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21.
Detection of Epstein-Barr virus in oral squamous cell carcinoma suggests its involvement in the carcinogenesis of oral cavity. But, there are few studies on the incidence of EBV genome in squamous cell carcinomas at specific locations in the oral cavity like tongue and with different tumor progression. In this study the presence of EBV genome in tongue Squamous Cell Carcinoma (TSCC) in Iranian patients were investigated. Accordingly, a total of 94 cases with TSCC were firstly analyzed for the presence of viral genome through Nested PCR. Patients were divided into different groups based on their gender and the size, nodal involvement, grade and stage of their tumor. Results showed the presence of EBV genome in 72.3% of TSCCs with no significant difference between two genders, although slightly higher in females. Interestingly, PCR products of EBV genome showed a statistically significant higher distribution in TSCCs at IVa stage (p = 0.04), while a considerable low involvement of EBV genome was seen in T1-sized tumors. The result of this study further emphasizes the role of EBV in oral SCCs – mainly at tongue. This is the first investigation to clarify the association between EBV genome and different tumor size and stage in TSCCs; however, more studies in different regions and larger populations should be performed to be able to draw a firmed conclusion.  相似文献   
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Linear poly(ethylene glycol) (PEG)‐block‐poly(N‐isopropylacrylamide) (PNIPAM) and star‐like three‐arm PEG‐star‐(PNIPAM)2 copolymers having one PEG and two PNIPAM blocks are synthesized by atom transfer radical polymerization (ATRP). Single crystals of these block copolymers are grown from amyl acetate and toluene dilute solutions. To recognize PNIPAM and PEG thicknesses, small angle X‐ray scattering (SAXS) is applied. V‐type brushes behave differently from linear brushes because doubly grafted PNIPAM blocks from a common point onto PEG substrate exert a higher osmotic pressure, leading to a thinner crystal. In addition to three ordinary regimes, a fourth or extremely stretched regime is detected for V‐type PNIPAM brushes. Although in PEG5000star‐(PNIPAM)2 single crystals with overall PNIPAM molecular weight of 37 000 g/mol, each PNIPAM arm is shorter than PNIPAM grafts in linear PEG5000block‐PNIPAM26000 single crystals, their switching point from second to third regime is significantly lower (22 vs 33 °C). The V‐type configuration of PNIPAM brushes cause them to be entered into the extremely stretched or fourth regime, which has not been previously detected for coily brushes. The boundary between third and fourth regimes for PEG5000star‐(PNIPAM)2 single crystals is verified at 31.5 and 23.5 °C in amyl acetate and toluene, respectively.  相似文献   
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Brain tissue cells have been shown to use two predominant pathways for energy production. The first of these is the pentose phosphate shunt, and the second is glycolysis, followed by the TCA cycle. Inhibition of these pathways can result in a reduction of ATP, and changes in the concentration of various metabolites. In the present study, the acute and chronic effect of 6-aminonicotinamide (6-AN) (0.01, 0.02, and 0.03 mg/ml) was examined on astrocytes and C6-glioma cells. Following this treatment, glucose, lactate, glutamate, ATP, and PCr were assayed according to the procedures of Lowry and Passonneau. Our data indicated that following 15 minutes treatment of astrocytes and C6-glioma with 6AN there was no significant difference in the concentration of metabolites measured. However, following 24 hours treatment there was a significant increase in glucose concentration and significant reduction in the concentration of ATP, PCr, lactate and glutamate in both cell types. Morphological changes appeared later following 48 hours treatment with 6-AN in both cell types. Glucose accumulation can be explained by the fact that it is the precursor to both glycolysis and the pentose phosphate shunt. If these processes are inhibited, glucose will obviously accumulate and products like ATP, PCr, lactate and glutamate will decrease. Additionally, there was significant differences in concentration of glucose and lactate between astrocytes and C6-glioma cells. The significance of these differences has been discussed.  相似文献   
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Background

Haemodialysis patients may suffer from pain and impairment of quality of life. Some complementary interventions, such as relaxation therapy, might affect the pain and quality of life. The present study aimed to identify the effectiveness of Benson's relaxation technique in relieving pain and improving the quality of life in haemodialysis patients.

Study design

The study was a randomized controlled trial.

Setting and participants

The data were collected in two haemodialysis units affiliated to Shiraz University of Medical Sciences. A total of 86 haemodialysis patients were randomly assigned to either the intervention (receiving Benson's relaxation technique) or the control group (routine care) from 2011 to 2012.

Intervention

The patients in the intervention groups listened to the audiotape of relaxation technique twice a day each time for 20 min for eight weeks.

Measurements and outcomes

The pain numeric rating scale and Ferrans and Powers Quality of Life Index-dialysis version questionnaire were completed at baseline and 8 weeks after the intervention. The data were analyzed using independent t-test and ANCOVA.

Results

The results of ANCOVA showed a significant difference between the intervention and the control group concerning the mean score of the intensity of pain (F = 6.03, p = 0.01). Moreover, a significant difference was found between the intervention and the control group regarding the total quality of life (F = 10.20, p = 0.002) and health-functioning (F = 8.64, p = 0.004), socioeconomic (F = 12.45, p = 0.001), and family (F = 8.52, p = 0.005) subscales of quality of life.

Conclusion

These findings indicated that Benson's relaxation technique might relieve the intensity of pain and improve the quality of life in haemodialysis patients. Thus, Benson's relaxation technique could be used as part of the care practice for relieving the pain intensity and improvement of the quality of life in haemodialysis patients.  相似文献   
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Metastasis is the major cause of prostate cancer deaths and there is a need for clinically relevant in vivo models allowing elucidation of molecular and cellular mechanisms underlying metastatic behavior. Here we describe the development of a new in vivo model system for metastatic prostate cancer. Pieces of prostate cancer tissue from a patient were grafted in testosterone-supplemented male NOD-SCID mice at the subrenal capsule graft site permitting high tumor take rates. After five serial transplantations, the tumor tissues were grafted into mouse prostates. Resulting tumors and suspected metastatic lesions were subjected to histopathological and immunohistochemical analysis. Samples of metastatic tissue were regrafted in mouse anterior prostates and their growth and spread examined, leading to isolation from lymph nodes of a metastatic subline, PCa1-met. Orthotopic grafting of PCa1-met tissue in 47 hosts led in all cases to metastases to multiple organs (lymph nodes, lung, liver, kidney, spleen and, notably, bone). Histopathological analysis showed strong similarity between orthotopic grafts and their metastases. The latter were of human origin as indicated by immunostaining using antibodies against human mitochondria, androgen receptor, prostate-specific antigen and Ki-67. Spectral karyotyping showed few chromosomal alterations in the PCa1-met subline. This study indicates that transplantable subrenal capsule xenografts of human prostate cancer tissue in NOD-SCID mice can, as distinct from primary cancer tissue, be successfully grown in the orthotopic site. Orthotopic xenografts of the transplantable tumor lines and metastatic sublines can be used for studying various aspects of metastatic prostate cancer, including metastasis to bone.  相似文献   
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OBJECTIVE: To study the effect of folic acid on homocysteine (Hcy) levels in women with insulin resistance and polycystic ovary syndrome (PCOS) in a prospective clinical trial. METHOD: Of 210 women with PCOS, 70 were hyperhomocysteinemic; and of these, 32 were insulin resistant and 38 were not. The 70 women were treated with folic acid for 3 months. Baseline and serum levels of Hcy and insulin were measured in both groups. RESULTS: In both groups Hcy concentrations were significantly decreased following folic acid supplementation. The mean+/-SD levels before and after treatment were 14.03+/-1.5 micromol/L and 12.53+/-1.72 micromol/L in group 1 (P<0.001), and they were 12.07+/-0.87 micromol/L and 8.83+/-0.78 micromol/L in group 2 (P<0.001). CONCLUSION: The Hcy levels of hyperhomocysteinemic women with PCOS were reduced after 3 months of folic acid supplementation, and the rate of reduction was higher among women without insulin resistance. No change was found in fasting insulin levels.  相似文献   
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