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71.
Effects of low-level laser therapy on malignant cells: in vitro study   总被引:4,自引:0,他引:4  
The aim of this study was to assess the effect of 635- and 670-nm laser irradiation on H.Ep.2 cells in vitro using MTT. In addition to our previous report on the effects of LLLT on the proliferation of laryngeal carcinoma cells in which it was found that irradiaton H.Ep.2 cells with 670-nm laser results in increased cell proliferation, it was decided to evaluate the effect of increased doses of laser light on these cells. The cells, obtained from SCC of the larynx, were routinely processed from defrost to the experimental condition. The cultures were kept either at 5% or 10% of FBS. Twenty-four hours after transplantation, the cells were irradiated with laser light (5-mW diode lasers; 635 and 670-nm; beam cross section approximately 1 mm) at local light doses between 0.04 and 4.8.10(4) Jm(-2). For 670 nm, significant differences in the proliferation were observed between the two concentrations of FBS (p = 0.002) and between irradiated cultures and controls (p = 0.000). Although the results were not significant, 635-nm irradiated cells also proliferated more than nonirradiated ones. This occurred under both conditions of nutrition. It is concluded, that irradiation with 670-nm laser light applied at doses between 0.04 and 4.810(4) Jm(-2) could significantly increase proliferation of laryngeal cancer cells.  相似文献   
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Moderate and severe reactions in blood donors   总被引:2,自引:0,他引:2  
During the period April 1985 to March 1986, 217 blood donors were found to have moderate (syncopal) to severe (convulsive) reactions. This population was compared to 5630 randomly selected donors who did not have reactions. An examination of demographic, physical, and societal/emotional factors was conducted to determine if any were predictive of reactions in donors. The results of the research supported the hypothesis that first-time donors have a higher frequency of reactions (1.7%) than do repeat donors (0.19%). A review of the above predictive factors documented that, with regard to demographic factors, 1) the number of prior donations was inversely proportional to the risk of reaction; 2) the gender of the donor was not predictive; and 3) youth was a predictor of reactions. An analysis of the physical factors revealed that donors who reacted were of lower weight (mean, 153.7 lb) than those who did not (mean, 166.4 lb) and that systolic blood pressure was slightly lower in the group with reactions. Although the difference was significant (3 torr), it was not thought to be significant clinically. In a comparison of a group with systolic blood pressure ranging from 80 to 100 torr and a group with systolic blood pressure ranging from 120 to 140 torr, the first group had a 70-percent higher risk of reaction. Finally, with regard to the last category of societal or emotional factors, the research demonstrates 1) that the ingestion of caffeinated beverages was associated with a reduced risk of reactions; 2) that the food intake of donors who reacred was significantly different from that of those who had no reaction, but this difference was not thought to be clinically significant; and 3) that the duration between registration and the onset of phlebotomy was directly predictive of reaction status. The research indicates that first-time donor status and several specific demographic, physical, and societal or emotional factors are predictors of donor reactions.  相似文献   
75.
A total of 323 children aged 4-11 years who were receiving, or had symptoms indicating a clinical requirement for, inhaled corticosteroid at a daily dose of 400 μg budesonide (BUD) or beclomethasone dipropionate (BDP), or 200 μg fluticasone propionate (FP), were randomised into this multicentre, open-label, parallel group study. Patients received either FP 100 μg b.d. administered via the Accuhaler/Diskus inhaler (n=159) or BUD 200 μg b.d. administered via a Turbohaler inhaler (n=164) for four weeks and recorded daily their morning and evening peak expiratory flow (PEF), asthma symptoms and use of relief medication. Device handling was assessed by a questionnaire, with responses recorded on three- or five-point ordinal scales. The primary efficacy parameter was mean percent predicted morning PEF. The device handling results showed the Accuhaler/Diskus inhaler was rated more favourably than the Turbohaler inhaler in terms of ease of correct inhaler use, ease of telling how many doses were left, ease of knowing whether a dose had been inhaled and overall liking of the device. More patients in the Accuhaler/Diskus group (85%) than in the Turbohaler group (58%) said they would be happy to receive the same device again, while 8% and 25% respectively said they would not be happy to be given it again. In addition, the change from baseline to week 4 of treatment in mean percent predicted morning PEF was greater in the FP Accuhaler/Diskus group, indicating that FP 200 μg daily via Accuhaler/Diskus inhaler is at least as clinically effective as BUD 400 μg daily via the Turbohaler inhaler.  相似文献   
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Arboviruses of the families Togaviridae and Flaviviridae are widely distributed and are important causative agents of viral encephalitis, a severe and often fatal disease. The only internationally available vaccine against these diseases is expensive and laborious to manufacture and difficult to administer. Therefore, new vaccines are required against these pathogens. This study investigates the use of a DNA-prime, orally delivered protein boost vaccination strategy against viral encephalitis. This vaccination strategy was immunogenic and provided partial protection against viral encephalitis in a murine model, demonstrating the possible applicability of this vaccination strategy for the management of endemic encephalitis.  相似文献   
78.

Background

The burden of lymphomas on the health care system in Nigeria is enormous. Correct diagnosis and identification of aetiological factor are important steps in reducing this burden.

Methods

Eight cases diagnosed as HL within a period of six years at the Obafemi Awolowo University teaching Hospital, Ile-Ife, Nigeria by haematoxylin and eosin (Hand E) only were immunophenotyped using the indirect immunoperoxidase method. Epstein-Barr virus latent membrane protein-1 (LMP-1), CD15 and CD30 immunohistochemistry was also performed. The clinical characteristics of each patient were documented.

Objectives

To document the frequency of involvement of Epstein-Barr virus in cases of HL seen in a university hospital in Nigeria.

Results

Out of the eight cases diagnosed by H&E as HL immunophenotyping showed only five were HL. The rest were non-Hodgkin''s lymphoma (2 diffuse large B-cell and 1 null cell ALCL). All were cases of classical HL with 60% being of the mixed cellularity (MC) subtype. There were 2 males and 3 females with ages ranging from 7 years to 40 years. All presented with cervical lymphadenopathy and three had splenomegaly in addition. 60% of the tumour was EBV positive, all of the MC subtype. Three patients had chemotherapy. Eventually all were lost to follow-up. There was no case of the nodular lymphocyte predominance variant.

Conclusion

Mixed cellularity is the most common subtype and is the only subtype associated with EBV positivity in this study. Epstein-Barr virus probably plays an important role in the aetiology of HL in Nigerians.Running title: Epstein-Barr virus, Hodgkin''s lymphoma in Nigerians  相似文献   
79.
We report a patient with a clinical and molecular diagnosis of LEOPARD syndrome (LS) associated with multiple granular cell tumors (MGCT). Bidirectional sequencing of exons 7, 12, and 13 of the PTPN11 gene revealed the T468M missense mutation in exon 12. This mutation has been previously reported in patients with LS. To our knowledge, this is the first report of MGCT associated with molecularly characterized LS and provides the first molecular evidence linking granular cell tumors (GCT) to the Ras/mitogen-activated protein (MAP) kinase pathway. We propose that MGCT can be associated with LS. Analysis of GCT from this case tested negatively for loss of heterozygosity (LOH) at the PTPN11 and NF1 loci and did not show deletions of the PTEN gene. The absence of LOH of PTPN11 supports published functional data that T468M is a dominant-negative mutation.  相似文献   
80.
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