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排序方式: 共有1470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
2.
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
3.
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
4.
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
5.
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
6.
In vitro improvement of quail primordial germ cell expansion through activation of TGF‐beta signaling pathway 下载免费PDF全文
7.
Marzieh Taghipour Shamsollah Ayoubi Hossein Khademi 《Soil & Sediment Contamination》2011,20(8):921-937
Heavy metals’ origin, accumulation, and distribution in soil have been the focus of much attention by many researchers. The objective of this study was to recognize the sources of heavy metals in surface soils in Hamadan Province in western Iran using multivariate geostatistical techniques. A total of 263 surface (0–10 cm) soil samples and 18 rock samples from major parent materials were collected. Cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn) contents of the samples were determined. Selected soil physical and chemical characteristics were also measured. A multivariate geostatistical analysis was performed to identify the common source of heavy metals. The quantities of Co, Cr, and Ni were found to be associated with parent rocks, corresponding to the first factor termed the “lithologic component.” The second factor was mainly attributed to Cu, which also comprised the first and third factors, indicating a mixed source both from lithologic and anthropogenic inputs. Zn and Pb contents were related to the anthropogenic activities and comprised the third factor. A significant correlation was found between metals from the lithogenic sources and selected soil properties such as soil organic matter, clay, CEC, and carbonate, indicating an interaction among them. Generally, Zn and Pb showed a less significant correlation with soil properties. 相似文献
8.
Omid Haghighi Soheila Davaeifar Hossein Shahbani Zahiri Hadi Maleki Kambiz Akbari Noghabi 《International journal of peptide research and therapeutics》2020,26(2):783-793
Glutamate dehydrogenase (GDH), which is present in most bacteria and eukaryotes’ mitochondria, plays an important role in amino acid metabolism. In g 相似文献
9.
Effect of Drought Stress on Certain Morphological and Physiological Characteristics of a Resistant and a Sensitive Canola Cultivar 总被引:1,自引:0,他引:1
Ghorban Khodabin Zeinolabedin Tahmasebi‐Sarvestani Amir Hossein Shirani Rad Seyed Ali Mohammad Modarres‐Sanavy 《化学与生物多样性》2020,17(2)
Water stress is one of the main abiotic factors that reduces plant growth, mainly due to high evaporative demand and low water availability. In order to evaluate the effects of drought stress on certain morphological and physiological characteristics of two canola cultivars, we conducted a factorial experiment based on a completely randomized design. The findings show that drought stress exacerbations result in the plant's response to stress due to increased canola resistance caused by changes in plant pigments, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase and malondialdehyde, glucose, galactose, rhamnose and xylose. These in turn ultimately influence the morphological characteristics of canola. Drought stress reduces the concentration of carotenoids, chlorophyll a, chlorophyll b, total chlorophylls; however, glucose, galactose, rhamnose, xylose, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase, malondialdehyde (in leaves and roots) and the chlorophyll a and b ratios were increased. Reduction of plant height, stem height, root length, fresh and dry weight of canola treated with 300 g/l PEG compared to non‐treatment were 0.264, 0.236, 0.394, 0.183 and 0.395, respectively. From the two canola cultivars, the morphological characteristics of the NIMA increased compared to the Ks7 cultivar. Interaction effects of cultivar and drought stress showed that NIMA cultivar without treatment had the highest number of morphological characteristics such as carotenoid concentration, chlorophyll a, chlorophyll b, total chlorophylls a and b, whereas the cultivar with 300 g/l PEG (drought stress) had the highest amount of proline, malondialdehyde, soluble sugars and enzymes in leaves and roots. Increasing activity of oxidative enzymes and soluble sugars in canola under drought stress could be a sign of their relative tolerance to drought stress. 相似文献
10.
Foroughi Kobra Jahanbani Sarvin Nazarnezhad Simin Khastar Hossein Jafarisani Moslem Tashakori Mersedeh Kazemi Seyedeh Sareh 《International journal of peptide research and therapeutics》2020,26(2):1115-1126
International Journal of Peptide Research and Therapeutics - Survivin is a unique member of the inhibitor of apoptosis protein family. Research has approved Survivin’s ability to interact... 相似文献