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81.
The invasive phenotype of glioblastoma multiforme (GBM) is a hallmark of malignant process, yet the molecular mechanisms that dictate this locally invasive behavior remain poorly understood. Over-expression of PIAS3 effectively changes cell shape and inhibits GBM cell migration. We focused on the molecular target(s) of PIAS3 stimulated sumoylation, which play an important role in the inhibition of GBM cell motility. Here we report, through the immunoprecipitation with SUMO1 antibody, followed by proteomic analysis, the identification of vimentin (vimentin354), a nuclear component in GBM cells, as the main target of sumoylation promoted by PIAS3.  相似文献   
82.

Background  

Nasopharyngeal carcinoma (NPC) is a type of neoplasm that is highly prevalent in East Asia and Africa with Epstein-Barr virus (EBV), genetic, and dietary factors implicated as possible aetiologic factors. Previous studies suggested the association of certain cytokines with the invasion and metastatic properties of NPC. The present study examined the roles of EBV latent membrane protein-1 (LMP1), interleukin-6 (IL-6), interleukin-10 (IL-10), transforming growth factor-beta 1 (TGF-β1) and laminin in the regulation of matrix-metalloproteinases (MMPs) and vascular endothelial growth factor (VEGF) in NPC. The effects of these factors on bmi-1, an oncogene, and ngx6, a tumour suppressor gene, were also investigated.  相似文献   
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PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
84.
临床医护   总被引:1,自引:0,他引:1  
细菌的耐药笥民为一个全球性问题,并从医院扩展到了家庭及社区。同时,抗生素的滥用对微生物的生态环境造成了极大的破坏。我们可以通过改变抗生素的使用频度和改变耐药性基因来逆转药性问题,同时需要有一个全球性的监测系统来追踪耐药菌的、去向及新菌种的出现。  相似文献   
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Grinnell  BW; Walls  JD; Marks  C; Glasebrook  AL; Berg  DT; Yan  SB; Bang  NU 《Blood》1990,76(12):2546-2554
Human protein S (HPS), a regulator of hemostasis, is a vitamin K- dependent plasma protein with potential clinical utility. We have obtained high-level expression of the cDNA for HPS in two mammalian cell lines. Both cell lines secreted single chain recombinant HPS (rHPS) in serum-free medium as determined by Western blot analysis. The ability of the rHPS from both cell lines to act as a cofactor for human protein C (HPC) was determined; the rHPS secreted from the human 293 cell line had an activity six times that of the rHPS from the AV12-664 Syrian hamster cell line. Furthermore, the relative specific cofactor activity of rHPS from the 293 cell line was actually 2.5-fold higher than that of single-chain human plasma-derived HPS. Essentially all of the rHPS secreted from the 293 cell line exhibited a calcium-dependent elution profile on anion exchange chromatography, whereas only 25% to 35% of the hamster cell-derived rHPS exhibited this profile. However, the calcium-eluted rHPS from the AV12 cell line had a high specific cofactor activity, equivalent to that of the 293-derived rHPS. A NaCl- elutable rHPS fraction (calcium nondependent) was isolated from the recombinant AV12-664 cell line, further purified, and found to have reduced activity, only 40% that of the calcium-dependent rHPS. The only observable difference in the calcium-dependent and nondependent rHPS molecules was in the content of gamma-carboxyglutamic acid (Gla); the calcium-dependent material contained approximately 10 mol Gla/mol protein whereas the calcium-nondependent material contained only approximately 8 mol Gla/mol of protein. In addition, the calcium- nondependent rHPS had reduced ability to interact with phospholipid vesicles as evidenced by an eightfold increase in the apparent kd. Our data demonstrate the isolation of rHPS with high specific activity, and show that a reduction in as few as two Gla residues dramatically decreases its functional cofactor activity for HPC, due to a reduction in ability to interact with the phospholipid bilayer.  相似文献   
87.
Background Non‐ablative 1550‐nm erbium‐doped fractional photothermolysis systems (FPS) and 10 600‐nm carbon dioxide fractional laser systems (CO2 FS) have been effectively used to treat scars. Objective We compared the efficacy and safety of single‐session treatments of FPS and CO2 FS for acne scars through a randomized, split‐face, evaluator‐blinded study. Methods Eight patients with acne scars were enrolled in this study. Half of each subject’s face was treated with FPS and the other half was treated with CO2 FS. We used a quartile grading scale for evaluations. Results At 3 months after the treatment, the mean grade of improvement based on clinical assessment was 2.0 ± 0.5 for FPS and 2.5 ± 0.8 for CO2 FS. On each side treated by FPS and CO2 FS, the mean duration of post‐therapy crusting and scaling was 2.3 and 7.4 days respectively and that of post‐therapy erythema was 7.5 and 11.5 days respectively. The mean VAS pain score was 3.9 ± 2.0 with the FPS and 7.0 ± 2.0 with the CO2 FS. Conclusion We demonstrated the efficacy and safety of single‐session acne scar treatment using FPS and CO2 FS in East Asian patients. We believe that our study could be used as an essential reference when choosing laser modalities for scar treatment.  相似文献   
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90.
Medical imaging forms a vital component of radiotherapy treatment planning and its evaluation. The integration of the useful data obtained from multiple imaging modalities for radiotherapy planning is achieved by image registration softwares. In radiotherapy planning systems, normally the computed tomography (CT) slices are kept as a standard upon which other modality images (magnetic resonance imaging [MRI], single photon emission computed tomography [SPECT], positron emission tomography [PET], etc.) are aligned—automatically or interactively. Following validation of successful registration, they are resampled and reformatted, as per the requirements. This paper defines the minimum requirements of automatic image registration software for 3-dimensional (3D) radiotherapy planning and describes the implementation of a suitable graphical user interface developed in Visual Basic (version 5). The automatic image registration (AIR) routines freely available from Dr. Roger P. Woods, UCLA, (USA) were used in this software. This software could be easily implemented and was easy to use for image processing suitable for radiotherapy planning systems.  相似文献   
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