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排序方式: 共有433条查询结果,搜索用时 15 毫秒
1.
Malathi MSinthia PMadhanlal UMahendrakan KNalini M 《Asian Pacific journal of cancer prevention》2022,23(3):905-910
Objective: Lung cancer is one of the unsafe diseases for human which reduces the patient life time. Generally, most of the lung cancers are identified after it has been spread into the lung parts and moreover it is difficult to find the lung cancer at the early stage. It requires radiologist and special doctors to find the tumoral tissue of the lung cancer. For this reason, the recommended work helps to segment the tumoral tissue of CT lung image in an effective way. Methods: The research work uses hybrid segmentation technique to separate the lung cancer cells to diagnose the lung tumour. It is a technique which combines active contour along with Fuzzy c means to diagnose the tumoral tissue. Further the segmented portion was trained by Convolutional Neural Network (CNN) in order to classify the segmented region as normal or abnormal. Results: The evaluation of the proposed method was done by analyzing the results of test image with the ground truth image. Finally, the results of the implemented technique provided good accuracy, Peak signal to noise ratio (PSNR), Mean Square Error (MSE) value. In future the other techniques can be utilized to improve the details before segmentation. The proposed work provides 96.67 % accuracy. Conclusion: Hybrid segmentation technique involves several steps like preprocessing, binarization, thresholding, segmentation and feature extraction using GLCM. 相似文献
2.
实验性脑出血血肿灶周脑血流量变化与细胞凋亡的相关性研究 总被引:1,自引:1,他引:1
目的 探讨脑出血 (ICH)后血肿灶周脑血流量变化与细胞凋亡的相互关系。方法 健康家犬 2 7只 ,随机分为对照组和ICH组 (3h、6h、12h、2 4h、4 8h、72h、7d和 15d)。ICH模型采用立体定向自体血额叶皮层注射法建立。应用磁共振灌注加权成像 (PWI)和流式细胞术 (FCM ) ,动态检测不同时间点血肿灶周相对脑血流量 (rCBF)与凋亡峰 /凋亡率的变化。结果 ①脑血流量变化 :PWI显示血肿灶周 12h之内rCBF明显降低 ,呈低灌注状态 ,12~ 2 4hrCBF回升 ,出现血流再灌注 ,或高灌注现象 ,4 8h以后接近对侧 ,呈持续稍低灌注状态。②细胞凋亡变化 :FCM显示血肿灶周区凋亡峰 /凋亡率 6h开始出现 ,72h最高 ,7d下降。③血肿灶周凋亡峰值与凋亡率的变化呈正相关 (r =0 84 6 ,P <0 0 5 )。结论 ICH后血肿灶周脑血流量呈中 -轻度降低 ,细胞凋亡主要存在于血肿灶周区 ,72h是血肿灶周细胞凋亡的时间窗。 相似文献
3.
目的磁共振成像(magnetic resonance imaging,MRI)对脑组织有较好的成像效果,但噪声、偏移场和部分容积效应(partial volume effect,PVE)的存在,使得全自动分割MRI图像面临一定的困难。模糊C均值(fuzzy C-means,FCM)聚类算法在脑组织分割中得到较广泛研究。本文以存在噪声和偏移场影响的脑MRI图像分割为应用背景,研究了大量相关方法,探讨FCM算法分割脑部图像的改进思想。方法本文主要研究了9种FCM算法的理论基础,并通过脑组织分割实验对各种算法进行了分析。结果比较了不同算法的优劣,给出各类算法直观及定量评价结果。结论偏移场和噪声对脑磁共振图像组织分类质量有明显影响。其中几种方法可以减弱这些不利影响,但由于难以选择合适的参数,其分类效果并不理想。如何合理利用空间信息在未来仍有较大研究价值。 相似文献
4.
目的:通过检测CyclinD1和CDC25A在胆囊癌中的表达,探讨其在胆囊癌发生发展中的作用及其机制,为胆囊癌诊断和治疗寻找新的靶点。方法采用流式细胞术检测44例胆囊癌和35例慢性胆囊炎黏膜组织的CyclinD1、CDC25A蛋白的表达,其中蛋白的表达量用平均荧光强度(均道值)表示。结果胆囊癌组织、慢性胆囊炎黏膜组织中CyclinD1蛋白表达分别为(531.153±28.823)、(496.462±37.191),胆囊癌组织的CyclinD1蛋白表达高于正常组织;胆囊癌组织、慢性胆囊炎黏膜组织中CDC25A蛋白表达分别为(535.029±35.647)、(496.267±41.345),胆囊癌组织的CDC25A蛋白表达高于慢性炎症组织。结论 CyclinD1和CDC25A蛋白在胆囊癌组织中均高表达。这两种基因和蛋白表达的改变可能是引起胆囊癌发生发展的分子机制之一。 相似文献
5.
目的:测定冷藏(4℃)保存48 h后血小板膜糖蛋白GPⅠbα末端糖基脱落情况。方法分别以一定浓度梯度的FITC-sWGA、FITC-RCA-1、FITC-ECA标记血小板,应用流式细胞仪检测,确定最佳工作浓度。检测冷藏保存48 h后血小板GPⅠbα末端唾液酸基及次末端半乳糖基脱落情况。结果 FITC-sWGA、FITC-RCA-1、FITC-ECA工作浓度分别为2μg/ml、2μg/ml、30μg/ml时标记效果好。冷藏保存48 h后GPⅠbα末端唾液酸基及次末端半乳糖基脱落较22℃常规保存明显增加,分别增至(156±18)%及(123±13)%,差异有统计学意义(P<0.01)。结论冷藏保存48 h可致血小板膜糖蛋白GPⅠbα末端糖基脱落增加。 相似文献
6.
目的从重组柞蚕抗菌肽AD毕赤酵母发酵液中分离纯化出抗菌肽纯品,并对其进行纯度、分子量和抗菌作用的鉴定。方法用离子交换和疏水层析法对发酵液中的重组柞蚕抗菌肽AD进行分离纯化,用高效液相色谱法分析产物的纯度,再用基质辅助激光解析—飞行时间质谱仪对产物进行分子量鉴定,并结合传统微量肉汤稀释法和流式细胞术分析重组柞蚕抗菌肽AD纯品对E.coli敏感株及耐药株的抗菌作用。结果重组柞蚕抗菌肽AD经离子交换和疏水层析纯化后的纯度达到98.40%,分子量为4068.15Da,与所设计的重组柞蚕抗菌肽AD大小相近。所纯化出的重组柞蚕抗菌肽AD对E.coli的敏感株ATCC25922和产β-内酰胺酶耐药株株ATCC35218的抗菌作用均为MIC 8μg/m L,而头孢他啶和氨苄西林对耐药株ATCC35218的MIC的值分别为8μg/m L和>32μg/m L。结论成功纯化分离出具有自主知识产权的重组柞蚕抗菌肽AD,其对E.coli敏感株和耐药株具有相同的抗菌效果。 相似文献
7.
Yun Wang Liankang Sun Yumei Luo Shuixiang He 《Pathology, research and practice》2019,215(5):1054-1060
Pancreatic cancer (PC) is one of the common malignant tumors in digestive tract with a high fatality rate. The oncogenic role of lysine-specific demethylase1 (LSD1/KDM1?A) has been well recognized in PC. While, the role of its homolog LSD2 (KDM1B) in regulating PC progression is poorly understood. In this study, we attempted to evaluate the functional role of KDM1B in PC cells. The expression of KDM1B was detected by immunohistochemistry and immunoblotting in PC tissues and cells. Lentivirus-mediated shRNA was applied to silence KDM1B in PANC-1 and SW1990 cells. Cell proliferation was measured by MTT and Celigo assay. Cell apoptosis was determined by both Caspase-Glo®3/7 assay and Flow cytometry. Intracellular signaling molecules were detected using a PathScan intracellular signaling array kit. In this study, we found KDM1B was highly expressed in PC tissues compared to paracancerous tissues. Moreover, elevated expression of KDM1B was detected in PC cell lines (BxPC-3, CFPAC-1, PANC-1 and SW1990) as compared with a normal human pancreatic duct epithelial cell line (HPDE6-C7). Further investigations revealed that KDM1B knockdown significantly inhibited PC cell proliferation. Furthermore, the apoptosis of PANC-1 and SW1990 cells was significantly increased after KDM1B knockdown. Notably, the activations of p-ERK1/2, p-Smad2, p-p53, cleaved PARP, cleaved Caspase-3, cleaved Caspase-7, p-eIF2a and Survivin were promoted by KDM1B knockdown, while IkBa was suppressed. Taken together, our findings provided new insights into the critical and multifaceted roles of KDM1B in the regulation of cell proliferation and apoptosis, and offered a potentially novel target in preventing the progression of PC. 相似文献
8.
Bruno M.L. Rocha Gonçalo J.L. Cunha Luiz F. Menezes Falcão 《Journal of the American College of Cardiology》2018,71(7):782-793
Heart failure (HF) is highlighted by its burdening symptom-limited exercise capacity and recurrent hospitalizations. Despite substantial advances regarding disease-modifying drugs in HF with reduced ejection fraction, additional therapeutic strategies to improve quality of life are invaluable. Currently, iron deficiency (ID) is overwhelmingly recognized in over 30% to 50% of patients with stable chronic HF, which worsens prognosis. The established pathophysiological mechanisms of progressive HF may be intertwined with increasing myocardial iron scarcity, wherein one begets the other. Most importantly, ID constitutes a novel target for symptom relief in carefully selected patients. In this regard, intravenous iron may be a safe and efficacious intervention, potentially reducing HF hospitalizations. We discuss the evidence and gaps in knowledge concerning iron therapy in HF and propose a practical, comprehensive, clinically oriented algorithm for timely adequate iron replenishment in different clinical scenarios. Finally, we further debate imperative decision-making before intervention and the drawbacks of such a strategy. 相似文献
9.
10.
多药耐药基因、CD34~+的表达对急性髓细胞性白血病化疗效果的影响 总被引:1,自引:0,他引:1
目的探讨白血病多药耐药(MDR)基因表达对化疗的影响。方法应用FITC单克隆CD34荧光抗体对30例急性髓细胞性白血病(AML)患者行流式细胞术检测CD34+的表达;RT-PCR(逆转录/多聚酶链式反应)半定量法检测耐药基因的表达;并进行了细胞遗传学分析。结果 30例初诊的白血病患者,24例MDR-1表达阳性中,化疗后达到缓解(CR)者13例(54.2%),而未缓解及部分缓解者11例;6例MDR-1未表达者,化疗后只有1例(16.7%)未达到CR。30例病人流式细胞术检测显示,CR组18例中有15例CD34+细胞率〈2.1%,未CR组12例中有9例CD34+细胞率〉5.7%。结论多药耐药基因表达影响AML的预后效果,CD34+细胞也可作为AML的预后指标。 相似文献