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B P?tzsch J Grulich-Henn R R?ssing D Wille G Müller-Berghaus 《Laboratory investigation; a journal of technical methods and pathology》1990,63(6):841-852
Human omental tissue has been used as a source for the isolation and cultivation of microvascular endothelial cells, but also for mesothelial cells. Since both cell types have several morphologic and functional features in common, concerns were raised whether endothelial cells can be separated from mesothelial cells by the methods described for the isolation of microvascular endothelial cells. In the present study, endothelial cells were identified in the capillaries of native human omentum by several endothelial-cell specific markers. von Willebrand factor was demonstrated by polyclonal and monoclonal antibodies, a lectin-specific ligand by Ulex europaeus I, and an endothelial-cell specific surface epitope by the monoclonal antibody, PAL-E. These markers were not found positive with mesothelial cells of native omentum. Mesothelial cells were identified by monoclonal antibodies against the intermediate filaments, cytokeratin and vimentin. After having demonstrated the specificity of the methods for the distinction between endothelial and mesothelial cells within native omentum, these methods were applied to omentum-derived cells previously claimed to be microvascular endothelial cells. These cultured cells proved to be negative for von Willebrand factor, Ulex europaeus I ligand and PAL-E epitope. In contrast to this, the cultivated cells stained positive to cytokeratin and vimentin. Furthermore, it was shown by immunoprecipitation studies that omentum-derived cells did not synthesize and secrete vWF, indicating the nonendothelial nature of these cells. Finally, electron microscopy demonstrated microvilli on the surface of cultivated omentum-derived cells indicative for the mesothelial origin of these cells. The data presented demonstrate that the cells obtained using the previously published methods for the isolation and cultivation of "microvascular endothelial cells" from omental tissue are of mesothelial and not of endothelial origin. Thus, a great number of data obtained with this type of omentum-derived cells thought to be microvascular endothelial cells need re-evaluation. 相似文献
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Paulo R. Dellani Martin Glaser Paulo R. Wille Goran Vucurevic Axel Stadie Thomas Bauermann Andrei Tropine Axel Perneczky Aldo von Wangenheim Peter Stoeter 《Journal of digital imaging》2007,20(1):88-97
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation. 相似文献
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An atypical pre-β-lipoprotein of human serum has been detected by agarose gel electrophoresis in four patients, three of whom were siblings. This lipoprotein differed from the pre-β lipoprotein previously observed with this technique by sedimenting on ultracentrifugation at density 1.006. 相似文献
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Blood velocities in 12 arteries were recorded by an ultrasonic doppler flowmeter in 11 young adults. Two major types of velocity patterns existed at rest. In certain arteries (the common carotid, the external carotid, the superficial temporal and the proper palmar digital arteries) flow was towards the periphery throughout the entire pulse cycle. Other arteries (the common femoral, the popliteal, the posterior tibial and the pedal artery) exhibited retrograde flow in part of the pulse cycle. In each individual a spontaneous variation between these two velocity patterns was observed in the subclavian, the axillary, the brachial and the radial artery. The velocity pattern of each artery is described, and absolute blood velocities at recognizable instances during the pulse cycle are given. The influence of peripheral resistance on the velocity pattern was investigated by reactive hyperaemia of the femoral artery. We find that not only is there an upward displacement of the resting femoral curve relative to the line of zero, but the shape of the velocity pattern is also changed. Our conclusion is that peripheral resistance is of major importance not only for the mean velocity, but also for the shape of the velocity pattern in the artery. 相似文献
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Alessio Nencioni Lucia Wille Giovanna Dal Bello Davide Boy Gabriella Cirmena Sebastian Wesselborg Claus Belka Peter Brossart Franco Patrone Alberto Ballestrero 《Clinical cancer research》2005,11(11):4259-4265
PURPOSE: Bcl-2 overexpression is frequently detected in lymphoid malignancies, being associated with poor prognosis and reduced response to therapy. Here, we evaluated whether Bcl-2 overexpression affects the cytotoxic activity of proteasome inhibitors taken alone or in association with conventional anticancer drugs or tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). EXPERIMENTAL DESIGN: Jurkat cells engineered to overexpress Bcl-2 were treated with proteasome inhibitors (MG132, epoxomicin, and bortezomib), anticancer drugs (etoposide and doxorubicin), TRAIL, or combinations of these compounds. Cell death and loss of mitochondrial transmembrane potential were detected by flow cytometry. Cytosolic relocalization of cytochrome c and SMAC/Diablo, caspase cleavage, and Bcl-2 and Mcl-1 levels were determined by immunoblotting. Nuclear factor-kappaB inhibition was done by retroviral transduction with a dominant-negative mutant of IkappaBalpha. RESULTS: Bcl-2 overexpression results in significant inhibition of apoptosis in response to proteasome inhibitors, antiblastics, and TRAIL. Addition of TRAIL to proteasome inhibitors results in a synergistic cytotoxic effect in Bcl-2-overexpressing cells, whereas this result is not reproduced by the combination of proteasome inhibitors with antiblastic drugs. Importantly, proteasome inhibitors plus TRAIL induce mitochondrial dysfunction irrespective of up-regulated Bcl-2. Bcl-2 cleavage to a fragment with putative proapoptotic activity and elimination of antiapoptotic Mcl-1 may both play a role in proteasome inhibitors-TRAIL cooperation. Conversely, nuclear factor-kappaB inhibition by proteasome inhibitors is per se insufficient to explain the observed synergy. CONCLUSIONS: Combined proteasome inhibitors and TRAIL overcome the apoptotic threshold raised by Bcl-2 and may prove useful in the treatment of chemoresistant malignancies with up-regulated Bcl-2. 相似文献
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回春液补肾助阳药效学的实验研究 总被引:2,自引:0,他引:2
回春液由人参、鹿茸、貂鞭等名贵中药组成。有补肾助阳,填精益气等功效。药效学研究证实,该药有促进幼鼠发育及增加去势大鼠前列腺——精液囊的重量,亦显著增加小鼠血红蛋白的含量,表明回春液有雄性激素样作用。 相似文献
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