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31.
Needle biopsy of renal allografts: comparison of two techniques 总被引:2,自引:0,他引:2
Bogan ML; Kopecky KK; Kraft JL; Holladay AO; Filo RS; Leapman SB; Thomalla JV 《Radiology》1990,174(1):273-275
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications. 相似文献
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Human decidual stromal cells express alpha-smooth muscle actin and show ultrastructural similarities with myofibroblasts. 总被引:5,自引:0,他引:5
C Oliver M J Montes J A Galindo C Ruiz E G Olivares 《Human reproduction (Oxford, England)》1999,14(6):1599-1605
Previous reports in human and mouse material demonstrated that decidual stromal cells expressed antigens associated with haematopoietic cells, exerted immune functions, and originated from bone marrow. These findings suggested that these cells belonged to the haematopoietic lineage. We purified and expanded in culture precursors of human decidual stromal cells, and found in electron microscopic images that the ultrastructure of these cells was similar to that of myofibroblasts, which are of mesenchymal origin. The relationship between these two types of cell was confirmed by the detection (by flow cytometry) in the decidual precursors of alpha-smooth muscle actin, a contractile microfilament expressed solely by smooth muscle cells, myofibroblasts and related cells. This filament was also detected in decidual stromal cells decidualized in vitro by the effect of progesterone. We also found vimentin in decidual precursors and decidualized cells. This intermediate filament has been previously reported to be expressed by all decidual stromal cells and also by myofibroblasts. Desmin, another intermediate filament expressed by myofibroblasts, was not detected in the decidual precursors; however, this filament was observed in decidualized cells. The expression of alpha-smooth muscle actin by decidual stromal cells was also found by immunostaining in cryostat sections of early decidua. Our results suggest that decidual stromal cells are related to myofibroblasts. 相似文献
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丹参素胶囊活血化瘀作用的实验研究 总被引:12,自引:2,他引:12
目的:研究丹参素胶囊对大鼠血小板聚集性和血液流变学及血栓形成的影响。方法:以ADP为诱导剂,观察其对体外血小板聚集率的作用;采用电刺激法,测定闭塞性血栓形成的时间;用冰水刺激制备“血瘀”模型,检测主要流变学指标。结果:丹参素胶囊能明显抑制由ADP诱导的大鼠血小板体外聚集活性,延长电刺激大鼠颈总动脉后血栓形成时间,降低“血瘀”大鼠全血粘度、血浆粘度、红细胞压积、红细胞电泳时间、卡松屈服应力以及红细胞聚集指数,改善机体血液流变性。结论:丹参素胶囊能明显降低血液“浓、粘、聚、凝”状态,具有良好的活血化瘀作用。 相似文献
37.
散发内淋巴囊瘤VHL基因位点微卫星标志杂合性丢失的研究 总被引:1,自引:0,他引:1
目的 探讨散发内淋巴囊瘤发病与VHL基因异常之间的关系。方法 采用组织微切割技术和多聚酶链式反应等方法对3例散发内淋巴囊瘤肿瘤细胞VHL基因位点染色体微卫星标志的杂合性丢失进行分析。结果 3例散发内淋巴囊瘤中有2例发生VHL基因位点微卫星标志的杂合性丢失,进一步的研究证实,该两例肿瘤细胞中分别存在着VHL基因第二外显子的异常。结论 VHL基因的异常导致其功能改变不但是VHL的致病原因,而且是散发性内淋巴囊瘤发病的重要的基因遗传学基础。 相似文献
38.
对甲磺酰基苯乙烯环酮类衍生物的合成及抗炎活性 总被引:4,自引:0,他引:4
目的寻找新型高效低毒的非甾体抗炎药。方法合成对甲磺酰基苯乙烯环酮类衍生物,用二甲苯致小鼠耳肿胀模型和角叉菜胶致大鼠足跖肿胀模型评价其抗炎活性,并考察连续经口给药对大鼠胃肠道(GI)的影响。结果合成了9个新化合物(ZA1-9),结构经IR,1HNMR,MS和元素分析确证。小鼠试验表明ZA3,5-9的抗炎活性与双氯芬酸钠(DC)和罗非昔布(RC)相当(P>0.05),大鼠试验显示ZA3,7,8的抗炎活性与DC和RC相当(P>0.05), ZA6的抗炎作用显著强于DC和RC(P<0.05),ZA3,5-9对GI损伤显著小于DC (P<0.05,P<0.01),与RC相当(P>0.05)。结论对甲磺酰基苯乙烯环酮类衍生物的抗炎作用较强,GI不良反应小,值得进一步研究。 相似文献
39.
Primary melanoma of the urinary bladder is a rare neoplasm to which very strict diagnostic criteria apply. Although reports of previous cases exist, these criteria have yet to be met. We report a case of a young lady from whom a malignant melanoma of the bladder was resected. This was presumed to be primary as detailed investigation failed to find any other site from which metastases could have originated. We discuss the diagnostic criteria of this entity and stress the difficulty in conclusively demonstrating that, despite some of these criteria being met, a lesion such as this is primary in origin. This case could be the longest surviving patient with primary melanoma of the bladder, however we will never be able to prove that spontaneous regression of an undiagnosed extravesical primary malignant melanoma did not occur. 相似文献
40.
Carolyn R. Freeman B.S. M.B. FRCP Jean-Pierre Farmer M.D. FRCS José. Montes M.D. 《International journal of radiation oncology, biology, physics》1998,41(5):283-987
Developments in imaging and in neurosurgical techniques over the past decade have substantially altered the management of children with low-grade astrocytoma. Indications for surgery have become more clearly defined, and a larger proportion of children undergo complete or subtotal resection than in the past. Fewer receive adjuvant therapy, even though the options in this regard are more numerous now and theoretically likely to result in less morbidity than conventional external beam radiotherapy.
This review will address in particular the correlations between location, imaging appearance, and behavior that need to be more widely appreciated, and present recommendations regarding the management of these tumors. 相似文献