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71.
Lei Zeng Yun-Ming Tian Ying Huang Xue-Ming Sun Feng-Hua Wang Xiao-Wu Deng Fei Han Tai-Xiang Lu 《PloS one》2014,9(9)
Purpose
The purpose of this retrospective study was to identify the independent prognostic factors and optimize the treatment for nasopharyngeal carcinoma (NPC) patients with distant metastasis at initial diagnosis.Methods
A total of 234 patients referred between January 2001 and December 2010 were retrospectively analyzed. Among the 234 patients, 94 patients received chemotherapy alone (CT), and 140 patients received chemoradiotherapy (CRT). Clinical features, laboratory parameters and treatment modality were examined with univariate and multivariate analyses.Results
The median overall survival (OS) time was 22 months (range, 2-125 months), and the 1-year, 2-year, 3-year overall survival rates were 82.2%, 51.3% and 34.1%. The overall response and disease control rates of metastatic lesions after chemotherapy were 56.0% and 89.8%. The factors associated with poor response were karnofsky performance score (KPS) <80, liver metastasis, lactate dehydrogenase (LDH)>245 IU/L, and number of chemotherapy cycles <4. The 3-year OS of patients receiving CRT was higher than those receiving CT alone (48.2% vs. 12.4%, p<0.001). Subgroup analysis showed that significantly improved survival was also achieved by radiotherapy of the primary tumor in patients who achieved complete remission (CR)/partial remission (PR) or stable disease (SD) of metastatic lesions after chemotherapy. Significant independent prognostic factors of OS were KPS, liver metastasis, levels of LDH, and multiple metastases. Treatment modality, response to chemotherapy and chemotherapy cycles were also associated with OS.Conclusion
A combination of radiotherapy and chemotherapy seems to have survival benefits for selected patients with distant metastases at initial diagnosis. Clinical and laboratory characteristics can help to guide treatment selection. Prospective randomized studies are needed to confirm the result. 相似文献72.
Rui André Saraiva Raposo Mohamed Abdel-Mohsen Xutao Deng Frederick M. Hecht Christopher D. Pilcher Satish K. Pillai Douglas F. Nixon 《Journal of virology》2014,88(19):11624-11629
In this study, we investigated the expression levels of host restriction factors in six untreated HIV-1-positive patients over the course of infection. We found that the host restriction factor gene expression profile consistently increased over time and was significantly associated with CD4+ T cell activation and viral load. Our data are among the first to demonstrate the dynamic nature of host restriction factors in vivo over time. 相似文献
73.
74.
[目的]本文从胜利油田沾3区块的高温油藏的原油采出液中分离得到一株嗜热菌,通过其与膨润土的相互作用,尝试探讨油藏微生物作为油藏储层中水敏性矿物(如蒙皂石)改性剂的可能性。[意义]研究结果将在降低水敏矿物的膨胀性能,为解决水驱采油中遇到的水敏效应的瓶颈问题提供微生物的新途径。[结果]所得菌株为革兰氏阳性菌,呈杆状,具芽孢,兼性厌氧,鉴定为Geobacillus icigianus SL-1。菌株SL-1在厌氧条件下能够还原蒙皂石的结构铁。扫描电镜(SEM)结果显示,无菌对照体系中,蒙皂石呈不规则薄片状。而经微生物作用后,除薄片状蒙皂石外,另有板状次生矿物的生成。进一步能谱(EDS)分析表明,与薄片状蒙皂石相比,板状矿物含有较高的Al/Si比值,且含有明显的K+信号。XRD结果显示,经过微生物作用后,固相物质中蒙皂石的百分比下降至47.7%,伊利石百分比上升至29.1%,而无菌对照组中蒙皂石的百分含量则为70.4%,伊利石的百分比则为19.8%。XRD物相分析和EDS结果均证实经过微生物作用后,部分蒙皂石转化成了伊利石。膨胀性能的分析进一步揭示菌株SL-1作用后,矿物膨胀性较初始矿物显著降低,缩膨率达到25.9%。以上结果为油藏储层防膨提供了重要的实验依据。 相似文献
75.
Melanoma is an aggressive skin malignancy with a high mortality rate; however, successful treatment remains a clinical challenge. Ivermectin, a broad-spectrum antiparasitic drug, has recently been characterized as a potential anticancer agent due to its observed antitumor effects. However, the molecular mechanisms of ivermectin remain poorly understood. In the current study, we tested the involvement of autophagy in the ivermectin mechanism of action in human melanoma cells. We exposed SK-MEL-28 cells to different concentrations of ivermectin (2.5, 5, and 10 μM) for 24 hours. Here, ivermectin-induced apoptosis, as evidenced by the upregulation of cleaved poly (ADP-ribose) polymerase, BAX expression, and caspase-3 activity and downregulation of BCL-2 expression. In line with the apoptosis response, ivermectin triggered autophagy. Pharmacological or genetic inhibition of autophagy further sensitized SK-MEL-28 cells to ivermectin-induced apoptosis. Mechanistically, ivermectin-induced TFE3(Ser321) dephosphorylation, activated TFE3 nuclear translocation and increased TFE3 reporter activity, which contributed to lysosomal biogenesis and the expression of autophagy-related genes, and subsequently, initiated autophagy in SK-MEL-28 cells. Moreover, N-acetyl-cysteine, an reactive oxygen species (ROS) scavenger, abrogated the effects of ivermectin on TFE3-dependent autophagy. Taken together, we demonstrated that ivermectin increases TFE3-dependent autophagy through ROS signaling pathways in human melanoma cells and that inhibiting autophagy enhances ivermectin-induced apoptosis in human melanoma cells. 相似文献
76.
采用乙醇提取,用分光光度法测定的方法,以红柄白鹃梅为原料,通过正交试验研究了乙醇浓度,提取温度,提取时间和料液比4个因素对提取红柄白鹃梅叶片中总黄酮含量的影响。研究结果表明,各试验因素对红柄白鹃梅叶中黄酮类物质提取量的影响依料液比、提取温度、乙醇浓度、提取时间因素顺次降低,当提取温度为70℃、提取时间为2 h、料液比为1∶20时,提取效果最好,黄酮类物质提取量为22.412 mg/g。 相似文献
77.
Effects of Nickel Chloride on the Erythrocytes and Erythrocyte Immune Adherence Function in Broilers
Jian Li Bangyuan Wu Hengmin Cui Xi Peng Jing Fang Zhicai Zuo Junliang Deng Xun Wang Kun Tang Shuang Yin 《Biological trace element research》2014,161(2):173-179
This study was conducted to investigate the immune adherence function of erythrocytes and erythrocyte induced by dietary nickel chloride (NiCl2) in broilers fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl2 for 42 days. Blood samples were collected from five broilers in each group at 14, 28, and 42 days of age. Changes of erythrocyte parameters showed that total erythrocyte count (TEC), hemoglobin (Hb) contents, and packed cell volume (PCV) were significantly lower (p?0.05 or p?0.01) and erythrocyte osmotic fragility (EOF) was higher (p?0.05 or p?0.01) in the 600 and 900 mg/kg groups at 28 and 42 days of age than those in the control group, and the sodium-potassium adenosine triphosphatase (Na+/K+-ATPase) and calcium adenosine triphosphatase (Ca2+-ATPase) activities were significantly decreased (p?0.05 or p?0.01) in the NiCl2-treated groups. The results of erythrocyte immune adherence function indicated that erythrocyte C3b receptor rosette rate (E-C3bRR) was significantly decreased (p?0.05 or p?0.01) in the 600 and 900 mg/kg groups and in the 300 mg/kg group at 42 days of age, whereas the erythrocyte immune complex rosette rate (E-ICRR) was markedly increased (p?0.05 or p?0.01) in the 300, 600, and 900 mg/kg groups at 28 and 42 days of age. It was concluded that dietary NiCl2 in excess of 300 mg/kg caused anemia and impaired the erythrocytic integrity, erythrocytic ability to transport oxygen, and erythrocyte immune adherence function in broilers. Impairment of the erythrocytes and erythrocyte immune adherence function was one of main effect mechanisms of NiCl2 on the blood function. 相似文献
78.
Zhenyu Jia Michael B. Lilly James A. Koziol Xin Chen Xiao-Qin Xia Yipeng Wang Douglas Skarecky Manuel Sutton Anne Sawyers Herbert Ruckle Philip M. Carpenter Jessica Wang-Rodriguez Jun Jiang Mingsen Deng Cong Pan Jian-guo Zhu Christine E. McLaren Michael J. Gurley Chung Lee Michael McClelland Thomas Ahlering Michael W. Kattan Dan Mercola 《PloS one》2014,9(1)
It is difficult to construct a control group for trials of adjuvant therapy (Rx) of prostate cancer after radical prostatectomy (RP) due to ethical issues and patient acceptance. We utilized 8 curve-fitting models to estimate the time to 60%, 65%, … 95% chance of progression free survival (PFS) based on the data derived from Kattan post-RP nomogram. The 8 models were systematically applied to a training set of 153 post-RP cases without adjuvant Rx to develop 8 subsets of cases (reference case sets) whose observed PFS times were most accurately predicted by each model. To prepare a virtual control group for a single-arm adjuvant Rx trial, we first select the optimal model for the trial cases based on the minimum weighted Euclidean distance between the trial case set and the reference case set in terms of clinical features, and then compare the virtual PFS times calculated by the optimum model with the observed PFSs of the trial cases by the logrank test. The method was validated using an independent dataset of 155 post-RP patients without adjuvant Rx. We then applied the method to patients on a Phase II trial of adjuvant chemo-hormonal Rx post RP, which indicated that the adjuvant Rx is highly effective in prolonging PFS after RP in patients at high risk for prostate cancer recurrence. The method can accurately generate control groups for single-arm, post-RP adjuvant Rx trials for prostate cancer, facilitating development of new therapeutic strategies. 相似文献
79.
Haitao Shi Xin Wang Tiantian Ye Fangfang Chen Jiao Deng Pingfang Yang Yansheng Zhang Zhulong Chan 《Plant physiology》2014,165(3):1367-1379
80.