的作用及意义。方法对我院选取84例FGR组和同期住院的100例正常妊娠组作为对照,进行脐血流彩色多普勒检查。结果 1.FGR组脐动脉及胎儿大脑中动脉搏动指数(PI)较对照组明显减小,两者相比差异有统计学意义(P分别<0.05,<0.01)。2.FGR组脐动脉及胎儿大脑中动脉S/D比值较对照组明显增高,差别有统计学意义。3.脑-胎盘比值越小提示胎儿预后越差。