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排序方式: 共有722条查询结果,搜索用时 31 毫秒
51.
《Saudi Journal of Biological Sciences》2020,27(3):805-811
In order to assess the efficacy of 18F-FDG PET/CT-based diagnostic model in diagnosing colorectal cancer (CRC) lymph node metastasis (LNM), the 18F-FDG PET/CT medical records of CRC patients were acquired, and the CRC regional LNM diagnostic model was constructed through the combination of image and grain factors of 18F-FDG PET/CT. The specific analysis methods include univariate analysis, multivariate analysis, ROC curve analysis, and statistical analysis. The research results showed statistical differences in TNM staging, intestinal obstructions, tumor infiltration, regional lymph node (LN) SUVmax, regional LN minimum dimension, and remote metastasis between the CRC patients in the LNM positive group and the LNM negative group. Through the comparisons between the diagnostic model proposed in the research and other diagnostic methods, it was found that the AUC (95%CI) and sensitivity of the proposed diagnostic model were the highest, the comprehensive diagnostic efficacy of the diagnostic model was optimal. Therefore, it was concluded that the diagnostic model was of significant application values, which provided the basis for subsequent clinical diagnosis of CRC. 相似文献
52.
Ning Xu Gen-Yi Qu Yu-Peng Wu Yun-Zhi Lin Dong-Ning Chen Xiao-Dong Li Shao-Hao Chen Jin-Bei Huang Qing-Shui Zheng Xue-Yi Xue Yong Wei 《Journal of cellular biochemistry》2020,121(1):231-243
The significance of actin-related protein 2/3 complex subunit 4 (ARPC4) expression in bladder cancer, and its potential role in the invasion and migration of bladder cancer cells, has yet to be determined. This study was to identify the correlation between ARPC4 and lymph node metastasis, and to determine the role of ARPC4 in the invasive migration of T24 bladder cancer cells. One hundred and ninety-eight bladder cancer tissues and 40 normal bladder and lymph node tissues were examined. Tissue microarrays were constructed and subjected to immunohistochemical stating for ARPC4. Multiple logistic analysis was used to determine risk factors associated with bladder cancer metastasis. ARPC4 expression in T24 bladder cancer cells was suppressed using small interfering RNA and changes in protein levels were determined by Western blot analysis. The proliferation of bladder cancer cells after knocking down of ARPC4 was determined by cell counting kit-8. The effects of ARPC4 knockdown on T24 cell invasion and migration was determined using transwell and wound healing assays. Immunofluorescence analysis was performed to examine changes in pseudopodia formation and actin cytoskeleton structure. The expression of ARPC4 was elevated in bladder cancer tissues than normal tissues (84.3% vs 27.5%, P < 0.001). The multivariate logistic analysis demonstrated that the level of ARPC4, as a risk factor, was correlated with lymphatic metastasis (P < 0.05). ARPC4 knockdown attenuated proliferation, migration, invasion, and pseudopodia formation in T24 cells. ARPC4 expression, as a risk factor, is associated with lymphatic metastasis and is upregulated in bladder cancer tissues in comparison with normal tissues. Inhibition of ARPC4 expression significantly attenuates the proliferation, migration, and invasion of bladder cancer cell, possibly due to defects in pseudopodia formation. 相似文献
53.
摘要 目的:探讨动态对比增强磁共振(DCE-MRI)联合弥散加权成像(DWI)诊断直肠癌术前T、N分期和系膜淋巴结良恶性的价值。方法:收集2017年2月至2019年10月中国医科大学附属本溪中心医院和中国医科大学附属盛京医院接诊的80例直肠癌患者,均进行常规核磁共振成像(MRI)、DCE-MRI、DWI扫描,获得DCE-MRI、DWI定量参数[转运常数(K trans )、细胞外血管外空间的体积分数(V e )、速率常数(K ep )、表观扩散系数(ADC)],比较不同T、N分期、不同性质系膜淋巴结DCE-MRI、DWI参数,及其对T、N分期和系膜淋巴结性质的诊断效能。结果:直肠癌癌灶K trans 、 K ep 、V e 高于正常肠壁,ADC低于正常肠壁(P<0.05)。TNM分期为TⅢ~Ⅳ期的患者K trans 、 K ep 、V e 高于TⅠ~Ⅱ期,ADC低于TⅠ~Ⅱ期(P<0.05);TNM分期为N1期的患者K trans 、K ep 、V e 高于N0期,ADC低于N0期(P<0.05)。联合诊断的灵敏度、特异度、阳性预测值、阴性预测值较高。结论:DCE-MRI联合DWI对直肠癌术前T、N分期、系膜淋巴结性质诊断价值较高。 相似文献
54.
抗原物质引起滤泡的形成:一次投入与多次投入的比较 总被引:2,自引:0,他引:2
实验以不同方式投入抗原物质,即一次投入与分次投入,并观察了新产生滤泡数,维持的滤泡数,实验用小鼠24 只, 于足底注入铝和钥孔 血蓝素附合物(AKLH), 分一次注入与三次注入组; 三次注入组又分间隔5 日及间隔二周注入。注入后第3 周与第12 周分别取出腘淋巴结,应用免疫组化法,第三周末观察可见一次投入产生的滤泡多, 而第十二周发现分次投入维持的滤泡数多。可见反应性滤泡的形成, 不仅与刺激物的性状和投入量有关, 而且与投入的方法有关 相似文献
55.
A data base was generated for quantifying effects of thermal time (degree-days) on the appearance of new leaves, the expansion of such leaves to maximum area, their death, the appearance of new internodes below the node associated with such leaves, and the extension of these internodes to maximum length. The data base for a list of crop (agronomic and horticultural), weed, and native Tallgrass Prairie plants has been summarized, with equations for the above events as a function of degree days, with appropriate base temperatures and maximum cut-off temperatures, in a Java applet which is available at a website with the URL . Associated graphical plots such as shown in this paper are also given. Branching behavior was accounted for. These events predict the effect of thermal time on leaf age and its height in the plant canopy, both important factors needed for upscaling functions for leaf behavior to those for behavior of the plant canopy. The data base is evolving to include coefficients for other species. Coefficients are used to predict the leaf area index of the canopy, which is important for predicting evapotranspiration from the crop and the protection of the soil from erosion. 相似文献
56.
57.
The sequences of the internal transcribed spacer (ITS) region of 18S–26S nrDNA for a sample of 16 taxa from theInuleae s. str. and two outgroup taxa are analysed cladistically with PAUP. A consensus tree of the four most parsimonious cladograms is presented. Three different tests of cladogram stability are conducted (Bremer support, parsimony jackknifing and bootstrapping); all tests indicate a high degree of support for the basal nodes of the tree. The ITS phylogeny of the tribe is compared with previous hypotheses based on morphological data. The position ofAnisopappus as sister group to the rest of the tribe is supported by the molecular data, but the proposed subdivision ofInuleae s. str. into a paleate grade group and an epaleate clade is not. The interpretation of the character evolution of, e.g. receptacular paleae and pappus features within the tribe is discussed. 相似文献
58.
A protocol is presented for micropropagation of an economically important timber-yielding forest tree, Dalbergia sissoo Roxb. (Sissoo). Multiple shoots were induced from cotyledonary nodes derived from 1-week-old axenic seedlings on Murashige
and Skoog's medium containing either N
6-benzyladenine (BA), kinetin (Kn), isopentenyladenine (2iP) or thidiazuron (TDZ), with BA being the most effective growth
regulator. High-frequency shoot proliferation (99%) and maximum number of shoots per explant (7.9 shoots) were recorded with
BA at an optimum level of 8.9 μM. Concentrations of all cytokinins tested above the optimum level markedly reduced the frequency of shoot proliferation. A
proliferating shoot culture was established by repeatedly subculturing the original cotyledonary node on shoot multiplication
medium after each harvest of the newly formed shoots. Primary shoots were multiplied as nodal explants, and from each stem
node 2 or 3 shoots developed. Thus, 60–70 shoots were obtained in 3 months from a single cotyledonary node. About 91% of the
shoots developed roots following transfer to half-strength MS medium containing a combination of 5.7 μM indole-3-acetic acid, 4.9 μM indole-3-butyric acid and 5.3 μM indole-3-propionic acid. Eighty percent of the plantlets were successfully acclimatized and established in soil.
Received: 1 October 1997 / Revision received: 31 March 1998 / Accepted: 7 April 1998 相似文献
59.
Carlos Eduardo Pereira Corbett Márcia Dalastra Laurenti 《Parasitology international》1998,47(4):310-310
To study the route of migration of Leishmania (Leishmania) chagasi to the viscera from the subcutaneous inoculation site, ultrastructural studies were carried out. These studies on popliteal draining lymph nodes of hamsters inoculated with 107 promastigotes of Leishmania (Leishmania) chagasi in the hind footpad were carried out. Parasites were detected in lymph nodes just 2 h after inoculation. Parasites were either preserved or degenerated in macrophages. In 24 h signs of binary division of the parasites were found in macrophages. This fact suggests that the parasites migrate from skin to the lymph node early in the infection within phagocytes and proliferate in lymph nodes before dissemination to the viscera. 相似文献
60.
《Reports of Practical Oncology and Radiotherapy》2018,23(6):495-502
Cervical cancer is the fourth most common cancer in women, and seventh overall. This disease represents a medical, economic and social burden. In early FIGO stage patients (IA, IB1 and IIA1), nodal involvement is the most important prognostic factor. Imaging evaluation of nodal metastasis is of limited value. In order to determine lymph node involvement, allow loco-regional control of the disease, define the need for adjuvant radiotherapy and improve survival, standard surgery for early disease is radical hysterectomy with systematic pelvic lymphadenectomy. However, this surgical treatment has risks and complications: longer operative time, larger blood loss, neurovascular or ureteral injury, lower-limb lymphedema, symptomatic lymphocysts, hydronephrosis. A method that allows to define the presence of regional metastasis with less morbidity and equal or greater precision is particularly relevant. The use of the sentinel lymph node biopsy is intended to reach that purpose. The present study reviews recent literature on the role of sentinel lymph node biopsy in cervical cancer, analyzing its indications and contraindications, injection and detection techniques, tracers used, surgical and pathological approaches and its applicability in up-to-date clinical practice. 相似文献