目的探讨表观扩散系数(apparent diffusion coefficient,ADC)术前无创评估直肠腺瘤瘤体是否癌变的可行性。方法回顾性分析71例已经过手术病理证实的直肠病变患者(直肠腺瘤患者21例、直肠腺瘤并癌变患者14例及直肠腺癌患者36例)的MRI平扫...目的探讨表观扩散系数(apparent diffusion coefficient,ADC)术前无创评估直肠腺瘤瘤体是否癌变的可行性。方法回顾性分析71例已经过手术病理证实的直肠病变患者(直肠腺瘤患者21例、直肠腺瘤并癌变患者14例及直肠腺癌患者36例)的MRI平扫及DWI检查,ADC值由b值为0 s/mm^(2)和1000s/mm^(2)的DWI检查计算所得,测量肿瘤的平均ADC值及最小ADC值,根据直肠腺瘤、直肠腺瘤癌变及直肠腺癌进行分组,采用独立样本t检验分别比较分析。结果直肠腺瘤及腺瘤癌变分组的最小ADC值(1.126±0.134比1.015±0.107,P=0.015)、直肠腺瘤及腺癌分组的平均A D C值(1.277±0.099比1.026±0.096,P=0.000)及最小A D C值(1.126±0.134比0.995±0.087,P=0.000)、直肠腺瘤癌变及腺癌分组的平均ADC值(1.207±0.116比1.026±0.096,P=0.000)及最小ADC值(1.015±0.107比0.995±0.087,P=0.047)具有统计学学意义,仅直肠腺瘤及腺瘤癌变分组的平均ADC值(1.277±0.099比1.207±0.116,P=0.064)无统计学意义,最小ADC值在评估直肠腺瘤瘤体是否癌变中的作用优于平均ADC值。结论ADC值可在一定程度上对直肠腺瘤是否癌变做出较好预测。展开更多
目的探讨双能量CT线性融合优化对比技术对肝脏增强图像质量影响,获得线性融合方式在肝脏图像质量应用中最佳加权因子。方法收集50例肝脏双能量CT增强扫描患者线性融合图像数据进行分析测量,比较门静脉期加权因子0.1~0.9融合图像的噪声(...目的探讨双能量CT线性融合优化对比技术对肝脏增强图像质量影响,获得线性融合方式在肝脏图像质量应用中最佳加权因子。方法收集50例肝脏双能量CT增强扫描患者线性融合图像数据进行分析测量,比较门静脉期加权因子0.1~0.9融合图像的噪声(SD)、信噪比(Signal to Noise Ratio,SNR)、对比噪声比(Contrast to Noise Ratio,CNR),并对各组图像质量进行主观评分。结果在加权因子为0.4~0.6的混合能量图像中图像SD较低。加权因子为0.5~0.7时图像的SNR较高,加权因子为0.6~0.8时图像的CNR较高,图像CT值在0.1~0.9加权因子中呈递增趋势。加权因子0.5与0.6、0.6与0.7组SD、SNR、CNR、CT值组间比较无统计学意义,0.5与0.7组组间比较CT值有统计学意义。加权因子0.5、0.6、0.7主观图像质量评价评分较高,0.7组最高,0.6组次之。结论双能肝脏增强扫描中加权因子为0.6、0.7时均可获取具有相对较低的SD和较高的SNR、CNR、CT值图像,对于观察肝脏乏血供病灶时选择加权因子0.7融合图像最佳,当在肝损害、脂肪肝背景下时,选用较低SD的加权因子0.6时图像观察较佳。展开更多
Background Many studies have suggested that the imbalance of angiogenic factor and anti-angiogenic factor expression contributes significantly to the development of choroidal neovascularization （CNV）, and ultrasound...Background Many studies have suggested that the imbalance of angiogenic factor and anti-angiogenic factor expression contributes significantly to the development of choroidal neovascularization （CNV）, and ultrasound microbubble combination system can increase the gene transfection efficiency successfully. This study was designed to investigate whether ultrasound-mediated microbubble destruction could effectively deliver therapeutic plasmid into the retina of rat, and whether gene transfer of pigment epithelium-derived factor （PEDF） could inhibit CNV.Methods Human retinal pigment epithelial cells were isolated and treated either with ultrasound or plasmid alone, or with a combination of plasmid, ultrasound and microbubbles to approach feasibility of microbubble-enhanced ultrasound enhance PEDFgene expression; For in vivo animal studies, CNV was induced by argon lasgon laser in rats. These rats were randomly assigned to five groups and were treated by infusing microbubbles attached with the naked plasmid DNA of PEDF into the vitreous of rats followed by immediate ultrasound exposure （intravitreal injection）; infusing liposomes with the naked plasmid DNA of PEDF into the vitreous （lipofectamine ＋ PEDF）; infusing microbubbles attached with PEDF into the orbit of rats with ultrasound irradiation immediately （retrobular injection）; infusing microbubbles attached with PEDF into the femoral vein of rats with exposed to ultrasound immediately （vein injection）. The CNV rats without any treatment served as control. Rats were sacrificed and eyes were enucleated at 7, 14, and 28 days after treatment. Gene and protein expression of PEDF was detected by quantitative real-time RT-PCR, Western blotting and immunofluorescence staining, respectively. The effect of PEDF gene transfer on CNV was examined by fluorescein fundus angiography.Results In vitro cell experiments showed that microbubbles with ultrasound irradiation could significantly enhance PEDF delivery as compared with microbubbles or ultrasound alone. In the rat CNV model, transfection efficiency mediated by ultrasound/microbubbles was significantly higher than that by lipofectamine-mediated gene transfer at 28 days after treatment. The study also showed that with the administration of ultrasound-mediated microbubbles destruction, the CNV of rats was inhibited effectively. Conclusions Ultrasound-microbubble technique could increase PEDF gene transfer into rats＇ retina and chorioid, in association with a significant inhibition of the development of CNV, suggesting that this noninvasive gene transfer method may provide a useful tool for clinical gene therapy.展开更多
文摘目的探讨表观扩散系数(apparent diffusion coefficient,ADC)术前无创评估直肠腺瘤瘤体是否癌变的可行性。方法回顾性分析71例已经过手术病理证实的直肠病变患者(直肠腺瘤患者21例、直肠腺瘤并癌变患者14例及直肠腺癌患者36例)的MRI平扫及DWI检查,ADC值由b值为0 s/mm^(2)和1000s/mm^(2)的DWI检查计算所得,测量肿瘤的平均ADC值及最小ADC值,根据直肠腺瘤、直肠腺瘤癌变及直肠腺癌进行分组,采用独立样本t检验分别比较分析。结果直肠腺瘤及腺瘤癌变分组的最小ADC值(1.126±0.134比1.015±0.107,P=0.015)、直肠腺瘤及腺癌分组的平均A D C值(1.277±0.099比1.026±0.096,P=0.000)及最小A D C值(1.126±0.134比0.995±0.087,P=0.000)、直肠腺瘤癌变及腺癌分组的平均ADC值(1.207±0.116比1.026±0.096,P=0.000)及最小ADC值(1.015±0.107比0.995±0.087,P=0.047)具有统计学学意义,仅直肠腺瘤及腺瘤癌变分组的平均ADC值(1.277±0.099比1.207±0.116,P=0.064)无统计学意义,最小ADC值在评估直肠腺瘤瘤体是否癌变中的作用优于平均ADC值。结论ADC值可在一定程度上对直肠腺瘤是否癌变做出较好预测。
文摘目的探讨双能量CT线性融合优化对比技术对肝脏增强图像质量影响,获得线性融合方式在肝脏图像质量应用中最佳加权因子。方法收集50例肝脏双能量CT增强扫描患者线性融合图像数据进行分析测量,比较门静脉期加权因子0.1~0.9融合图像的噪声(SD)、信噪比(Signal to Noise Ratio,SNR)、对比噪声比(Contrast to Noise Ratio,CNR),并对各组图像质量进行主观评分。结果在加权因子为0.4~0.6的混合能量图像中图像SD较低。加权因子为0.5~0.7时图像的SNR较高,加权因子为0.6~0.8时图像的CNR较高,图像CT值在0.1~0.9加权因子中呈递增趋势。加权因子0.5与0.6、0.6与0.7组SD、SNR、CNR、CT值组间比较无统计学意义,0.5与0.7组组间比较CT值有统计学意义。加权因子0.5、0.6、0.7主观图像质量评价评分较高,0.7组最高,0.6组次之。结论双能肝脏增强扫描中加权因子为0.6、0.7时均可获取具有相对较低的SD和较高的SNR、CNR、CT值图像,对于观察肝脏乏血供病灶时选择加权因子0.7融合图像最佳,当在肝损害、脂肪肝背景下时,选用较低SD的加权因子0.6时图像观察较佳。
文摘目的:研究与比较肾肉瘤样癌(Sarcomatoid renal cell carcinoma,SRCC)与肾透明细胞癌(Clear cell renal cell carcinoma,CCRCC)在同步转移方式上的不同,以利于临床鉴别诊断。方法 :同步转移是指诊断时出现的转移,回顾性分析直径>6 cm的45例SRCC与143例CCRCC的病例及影像学资料,所有病例均行术前腹部增强CT检查,采用χ~2检验或Fisher确切概率法对两者同步转移部位进行分析。结果:16例SRCC和10例CCRCC出现同步转移(16/45 vs 10/143),11例SRCC和1例CCRCC出现同步淋巴结转移(11/45 vs 1/143),6例SRCC与6例CCRCC出现肺转移(6/45 vs 6/143),6例SRCC和1例CCRCC出现同步多部位转移(6/45 vs 1/143),差异均具有统计学意义(P值依次为0.000,0.000,0.039,0.003)。然而,将以上3个特征纳入Logistic回归分析后,仅同步淋巴结转移有统计学意义(P=0.030)。结论:同步淋巴结转移在SRCC中比CCRCC中更常见,有助于鉴别SRCC与CCRCC。
基金This study was supported by grants from the Key Program of National Natural Science Foundation of China （No. 30872826）, the National High Technology Research and Development Program of China （No. 2006501）, the Chongqing Municipal Health Bureau （No. 05-2-120） and the Project of Chongqing Key Laboratory of Ophthalmology （CSTC, No. 2008CA5003）.
文摘Background Many studies have suggested that the imbalance of angiogenic factor and anti-angiogenic factor expression contributes significantly to the development of choroidal neovascularization （CNV）, and ultrasound microbubble combination system can increase the gene transfection efficiency successfully. This study was designed to investigate whether ultrasound-mediated microbubble destruction could effectively deliver therapeutic plasmid into the retina of rat, and whether gene transfer of pigment epithelium-derived factor （PEDF） could inhibit CNV.Methods Human retinal pigment epithelial cells were isolated and treated either with ultrasound or plasmid alone, or with a combination of plasmid, ultrasound and microbubbles to approach feasibility of microbubble-enhanced ultrasound enhance PEDFgene expression; For in vivo animal studies, CNV was induced by argon lasgon laser in rats. These rats were randomly assigned to five groups and were treated by infusing microbubbles attached with the naked plasmid DNA of PEDF into the vitreous of rats followed by immediate ultrasound exposure （intravitreal injection）; infusing liposomes with the naked plasmid DNA of PEDF into the vitreous （lipofectamine ＋ PEDF）; infusing microbubbles attached with PEDF into the orbit of rats with ultrasound irradiation immediately （retrobular injection）; infusing microbubbles attached with PEDF into the femoral vein of rats with exposed to ultrasound immediately （vein injection）. The CNV rats without any treatment served as control. Rats were sacrificed and eyes were enucleated at 7, 14, and 28 days after treatment. Gene and protein expression of PEDF was detected by quantitative real-time RT-PCR, Western blotting and immunofluorescence staining, respectively. The effect of PEDF gene transfer on CNV was examined by fluorescein fundus angiography.Results In vitro cell experiments showed that microbubbles with ultrasound irradiation could significantly enhance PEDF delivery as compared with microbubbles or ultrasound alone. In the rat CNV model, transfection efficiency mediated by ultrasound/microbubbles was significantly higher than that by lipofectamine-mediated gene transfer at 28 days after treatment. The study also showed that with the administration of ultrasound-mediated microbubbles destruction, the CNV of rats was inhibited effectively. Conclusions Ultrasound-microbubble technique could increase PEDF gene transfer into rats＇ retina and chorioid, in association with a significant inhibition of the development of CNV, suggesting that this noninvasive gene transfer method may provide a useful tool for clinical gene therapy.
