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951.
E. W. Brien Joseph M. Mirra Steven Kessler M. Suen J. K. S. Ho W. T. Yang 《Skeletal radiology》1997,26(4):246-255
It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely
does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have
been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating”
into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation
process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The
right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules
of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case
involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional,
benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas
of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from
diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there
is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma. 相似文献
952.
953.
Conventionally a confidence interval (CI) for the standardized mortality ratio is set using the conservative CI for a Poisson expectation, μ. Employing the mid-P argument we present alternative CIs that are shorter than the conventional ones. The mid-P intervals do not guarantee the nominal confidence level, but the true coverage probability is only lower than the nominal level for a few short ranges of μ. The implications for mid-P confidence intervals of various proposed definitions of two-sided tests for discrete data are discussed. 相似文献
954.
Z Z Yang 《中华结核和呼吸杂志》1992,15(2):72-4, 125
The technique of Enzyme linked immuno-electrophoresis (ELIEP) was established to detect the specific antibody against tubercle bacilli. The results of 730 cases showed that the sensitivity of this method is 97.33%, and the specificity, 97.5%. Thus this method is more sensitive than the ELISA methods which had bean published. The manipulation of ELIEP is simple, convenient, and fast, reagent stable. This method may be used in diagnosis of tuberculosis with reliability and efficiency. 相似文献
955.
956.
本文攀枝花市公共场所环境卫生质量进行了调查和分析。结果表明:空气中细菌总数超标82.7%,气湿超标71%,风速超标54.3%,噪声超标45.6%,CO2超标13.6%,CO超标9%。为改善公共场所卫生质量提出了建议。 相似文献
957.
为探讨白介素-2受体(IL-2R,即CD25)在同种异体肾移植急性细胞性排异(ACR)临床诊断的作用,着重观察移植肾发生(ACR)和无ACR时,其间质浸润细胞中IL-2R阳性细胞数的变化,及其与间质浸润的淋巴细胞的关系。作者选择同期行异体肾移植,且无并发症患者17例,采用PAP四层免疫酶标法,检测移植肾组织中间质浸润细胞中IL-2R阳性细胞数的变化。结果显示:无ACR的肾组织中,IL-2R阳性细胞仅轻度增加,当移植肾出现ACR时,IL-2R阳性细胞数的增加十分显著,并与间质浸润的CD8密切相关。作者认为IL-2R对于ACR的诊断及鉴别诊断具有一定的临床应用价值。 相似文献
958.
人皮质骨矿化基质中骨盐框架结构 总被引:2,自引:0,他引:2
目的:研究人皮质骨矿化基质中骨盐的框架结构及框架中骨微间隙。方法:应用透射电镜、场发射扫描电镜观察、电脑图像分析及能谱分析,分析无骨病成人长骨、扁骨200例骨盐分布特征。结果:骨盐框架结构由微柱、微梁、微小梁、弓状梁、致密点、隔板和骨微间隙构成。骨微间隙由洞、内衬和壁组成,洞平均直径为84.4±75.6nm,与骨小管相比有显著差异(P值<0.001),平均密度为11~17个/μm2,与骨小管之比超过10:1。骨盐分针形结晶和微颗粒结晶。结论:骨盐框架结构及骨微间隙是骨盐在人皮质骨矿化基质中的存在形式,可能与骨盐吸收、沉着有关。 相似文献
959.
采用平阳霉素作为诱变剂,对28例喉癌患者和23例正常人做外周血淋巴细胞染色体对诱变剂敏感性研究,结果显示喉癌患者的染色体总畸变率、每细胞染色单体断裂率(b/c值)和细胞畸变率分别为1.98%±0.05%,0.57%±0.35%和42.8%±12%。正常人则分别为0.94%±0.04%,0.28%±0.12%和27%±12%。经统计学处理,喉癌患者组与正常人组的差异有高度显著性。并结合实验结果探讨了染色体对致突变剂的敏感性与患喉癌风险的关系。 相似文献
960.
Atsushi Ota Nobuyasu Kano Hiroshi Kusanagi Shigetoshi Yamada Arty Garg 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):172-175
Our basic techniques for the management of difficult cases of laparoscopic cholecystectomy (LC) are presented in this article. If access to Calot's triangle cannot be gained safely, dissection should be started at the fundus or body of the gallbladder (GB), rather than the neck (fundus-first method). In cases with a short and wide cystic duct, a transfixing suture should be applied for ligation instead of clipping. EndoGIA is useful for ligating and transecting this case to avoid a subsequent stricture caused by normal method of ligation. Intraoperative cholangiography should be performed near the neck of the GB in cases in which orientation is lost during dissection. More dissection should be performed in the direction of the junction of the bile ducts after orientation is regained. In cases with GB filled with stones accompanied by severe fibrosis, part of the GB is incised to remove the stones and expose the lumen of the GB. Confluence stones can be removed by placing an incision on the GB side of the junction of the duct. The incised part is closed with suture. A cystic tube (C-tube) is placed in the common bile duct through the cystic duct for decompression. In more difficult cases in which dissection cannot be started safely at any location, the body and the fundus of the GB are excised, and a drain is placed at the neck of the GB. Dissection can be carried out from the main surgeon's or the assistant's side depending on the situation, and cooperation between the two surgeons is mandatory to achieve safe LC in difficult cases. When performing the LC, one must have a low threshold for converting to open surgery if injuries cannot be managed safely. 相似文献