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排序方式: 共有1638条查询结果,搜索用时 15 毫秒
1.
Kalbolandi Sanaz Moradi Gorji Armita Valizadeh Babaahmadi-Rezaei Hossein Mansouri Esrafil 《Molecular biology reports》2019,46(4):4039-4047
Molecular Biology Reports - This work aims to evaluate the renoprotective effect of luteolin on expression of Nrf2 and miR320 in ischemia–reperfusion (I/R) injury in rats. Thirty rats were... 相似文献
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Cryptococcus neoformans was instilled intranasally into mice which were periodically sacrificed to determine the course of infection. Cryptococci persisted within the nasal passages throughout the 90 day study. Extranasal dissemination began 14–28 days after instillation and was still demonstrable 90 days post-exposure. Ten percent mortality was observed in mice receiving 106 cryptococci, while no mortality was observed in mice exposed to 103 or 104 cryptococci. Our research suggests that nasal colonization with C. neoformans can precede pulmonary and systemic cryptococcosis by weeks or months. 相似文献
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The effect of Cl−, HCO3−, Br−, acetazolamide, thiocyanate and amiloride on urine formation in Locusta migratoria Malpighian tubules have been determined. The rate of fluid secretion depends markedly on the concentration of Cl− in the bathing solution with concentrations less than 90 mM resulting in reduced fluid secretion. Substitution of Br− for Cl− had no significant effect on the rate of the fluid secretion. Replacement of NaHCO3 with NaCl in Hepes buffered Ringer solution reduced the rate of urine production by 23%. Fluid secretions were reduced in the presence of 10−4–10−2 M acetazolamide, a carbonic anhydrase inhibitor. The combined effect of acetazolamide in the absence of HCO3− appears to be additive. A 1 mM concentration of thiocyanate, an ionic inhibitor, reduced fluid secretion by 35%. Amiloride interferes with the electrogenic entry of Na+ into the cell and a 1 mM solution reduced fluid secretion by 94% with secretion completely inhibited in 80% of the tubules tested. 相似文献
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The objective of this study was to examine membrane filtration of a single stranded DNA (ssDNA) with 60 thymine nucleotides, and to elucidate the variables controlling its transmission across track-etched porous membranes. Dead end filtration measurements were performed using different pore size membranes (10, 15, and 30 nm) at different transmembrane pressures in solutions with ionic strength ranging from 0 to 1000 mM NaCl. The diffusivity of the ssDNA was determined using fluorescence recovery after photobleaching, yielding hydrodynamic radii ranging from 1.6 to 2.8 nm, with values decreasing with increasing solution ionic strength. Despite the small ssDNA/membrane pore size, nearly 100% rejection was observed for measurements performed with the 10 and 15 nm pore size membranes under low-ionic strength conditions. These high rejections can be attributed to strong repulsive electrostatic ssDNA-membrane interactions. With increasing ionic strength, electrostatic interactions as well as the effective size of the ssDNA decreases and the flexibility of the ssDNA increases, leading to a reduction in ssDNA rejection. A design of experiments approach was used to plan filtration experiments that adequately covered the variable space with a manageable number of experiments. The results yielded an empirical expression relating ssDNA rejection to pore size, solution ionic strength and transmembrane pressure. There was evidence of flow induced elongation at high-transmembrane pressures in the 30 nm pore size membranes, but not in the smaller pore size membranes. These results are consistent with critical flux estimates developed using a free draining model for the ssDNA. 相似文献
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Hadi Shahrabadi Amir Hossein Haghighi Roya Askari Majid Asadi-Shekaari Daniel Costa Souza Paulo Gentil 《Current issues in molecular biology》2022,44(7):3030
Chronic methamphetamine use increases apoptosis, leading to heart failure and sudden cardiac death. Previous studies have shown the importance of high-intensity interval training (HIIT) in reducing indices of cardiac tissue apoptosis in different patients, but in the field of sports science, the molecular mechanisms of apoptosis in methamphetamine-dependent rats are still unclear. The present article aimed to investigate the changes in cardiac apoptosis markers in methamphetamine-dependent rats in response to HIIT. Left ventricular tissue was used to evaluate caspase-3, melusin, FAK, and IQGAP1 gene expression. Rats were divided into four groups: sham, methamphetamine (METH), METH-control, and METH-HIIT. METH was injected for 21 days and then the METH-HIIT group performed HIIT for 8 weeks at 5 sessions per week. The METH groups showed increased caspase-3 gene expression and decreased melusin, FAK, and IQGAP1 when compared to the sham group. METH-HIIT showed decreased caspase-3 and increased melusin and FAK gene expression compared with the METH and METH-control groups. The IQGAP1 gene was higher in METH-HIIT when compared with METH, while no difference was observed between METH-HIIT and METH-control. Twenty-one days of METH exposure increased apoptosis markers in rat cardiac tissue; however, HIIT might have a protective effect, as shown by the apoptosis markers. 相似文献
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Zahra Fazeli Mir Davood Omrani Sayyed Mohammad Hossein Ghaderian 《Journal of cell communication and signaling》2016,10(4):273-282
Different signaling pathways are implicated in proliferation and differentiation of stem cells. Bone Morphogenesis Pathway (BMP) signaling was known to display an important function in osteogenic and adipogenic differentiation of mesenchymal stem cells (MSCs). In the present study, the authors investigated whether blocking BMP signaling was associated with down regulation of Nestin expression as neural stem cell marker in peripheral blood derived mesenchymal stem cells (PB-MSCs). At first, MSCs were isolated from peripheral blood by plastic adherent ability and flow cytometry analysis. After reaching the confluence, the cells were treated with medium containing Noggin as antagonist of BMP signaling upon 8 days. Real time PCR analysis indicated that the expression of Nestin was diminished in PB-MSCs by attenuating BMP signaling. The obtained results suggested that BMP signaling might have a regulatory function on the Nestin expression in mesenchymal stem cells. 相似文献
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Abdolkarim Moazeni-Roodi Saeid Ghavami Hossein Ansari Mohammad Hashemi 《Journal of cellular biochemistry》2019,120(8):13583-13597
Flap endonuclease 1 (FEN1) has emerged as an important enzyme in the maintenance of genomic instability and preventing carcinogenesis. The relationship between FEN1 −69G>A (rs174538)+4150G>T (rs4246215) polymorphisms and cancer susceptibility has been reported; however, results were inconclusive. In the present study, a meta-analysis of data from eligible reports was carried out to summarize the possible relationship between FEN1 polymorphisms and cancer risk. A total of 11 articles, including 20 studies with 7366 cases and 9028 controls and 18 studies with 6649 cases and 8325 controls for FEN1 rs174538 and FEN1 rs4246215 polymorphisms, respectively, were recruited for meta-analysis. Overall, meta-analyses showed that FEN1 rs174538 and rs4246215 polymorphisms are significantly associated with the decreased risk of cancer. The stratified analysis proposed that both variants were associated with protection against gastrointestinal cancer, breast cancer, hepatocellular cancer, esophageal cancer, gastric cancer, colorectal cancer, and lung cancer. In conclusion, this meta-analysis revealed an association between FEN1 polymorphisms and cancer risk. Additional studies in a larger study population that include subjects from a variety of ethnicities are warranted to further verify our findings. 相似文献