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排序方式: 共有199条查询结果,搜索用时 31 毫秒
101.
This study was designed to investigate the possible effects of 24-Epibrassinolide (BR), arbuscular mycorrhizal (AM) fungus, Glomus mosseae, singularly and collectively under salt stress in wheat (Triticum aestivum L.) plants. After foliar spraying of mycorrhizal and non-mycorrhizal plants by 5 µM epibrassinolide (24-Epi), they were treated with 0 and 150 mM NaCl for 2 weeks and then harvested. The results showed interactions of G. mosseae and 24-Epi could alleviate the adverse effects of salinity by improving relative water content (RWC) of leaves (62%), relative growth rate (40.74%), shoot fresh weights (39.83%) and shoot phosphorous content (63.93%), stimulating leaf enzymatic antioxidant activities including catalase (2.24 fold) and ascorbate peroxidase (2.18 fold) as well as malondialdehyde (36.17%) and H2O2 concentrations (49.74%) as compared to those of NaCl treatments. Moreover, mycorrhizal dependency of root dry weight (2%) and phosphorus concentration (0.4%) increased with AM infection and 24-Epi application under saline condition. Leaf RWC, also, negatively correlated with membrane electrolyte leakage. Furthermore, the greatest mitigating effects were observed in mycorrhizal plants subjected to NaCl and 24-Epi. This study indicated that 24-Epi application and AM fungi may synergistically mitigate harmful impacts of salinity in wheat plants.  相似文献   
102.
This study was conducted to synchronize follicle wave emergence prior to superovulation using either GnRH or progestogen treatments, in Bactrian camels. GnRH group camels (n=5) received 20 microg of the GnRH analogue Buserelin on Days -18 and -4 of the experiment (initiation of superovulation=Day 0). Camels in the progestogen group (n=5) received two consecutive treatments of progestogens, 7 days apart, on Days -14 and -8 of the experiment. On each occasion, each female received three norgestomet implants and 200mg progesterone (i.m.) and all implants were removed 14 days after the first progestogen treatment coinciding with Day -1 of superovulation. A combination of eCG and FSH was used to induce superovulation and the growth of all subsequent follicles and CLs were monitored daily by ultrasonography. Following the first GnRH injection, mature follicles ovulated within 1-2 days, and a new follicle wave emerged after 3+/-0.77 days. At the time of the second GnRH injection, a mature follicle (15.6+/-0.97 mm) ovulated and a new follicular wave emerged between 1 and 2 days after GnRH injection. Growing follicles at the time of the first progestogen treatment became either atretic (n=1) or persistent (n=4) and a new follicle wave (n=3) emerged 3-6 days later. At the initiation of superovulation, the diameters of the largest follicle in GnRH and progestogen groups were 7.4+/-0.59 and 20.5+/-2.26 mm, respectively but after superovulation and mating there was no significant differences in the number of unovulated follicles or CLs between groups. In conclusion, two GnRH injections, 14 days apart, may be used to synchronize follicle wave emergence in Bactrian camel.  相似文献   
103.
Probiotics and Antimicrobial Proteins - We searched bibliographic databases from inception through May 2018 to evaluate the effect of probiotics (or synbiotics) supplementation in women suffering...  相似文献   
104.
Exploring various cyclization strategies, using a submicromolar pyrazole HTS screening hit 6 as a starting point, a novel indazole based CCR1 antagonist core was discovered. This report presents the design and SAR of CCR1 indazole and azaindazole antagonists leading to the identification of three development compounds, including 19e that was advanced to early clinical trials.  相似文献   
105.
This work describes the performance of cytochrome c/nickel oxide nanoparticles/glassy carbon electrode, prepared by the electrochemical deposition of the nickel oxide nanoparticles (NiO NPs) on the glassy carbon (GC) electrode surface and the cytochrome c immobilization on the nickel oxide nanoparticle surfaces. An extensive sample examination with the help of the SEM and AFM presented the existence of different geometrical shapes of the nickel oxide particles. These geometrical structures could lead to the better immobilization of proteins on their surfaces. The resulting electrode displayed an excellent behavior for the redox of the cytochrome c. Also, the resulting heme protein exhibited a direct electrical contact with the electrode because of the structural alignment of the heme protein on the nanometer-scale nickel oxide surfaces. This method could be suitable for applications to nanofabricated devices. In the end, it was concluded that the cytochrome c could be tethered to the nanometer-scale nickel oxide surfaces.  相似文献   
106.

Background

Chronic hepatitis C virus infection is a major cause of liver disease in Switzerland and carries a significant cost burden. Currently, only conservative strategies are in place to mitigate the burden of hepatitis C in Switzerland. This study expands on previously described modeling efforts to explore the impact of: no treatment, and treatment to reduce HCC and mortality. Furthermore, the costs associated with untreated HCV were modeled.

Methods

Hepatitis C disease progression and mortality were modeled. Baseline historical assumptions were collected from the literature and expert interviews and strategies were developed to show the impact of different levels of intervention (improved drug cure rates, treatment and diagnosis) until 2030.

Results

Under the historical standard of care, the number of advanced stage cases was projected to increase until 2030, at which point the annual economic burden of untreated viremic infections was projected to reach €96.8 (95% Uncertainty Interval: €36 – €232) million. Scenarios to reduce HCV liver-related mortality by 90% by 2030 required treatment of 4,190 ≥F2 or 3,200 ≥F3 patients annually by 2018 using antivirals with a 95% efficacy rate. Delaying the implementation of these scenarios by 2 or 5 years reduced the impact on mortality to 75% and 57%, respectively.

Conclusions

With today’s treatment efficacy and uptake rates, hepatitis C disease burden is expected to increase through 2030. A substantial reduction in disease burden can be achieved by means of both higher efficacy drugs and increased treatment uptake. However, these efforts cannot be undertaken without a simultaneous effort to diagnose more infections.  相似文献   
107.

Background  

Replication origins are considered important sites for understanding the molecular mechanisms involved in DNA replication. Many computational methods have been developed for predicting their locations in archaeal, bacterial and eukaryotic genomes. However, a prediction method designed for a particular kind of genomes might not work well for another. In this paper, we propose the AT excursion method, which is a score-based approach, to quantify local AT abundance in genomic sequences and use the identified high scoring segments for predicting replication origins. This method has the advantages of requiring no preset window size and having rigorous criteria to evaluate statistical significance of high scoring segments.  相似文献   
108.
SH Chung  TW Allen  M Hoyles    S Kuyucak 《Biophysical journal》1999,77(5):2517-2533
The physical mechanisms underlying the transport of ions across a model potassium channel are described. The shape of the model channel corresponds closely to that deduced from crystallography. From electrostatic calculations, we show that an ion permeating the channel, in the absence of any residual charges, encounters an insurmountable energy barrier arising from induced surface charges. Carbonyl groups along the selectivity filter, helix dipoles near the oval chamber, and mouth dipoles near the channel entrances together transform the energy barrier into a deep energy well. Two ions are attracted to this well, and their presence in the channel permits ions to diffuse across it under the influence of an electric field. Using Brownian dynamics simulations, we determine the magnitude of currents flowing across the channel under various conditions. The conductance increases with increasing dipole strength and reaches its maximum rapidly; a further increase in dipole strength causes a steady decrease in the channel conductance. The current also decreases systematically when the effective dielectric constant of the channel is lowered. The conductance with the optimal choice of dipoles reproduces the experimental value when the dielectric constant of the channel is assumed to be 60. The current-voltage relationship obtained with symmetrical solutions is linear when the applied potential is less than approximately 100 mV but deviates from Ohm's law at a higher applied potential. The reversal potentials obtained with asymmetrical solutions are in agreement with those predicted by the Nernst equation. The conductance exhibits the saturation property observed experimentally. We discuss the implications of these findings for the transport of ions across the potassium channels and membrane channels in general.  相似文献   
109.
110.
Human adult stem cells, which are capable of self‐renewal and differentiation into other cell types, can be isolated from various tissues. There are no ethical and rejection problems as in the case of embryonic stem cells, so they are a promising source for cell therapy. The human body contains a great amount of adipose tissue that contains high numbers of mesenchymal stem cells. Human adipose‐derived stem cells (hADSCs) could be easily induced to form neuron‐like cells, and because of its availability and abundance, we can use it for clinical cell therapy. On the other hand, T3 hormone as a known neurotropic factor has important impressions on the nervous system. The aim of this study was to explore the effects of T3 treatment on neural differentiation of hADSCs. ADSCs were harvested from human adipose tissue, after neurosphere formation, and during final differentiation, treatment with T3 was performed. Immunocytochemistry, real‐time RT‐PCR, Western blotting techniques were used for detection of nestin, MAP2, and GFAP markers in order to confirm the effects of T3 on neural differentiation of hADSCs. Our results showed an increase in the number of glial cells but reduction in neuronal cells number fallowing T3 treatment. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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