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排序方式: 共有794条查询结果,搜索用时 31 毫秒
1.
Abbas Pardakhty Alireza Foroumadi Mehdi Hashemi Saeed Rajabalian Mahmoud Reza Heidari 《Toxicology in vitro》2007,21(6):1031-1038
We examined the cytotoxic potential of nine N-[2-substituted-2-(2-thienyl)ethyl] piperazinyl quinolone derivatives on human oral epithelial mouth carcinoma (KB) and human squamous carcinoma (A431) cell lines. Phototoxic properties of these compounds were also evaluated by mouse 3T3 fibroblast under ultraviolet-A (UVA) irradiation. The percent of cell viability was evaluated by MTT assay. Compound 6 having a 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] group attached to N4 position of piperazine ring of enoxacin showed the highest cytotoxicity potential on both A431 and KB cell lines (IC50 of 3.11+/-0.52 and 4.91+/-1.94 microg/ml, respectively). While some of the other tested compounds exhibited clear phototoxic potential in 3T3 cell line, compound 6 showed only a minor potential of phototoxicity. These findings suggest the high potential of 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] derivative of enoxacin as a cytotoxic compound with low potency of phototoxic reactions. The mentioned chemical was identified to be of special interest for further characterization. 相似文献
2.
Khodamorad Jamshidi Abolfazl Bagherifard Hamadalla Hadi Al-Baseesee Alireza Mirzaei 《Clinical orthopaedics and related research》2021,479(5):1134
BackgroundHeterotopic ossification (HO) is common after total joint arthroplasty and usually does not cause diagnostic problems. However, the occurrence of HO after oncologic prostheses implantation can be troublesome as it may mimic a locally recurrent tumor. Because this distinction could have a profound impact on the surgeon and patient, it is important to distinguish the two entities; to our knowledge, no study has evaluated this after oncologic endoprosthetic reconstruction around the knee after tumor resection.Questions/purposes(1) How common is the occurrence of HO compared with local recurrence (LR) after resection of bone sarcoma and the use of an oncologic knee prosthesis? (2) Are there any factors associated with the development of HO after limb salvage procedures with an endoprosthesis? (3) What features allow the surgeon to differentiate HO from a locally recurrent tumor in this setting?MethodsBetween 2002 and 2018, we performed 409 resections of primary bone tumors followed by reconstructions with oncologic endoprostheses. Of these, 17% (71 of 409) died before 2 years and did not have HO at that time, 2% (8 of 409) were lost to follow-up before 2 years, and another 2% (10 of 409) did not have radiographs available at a minimum of 2 years after surgery (and had not developed HO before then), and so could not be analyzed, leaving 320 patients for analysis in this retrospective study. Forty-two patients were excluded; 2% (5 of 320) for a history of failed allograft reconstruction, 3% (8 of 320) for pathologic fracture at presentation, 2% (6 of 320) for inadequate or complicated biopsy, 1% (2 of 320) for stem fractures, 2% (7 of 320) for stem loosening, and 4% (14 of 320) for extracortical bone bridging, leaving 278 patients for final evaluation. Two observers analyzed AP and lateral radiographs for signs of HO at a mean follow-up of 63 ± 33 months after surgery. We defined HO as extraskeletal bone formation in soft tissues. The primary study endpoint was survivorship free from HO, as ascertained by a competing-risks estimator. To identify factors associated with HO appearance, the demographic, radiographic, clinical, pathologic, and surgical characteristics were compared between patients with HO and those who had no lesion. Characteristic features were also compared between patients with HO and those with LR to help their differentiation. Univariate analysis was used for all statistical evaluations.ResultsHO developed in 8% (21 of 278) of patients in whom oncologic knee prosthesis was implanted. LR developed in 10% (28 of 278) of the patients. According to survivorship estimates, the HO-free survival rate was not different from the LR-free survival rate at 2 years after oncologic knee reconstruction (76 ± 5% [95% CI 63 to 87] versus 74 ± 5% [95% CI 62 to 88]; p = 0.19). History of infection was more common in patients with HO than in patients with no lesion (19% [4 of 21] versus 5% [12 of 229], Odds ratio [OR] 6 [95% CI 2 to 17]; p < 0.001). The male sex was more common in the HO group as well (76% [16 of 21] versus 55% [128 of 229], OR 2 [95% CI 1 to 5]; p = 0.03). The Modular Universal Tumor and Revision System prosthesis was more frequently used in patients with HO (67% [14 of 21]) compared to those with no lesions (40% [92 of 229]; OR 2 [95% CI 1 to 5]; p = 0.02). The lesion border in radiographs was ill-defined in 19% (4 of 21) of patients with HO and 100% (28 of 28) of patients with LR (OR 8 [95% CI 3 to 20]; p < 0.001). The median time to the appearance of HO was shorter than the time to LR (8 months [3 to 13] versus 16 months [11 to 21], [95% CI 10 to 13]; p < 0.001). Pain at presentation was more frequent in patients with LR than in those with HO (86% [24 of 28] versus 14% [3 of 21], OR 36 [95% CI 7 to 181]; p < 0.001).ConclusionHO may occur after the use of oncologic knee prostheses for reconstruction after tumor resection. In most patients, HO could be differentiated from local recurrence through identifying a well-defined border on radiographs. Otherwise, factors such as an earlier time of presentation and absence of pain could suggest an HO, rather than an LR.Level of EvidenceLevel III, therapeutic study. 相似文献
3.
Behnam Heidari Eleonora Avenatti Khurram Nasir 《Methodist DeBakey Cardiovascular Journal》2022,18(5):5
Hypertension is one of the leading causes of disability-adjusted life years and mortality, with approximately 15% prevalence worldwide. Most patients with hypertension from low- to high-income countries do not receive treatment. Among those who receive treatment, the majority remain undertreated and do not achieve their blood pressure goals. Therefore, new hypertension guidelines introduce more conscientious treatment strategies to maximize the probability of achieving the new strict blood pressure goals compared with the previous guidelines. Who should receive treatment for hypertension? Which antihypertensive medications have the strongest supporting data? Are generic and more affordable medications as effective as expensive brand medications? What are the different treatment strategies to maximize success in controlling blood pressure? Here, we briefly review pharmacotherapy for hypertension and provide answers to these questions as well as some other common questions regarding treatment of hypertension. 相似文献
4.
Background:Embryo splitting is utilized in reproduction biotechnology. The blastomeres resulting from the splitting of an embryo in two-, four- or eight-cell stages can develop into separate embryos that are genetically similar to the other blastomeres. Aims:The present work studied the effects of splitting on embryo pluripotent gene expression (Cdx2, Sox2, Oct4, and Nanog) in mice. Methods:Two-cell embryos were isolated from stimulated mice. The embryos were grouped into “split” and “non-split” groups. The zona pellucida was removed from the split group and the blastomeres were distributed before being co-cultured with mouse embryo fibroblasts to the blastocyst stage. Normal (non-split) blastocysts were co-cultured in the same way. The 3.5-day-old blastomeres were collected as the control group. For molecular evaluation, real-time PCR was conducted to analyze changes in Cdx2, Sox2, Oct4, and Nanog gene expression. Moreover, the blastocyst formation rate, overall blastocyst rate, and the number of newborns were statistically analyzed. Results:The findings showed that embryo splitting increased blastocyst formation, overall blastocysts, developmental potential embryos, and the number of infants. Furthermore, the split and non-split (control) groups showed equal expression of pluripotent genes (Cdx2, Sox2, Oct4, and Nanog) in the molecular analysis. Conclusion:It can be concluded that the growth and developmental potency of sister blastocysts derived from split two-cell stage mouse embryos are the same as those of normal blastocysts. So, there are no significant differences in gene expression between the split and non-split groups.Key Words: Embryo splitting, Gene expression, Mouse blastocyst, Two-cell embryo 相似文献
5.
Mahin Hosseininejad Elham Mirzamohammadi Seyed Abolfazl Mohsenizadeh Saber Mohammadi 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2021,15(5):102223
AimsThe rising prevalence of metabolic syndrome has made it a major health concern. Chronic occupational exposure to organic solvents affects different systems of the body. This study aimed to investigate the association between exposure to organic solvents and the prevalence of metabolic syndrome in petroleum refinery workers.MethodThis study was conducted in 2019–2020 on workers employed in an Iranian petroleum refinery. The demographic and occupational information on the participants was obtained using the interview method. Their height, weight, and blood pressure were measured by the occupational health team, and fasting blood samples were taken from them to measure the paraclinical parameters.ResultsIn this study, 1009 petroleum refinery workers were analyzed. The prevalence of metabolic syndrome in workers was 20.1% and it was about two times higher in exposed workers (CI 95%: 1.61–3.35) compared to non-exposed ones. Factors associated with the prevalence of metabolic syndrome include age, higher BMI, exercise, and longer exposure to organic solvents.ConclusionFindings of this study suggested that exposure to organic solvents is associated with increased prevalence of metabolic syndrome (the highest association was observed with elevated serum triglycerides). Besides, longer exposure to organic solvents increased the risk of developing metabolic syndrome. 相似文献
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Shima Farahani Navid Eshghi Abolfazl Abbasi Fereshteh Karimi Ebadallah Shiri Malekabad 《Toxin reviews》2015,34(2):96-100
Increase of distribution of environmental contaminants such as heavy metals have been caused the knowledge of the safety and hygiene of food is very important, especially eggs, because of its role in the daily diet. There are very few studies about the investigation of the heavy metal contents in egg-white. In this study, six heavy metals include Aluminium (Al), Arsenic (As), Lead (Pb), Cadmium (Cd), Mercury (Hg), Antimony (Sb) in egg-white from 32 industrial poultry farms were investigated, by ICP-OES. All the samples were collected in all area of Markazi Province, Iran in autumn 2013. The mean concentrations of heavy metals in egg-white as follows: 0.119 for Al, 0.785 for As, 0.750 for Pb, 0.249 for Cd, 0.270 for Hg and 0.186?mg/kg for Sb. Also, the concentration of the some heavy metals were higher than maximum allowable concentration that probably it is associated to use pesticides and activities of industrial factories around the poultry farms. 相似文献
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10.
Reza Heidari Akram Jamshidzadeh Nahid Keshavarz Negar Azarpira 《Scientia pharmaceutica》2015,83(1):143-158
Methimazole is the most widely prescribed antithyroid medication in humans. However, hepatotoxicity is a deleterious adverse effect associated with methimazole administration. No specific protective agent has been developed against this complication yet. This study was designed to investigate the role of taurine as a hepatoprotective agent against methimazole-induced liver injury in mice. Different reactive metabolites were proposed to be responsible for methimazole hepatotoxicity. Hence, methimazole-induced liver injury was investigated in intact and/or enzyme-induced animals in the current investigation. Animals were treated with methimazole (200 mg/kg, by gavage), and hepatic injury induced by this drug was investigated in intact and/or enzyme-induced groups. Markers such as lipid peroxidation, hepatic glutathione content, alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in plasma, and histopathological changes in the liver of animals were monitored after drug administration. Methimazole caused liver injury as revealed by increased plasma ALT. Furthermore, a significant amount of lipid peroxidation was detected in the drug-treated animals, and hepatic glutathione reservoirs were depleted. Methimazole-induced hepatotoxicity was more severe in enzyme-induced mice. The above-mentioned alterations in hepatotoxicity markers were endorsed by significant histopathological changes in the liver. Taurine administration (1 g/kg, i.p.) effectively alleviated methimazole-induced liver injury in both intact and/or enzyme-induced animals. 相似文献