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61.
���ٵ�������ͷ״������7���ٴ����� 总被引:2,自引:1,他引:1
目的 探讨乳腺导管内乳头状瘤(intraductal papillomas,IP)癌变的临床表现、生物学行为、诊断、治疗及预后。方法 对1980年1月至2001年12月间7例IP癌变病人临床资料进行回顾性分析。结果 7例IP癌变占同期113例IP的5.19%,术前均未能确诊,5例术中冰冻考虑IP癌变。结论 IP有癌变潜能,其癌变者术前确诊困难,术中冰冻对诊断治疗意义重大,应重视术后随访。 相似文献
62.
目的:探讨胰岛素样生长因子-Ⅰ(IGF-Ⅰ)对软骨细胞增殖及白细胞介素-1(IL-1)诱导软骨细胞凋亡的影响,揭示其抗损伤作用机制,为关节软骨损伤治疗提供理论依据。方法:分离培养人胚胎关节软骨细胞,采用四氮甲基唑蓝(MTT)法测定不同含量软骨细胞增殖活性的变化,利用光镜、电镜、DNA电泳及流式细胞仪测定作为凋亡检测指标。结果:IGF-Ⅰ呈剂量依赖式促软骨细胞增殖,当IGF-Ⅰ含量达50μg/L时,促软骨细胞增殖作用达最大值。IL-1组光镜、电镜下可见典型的细胞凋亡形态学改变,琼脂糖凝胶电泳示特征性的DNA梯状条带,IGF-Ⅰ处理组未见明显凋亡征象。流式细胞仪检测发现,IGF-Ⅰ处理后软骨细胞凋亡率显著降低。结论:IGF-Ⅰ能促进软骨细胞增殖,对IL-1诱导的软骨细胞凋亡具有保护作用。 相似文献
63.
Chih-Hsien Chang Kuo-Hsien Fan Te-Jung Chen Wei-Chun Hsu Mei-Ling Jan Tung-Hu Tsai Pan-Fu Kao Chieh-Fu Chen Ying-Kai Fu Te-Wei Lee 《台湾医志》2004,103(11):876-881
BACKGROUND AND PURPOSE: Fluorine-18-2-deoxy-D-glucose (18F-FDG) has been used in the clinic as a diagnostic radiotracer for monitoring many kinds of tumors, but its value for monitoring fibrosarcoma is not well established. METHODS: In this study, the uptake of 18F-FDG in a fibrosarcoma-bearing mouse model was evaluated using the high resolution positron emission tomography (PET) system microPET. Tumor cells were implanted in 3 FVB/N mice, and static microPET scanning was performed on day 1, 7, 12 and 15 after implantation. A dynamic microPET image was scanned on day 12 to determine the 18F-FDG uptake in 3 other tumor-bearing mice. Time-activity curves were plotted by drawing regions of interest in the tumor, liver, kidneys and muscles. The mice were sacrificed after dynamic microPET imaging and whole-body autoradiography (WBAR) was performed. For biodistribution study, 9 tumor-bearing mice, 3 per experimental group, were studied at 3 time points and the results were compared with the static microPET images. RESULTS: MicroPET images suggested that 18F-FDG could be used to monitor the growth of tumors 7 days after implantation. Dynamic scans of 18F-FDG uptake reached a plateau in the tumor after 20 minutes on day 12 after implantation. Both microPET and WBAR revealed evidence of tumor necrosis. The results of biodistribution and WBAR agreed with those from microPET images. CONCLUSION: MicroPET was useful for monitoring the growth of fibrosarcoma and determination of the maximal uptake time point of 18F-FDG in tumors in this tumor-bearing mouse model. 相似文献
64.
Ping L. Zhang Sayeed K. Malek Jeffery W. Prichard Fan Lin Taher M. Yahya Michael S. Schwartzman Ruth P. Latsha Evan R. Norfolk Thomas M. Blasick Mingyue Lun Robert E. Brown James E. Hartle Santosh Potdar 《American journal of transplantation》2005,5(3):604-607
Campath-1H has been used successfully for induction and has resulted in a low rate of acute cellular rejection (ACR) in renal transplantation in combination with various postoperative immunosuppression regimens. This study was undertaken to investigate the extent of monocyte involvement in ACR, with or without Campath-1H induction. We found that monocytes represented the majority of inflammatory cells in grades Ib or higher ACR, but not with Ia type of ACR, regardless of the status of Campath-1H induction. Cases of ACR, following Campath-1H induction, appear to demonstrate a 'pure form' of monocytic ACR, whereas monocytes were mixed with many other types of inflammatory cells in the cases of ACR in the absence of Campath-1H induction. In addition with Campath-1H induction, the cases of monocyte-predominant ACR were found to uniformly exhibit a good response to corticosteroid treatment. We conclude that monocyte-predominate ACR may represent a severe form of rejection, with or without Campath-1H treatment. 相似文献
65.
We present a proof that the mean open (and closed) times of the individual channels in a multichannel record can be found in a model-independent fashion. As the results are model independent, they can be derived by assuming the simplest model for all the channels, namely that they all have the basic CLOSED in equilibrium with OPEN scheme. In particular, the method can be applied to patches where the channel population is heterogenous with respect to open probability. Multichannel simulations are performed to test the limits of applicability of this method to restricted amounts of data. One conclusion is that increasing the number of channels does not substantially reduce the errors in estimating the mean times, in spite of the 'increased information' present. We also prove the general applicability of the algorithm of Fenwick et al. (1982) in estimating the mean times without knowledge of the number of channels present, and discuss its limitations. An illustration using experimental data is also given. 相似文献
66.
采用原子吸收光谱法测定了30例糖尿病患者血清锌、镁、钙的含量,并与30例正常人相比较。结果表明,其锌和镁较正常人为低(P<0.05),但钙与正常人无显著性差别。另外,本文还对锌、镁与糖尿病的关系进行了探讨。 相似文献
67.
68.
S. T. Fan Q. S. Wang C. M. Lo K. W. Tam Yu E. C. S. Lai J. Wong 《ANZ journal of surgery》1994,64(11):759-762
Impaired hepatic function is a major contributory factor to the high incidence of postoperative morbidity and mortality in patients with malignant biliary obstruction. Dynamic hepatic function tests such as indocyanine green (ICG) retention and aminopyrine breath tests were evaluated in such patients to define whether they were clinically useful for prediction of postoperative morbidity and mortality. Forty-four patients with malignant biliary obstruction undergoing surgery for relief of obstructive jaundice were recruited into the study. Indocyanine green retention and aminopyrine breath tests were carried out in all patients pre-operatively and repeated in 36 patients postoperatively. The ICG retention was abnormal in all patients before surgery and there was significant improvement 2 weeks after surgery (32.8 ± 2.5%vs 18.3 ± 2.8%, P= 0.001). The change in ICG retention levels correlated with the serum bilirubin levels but the pre-operative ICG retention value could not predict postoperative morbidity and mortality. The aminopyrine breath test was abnormal in all but one patient. It correlated with pre-operative prothrombin time of the patients before surgery but it did not improve significantly after surgery and was not predictive of postoperative outcome. It is concluded that both ICG retention and aminopyrine breath tests have limited clinical value in the pre-operative evaluation of patients with malignant biliary obstruction. 相似文献
69.
脆性X综合征中不稳定的DNA序列和异常甲基化研究 总被引:1,自引:0,他引:1
采用PCR结合序列胶分析的方法,对82条正常中国人X染色体FRAXA位点(CGG)n重复序列拷贝数的多态性进行了测定,其范围为21~31,高峰为27。并通过Southern杂交分析了来自6个Fra(X)家系的15名成员(CGG)n的拷贝数与该重复序列上游CpG岛的甲基化状态。Fra(X)患者(CGG)n大量扩增并伴随CpG岛异常甲基化。Fra(X)携带者女性(CGG)n扩增较少,有嵌合现象。其子代或产生更大扩增,或保持原来状态,呈动态突变遗传特征。 相似文献
70.
目的研究正常人静态及运动状态下死腔/潮气(VD/VT)估测值和实测值的关系.方法23名受试者行心肺运动试验,同步实时测定摄氧量和二氧化碳排出量,分别在运动前及运动高峰时抽取动脉血,根据Bohr的公式,得出VD/VT实测值,同时再用呼气末CO2分压(PetCO2)代替PaCO2,计算VD/VT,得出VD/VT估测值.结果根据病史、体检、肺功能和运动前后的心电图判断23名受试者均为正常受试者.静态时的VD/VT估测值和VD/VT实测值分别为0.359±0.109和0.354±O.106,两者无显著性差异(P=0.710),相关分析显示两者高度相关(r=0.911,P<0.001).运动高峰时的VD/VT估测值和VD/VT实测值分别为0.234±0.070和0.248±0.094,两者无显著性差异(P=0.748),相关分析表明两者显著相关(r=0.783,P<0.001).与静态时比较,运动时估测和实测VD/VT均明显下降.结论对于正常成人,无论是在静态或最大运动状态下,可用无创方法计算VD/VT代替VD/VT实测值. 相似文献