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21.
The incidences, cooccurrences and epidemiological associations at term of the three common focal macroscopic placental lesions, infarcts, intervillous fibrin plaques (IVFP), and intervillous thrombi (IVT) were investigated as part of a population-based case-control study of small-for-gestational age (SGA) infants. Five hundred and nine placentas from women delivering SGA infants (10th percentile or less for gestational age) and 529 placentas from women delivering infants with birthweights appropriate for gestational age were examined using fixed protocols for identification of macroscopic lesions and microscopic diagnoses. One or more of these lesions were found in 280 placentas (28%), including infarcts in 150 (15%), IVFP in 132 (13%), and IVT in 64 (6%). Macroscopic misidentifications, particularly of IVFP as infarcts, emphasize the need for microscopic diagnoses. There were strong associations between the occurrence of any one type of lesion and cooccurrence of either of the other two, and these associations were site-dependent: between central (nonmarginal) infarcts and central IVFP (P = 0.0023); marginal infarcts and marginal IVFP (P < 0.0001); and between IVT (all central) and marginal infarcts (P < 0.0001) and marginal IVFP (P = 0.012). However, a study of associations between the incidences of placentas bearing each of the three lesions and 31 socio-demographic and pregnancy-related factors showed no associations in common. IVFP, an IVFP variant termed labyrinthine, and IVT did not show any of the independent associations demonstrated between infarcts and SGA, pregnancy-induced hypertension, nonsmoking, age at first pregnancy, and ethnicity. IVFP had no significant associations, and IVT were associated only with male gender. The study has shown that IVFP and IVT do not share the important clinical associations demonstrated for infarcts, but has not identified the pathogenetic factor or factors responsible for the frequent cooccurrence of these lesions. The maternal thrombophilias may have such a role.  相似文献   
22.
静脉血栓的抗磷脂蛋白抗体与抗凝血、纤维蛋白溶解关系   总被引:1,自引:1,他引:1  
为了探讨静脉血栓的病因病理及其与抗凝血、纤维蛋白溶解的关系 ,对 4 7例静脉血栓 (VT)患者用酶联免疫法检测抗心肌磷脂抗体 (ACA) ,用凝血法测定狼疮抗凝物 (LA)和抗活化蛋白C抗性 (APCR) ,用多聚酶链反应内切酶法鉴定因子VLeiden ,用发色底物法测定抗凝血酶Ⅲ (ATⅢ )、蛋白C(PC)、纤溶酶原 (Plg)、组织纤溶酶原激活物 (tPA)、组织纤溶酶原激活物抑制物 (tPAI)等抗凝血、纤维蛋白溶解活性。结果表明 :VT患者中 3 4 %有ACA和 (或 )LA阳性 ,其中以ACAIgG和LA为主 ;9.5 %的Plg缺乏 ,8.3 %的tPAI升高 (明显高于对照 ,P <0 0 0 5 ) ;ATⅢ、PC、tPA缺乏者依次为 4 .5 %、4 .5 %、2 .8% (与对照无差异性 ,P >0 .0 5 ) ;ATⅢ、PC、Plg联合缺乏者 1例 ;APCR未发现相应的factorVLeiden ;抗磷脂蛋白抗体 (APA)阳性和阴性组之间的各抗凝血和纤维蛋白溶解活性没有明显差异性 ;4例APCR阳性 ,3例ACA和 (或 )LA阳性 ,这 3例血浆和正常血浆混合后 2例APCR并没有完全得到纠正。结论 :抗磷脂蛋白抗体和纤维蛋白溶解异常是VT较多见的相关病理因素 ;LA和 (或 )ACA干扰蛋白C抗凝血途径 ,使之形成获得性APCR ,而此APCR可能是体内导致易栓的病因之一。  相似文献   
23.
原发性肝癌易侵犯门静脉形成门静脉癌栓(PVTT),引起肝内转移,加重门静脉高压,食道静脉曲张破裂大出血,导致临床治疗困难和治疗后复发.为探讨肝癌伴PVTT的立体定向放射治疗(SRT),2002年6月至2004年6月对86例肝癌伴PVTT无手术指征的患者进行SRT临床治疗,报道如下.  相似文献   
24.
Thrombus lysis by uPA, scuPA and tPA is regulated by plasma TAFI   总被引:3,自引:0,他引:3  
Summary.  The carboxypeptidase, TAFIa or CPU, is known to prolong plasma clot lysis by tissue plasminogen activator (tPA) and to have a role in thrombus stability in vivo. This current study examined lysis by urokinase (uPA) and single chain urokinase (scuPA) in addition to tPA. Further, we investigated the role of TAFIa in a model thrombus system, in which thrombi are formed under conditions of flow. We show that human thrombi, formed in vivo , and model thrombi both contain TAFI . No effect of thrombus TAFIa was observed in thrombus lysis assays, except when thrombi were bathed in plasma, in which case addition of potato tuber carboxypeptidase inhibitor (CPI) resulted in doubling of the rate of lysis. TAFIa inhibited lysis of model thrombi and plasma clots by uPA, scuPA in addition to lysis by tPA. The effect of TAFIa was more evident at high concentrations of plasminogen activator such as those used in thrombolytic therapy. Addition of plasminogen increased lysis and, in its presence, the enhancement by CPI was smaller. Thus the action of TAFIa could be partially overcome by plasminogen, whether lysis was by tPA, uPA or scuPA. This is consistent with TAFIa exerting its effect primarily through modifying the binding of plasminogen to fibrin and to a lesser extent through modification of the binding of tPA to fibrin.  相似文献   
25.
We present a case of multiple colorectal liver metastases with macroscopic portal vein thrombi. A 55-year-old woman presented to us with rectosigmoid cancer and presented with two liver metastases. The tumor in the posterior sector was associated with invasion of first order branches of the portal vein. We performed low anterior resection, hepatic posterior sectorectomy and partial left anterior sectorectomy. Both the colorectal cancer and liver tumors exhibited histological characteristics of moderately differentiated adenocarcinoma with a substantial amount of mucin production. The liver metastases were associated with prominent tumor thrombi in many branches of the portal vein. Stronger staining for endoglin (CD 105) than for Fas ligand (Fas L) and matrix metalloproteinase (MMP-2) was observed in both the colorectal cancer and metastatic liver tumor cells. Expression of the vascular endothelial growth factor within the tumor cells was seen in both the colorectal cancer as well as the metastatic liver tumor cells. Six months after the operation, she was diagnosed to have multiple, more than about 20 liver metastases, and in 9 months after the operation, the patient died. The colorectal cancer with liver metastases associated with portal vein tumor thrombosis was poor prognosis, found neoplastic microvessel formation.  相似文献   
26.
目的 评价血管内超声消融治疗急性动脉血栓的有效性和安全性。方法  12条实验犬制作双侧股动脉急性血栓模型 ,血栓长度 >5cm。每条犬一侧股动脉血栓予超声消融治疗 2min ,另一侧仅用消融导管作机械性穿插。观察超声组和对照组操作前后血栓处的血流变化 ,比较两组血栓段动脉经实验操作后的损伤系数及远端栓塞情况。结果 股动脉血栓超声消融后远端血流量为 (2 8.9± 4 .2 )ml/min ,显著高于对照组的 (9.6± 5 .0 )ml/min(P <0 .0 1) ;超声消融后TIMI分级指数为 2 .6 7± 0 .4 9,而对照组为 1.0 8± 0 .90 (P <0 .0 1) ;血栓处动脉损伤系数分别为 1.83± 0 .39和 1.6 7± 0 .4 9(P >0 .0 5 )。超声消融后无远端动脉栓塞现象。结论 血管内超声消融术治疗急性动脉血栓有效、安全  相似文献   
27.
This is a case series on three adult patients who contain left ventricular (LV) thrombus and the incremental benefits of live/real time three-dimensional transthoracic echocardiography (3DTTE) in comparison to two-dimensional transthoracic echocardiography (2DTTE) in evaluating LV thrombi. These cases illustrate that 3DTTE is of additional benefit by demonstrating the following: (1) cropping of a single 3DTTE apical dataset may be enough to provide comprehensive assessment of the LV in a timely manner even without breath holding in a not fully cooperative patient (2) it identifies the exact point of attachment of the thrombus to the left ventricular wall, (3) helps to delineate the absence or presence of focal echolucent areas within thrombi indicative of the presence and extent of clot lysis, which may have potential therapeutic and prognostic implications, and (4) provides more accurate assessment of thrombus mobility which has prognostic indications.  相似文献   
28.
We present a case of apical isolated congenital left ventricular (LV) diverticulum complicated with mural thrombosis in an adult and elucidate the echocardiographic features for differential diagnosis of LV outpouchings.  相似文献   
29.
We report the case of a 9-year-old girl with biopsy-proven renal thrombotic microangiopathy in thrombotic thrombocytopenic purpura (TTP), with particular reference to the glomeruloid structures. The renal biopsy sample from this TTP patient revealed platelet thrombus deposition, a glomeruloid structure and aneurysm with relative sparing of the glomeruli. The glomeruloid structure displayed a proliferation of mainly capillary-sized channels lined by Factor VIII-related, antigen-positive plump endothelial cells embedded in the edematous connective tissue. These glomeruloid vessels communicated with the aneurysmal segment at the end portion of the arteriolar branch. We believe that the glomeruloid structures in TTP represent not merely organization or recanalization of thrombus but rather active angiogenesis through aneurysmal dilation in the arteriolized vessel, probably initiated by platelet agglutination.  相似文献   
30.
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