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31.
Y Xu D Zagoura C Keck D Pietrowski 《Experimental and clinical endocrinology & diabetes》2006,114(10):590-595
Corpus luteum development is regulated by gonadotropins and accompanied by extremely rapid vascularization of the avascular granulosa cell compartiment by endothelial cells (EC). The proliferation of Granulosa cells (GC) and EC is a complex interplay and takes place in a spatially and temporarily coordinated manner. The erythropoietin-producing hepatoma amplified sequence (Eph) receptors and their ligands-the ephrins- are a recently detected family of membrane located protein tyrosine kinases which play a crucial role in the growth and development of nerve and blood vessel network. We report about the mRNA expression pattern of Ephs and their ligands in human GC, in human EC, and in carcinoma cell lines OvCar-3 and Hela. The mRNA of EphA4, EphA7, ephrinA4, ephrinB1 and ephrinB2 was detected in GC and EC, while EphA2 was expressed only in GC. The expression of various Ephs and ephrins did not change in GC after stimulation with human chorion gonadotropin. Our study analyzes for the first time the expression of the complete human Eph/ephriny-system in GC and in EC. The remarkable similarity between these two cell types supports the theory of a functional relationship of EC and GC. In addition, it was shown that hCG is not a major determinant of Eph/ephrin regulation in GC. 相似文献
32.
Amyloidosis is a systemic disease that usually occurs in the gastrointestinal tract or in muscular or adipose tissue. Primary amyloidosis of the urinary bladder is a rare disease that can mimic bladder cancer on cystoscopic examination as well as in its clinical presentation of painless gross hematuria. This report describes a 49-year-old male with repeated painless gross hematuria, who underwent transurethral resection of a suspected bladder tumor. Pathologic examination revealed papillary urothelial hyperplasia with vascular ectasia and no signs of malignancy. Massive gross hematuria occurred 2.5 years later. Cystoscopy showed multiple papillary lesions with yellowish-brown submucosal plaques on the posterior bladder wall. A second transurethral tumor resection was performed and histologic examination revealed plasma cell infiltration and eosinophilic amorphous deposits in the subepithelial stroma and vascular wall. The deposits were positive for Congo red and apple-green birefringence under polarized light examination but negative for Masson's trichrome stain, indicating that they were not fibrotic in nature. Hence, the diagnosis of amyloidosis of the urinary bladder was confirmed. Screening for amyloidosis was negative in other organ systems and the patient has remained disease-free up to the last follow-up 4 years after the second transurethral resection. Amyloidosis should be considered in the differential diagnosis of patients with recurrent hematuria who have symptoms characteristic of bladder cancer but negative pathologic study for malignancy. Correct diagnosis relies on clinical alertness and the use of a special staining technique during pathologic examination. 相似文献
33.
目的 探讨急性胆囊炎行腹腔镜胆囊切除术的手术时机,并总结操作技巧。方法 回顾性分析2000年6月~2005年6月265例腹腔镜胆囊切除术治疗急性胆囊炎的临床资料。结果 265例中手术成功244例,成功率92.1%。中转开腹21例,其中小于72小时(Ⅰ组),超过72小时(Ⅱ组)的中转率分别为3.1%(4/129),12.5%(17/136)。Ⅰ组与Ⅱ组比较成功率无明显差别(P〉0.05)。全组无死亡病例,也无严重并发症发生。结论 急性胆囊炎行腹腔镜胆囊切除术安全可行,只要无内科禁忌证,应积极开展腹腔镜手术。 相似文献
34.
Alex Zacharek Jieli Chen Xu Cui Ang Li Yi Li Cynthia Roberts Yifan Feng Qi Gao Michael Chopp 《Journal of cerebral blood flow and metabolism》2007,27(10):1684-1691
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2. 相似文献
35.
Lei Ding Christopher Wilke Bobby Xu Xiaoliang Xu Wim van Drongelen Michael Kohrman Bin He 《Journal of clinical neurophysiology》2007,24(2):130-136
SUMMARY: It is desirable to estimate epileptogenic zones with both location and extent information from noninvasive EEG. In the present study, the authors use a subspace source localization method (FINE), combined with a local thresholding technique, to achieve such tasks. The performance of this method was evaluated in interictal spikes from three pediatric patients with medically intractable partial epilepsy. The thresholded subspace correlation, which is obtained from FINE scanning, is a favorable marker, which implies the extents of current sources associated with epileptic activities. The findings were validated by comparing the results with invasive electrocorticographic (ECoG) recordings of interictal spike activity. The surgical resections in these three patients correlated well with the epileptogenic zones identified from both EEG sources and ECoG potential distributions. The value of the proposed noninvasive technique for estimating epileptiform activity was supported by satisfactory surgery outcomes. 相似文献
36.
Z-Y Sun J Wei L Xie Y Shen S-Z Liu G-Z Ju J-P Shi Y-Q Yu X Zhang Q Xu G P Hemmings 《European psychiatry》2004,19(6):354-357
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors. 相似文献
37.
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39.
CT增强扫描在评价NSCLC血管生成中的临床意义 总被引:3,自引:3,他引:0
目的 探讨非小细胞肺癌 (NSCLC)血管内皮生长因子 (VEGF)的表达水平与CT增强程度的关系 ,从影像学角度评价肿瘤血管生成在肺癌诊断、治疗及淋巴结转移中的临床价值。方法 对 30例NSCLC病人进行动态螺旋CT扫描 (SCT) ,测量病灶增强幅度 ,并利用免疫组化技术检测VEGF。对病灶增强值、VEGF阳性表达及淋巴结转移情况进行统计学分析。结果 30例肺癌病人CT增强值均数为 (36 .2 8± 6 .41 )HU ,VEGF阳性表达 2 1例 ,阴性表达 9例。VEGF在中晚期的阳性表达高于早期病人 (Ρ<0 .0 5) ,淋巴结转移组高于非淋巴结转移组 (Ρ <0 .0 5) ;癌灶增强值与VEGF阳性表达、肿瘤分期及淋巴结转移亦呈正相关。结论 NSCLC的CT增强程度能够反映肿瘤的血管生成 ,并与淋巴结转移密切相关 ,有助于肺癌的诊断、TNM分期 ,而且可以从肿瘤分子生物学行为方面补充目前肺癌分期方法的不足 相似文献
40.