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1.
Vitelliform dystrophy and pattern dystrophy of the retinal pigment epithelium: concomitant presence in a family.
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We describe three siblings presenting unusual pigmented dystrophic lesions of the fovea. The first sibling showed macroreticular dystrophy associated with butterfly shaped dystrophy in one eye and associated with vitelliform cyst in the other eye. The second showed the atrophic outcome of a vitelliform cyst with development of subretinal neovascular membrane in one eye and a radial pigmented macular dystrophy in the other eye. The third sibling had bilateral macular vitelliform lesions. This vitelliform patterned dystrophy of the retinal pigment epithelium may represent a new form that should be classified near Best's disease and the pattern dystrophies. 相似文献
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Montse García Elvira Méndez Cristina Martínez Mercè Peris Esteve Fernández 《European journal of cancer prevention》2006,15(5):446-452
The objective of the study was to describe the implementation of measures for preventing tobacco consumption developed in the Catalan Network of Smoke-free Hospitals. Information from 25 hospitals that are actively involved in the Catalan Network of Smoke-free Hospitals (April 2004) was used. The degree of implementation of the Smoke-free Hospitals Project was analysed by means of the Self-Audit Questionnaire of the European Network for Smoke-free Hospitals; each hospital was analysed globally and according to the duration of its Network membership (<1 year: implementation stage; > or =1 year: consolidation stage). In terms of global indicators, there were high levels of commitment (64.8%), communication (74.7%), tobacco control (77.4%) and implementation of smoke-free environments (81.0%). A lower degree of implementation (<50%) was found in education and training, health promotion and healthy workplaces. According to the duration of Network membership, significant differences were observed for communication, environment, healthy workplaces and follow-up. Deficits were observed in areas such as specialist training and cessation support, and further input is required here. By identifying areas needing attention, providing a guide for policy development and by administering it periodically, one can ensure that progress is kept on track. 相似文献
4.
Inducible nitric oxide synthase expression in human colorectal cancer: correlation with tumor angiogenesis 总被引:15,自引:0,他引:15
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Cianchi F Cortesini C Fantappiè O Messerini L Schiavone N Vannacci A Nistri S Sardi I Baroni G Marzocca C Perna F Mazzanti R Bechi P Masini E 《The American journal of pathology》2003,162(3):793-801
To investigate the potential involvement of the nitric oxide (NO) pathway in colorectal carcinogenesis, we correlated the expression and the activity of inducible nitric oxide synthase (iNOS) with the degree of tumor angiogenesis in human colorectal cancer. Tumor samples and adjacent normal mucosa were obtained from 46 surgical specimens. Immunohistochemical expression of iNOS, vascular endothelial growth factor (VEGF), and CD31 was analyzed on paraffin-embedded tissue sections. iNOS activity and cyclic GMP levels were assessed by specific biochemical assays. iNOS protein expression was determined by Western blot analysis. iNOS and VEGF mRNA levels were evaluated using Northern blot analysis. Both iNOS and VEGF expressions correlated significantly with intratumor microvessel density (r(s) = 0.31, P = 0.02 and r(s) = 0.67, P < 0.0001, respectively). A significant correlation was also found between iNOS and VEGF expression (P = 0.001). iNOS activity and cyclic GMP production were significantly higher in the cancer specimens than in the normal mucosa (P < 0.0001 and P < 0.0001, respectively), as well as in metastatic tumors than in nonmetastatic ones (P = 0.002 and P = 0.04, respectively). Western and Northern blot analyses confirmed the up-regulation of the iNOS protein and gene in the tumor specimens as compared with normal mucosa. NO seems to play a role in colorectal cancer growth by promoting tumor angiogenesis. 相似文献
5.
Licastro F Grimaldi LM Bonafè M Martina C Olivieri F Cavallone L Giovanietti S Masliah E Franceschi C 《Neurobiology of aging》2003,24(7):921-926
Two different polymorphic regions of the interleukin-6 (IL-6) gene were investigated in patients with Alzheimer's disease (AD) and non-demented controls. The -174 C allele in the promoter region of IL-6 gene was over-represented in AD patients compared to controls and significantly increased the risk of AD. Moreover, the -174 CC genotype was associated with a high risk of the disease in women. The D allele of a variable number of tandem repeat (VNTR) was in strong linkage disequilibrium with the -174 C allele and slightly increased AD risk. On the other hand, the frequency of the VNTR C allele was decreased in patients with AD and was negatively associated with the risk of developing AD. Both the -174 CC and VNTR DD genotypes were also associated with increased IL-6 levels in the blood and brain from AD. These findings suggest that IL-6 may play a multifaceted role in AD by affecting the turnover of the cytokine. 相似文献
6.
Age-dependent changes in the susceptibility to apoptosis of peripheral blood CD4+ and CD8+ T lymphocytes with virgin or memory phenotype 总被引:5,自引:0,他引:5
Salvioli S Capri M Scarcella E Mangherini S Faranca I Volterra V De Ronchi D Marini M Bonafè M Franceschi C Monti D 《Mechanisms of ageing and development》2003,124(4):409-418
Susceptibility to apoptosis changes with age and most of the available data on lymphocytes refer to mitogen stimulated cells. We studied this susceptibility in quiescent, purified CD4+ or CD8+ T cells from a group of Italian old people compared with a group of young people. We found that an apoptotic agent such as 2-deoxy-D-ribose (dRib), which acts via glutathione depletion and oxidative stress, was more effective in CD4+ T cells from young donors, while no difference was found in CD8+ T cells. On the contrary, another agent such as TNF-alpha, which acts via receptor engagement, was more effective in CD8+ T cells from old subjects, and no difference was found in CD4+ T cells. When marker of activation-memory were investigated, no difference between young and old subjects was found when dRib was used. Differently, when TNF-alpha was used, memory and activated CD4+ T cells from old donors were less sensitive than younger counterparts, while memory CD8+ T cells from old donors were more sensitive than younger counterparts. This suggests that age-related changes in susceptibility to apoptosis of resting T cells largely depend on the type of the apoptotic stimulus which is used as well as on the memory phenotype of the cells. These results may also account, at least in part, for the deep remodelling of T cell repertoire that occurs during ageing. 相似文献
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Paolo Lionetti Jo Spencer Emma J. Breese Simon H. Murch Jacqueline Taylor Thomas T. Macdonald 《European journal of immunology》1993,23(3):664-668
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506. 相似文献
9.
Reduced Left Ventricular Compliance and Mechanical Efficiency after Prolonged Inhibition of NO Synthesis in Conscious Dogs 总被引:1,自引:0,他引:1
Heiner Post Chiara d'Agostino Vincenzo Lionetti Michele Castellari Elaine Y. Kang Martin Altarejos Xiaobin Xu Thomas H. Hintze Fabio A. Recchia 《The Journal of physiology》2003,552(1):233-239
Acute inhibition of NO synthesis decreases left ventricular (LV) work and external efficiency, but it is unknown whether compensatory mechanisms can limit the alterations in LV mechanoenergetics after prolonged NO deficiency. Eight chronically instrumented male mongrel dogs received 35 mg kg−1 day−1 of N ω -nitro-L-arginine methyl ester orally for 10 days to inhibit NO synthesis. At spontaneous beating frequency, heart rate, coronary blood flow, peak LV pressure, end-diastolic LV pressure and the maximum derivative of LV pressure (d P /d t max ) were not significantly different vs. baseline, whereas LV end-diastolic diameter (32.5 ± 1.0 vs. 37.6 ± 1.4 mm) and LV stroke work (515 ± 38 vs. 650 ± 44 mmHg mm), were reduced (all P < 0.05). The slope of the LV end-systolic pressure-diameter relationship was increased at 10 days vs. baseline (13.9 ± 1.0 vs. 9.6 ± 0.9 mmHg mm−1 , P < 0.05), while the end-diastolic LV diameter was smaller at matched LV end-diastolic pressures. At fixed heart rate (130 beats min−1 ), cardiac oxygen consumption was increased (12.2 ± 1.5 vs. 9.9 ± 1.0 ml min−1 ), and the ratio between stroke work and oxygen consumption was decreased by 33 ±7 % (all P < 0.05) after NO inhibition. We conclude that sustained inhibition of NO synthesis in dogs causes a decrease in LV work despite an increased contractility, which is most probably due to reduced diastolic compliance and a decrease in external efficiency. Thus, prolonged NO deficiency is not compensated for on the level of LV mechanoenergetics in vivo . 相似文献
10.
Massè A Bosetti M Buratti C Visentin O Bergadano D Cannas M 《Journal of biomedical materials research. Part B, Applied biomaterials》2003,67(2):750-757
A prospective multicentric study was carried out in patients having metal-on-metal METASUL components (Sulzer Medica, Winterthur, Switzerland) in order to check the following null hypotheses: H1: The concentration of Co, Cr, Ni, and Mb in blood and urine is not modified by the implant of a hip prosthesis with METASUL components at 6 months. H2: The incidence of markers of chromosomal damage [sister chromatid exchanges (SCEs) and micronuclei (Mni)] in lymphocytes is not modified by the implant of METASUL components at 6 months. H3: The concentrations of Co, Cr, Ni, and Mb in blood and urine did not correlate with the incidence of the markers of chromosomal damage. The measurements showed a 2-fold increase of Co in blood, a 10-fold increase of Co in urine, a 1.5-fold increase of Cr in the blood, and a 3-fold increase of Cr in the urine at a follow-up of 6 months from the operation; there was also a significant increase in the Ni blood concentration at the 7 day checkup. The study cohort did not show any modification in the frequency of markers of chromosomal damage in the peripheral lymphocytes at any of the observation times. The amount of the SCEs and Mni recorded at all the observation times did not correlate with each other or with any of the ion levels measured in the blood and in the urine. 相似文献