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71.

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   
72.
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   
73.
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   
74.

Objective

High blood pressure is one of the most important risk factors, directly responsible for increasing the cardiovascular morbidity and mortality. The primary objective was to evaluate the efficacy of metoprolol XL/chlorthalidone against metoprolol XL/hydrochlorothiazide with respect to mean fall in systolic and diastolic blood pressure. The secondary objective was to compare the response rates and to evaluate the tolerability of study medications in patients with mild-tomoderate essential hypertension.

Methods

Total 130 eligible patients (65: metoprolol XL 25 mg/chlorthalidone 6.25 mg; 65: metoprolol XL 25 mg/HCTZ 12.5 mg) were enrolled in this randomized, comparative, multicentric, 12-weeks study. Sixty-two patients from each group completed the study. After 4-weeks of treatment, non-responders from chlorthalidone 6.25 mg combination group were shifted to metoprolol XL 50 mg/chlorthalidone 12.5 mg and non-responders from HCTZ 12.5 mg combination group were escalated to metoprolol XL 50 mg/HCTZ 12.5 mg.

Results

The study treatment groups were comparable with respect to demography and baseline disease characteristics. Both the starting therapies were comparable with respect to mean fall in SBP (p = 0.788) and DBP (p = 0.939), and response rates (p = 1.0) after 4-weeks of therapy. Also both the step-up therapies showed similar mean fall in SBP (p = 0.277) and DBP (p = 0.507) at the end of 12-weeks. However, significantly more number of patients from chlorthalidone 12.5 mg/metoprolol XL 50 mg group responded to therapy as compared to that from HCTZ 12.5 mg/metoprolol XL 50 mg group (p = 0.045). All the reported adverse events were of mild-to-moderate intensity. There were no clinically significant trends in electrolytes (Na+, K+, Cl-)and fasting blood sugar, evident across the treatment groups.

Conclusion

Chlorthalidone in combination with metoprolol XL is as effective and well tolerated as widely used combination of metoprolol XL/HCTZ, thus providing an alternative therapeutic option.  相似文献   
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78.
There is currently substantial clinical interest in growth hormone (GH) as a protective agent against radiation-related normal tissue injury. To further assess the potential radiation injury-preventive effects of GH, these effects were studied in rats by using a radiation-induced skin injury model. Group 1 received neither GH nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (radiation group). Group 3 and 4 received the same irradiation plus either 0.01 U/kg/day GH (RT + 0.01 GH group) or 0.02 U/kg/day GH (RT + 0.02 GH group) subcutaneously. Clinically and histopathologically, acute skin reactions were assessed by two independent experts in radiation oncology and pathology, respectively. Irradiation increased dermatitis in rats when compared with the control group. The severity of radiodermatitis in the rats in the RT + 0.01 GH and RT + 0.02 GH groups was significantly lower than that in the RT group; radiodermatitis developed earlier in the RT group than in the other groups. GH was efficacious in preventing epidermal atrophy, dermal degeneration such as oedema and collagen fibre loss, and hair follicle atrophy, but not better than in the control group. These results are preliminary to studies that will be performed with higher doses of GH in radiation-treated cancer patients, with the aim of reducing radiation-induced toxicity.  相似文献   
79.
人白血病HL60细胞的分化状态对细胞凋亡的影响   总被引:2,自引:0,他引:2  
用细胞培养和流式细胞术等方法,研究人白血病HL60细胞诱导分化后,对三尖杉酯碱(Har)和喜树碱(Cam)诱导细胞凋亡的影响。结果表明,12-豆蔻酰及13-乙酸佛波酯以16nmol·L-1浓度处理HL60细胞24h,细胞向单核/巨噬细胞方向分化,阻断于G1期;分化细胞抗Har和Cam诱导的细胞凋亡,但其c-myc基因的表达无变化。1.4%二甲基亚砜处理HL60细胞48h,细胞向粒细胞方向分化,阻断于G1期;分化细胞抗Cam,而不抗Har诱导的细胞凋亡;分化细胞的c-myc基因表达明显下降。结果提示,人白血病HL60细胞的分化状态,明显影响三尖杉酯碱和喜树碱诱导的细胞凋亡,但可能与c-myc基因的表达变化无关。  相似文献   
80.
利用Dot blot 和流式细胞术,研究了分化诱导剂维甲酸,DMSO对HL-60细胞及其抗性亚型抗药性程度的影响,表明1μmol·ml-1 RA 作用H-60及其亚型24h, MDR 1 mRNA 明显增高,但流式检测多药抗性细胞系对Rho-123的外排有所下降。2%DMSO作用HL-60及其亚型 24h,流式细胞术检测显示各细胞系对Rho-123 的外排明显增强,提示RA 虽然提高MDR 1基因的表达,但可能通过磷酸化/脱磷酸化方式抑制Pgp-170功能的表达,而DMSO能诱导完整功能的Pgp表达。  相似文献   
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