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排序方式: 共有378条查询结果,搜索用时 203 毫秒
331.
Colakoglu N Kukner A Oner J Sonmez MF Oner H Ozan E 《Journal of molecular histology》2005,36(6-7):413-418
Summary The aim of this study was to investigate the effects of excess all-trans retinoic acid, a vitamin A metabolite, on pancreatic organogenesis and TGF-β2 expression during prenatal development in rats.First group of animals used as control while a single dose of 60 mg/kg all-trans retinoic acid was ingested by the mothers, at day 8 of gestation (before the neurulation period) in group II and at day 12 of gestation (after the neurulation period) in group III, and all embryos were sacrificed at day 18 of gestation. TGF-β2 expression was detected in the capsule, acini and Langerhans islets in the control group. In the pancreas of group II, dilatation and congestion of interlobular vessels were observed. Langerhans islet structures were completely absent. Moreover acinar TGF-β2 immune reactivity was not determined. In group III, acinar expression of TGF-β2 in acid was similar to that in the controls but their Langerhans islets TGF-β2 immune reactivity was significantly less than the controls.In view of the present findings we suggest that TGF-β2 plays important role in pancreatic morphogenesis and administration of excess all-trans retinoic acid before neurulation inhibit TGF-β2 expression disrupted pancreatic morphogenesis particularly Langerhans islets. However, its administration after neurulation had less adverse affect on pancreatic organogenesis and TGF-β2 immune reactivity. 相似文献
332.
Plasma xanthine oxidase, superoxide dismutase and glutathione peroxidase activities and uric acid levels in severe and mild pre-eclampsia 总被引:2,自引:0,他引:2
Yildirim A Altinkaynak K Aksoy H Sahin YN Akcay F 《Cell biochemistry and function》2004,22(4):213-217
The aim of the present study was to measure plasma uric acid (UA) levels and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and xanthine oxidase (XO) activities and to evaluate the relationship between these parameters and the severity of pre-eclampsia. Twenty-five pre-eclamptic, 15 healthy pregnant and 15 non-pregnant women were enrolled in this study. Increased mean plasma XO activity was found to be higher in both pre-eclampsia groups than in the healthy pregnant group. Plasma UA levels were the highest in the severe pre-eclampsia group among the study groups. SOD and GSH-Px activities were significantly lower in both pre-eclampsia groups than in the healthy pregnant group (p < 0.005 and p < 0.001, respectively). Increased XO and decreased SOD and GSH-Px activities may contribute to the pathophysiological mechanisms of pre-eclampsia and increased UA may serve a protective role responding to superoxide radicals arising from increased XO activity or other sources in pre-eclampsia. 相似文献
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Gökalp İşcan Neşe Kırımer Fatih Demirci Betül Demirci Yoshiaki Noma K. Hüsnü Can Başer 《化学与生物多样性》2012,9(8):1525-1532
Terpene derivatives converted by microbial biotransformation constitute an important resource for natural pharmaceutical, fragrance, and aroma substances. In the present study, the monoterpene α‐phellandrene was biotransformed by 16 different strains of microorganisms (bacteria, fungi, and yeasts). The transformation metabolites were initially screened by TLC and GC/MS, and then further characterized by NMR spectroscopic techniques. Among the six metabolites characterized, 6‐hydroxypiperitone, α‐phellandrene epoxide, cis‐p‐menth‐2‐en‐1‐ol, and carvotanacetone, which originated from (?)‐(R)‐α‐phellandrene, are reported for the first time in this study. Additionally, the substrate and the metabolite 5‐p‐menthene‐1,2‐diol were subjected to in vitro antibacterial and anticandidal tests. The metabolite showed moderate‐to‐good inhibitory activities (MICs=0.125 to >4 mg/ml) against various bacteria and especially against Candida species in comparison with its substrate (?)‐(R)‐α‐phellandrene and standard antimicrobial agents. 相似文献
335.
Matthijs van der Knaap Fatih Basalan Henny C. van de Mei Henk J. Busscher Gijsbert A. van der Marel Herman S. Overkleeft Mark Overhand 《化学与生物多样性》2012,9(11):2494-2506
Via a Mannich reaction involving a dibenzyliminium species and the titanium enolates of Evans' chiral acylated oxazolidinones the β2‐amino acids (R)‐ and (S)‐Fmoc‐β2homovaline and (R)‐Fmoc‐β2homoleucine are synthesized. These building blocks were used, in combination with commercially available α‐ and β3‐amino acids, for the synthesis of the cyclo‐(αβ3αβ2α)2 peptide 2 and the cyclo‐(αβ2αβ3α)2 peptides 3 – 5 . The peptides 2 – 5 were screened for their ability to inhibit a small panel of Gram‐negative and Gram‐positive bacterial strains. 相似文献
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The complexity of neurons and neuronal circuits in brain tissue requires the genetic manipulation, labeling, and tracking of single cells. However, current methods for manipulating cells in brain tissue are limited to either bulk techniques, lacking single-cell accuracy, or manual methods that provide single-cell accuracy but at significantly lower throughputs and repeatability. Here, we demonstrate high-throughput, efficient, reliable, and combinatorial delivery of multiple genetic vectors and reagents into targeted cells within the same tissue sample with single-cell accuracy. Our system automatically loads nanoliter-scale volumes of reagents into a micropipette from multiwell plates, targets and transfects single cells in brain tissues using a robust electroporation technique, and finally preps the micropipette by automated cleaning for repeating the transfection cycle. We demonstrate multi-colored labeling of adjacent cells, both in organotypic and acute slices, and transfection of plasmids encoding different protein isoforms into neurons within the same brain tissue for analysis of their effects on linear dendritic spine density. Our platform could also be used to rapidly deliver, both ex vivo and in vivo, a variety of genetic vectors, including optogenetic and cell-type specific agents, as well as fast-acting reagents such as labeling dyes, calcium sensors, and voltage sensors to manipulate and track neuronal circuit activity at single-cell resolution. 相似文献
338.
Coskun Silan Omer Tamer Dogan Fatma Silan Fatma Mutlu Kukulguven Halil Fatih Asgun Semra Ozdemir Ahmet Uludag Sinem Atik Buket Gungor Se?il Akdur Hakki Engin Aksulu Oztürk Ozdemir 《Molecular biology reports》2012,39(12):11017-11022
The aim was to investigate the prevalence of VKORC1 and CYP2C9 genotypes in patients requiring anticoagulant therapy in two different region’s populations of Turkey. The recent cohort included 292 patients that needed anticoagulant therapy, and who had a history of deep vein thrombosis and/or pulmonary artery thromboembolism. Genomic DNA was isolated from peripheral blood samples and the StripAssay reverse hybridization or Real Time PCR technique was used for genotype analysis. Genotypes for CYP2C9 were detected as follows: 165 (56.5?%) for CYP2C9*1/*1, 67 (23.0?%) for CYP2C9*1/*2, 25 (8.6?%) for CYP2C9*1/*3, 9 (3.0?%) for CYP2C9*2/*2, 21 (7.2?%) for CYP2C9*2/*3, 5(1.7?%) for CYP2C9*3/*3 for CYP2C9 and the allele frequencies were: 0.723 for allele*1, 0.182 for allele*2 and 0.095 for allele*3 respectively. Genotypes for VKORC1 were detected as follows: 64 (21.9?%) for GG, 220 (75.4?%) for GA and 8 (2.7?%) for AA alleles. The G allele frequency was detected as 0.596, and the A allele frequency was 0.404. The VKORC1 1639 G>A and CYP2C9 mutation prevalence and allele frequency of the current results from two different populations (Sivas and Canakkale) showed similarly very variable profiles when compared to the other results from the Turkish population. 相似文献
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