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171.

A viable option for increasing nitrogen (N) use efficiency and mitigation of negative impacts of N on the environment is to capitalize on multi-element interactions through implementation of nutrient management programs that provide balanced nutrition. Numerous studies have demonstrated the immediate efficacy of this approach in the developing regions like China and India as well as developed countries in North America. Based on 241 site-years of experiments in these countries, the first-year N recovery efficiency (RE) for the conventional or check treatments averaged 21% while the balanced treatments averaged 54% RE, for an average increase of 33% in RE due to balanced nutrition. Effective policies to promote adoption are most likely those that enable site-specific approaches to nutrient management decisions rather than sweeping, nation-wide incentives supporting one nutrient over another. Local farmers, advisers and officials need to be empowered with tools and information to help them define necessary changes in practices to create more balanced nutrient management.

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172.
173.
The mTOR (mammalian or mechanistic Target of Rapamycin) is linked with oral cancer. Therefore, it is of interest to study the molecular docking-based binding of paclitaxel (a FDA approved drug for oral cancer) and its analogues with mTOR. Hence, we report the binding features of 10-Deacetyltaxol, 7-Epi-10-deacetyltaxol, 7-Epi-Taxol and 6alpha-Hydroxypaclitaxel with mTOR for further consideration.  相似文献   
174.
The aim of this study was to evaluate the effect of putrescine on ovarian activity and the rate of embryonic development in Cynopterus sphinx during delayed development. The result showed the presence of a rate‐limiting enzyme, ornithine decarboxylase‐1, in both ovary and utero‐embryonic unit of C. sphinx suggests a synthesis of putrescine in these sites. The corpus luteum showed increased, whereas utero‐embryonic unit showed decreased production of putrescine during delayed development as compared with the normal development. The bat treated in vivo with putrescine during delayed development showed increase in progesterone and estradiol synthesis, correlated with increased expression of luteinizing hormone receptor, steroidogenic acute receptor protein, and 3β‐hydroxysteroid dehydrogenase through extracellular signal‐regulated kinase (ERK1/2)‐mediated pathway in the ovary; but showed increase in the weight and expression of progesterone receptor (PR), B‐cell lymphoma 2, proliferating cell nucleus antigen, and vascular endothelial growth factor proteins in utero‐embryonic unit. The in vitro treatment of putrescine showed stimulatory whereas treatment with an inhibitor of putrescine, 2‐difluoromethylornithine caused an inhibitory effect on ovarian progesterone synthesis and cell proliferation, and cell survival in the utero‐embryonic unit. In conclusion, the putrescine showed two separate roles during embryonic diapause, high concentration of putrescine in the ovary may support corpus luteum and basal synthesis of progesterone, whereas a low level of putrescine causes retarded embryonic development by inhibiting cell proliferation in the utero‐embryonic unit. The bat treated with putrescine either directly promotes cell proliferation, cell survival, and angiogenic activities or acts indirectly increasing PR on utero‐embryonic unit thereby activating development in delayed embryo in C. sphinx.  相似文献   
175.
Protease inhibitors are well known to have several applications in medicine and biotechnology. Several plant sources are known to return potential protease inhibitors. In this study plants belonging to different families of Leguminosae, Malvaceae, Rutaceae, Graminae and Moringaceae were screened for the protease inhibitor. Among them Moringa oleifera, belonging to the family Moringaceae, recorded high level of protease inhibitor activity after ammonium sulfate fractionation. M. oleifera, which grows throughout most of the tropics and having several industrial and medicinal uses, was selected as a source of protease inhibitor since so far no reports were made on isolation of the protease inhibitor. Among the different parts of M. oleifera tested, the crude extract isolated from the mature leaves and seeds showed the highest level of inhibition against trypsin. Among the various extraction media evaluated, the crude extract prepared in phosphate buffer showed maximum recovery of the protease inhibitor. The protease inhibitor recorded high inhibitory activity toward the serine proteases thrombin, elastase, chymotrypsin and the cysteine proteases cathepsin B and papain which have more importance in pharmaceutical industry. The protease inhibitor also showed complete inhibition of activities of the commercially available proteases of Bacillus licheniformis and Aspergillus oryzae. However, inhibitory activities toward subtilisin, esperase, pronase E and proteinase K were negligible. Further, it was found that the protease inhibitor could prevent proteolysis in a commercially valuable shrimp Penaeus monodon during storage indicating the scope for its application as a seafood preservative. This is the first report on isolation of a protease inhibitor from M. oleifera.  相似文献   
176.
Cloning and sequencing of beta toxin gene of Clostridium perfringens type C   总被引:1,自引:0,他引:1  
A gene encoding beta toxin was amplified by polymerase chain reaction from C. perfringens type C isolate and cloned in pUC 19 vector. The nucleotide sequence was identical with C. perfringens type B beta toxin gene sequence. The Southern hybridization using labelled beta toxin gene probe revealed the presence of positive signals only in beta producing C. perfingens.  相似文献   
177.
Russian Journal of Bioorganic Chemistry - 1,4-Dihydropyridinecarboxylates were prepared by the reaction of nicotinaldehydes with aminocrotonoates in the presence of p-TsOH at room temperature. The...  相似文献   
178.
Himalayan alder species are proven to be very useful in traditional as well as contemporary agroforestry practice. These nitrogen-fixing trees are also useful in the land restoration. Therefore, understanding the distribution of Himalayan alder and the potential zone for plantation is meaningful in the agroforestry sector. Suitable climatic zones of Alnus spp. were modelled in MaxEnt software using a subset of least correlated bioclimatic variables for current conditions (1950-2000), topographic variables (DEM derived) and Landuse Landcover (LULC) data. We generated several models and selected the best model against random models using ANOVA and t-test. The environmental variables that best explained the current distribution of the species were identified and used to project into the future. For future projections, ensemble scenarios of climate change projection derived from the results of 19 Earth System Models (ESM) were used. Our model revealed that the most favorable conditions for Alnus nepalensis are in central Nepal in the moist north-west facing slope, whereas for Alnus nitida they are in western Nepal. The major climatic factor that contributes to Alnus species distribution in Nepal appears to be precipitation during the warmest quarter for A. nepalensis and precipitation during the driest quarter for A. nitida. Future projections revealed changes in the probability distribution of these species, as well as where they need conservation and where they can be planted. Also, our model predicts that the distribution of Alnus spp. in hilly regions will remain unchanged, and therefore may represent sites that can be used to revitalize traditional agroforestry systems and extract source material for land restoration.  相似文献   
179.
Sepsis is an exaggerated systemic inflammatory response to persistent bacteria infection with high morbidity and mortality rate clinically. β-arrestin 2 modulates cell survival and cell death in different systems. However, the effect of β-arrestin 2 on sepsis-induced cardiac dysfunction is not yet known. Here, we show that β-arrestin 2 overexpression significantly enhances animal survival following cecal ligation and puncture (CLP)-induced sepsis. Importantly, overexpression of β-arrestin 2 in mice prevents CLP-induced cardiac dysfunction. Also, β-arrestin 2 overexpression dramatically attenuates CLP-induced myocardial gp130 and p38 mitogen-activated protein kinase (MAPK) phosphorylation levels following CLP. Therefore, β-arrestin 2 prevents CLP-induced cardiac dysfunction through gp130 and p38. These results suggest that modulation of β-arrestin 2 might provide a novel therapeutic approach to prevent cardiac dysfunction in patients with sepsis.  相似文献   
180.
Ignisphaera aggregans Niederberger et al. 2006 is the type and sole species of genus Ignisphaera. This archaeal species is characterized by a coccoid-shape and is strictly anaerobic, moderately acidophilic, heterotrophic hyperthermophilic and fermentative. The type strain AQ1.S1(T) was isolated from a near neutral, boiling spring in Kuirau Park, Rotorua, New Zealand. This is the first completed genome sequence of the genus Ignisphaera and the fifth genome (fourth type strain) sequence in the family Desulfurococcaceae. The 1,875,953 bp long genome with its 2,009 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
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