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排序方式: 共有1102条查询结果,搜索用时 15 毫秒
81.
Johansson S Fuchs A Okvist A Karimi M Harper C Garrick T Sheedy D Hurd Y Bakalkin G Ekström TJ 《Brain research》2007,1132(1):20-28
Real-time PCR is frequently used for gene expression quantification due to its methodological sensitivity and reproducibility. The gene expression is quantified by normalization to one or more reference genes, usually beta-actin (ACTB), glyceraldehyde-3-phosphate dehydrogenase (GAPD) or to ribosomal RNA (18S). However, different environmental or pathological conditions might also influence the expression of normalizing genes, which could severely skew the interpretation of quantitative results. This study evaluates whether 16 genes frequently used as endogenous controls in expression studies, can serve as such for comparison of human brain tissues of chronic alcoholics and control subjects. The prefrontal and motor cortices that are affected differently by chronic alcohol consumption were analyzed. The reference genes that have no or small differences in expression in alcoholics and control subjects, were found to be specific for each region: beta-actin (ACTB) and ribosomal large P0 (RPLP0) for the prefrontal cortex while importin 8 (IPO8) and RNA polymerase II (POLR2A) for the motor cortex. Four out of sixteen analyzed genes demonstrated significant differences in expression between alcoholics and controls: phosphoglycerate kinase (PGK1), hypoxanthine phosphoribosyl transferase (HPRT1) and peptidylprolyl isomerase A (PPIA) in the motor cortex and beta-2-microglobulin (B2M) in the prefrontal cortex. Our study demonstrates the importance of validation of endogenous control genes prior to real-time PCR analysis of human brain tissues. Prescribed and non-prescribed drugs, pathological or environmental conditions along with alcohol abuse may differentially influence expression of reference genes. 相似文献
82.
Left ventricular (LV) failure is the main cause of death in thalassemia. Iron overload in patients with thalassemia leads to the formation of oxygen free radicals. Of the various apolipoprotein E (apoE) alleles, apoE4 is the least efficient in conditions of oxidative stress in comparison with apoE2 and apoE3. Our results showed that apoE4 is a genetic risk factor for LV dysfunction in thalassemia. 相似文献
83.
One-week versus two-week furazolidone-based quadruple therapy as the first-line treatment for Helicobacter pylori infection in Iran 总被引:3,自引:0,他引:3
Daghaghzadeh H Emami MH Karimi S Raeisi M 《Journal of gastroenterology and hepatology》2007,22(9):1399-1403
Background and Aim: Furazolidone‐based regimens for the eradication of Helicobacter pylori are low cost and effective although less tolerable. Our aim was to compare the efficacy and compliance of 1‐week furazolidone‐based quadruple therapy (furazolidone, amoxicillin, bismuth subcitrate, omeprazole; FABO) with 2‐week quadruple therapy using the same drugs. Methods: One hundred and fifty‐six consecutive patients with H. pylori related diseases were enrolled in our study. The patients were randomized into two groups of FABO1 and FABO2 groups receiving, 1 or 2 weeks' quadruple H. pylori eradication therapies, respectively, as follows: furazolidone (200 mg twice daily), amoxicillin (1 g twice daily), bismuth (240 mg twice daily) and omeprazole (20 mg twice daily). The χ2 test was used to compare the efficacy of the therapies. Results: The per‐protocol eradication rate in FABO1 and FABO2 groups were 56/66 (84.8%) and 57/69 (82.6%), respectively. The intention‐to‐treat eradication rate was 56/78 (71.8%) in FABO1 group and 57/78 (73.1%) in FABO2 group. There was not any significant statistical difference between two groups. A significant decrease in compliance in FABO2 group was seen. Conclusion: This is an encouraging report showing a therapy with possible success in decreasing the duration of H. pylori infection as well as reaching the eradication rate of 80%. 相似文献
84.
SUMMARY: A 60-year-old woman developed right-eye vision loss secondary to rhinocerebral mucormycosis. Routine MR imaging sequences including enhanced MR imaging showed normal optic nerves, but a diffusion-weighted sequence and apparent diffusion coefficient maps revealed markedly restricted diffusion in the right optic nerve. This MR imaging abnormality of optic nerve infarction due to mucormycosis has not been reported previously. 相似文献
85.
Peter C Kielstein JT Clarke-Katzenberg R Adams MC Pitsiouni M Kambham N Karimi MA Kengatharan KM Cooke JP 《The Journal of urology》2007,177(6):2342-2346
PURPOSE: Bioluminescent imaging permits sensitive in vivo detection and quantification of cells engineered to emit light. We developed a bioluminescent human renal cancer cell line for in vitro and in vivo studies. MATERIAL AND METHODS: The 2 human renal cell carcinoma cell lines SN12-C and SN12-L1 were stably transfected to constitutively express luciferase using a retroviral shuttle. The bioluminescent signal was correlated with tumor cell numbers in vitro. Parental and transfected cells were compared by growth kinetics and histology. Tumor burden after heterotopic injection in immune deficient mice was monitored up to 39 days. The kinetics of the bioluminescent signal was evaluated for 1 to 60 minutes following luciferin injection. RESULTS: Bioengineered renal cancer cell lines stably expressed luciferase. The growth kinetics of the cells in vitro and the histology of tumors resulting from implantation of these cells were unaffected by retroviral transfection with the luciferase gene. As few as 1,000 cells could be reliably detected. The intensity of the bioluminescent signal correlated with the number of tumor cells in vitro. Photon emission in vivo and ex vivo correlated significantly with tumor weight at sacrifice. After intraperitoneal injection of luciferin there was a time dependent change in the intensity of the bioluminescent signal with maximum photon emission at 20 minutes (optimal 17 to 25). CONCLUSIONS: Luciferase transfected human renal cancer lines allow reliable, rapid, noninvasive and longitudinal monitoring of tumor growth in vivo. The ability to assess tumor development in vivo with time is economical and effective compared to end point data experiments. 相似文献
86.
Heart complications are among the serious problems of patients with β-thalassemia intermedia. This study aimed to evaluate
myocardial function in these patients. Clinical parameters and both standard Doppler and pulsed Doppler tissue imaging parameters
were compared in 51 β-thalassemia intermedia patients (mean age, 17.05 ± 5.8 years) and 20 normal subjects (mean age, 17.81 ± 7.35 years,
p = 0.98). In 11 patients (21.5%), pulmonary artery hypertension was detected. M-mode echocardiographic findings such as ejection
fraction and fractional shortening did not show statistically significant changes (p > 0.005). Pulsed Doppler showed a significant difference in the early (E) to late diastolic (A) velocity ratio of the tricuspid
and mitral valve between the patients and the control subjects (p < 0.05). In the pulsed tissue Doppler study, the peak systolic velocity of the septum (Ss), the peak atrial velocity of the
septum (Aas), the peak systolic velocity of the tricuspid annulus (St), the peak early diastolic velocity of the tricuspid
annulus (Eat), and the peak late diastolic velocity of the tricuspid annulus (Aat) were increased significantly (p < 0.05). The pulse tissue Doppler of the lateral mitral annulus did not change significantly (p > 0.005). The peak systolic velocity of the posterior wall and the peak late diastolic velocity of the anterior wall changed
significantly (p < 0.05). This study showed that β-thalassemia intermedia patients with normal M-mode and two-dimensional echocardiography
had statistically significant changes in pulsed Doppler and pulsed tissue Doppler imaging. 相似文献
87.
Karimi Saeed Nikkhah Homayoun Farzanbakhsh Shayan Karjou Zahra Safi Sare 《International ophthalmology》2022,42(7):2267-2272
International Ophthalmology - To evaluate the outcomes and complications of simultaneous silicon oil removal (SOR) and phacoemulsification and intra ocular lens implantation. In this retrospective... 相似文献
88.
89.
Combination of fluticasone propionate and salmeterol potentiates the suppression of cigarette smoke-induced IL-8 production by macrophages 总被引:1,自引:1,他引:0
Sarir H Mortaz E Karimi K Johnson M Nijkamp FP Folkerts G 《European journal of pharmacology》2007,571(1):55-61
Cigarette smoke is the major risk factor for the development of chronic obstructive pulmonary disease (COPD). Macrophages are suggested to orchestrate the chronic inflammatory response and tissue destruction associated with COPD by secreting interleukin (IL)-8, a major neutrophil chemoattractant. The combination of inhaled corticosteroids and long-acting beta(2)-adrenoceptor agonists are increasingly used as maintenance therapy in patients with COPD. The aim of this study was to determine whether combined fluticasone propionate, a corticosteroid, and salmeterol, a long-acting beta(2)-adrenoceptor agonist, can suppress IL-8 production by human macrophages. To mimic resident macrophages in the lung, human monocytes were cultured for 5 days in medium containing Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) and Macrophage Colony Stimulating Factor (M-CSF). In human Monocyte-Derived Macrophages, we found that cigarette smoke medium strongly enhanced IL-8 release in a time- and concentration-dependent manner. IL-8 release by cigarette smoke was significantly suppressed in a concentration-dependent manner by fluticasone and salmeterol. Coincubation of the drugs potentiated the inhibitory effect on cigarette smoke medium-induced IL-8 production and longer preincubation times resulted in more IL-8 inhibition. Interestingly, preincubation of cells with suboptimal concentration of salmeterol for 4 h before fluticasone administration for 30 min potentiates the inhibitory effect of fluticasone on IL-8 release. In conclusion, combination therapy may provide benefits over monotherapy for the treatment of COPD patients. 相似文献
90.
James K. Min Reza Arsanjani Sachio Kurabayashi Daniele Andreini Gianluca Pontone Byung-Wook Choi Hyuk-Jae Chang Bin Lu Jagat Narula Afshin Karimi Carl Roobottom Millie Gomez Daniel S. Berman Ricardo C. Cury Todd Villines Joon Kang Jonathon Leipsic 《Journal of Cardiovascular Computed Tomography》2013,7(3):200-206
BackgroundCoronary CT angiography (CTA) has emerged as an effective noninvasive method for direct visualization of the coronary arteries, with high diagnostic performance compared with invasive coronary angiography (ICA). However, coronary CTA is prone to artifacts, including coronary motion, which may reduce its diagnostic performance. Intracycle motion compensation algorithms (MCAs) from a combination of software and hardware techniques now allow for correction of coronary motion, but the diagnostic performance of MCAs compared with traditional coronary CTA reconstruction methods remains unexplored.MethodsViCTORY (Validation of an Intracycle CT Motion CORrection Algorithm for Diagnostic AccuracY) is a prospective international multicenter trial of 218 patients which is designed to evaluate the performance of MCAs for the diagnosis of anatomically obstructive coronary artery disease (CAD) compared with an ICA reference standard, on a per-patient, per-vessel, and per-segment basis. Patients enrolled into ViCTORY will undergo investigational coronary CTA and clinically indicated ICA and will not receive heart rate-lowering medications before coronary CTA. Coronary CTA images will be reconstructed by conventional standard methods as well as by MCAs. Blinded core laboratory interpretation will be performed for coronary CTA and ICA in an intent-to-diagnose fashion.ResultsThe primary end point of ViCTORY is the per-patient diagnostic accuracy of MCAs for the diagnosis of anatomically obstructive CAD compared with ICA. Secondary end points will include other per-patient, per-vessel, and per-segment diagnostic performance characteristics, including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value. Other key secondary end points will include diagnostic interpretability, image quality, the upper heart rate threshold of utility of MCAs, and the additive value of MCAs to traditionally reconstructed coronary CTA.ConclusionViCTORY will determine whether MCAs improve the diagnosis of obstructive CAD in patients undergoing coronary CTA who are not receiving heart rate-lowering medications. 相似文献