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排序方式: 共有887条查询结果,搜索用时 15 毫秒
51.
There is increasing evidence that nuts have protective effects against coronary artery disease by improving lipid profile and inhibiting lipid oxidation. However, data about pistachio nuts are limited, and to our knowledge, there is no study investigating the effects of pistachio intake on lipid oxidation and serum antioxidant levels. This study, therefore, sought to determine the effects of pistachio intake on serum lipids and determine whether consumption of pistachio would alter serum antioxidant levels. Rats were randomly divided into three groups (n=12 for each): control group fed basic diet for 10 weeks and treated groups fed basic diet plus pistachio which constituted 20% and 40% of daily caloric intake, respectively. Consumption of pistachio as 20% of daily caloric intake increased high-density lipoprotein (HDL) levels and decreased total cholesterol (TC)/HDL ratio, compared with those not taking pistachio. However, TC, low-density lipoprotein (LDL) cholesterol and triglyceride levels were unaffected by pistachio consumption. Consumption of pistachio as 20% of daily caloric intake increased serum paraoxonase activity by 35% and arylesterase activity by 60%, which are known to inhibit LDL cholesterol oxidation, compared with the control group. However, increased antioxidant activity was blunted when pistachio intake was increased to 40% of daily caloric intake. In conclusion, the present results show that consumption of pistachio as 20% of daily caloric intake leads to significant improvement in HDL and TC/HDL ratio and inhibits LDL cholesterol oxidation. These results suggest that pistachio may be beneficial for both prevention and treatment of coronary artery disease.  相似文献   
52.
Inhibition of the cannabinoid receptor CB1 (CB1-R) exerts numerous positive cardiovascular effects such as modulation of blood pressure, insulin sensitivity and serum lipid concentrations. However, direct vascular effects of CB1-R inhibition remain unclear. CB1-R expression was validated in vascular smooth muscle cells (VSMCs) and aortic tissue of mice. Apolipoprotein E-deficient (ApoE−/−) mice were treated with cholesterol-rich diet and the selective CB1-R antagonist rimonabant or vehicle for 7 weeks. CB1-R inhibition had no effect on atherosclerotic plaque development, collagen content and macrophage infiltration but led to improved aortic endothelium-dependent vasodilation and decreased aortic reactive oxygen species (ROS) production and NADPH oxidase activity. Treatment of cultured VSMC with rimonabant resulted in reduced angiotensin II-mediated but not basal ROS production and NADPH oxidase activity. CB1-R inhibition with rimonabant and AM251 led to down-regulation of angiotensin II type 1 receptor (AT1-R) expression, whereas stimulation with the CB1-R agonist CP 55,940 resulted in AT1-R up-regulation, indicating that AT1-R expression is directly regulated by the CB1-R. CB2-R inhibition had no impact on AT1-R expression in VSMC. Consistently, CB1-R inhibition decreased aortic AT1-R expression in vivo. CB1-R inhibition leads to decreased vascular AT1-R expression, NADPH oxidase activity and ROS production in vitro and in vivo. This antioxidative effect is associated with improved endothelial function in ApoE−/− mice, indicating beneficial direct vascular effects of CB1-R inhibition.  相似文献   
53.
The aim of this study is to investigate if serum asymmetric dimethylarginine (ADMA) levels can predict restenosis and major adverse cardiac events (MACE) in patients who undergo percutaneous coronary interventions. The most important cause of restenosis following percutaneous coronary intervention is neointimal hyperplasia. Nitric oxide (NO) prevents the neointimal hyperplasia growing. Asymmetric dimethylarginine is a competitive inhibitor of NO synthesis. The effect of ADMA on the restenosis has not yet been investigated. A total of 105 (80 male and 25 female) patients were included in our study. All patients underwent elective percutaneous transluminal coronary angioplasty (PTCA) with bare metal stent implantation or direct stenting for one coronary artery between September 2004 and January 2006. All patients were clinically followed for a period of 6 months, and a control angiography was performed at the end of this period. The probrain natriuretic peptide (pro-BNP), high-sensitivity Creactive protein (hs-CRP), and ADMA levels of the patients were evaluated before the procedure and 6 months afterwards. Biochemical parameters and angiographic features were evaluated in order to determine if they could predict the development of restenosis and MACE by using univariate and multivariate Cox regression analysis. The 65 (61.9%) patients (50 males and 15 females) who had not developed restenosis were designated as Group 1. The 27 (25.7%) patients (21 males and 6 females) who had developed restenosis were designated as Group 2. In terms of predicting the development of restenosis, the presence of diabetes mellitus (hazard ratio [HR]: 2.78; confidence interval [CI]: 1.25–6.20; P = 0.01), type of lesion (HR: 1.89; CI: 1.01–3.55; P = 0.04), form of procedure (HR: 0.30; CI: 0.11–0.81; P = 0.01), and ADMA (HR: 4.08; CI: 1.73–9.62; P = 0.001) were found to be significant in univariate Cox regression analysis. In contrast, only the levels of ADMA were found to be a significant predictor of restenosis in the multivariate Cox regression analysis (HR: 3.02; CI: 1.16–7.84; P = 0.02). The restenosis prediction of ADMA levels continued after excluding the patients with diabetes mellitus in the univariate and multivariate Cox regression analysis (HR: 5.23; CI: 1.99–13.76; P = 0.001 and HR: 5.61; CI: 1.79–17.62; P = 0.003, respectively). Regarding the development of cardiac events, hs-CRP (HR: 1.03; CI: 1.00–1.06; P = 0.01) and ADMA (HR: 17.1; CI: 3.06–95.8; P = 0.001) were found to be significantly correlated with adverse cardiac events in univariate Cox regression analysis, whereas only ADMA levels were significant in the multivariate Cox regression analysis (HR: 2.83; CI: 1.27–6.31; P = 0.01). The levels of ADMA obtained before the procedure predict the development of restenosis and MACE in patients who underwent elective PTCA and bare metal stent procedures.  相似文献   
54.
55.
Sar V  Akyüz G  Doğan O 《Psychiatry research》2007,149(1-3):169-176
This study sought to determine the prevalence of dissociative disorders among women in the general population, as assessed in a representative sample of a city in central Turkey. The Dissociative Disorders Interview Schedule (DDIS), the Borderline Personality Disorder section of the Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II), and the PTSD-Module of the Structured Clinical Interview for DSM-III-R (SCID) were administered to 628 women in 500 homes. The mean age of participants was 34.8 (S.D.=11.5, range: 18-65); 18.3% of participants (n=115) had a lifetime diagnosis of a dissociative disorder. Dissociative disorder not otherwise specified (DDNOS) was the most prevalent diagnosis (8.3%); 1.1% of the population was diagnosed as having dissociative identity disorder (DID). Participants with a dissociative disorder had borderline personality disorder, somatization disorder, major depression, PTSD, and history of suicide attempt more frequently than did participants without a dissociative disorder. Childhood sexual abuse, physical neglect, and emotional abuse were significant predictors of a dissociative disorder diagnosis. Only 28.7% of the dissociative participants had received psychiatric treatment previously. Because dissociative disorders are trauma-related, significant part of the adult clinical consequences of childhood trauma remains obscure in the minds of mental health professionals and of the overall community. Revisions in diagnostic criteria of dissociative disorders in the DSM-IV are recommended.  相似文献   
56.
Sar V  Unal SN  Ozturk E 《Psychiatry research》2007,153(3):217-223
There is some evidence that emotional reactivity to daily life stress is related to a genetic or familial liability to develop schizophrenia. However, it is unclear whether the emotional distress is elevated in schizophrenia patients with positive compared to negative family history. The aim of the study was to test the hypothesis that a persistent higher level of emotional distress in schizophrenia subjects is associated with a positive family history of schizophrenia. This study used the Talbieh Brief Distress Inventory (TBDI), the Positive and Negative Syndrome Scale (PANSS; including dysphoric mood, positive and negative subscales), Montgomery-Asberg Depression Rating Scale (MADRS), and the Distress Scale for Adverse Symptoms (DSAS) to investigate the difference in the magnitude of emotional distress scores between schizophrenia subjects with and without a positive family history of schizophrenia over time. Data were recorded for 69 multiplex family and 79 singleton patients at admission and about 16 months thereafter. No between-group differences were obtained in PANSS and DSAS scores. With regard to the TBDI: (a) both group of patients had no significant differences in emotional distress scores at admission; (b) patients with negative family history reported improvement in distress severity and depression severity (MADRS) 16 months after admission, while those with positive family history experienced persistent elevated emotional distress, mainly, on obsessiveness, and depression subscales; and (c) both groups of patients are characterized by elevated emotional distress at follow-up examination compared to healthy subjects. Thus, it appears that there is a strong association between positive family history and persistent elevated emotional distress. Because patients with positive and negative family history are likely to differ in genetic risk, our results suggest that long-term elevated levels of emotional distress may be related to a familial (environmental)/genetic vulnerability to schizophrenia.  相似文献   
57.
AIM: In developed countries, there has been a recent increase in the prevalence of adenocarcinoma of the esophagus and cardia, along with a decrease in distal gastric cancers. Little is known regarding the prevalence of these diseases in developing countries. The aim of the present study was to evaluate changes in the prevalence of gastric adenocarcinomas in Turkey as a function of anatomic location. METHODS: Data were retrospectively collected from 16 centers from January 1990 to December 2000. Owing to the exclusion criteria, a total of 4065 cases of tumors of the stomach and distal esophagus were included. Tumors localized to the body, the antrum and pyloric channel were considered distal cancers. Helicobacter pylori (H. pylori) was also detected. RESULTS: Patients' mean age was 60.7 +/- 9 years, with a male : female ratio of 68:32. The ratio of distal/proximal adenocarcinoma was 2:1 for the western part of Turkey and 3:8 for the eastern part of the country (P < 0.0001), and this did not change during the 11 years. H. pylori was detected significantly less in the west compared to the east for distal tumors (65.7 vs 38.7%, respectively, P = 0.02). CONCLUSION: In Turkey, a developing country with a high H. pylori prevalence, contrary to the state of developed countries, the ratio of distal versus proximal gastric adenocarcinomas has not changed. Geographical distribution should be taken into the account in projecting the changing patterns of gastric cancers.  相似文献   
58.
BACKGROUND: N-acetylcysteine, beta-glucan, and coenzyme Q(10) were shown to have antioxidant and anti-inflammatory effects on reperfusion injury. The aim of our study was to determine and evaluate the effects of these agents on ischemia reperfusion injury of limb. MATERIAL AND METHOD: Forty-four New Zealand white rabbits, all female, weighing between 2.3 to 4.2 (mean 3.8) kg, were used in the study. Four study groups were arranged of 11 animals each, by randomization. The first group was the control group (Group C), the other groups were the Group Q, which was medicated with coenzyme Q10, the Group betaG, which was medicated with beta-glucan, and the Group N, medicated with N-acetylcysteine. After baseline measurements, for the ischemia-reperfusion experiments, common iliac artery was clamped and collateral flow was occluded by a rubber arterial tourniquet wrapped around the thigh at the proximal third of the leg. After 60 min of transient ischemic period, the limb was perfused for 180 min. After perfusion, biopsy was taken from the adductor magnus muscle. Second blood sampling was done after reperfusion period. Blood and tissue analysis were done and evaluated statistically. RESULTS: Baseline and post-reperfusion levels of glutathione peroxidase (GPx), super oxide dismutase (SOD), malonyldialdehyde (MDA), and nitric oxide (NO) changed significantly. While MDA levels increased in the control group, it decreased in the other study groups. The increase in GPx and SOD levels were significant in all groups except the control group. Levels of NO were found to have decreased in the control group, whereas it had increased in the other groups. CONCLUSION: Antioxidant medication may help lowering limb ischemia reperfusion injury. All mentioned medications in our study are shown to be able to have an effective role for preventing ischemia reperfusion injury to some extent through their antioxidant properties.  相似文献   
59.
Mycobacterium species cause a variety of clinical diseases, some of which may be species specific. Therefore, it is clinically desirable to rapidly identify and differentiate mycobacterial isolates to the species level. We developed a rapid and high-throughput system, MycoID, to identify Mycobacterium species directly from acid-fast bacillus (AFB)-positive mycobacterial culture broth. The MycoID system incorporated broad-range PCR followed by suspension array hybridization to identify 17 clinically relevant mycobacterial complexes, groups, and species in one single reaction. We evaluated a total of 271 AFB-positive culture broth specimens, which were identified by reference standard methods in combination with biochemical and molecular tests. The overall identification agreement between the standard and the MycoID system was 89.7% (perfect match) or 97.8% (one match in codetection). In comparison to the standard, the MycoID system possessed an overall sensitivity of 97.1% and specificity of 98.8%. The 159 Mycobacterium avium-M. intracellulare complex isolates were further identified to the species level by MycoID as being M. avium (n = 98; 61.1%), M. intracellulare (n = 57; 35.8%), and mixed M. avium and M. intracellulare (n = 2; 1.3%). M. avium was recovered more frequently from sterile sites than M. intracellulare (odds ratio, 4.6; P = 0.0092). The entire MycoID procedure, including specimen processing, can be completed within 5 h, providing rapid and reliable identification and differentiation of mycobacterium species that is amenable to automation. Additional differentiation of Mycobacterium avium-M. intracellulare complex strains into M. avium and M. intracellulare may provide a tool to better understand the role of Mycobacterium avium-M. intracellulare complex isolates in human disease.The increasing numbers of infections caused by mycobacteria other than tuberculosis have intensified the need for the introduction of rapid methods for isolating and identifying clinically encountered mycobacteria. The detection of pathogenic mycobacterial species continues to depend mainly on mycobacterial culture. The use of liquid culture media with continuous monitoring has significantly improved test sensitivity and test turnaround time. The Bactec mycobacterial growth indicator tube (MGIT) 960 system (Becton Dickinson Microbiology Systems, Sparks, MD), which is a fully automated, continuous-monitoring, nonradiometric, noninvasive device, is sensitive and shortens the turnaround time by 2 to 27 days (13, 25, 31).Current laboratory techniques for the identification of mycobacteria to the species level involve growth in broth, nucleic acid probing, or subculture on solid medium for phenotypic tests, which can take weeks, leading to significant delays in diagnoses. Thus, there is a need for quick and accurate identification of all mycobacteria directly from culture broth. The use of DNA probes (AccuProbe; GenProbe, San Diego, CA) that are specific for the Mycobacterium tuberculosis complex, the M. avium-M. intracellulare complex, M. kansasii, and M. gordonae directly from Bactec TB broth culture has dramatically reduced the time to identification and differentiation of mycobacterial infections (1, 6, 23). This approach, however, can identify only a limited number of mycobacterium species and requires multiple reactions. If the probe results are negative, a battery of biochemical tests must be performed with or without extracted mycolic acid analysis for definitive species identification.Several molecular methods including PCR followed by restriction fragment length polymorphism, melt curve analysis, regular sequencing, and pyrosequencing were previously reported to directly identify and differentiate mycobacterial isolates from acid-fast bacillus (AFB)-producing culture broth (15, 16, 26, 32). In this study, we report the use of a Mycobacterium genus-specific broad-range primer to amplify the partial 16S-23S rRNA gene internal transcribed spacer (ITS) region (24). After amplification, we then designed 25 mycobacterial species-specific capture oligonucleotide probes to identify and differentiate 17 commonly encountered mycobacterial species in the clinical setting by use of an xMAP suspension array system (Luminex, Austin, TX) (9). Results were validated in comparison to a reference standard using a combination of biochemical and molecular methods.(This study was presented in part at the 109th General Meeting of the American Society for Microbiology, Philadelphia, PA, 17 to 21 May 2009.)  相似文献   
60.
ObjectivesTo investigate lipid, protein, DNA oxidation and antioxidant status in blood and synovial fluid of rheumatoid arthritis (RA) patients and to determine the importance of oxidative stress parameters in reflecting disease activity.Design and methods20 RA patients and 15 healthy controls were included. Lipid peroxidation (thiobarbituric acid reactive substances (TBARS), lipid hydroperoxide, and conjugated diene), protein oxidation (carbonyl and thiol), DNA oxidation (8-OHdG) and antioxidant status markers (glutathione (GSH), glutathione peroxidase (GSH Px), superoxide dismutase (CuZn SOD), and catalase) were determined in blood and synovial fluid.ResultsTBARS (p < 0.001), lipid hydroperoxide (p < 0.001), conjugated diene (p < 0.001), carbonyl (p < 0.001) and 8-OHdG (p < 0.01) levels were significantly higher; thiol (p < 0.01) and GSH levels (p < 0.01) and GSH Px (p < 0.001) and CuZn SOD (p < 0.01) activities were significantly lower in blood of RA patients. TBARS (p < 0.001), lipid hydroperoxide (p < 0.001), conjugated diene (p < 0.01), carbonyl (p < 0.001) and 8-OHdG (p < 0.05) levels were significantly higher, catalase activity (p < 0.001) significantly lower in synovial fluid of RA patients.ConclusionsIncreased lipid, protein and DNA oxidation markers and impaired antioxidant status confirm the role of oxidative stress in the pathogenesis of RA. Lipid peroxidation markers can serve as surrogate markers for disease activity.  相似文献   
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