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Summary Murine teratocarcinoma models have been widely used in the study of several biological processes including early mammalian development and neoplasia. The relatively new human germ-cell tumor models have an important role in the study of human embryogenesis and neoplasia since human embryogenesis differs significantly from species such as mice and the histopathology of human testicular germ-cell tumors differs substantially from tumors obtained in highly inbred strains of mice. In this report we describe the use of human germ-cell lines in the study of cell differentiation; expression of early embryonic antigens; production of the major regulator of erythropoiesis, erythropoietin; and production of retrovirus-like particles.Supported in part by a grant from the Minnesota Medical Foundation 相似文献
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The use of streptokinase to treat renal artery thromboembolism 总被引:1,自引:0,他引:1
A Steckel J Johnston D S Fraley F J Bruns D P Segel S Adler 《American journal of kidney diseases》1984,4(2):166-170
The effects of streptokinase are difficult to determine. Furthermore, it has toxic side effects, and renal function may not recover from its use. However, because of favorable experiences with this drug in the early treatment of venous thromboembolism and following myocardial infarction, as well as the favorable findings with early perfusion in the dog model, the use of local streptokinase may be justified if the infusion is begun early, preferably within four to six hours. 相似文献
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甘草类黄酮对四氯化碳致小鼠急性肝损伤的影响 总被引:48,自引:0,他引:48
甘草类黄酮(GF)是从甘草根中提得。本文结果表明,预先ig GF 200,400,600mg·kg-1·d-1×2d能显著降低CCl4所致血清谷丙转氨酶,乳酸脱氢酶活性的升高以及肝内丙二醛含量的增加,其作用呈剂量依赖性。GF可减轻CCl4所致的肝脏坏死,但对血清内酶的活性没有抑制作用,也不减少正常小鼠血清中酶的活性。GF的肝保护作用可能与其抗脂质过氧化作用有关。 相似文献
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Matson GB; Twieg DB; Karczmar GS; Lawry TJ; Gober JR; Valenza M; Boska MD; Weiner MW 《Radiology》1988,169(2):541-547
Localized phosphorus-31 magnetic resonance (MR) spectroscopy in humans has previously been accomplished with surface coils by means of depth-resolved surface coil spectroscopy or rotating frame experiments, in which the extent of tissue sampled critically depends on surface coil placement. The authors' goal was to modify the surface coil image-selected in vivo spectroscopy (ISIS) experiment to accomplish three-dimensional volume selection through application of selective pulses in the presence of B0 gradients. Advantages of ISIS include the ability to use proton images to define the volume of interest (VOI) and reduced dependence on exact positioning of the surface coil. However, rapid replication of the surface coil ISIS experiment can cause spectral contamination from signals originating outside the VOI. A modified version of the ISIS experiment was developed to alleviate contamination under conditions of rapid replication. Applications of localized P-31 MR spectroscopy for observation of high-energy phosphorus metabolites are presented in human liver, heart, and transplanted and normal kidney. 相似文献