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排序方式: 共有382条查询结果,搜索用时 93 毫秒
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Increasing evidence points to the beneficial effects of carotenoid antioxidants in the human body. Several studies, for example, support the protective role of lutein and zeaxanthin in the prevention of age-related eye diseases. If present in high concentrations in the macular region of the retina, lutein and zeaxanthin provide pigmentation in this most light sensitive retinal spot, and as a result of light filtering and/or antioxidant action, delay the onset of macular degeneration with increasing age. Other carotenoids, such as lycopene and beta-carotene, play an important role as well in the protection of skin from UV and short-wavelength visible radiation. Lutein and lycopene may also have protective function for cardiovascular health, and lycopene may play a role in the prevention of prostate cancer. Motivated by the growing importance of carotenoids in health and disease, and recognizing the lack of any accepted noninvasive technology for the detection of carotenoids in living human tissue, we explore resonance Raman spectroscopy as a novel approach for noninvasive, laser optical carotenoid detection. We review the main results achieved recently with the Raman detection approach. Initially we applied the method to the detection of macular carotenoid pigments, and more recently to the detection of carotenoids in human skin and mucosal tissues. Using skin carotenoid Raman instruments, we measure the carotenoid response from the stratum corneum layer of the palm of the hand for a population of 1375 subjects and develop a portable skin Raman scanner for field studies. These experiments reveal that carotenoids are a good indicator of antioxidant status. They show that people with high oxidative stress, like smokers, and subjects with high sunlight exposure, in general, have reduced skin carotenoid levels, independent of their dietary carotenoid consumption. We find the Raman technique to be precise, specific, sensitive, and well suitable for clinical as well as field studies. The noninvasive laser technique may become a useful method for the correlation between tissue carotenoid levels and risk for malignancies or other degenerative diseases associated with oxidative stress. 相似文献
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Recent advances in diagnosis and management of pulmonary hypertension in chronic lung disease 总被引:2,自引:0,他引:2
NV Subhedar 《Acta paediatrica (Oslo, Norway : 1992)》2004,93(S444):29-32
Pulmonary hypertension with elevated pulmonary vascular resistance is a common cardiovascular complication associated with increased morbidity and mortality in preterm infants with chronic lung disease. Injury to the developing pulmonary circulation results in structural and functional abnormalities of the pulmonary vasculature. Animal studies have demonstrated that disruption of angiogenesis may contribute to the failure of normal alveolarisation in chronic lung disease. Levels of vascular endothelial growth factor in bronchoalveolar lavage fluid are lower in infants with chronic lung disease compared to preterm controls. Supplemental oxygen is commonly used to prevent and treat pulmonary hypertension, although optimal arterial oxygen saturation levels remain uncertain. Other vasodilators such as inhaled nitric oxide appear promising, but as yet have not been evaluated in the form of randomised controlled trials. Further studies are required to investigate the long-term effectiveness of pulmonary vasodilator therapy. 相似文献
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Background:
There is paucity of information on the relationship of quality of life (QOL) in obsessive compulsive disorder (OCD) and dysthymic disorder (DD) with disability grade in India.Aim:
To assess the relation of QOL with disability level in OCD and DD.Materials and Methods:
This hospital based study was conducted in a medical institution in Davanagere, Karnataka, India. Data was collected by using Diagnostic and Statistical Manual IV Text Revision (DSM IV TR) criteria, WHO QOL BREF and IDEAS. Relationship between disability grade and QOL was assessed by independent sample t test.Results:
Mild disabled OCD patients had a significantly better QOL in the Q1 domain i.e. perception on quality of life as compared to moderately disabled patients (P < 0.05), while in other domains of QOL, there was no statistically significant difference (P > 0.05). But, QOL score in physical domain showed significant difference across disability grades (56.00, SD = 6.89; 48.50, SD = 12.28) in DD, but not in other domains.Conclusion:
Perception of QOL is better in those with mild disability in OCD, but in DD, physical domain of QOL score is more in mild disability compared to moderate disability. 相似文献7.
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Luo D Liu QF Gove C Naomov N Su JJ Williams R 《World journal of gastroenterology : WJG》1998,4(2):97-99
AIM:To study the relationship between N-ras gene mutation and p53 gene expression in the carcinogenesis and the development of human hepatocellular carcinomas (HCC).METHODS:The N-ras gene mutation and the p53 gene expression were analyzed in 29 cases of HCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemistry.RESULTS:Thirteen cases of HCCs were p53 positive (44.8%), which showed a rather high Cpercen-tage of p53 gene mutation in Guangxi. The aberrations at N-ras codon 2-37 were found in 79.31% of HCCs and 80.77% of adjacent non-tumorous liver tissues. More than 2 point mutations of N-ras gene were observed in 22 cases (75.86%). Twelve cases (41.37%) of HCCs showed both N-ras gene mutation and p53 gene expression.CONCLUSION:N-ras gene and p53 gene may be involved in the carcinogenesis and the development of HCC.That 38% of HCCs with N-ras gene mutation did not express p53 protein indicates that some other genes or factors may participate in the carcinogenesis and the development of HCC. 相似文献
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Role of antiphospholipid antibodies in occlusion of retinal vessels in various vascular eye diseases
Ermakova NA Alekberova ZS Nasonov EL Kosheleva NM Reshetniak TM Aleksandrova EN 《Vestnik oftalmologii》2002,118(2):29-32
A strong association between the presence of antiphospholipid antibodies (aPLab) and arterial and venous thrombosis was observed during the past decade. aPLab represent a heterogeneous group of immunoglobulins that include the lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and antibodies responsible for false-positive test for syphilis. aPLab react with negatively charged, rarely with neutral phospholipids and/or phospholipid-binding proteins. aPLab are associated with vascular occlusion in autoimmune diseases, e.g. systemic lupus erythematosus (SLE). The role of aCL in ocular vascular occlusive disease involving retinal vessels is unclear. The aim of this study was to determine the relationship between aPLab and occlusive retinal disease. A relationship between aCL (IgG), LA, and thrombotic retinal events has been detected in SLE patients, but no association between aPLab and other occlusive retinal diseases (central retinal vein thrombosis, isolated retinal vasculitis, optic nerve vasculitis). In our study the incidence of aCL IgG was higher in patients with Behcet disease with non-occlusive thrombosis than in patients with retinal occlusive events or in patients without occlusions or thrombosis. It seems that different mechanisms are responsible for these conditions. 相似文献