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31.
Iwona Żur Andrzej Skoczowski Sebastian Pieńkowski Franciszek Dubert 《Acta Physiologiae Plantarum》2002,24(1):11-17
The uptake rate of 14C-labelled sucrose, myo-inositol and PC was studied in callus cultures of two oilseed rape cultivars, characterized by different in vitro regeneration ability. Transfer of calli onto regeneration stimulating medium resulted in changes of examined substances uptake
rate, which were depended on tissue morphogenic potential. Non-regenerating calli of both cultivars increased uptake rate
of sucrose whereas changes in incorporation of other compounds were under genome control. Significant increase of uptake rate
of all tested compounds was observed as result of organogenesis initiation. Such differences, in the responses of organogenic
and non-organogenic tissue indicate that this parameter could be useful as marker of organogenesis
A correlation was observed between the rate of sucrose uptake and its concentration in the medium, which suggests an advantage
to passive transport through the callus cell membrane. Lack of such correlation in the case of other labels indicates that
this processes are selective and under cell control. 相似文献
32.
Żur Iwona Skoczowski Andrzej Niemczyk Elżbieta Dubert Franciszek 《Acta Physiologiae Plantarum》2002,24(1):3-10
Changes in the membrane lipid and sterols content and composition were studied during induction and differentiation in callus
cultures of Brassica napus var. oleifera. Callus induction was associated with an increase of DGDG content, significant changes in fatty acids composition of all
lipid fractions and increased degree of lipid unsaturation. The membrane lipid composition of tissue at different degrees
of differentiation was found to vary significantly, particularly two weeks after transfer of callus to regeneration medium.
The main differences concerned the content and composition of galactolipids. Curiously in many cases, these differences declined
during subsequent culture, in spite of the morphogenesis process which was in progress. Another result of differentiation
was the change in free sterol composition: in shoot regenerating calli the content of stigmasterol had rose whereas the accumulation
of campesterol decreased. Even though observed changes in membrane properties may not play a role in morphogenesis they are
nevertheless useful as developmental markers and can be invaluable in understanding biochemical basis of morphogenesis. 相似文献
33.
Objective To determine the relation between intake of seafood in pregnancy and risk of preterm delivery and low birth weight.DesignProspective cohort study.Setting Aarhus, Denmark.Participants8729 pregnant women.Results The occurrence of preterm delivery differed significantly across four groups of seafood intake, falling progressively from 7.1% in the group never consuming fish to 1.9% in the group consuming fish as a hot meal and an open sandwich with fish at least once a week. Adjusted odds for preterm delivery were increased by a factor of 3.6 (95% confidence interval 1.2 to 11.2) in the zero consumption group compared with the highest consumption group. Analyses based on quantified intakes indicated that the working range of the dose-response relation is mainly from zero intake up to a daily intake of 15 g fish or 0.15 g n-3 fatty acids. Estimates of risk for low birth weight were similar to those for preterm delivery.Conclusions Low consumption of fish was a strong risk factor for preterm delivery and low birth weight. In women with zero or low intake of fish, small amounts of n-3 fatty acids—provided as fish or fish oil—may confer protection against preterm delivery and low birth weight.
What is already known on this topic
Long chain n-3 fatty acids in amounts above 2 g a day may delay spontaneous delivery and prevent recurrence of preterm deliveryLarge studies have not been carried out to determine to what extent low consumption of n-3 fatty acids is a risk factor for preterm deliveryThe dose-response relation has not been describedWhat this study adds
Low consumption of fish seems to be a strong risk factor for preterm delivery and low birth weight in Danish womenThis relation is strongest below an estimated daily intake of 0.15 g long chain n-3 fatty acids or 15 g fish 相似文献34.
Milan Ivanov Nevena Mihailovi?-Stanojevi? Jelica Gruji? Milanovi? ?ur?ica Jovovi? Jasmina Markovi?-Lipkovski Sanja ?irovi? Zoran Miloradovi? 《PloS one》2014,9(5)
Ischemic acute renal failure (ARF) is a highly complex disorder involving renal vasoconstriction, filtration failure, tubular obstruction, tubular backleak and generation of reactive oxygen species. Due to this complexity, the aim of our study was to explore effects of Angiotensin II type 1 receptor (AT1R) blockade on kidney structure and function, as well as oxidative stress in spontaneously hypertensive rats (SHR) after renal ischemia reperfusion injury. Experiments were performed on anaesthetized adult male SHR in the model of ARF with 40 minutes clamping the left renal artery. The right kidney was removed and 40 minutes renal ischemia was performed. Experimental groups received AT1R antagonist (Losartan) or vehicle (saline) in the femoral vein 5 minutes before, during and 175 minutes after the period of ischemia. Biochemical parameters were measured and kidney specimens were collected 24h after reperfusion. ARF significantly decreased creatinine and urea clearance, increased LDL and lipid peroxidation in plasma. Treatment with losartan induced a significant increase of creatinine and urea clearance, as well as HDL. Lipid peroxidation in plasma was decreased and catalase enzyme activity in erythrocytes was increased after losartan treatment. Losartan reduced cortico-medullary necrosis and tubular dilatation in the kidney. High expression of pro-apoptotic Bax protein in the injured kidney was downregulated after losartan treatment. Our results reveal that angiotensin II (via AT1R) mediates the most postischemic injuries in hypertensive kidney through oxidative stress enhancement. Therefore, blockade of AT1R may have beneficial effects in hypertensive patients who have developed ARF. 相似文献
35.
A chitosan Schiff base with an aromatic aldehyde was synthesized and characterized by FTIR and NMR spectroscopies. Furthermore, the degree of substitution was calculated based on the ratios of the area of the proton of the imine (Aimine) and the area of the peak of the proton of the pyranose ring (AH-2). The antimicrobial activities were determined against bacterial and fungal strains, as well as multiple drug-resistant (MDR) bacteria. The chitosan Schiff base was also tagged with medicinal plants, for example, Curcuma longa, Peganum harmala, Lepidium sativam, and cruciferous vegetables, and the biological activities determined against pathogenic bacterial and fungal strains. The chitosan Schiff base showed maximum zone of inhibition of 22 mm against Staphylococcus aureus with a minimum zone of inhibition of 15 mm against Bacillus cereus. The chitosan Schiff base was fused with C longa, isothiocyanates and a combined mixture of P harmala and L sativam that has shown activities against Escherichia coli with a zone of inhibition of 28, 24, and 30 mm, respectively. The Schiff base of chitosan fused with medicinal plants also showed significant inhibitory activities against MDR bacteria. 相似文献
36.
Branko?Petrinec Marina?Poje?Sovilj Dinko?Babi? Tomislav?Me?trovi? Igor?Miklav?i? Vanja?Radoli? Denis?Stani? Branko?Vukovi? Marko??o?tari?Email authorView authors OrcID profile 《Radiation and environmental biophysics》2018,57(3):285-292
A study of the environmental radioactivity in the Kopa?ki Rit Nature Park, Croatia, is presented. This wildlife reserve is part of the Middle Danube River Basin, and it is exposed to various pollutants due to a number of human activities in the surroundings, where there is a nuclear power plant and also urban centres and areas of intense agricultural production. Results for the activity concentrations of soil and surface water samples do not indicate any elevated radioactivity level, which is confirmed by on-site measurements of ambient dose rate equivalent. An assessment of the radiological load on the local biota, carried out using the ERICA tool, implies an overall low radiological risk even if conservative values of the risk quotient are used. Therefore, human activities do not have a significant effect on the radiological load on the Kopa?ki Rit area. A similar conclusion might be made with regard to numerous similar environments in the Middle Danube River Basin. 相似文献
37.
Muhammad Afzal Salem Safer Alghamdi Muhammad Habib ur Rahman Awais Ahmad Tahir Farooq Mukhtar Alam Imtiaz Ali Khan Hidayat Ullah Wajid Nasim Shah Fahad 《Biotechnology letters》2018,40(3):479-492
As PCR methods have improved over the last 15 years, there has been an upsurge in the number of new DNA marker tools, which has allowed the generation of high-density molecular maps for all the key Brassica crop types. Biotechnology and molecular plant breeding have emerged as a significant tool for molecular understanding that led to a significant crop improvement in the Brassica napus species. Brassica napus possess a very complicated polyploidy-based genomics. The quantitative trait locus (QTL) is not sufficient to develop effective markers for trait introgression. In the coming years, the molecular marker techniques will be more effective to determine the whole genome impairing desired traits. Available genetic markers using the single-nucleotide sequence (SNP) technique and high-throughput sequencing are effective in determining the maps and genome polymorphisms amongst candidate genes and allele interactions. High-throughput sequencing and gene mapping techniques are involved in discovering new alleles and gene pairs, serving as a bridge between the gene map and genome evaluation. The decreasing cost for DNA sequencing will help in discovering full genome sequences with less resources and time. This review describes (1) the current use of integrated approaches, such as molecular marker technologies, to determine genome arrangements and interspecific outcomes combined with cost-effective genomes to increase the efficiency in prognostic breeding efforts. (2) It also focused on functional genomics, proteomics and field-based breeding practices to achieve insight into the genetics underlying both simple and complex traits in canola. 相似文献
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