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131.
132.
An 8-week study was conducted to evaluate three different diets supplemented with bovine lactoferrin (LF) at 0 (control), 800, and 1200 mg LF kg?1 diet on somatic growth, hemato-immunological parameters, antioxidant status, and digestive enzyme activities in silvery-black porgy (Sparidentex hasta) juveniles. Fish fed the 800 mg LF kg?1 diet had higher growth performance and feed utilization parameters than the other groups. Hematological and liver antioxidant parameters were not affected by dietary LF supplementation. Fish fed the 800 mg LF kg?1 diet had higher plasma lysozyme activity values than the other groups. Total protease activity was higher in fish fed LF-supplemented diets than the control group. Results indicated that diet supplemented with 800 mg kg?1 for 8 weeks enhanced somatic growth performance, lysozyme activity, and proteolytic digestive enzyme activities in S. hasta, as well as improving feed efficiency parameters like the protein efficiency and feed conversion ratios.  相似文献   
133.
Origanum vulgare L is commonly known as a wild marjoram and winter sweet which has been used in the traditional medicine due to its therapeutic effects as stimulant, anticancer, antioxidant, antibacterial, anti-inflammatory and many other diseases. A reliable gene transfer system via Agrobacterium rhizogenes and plant regeneration via hairy roots was established in O. vulgare for the first time. The frequency of induced hairy roots was different by modification of the co-cultivation medium elements after infection by Agrobacterium rhizogenes strains K599 and ATCC15834. High transformation frequency (91.3 %) was achieved by co-cultivation of explants with A. rhizogenes on modified (MS) medium. The frequency of calli induction with an 81.5 % was achieved from hairy roots on MS medium with 0.25 mg/L?1 2,4-D. For shoot induction, initiated calli was transferred into a medium containing various concentrations of BA (0.1, 0.25, 0.5, 0.75 and 1 mg/L?1). The frequency of shoot generation (85.18 %) was achieved in medium fortified with 0.25 mg/L?1 of BA. Shoots were placed on MS medium with 0.25 mg/l IBA for root induction. Roots appeared and induction rate was achieved after 15 days.  相似文献   
134.
135.
In this research, biostratigraphy, microfacies analysis and sequence stratigraphic framework of the Asmari Formation are discussed at Sepidar Anticline, Interior Fars sub-Basin. The strata are Rupelian to Chattian in age. According to the distribution of benthic foraminifera, two assemblage zones were recognised (I-) Nummulites vascus–Nummulites fichteli and (II-) Archaias asmaricus/hensoni–Miogypsinoides complanatus. Eight microfacies types which can be grouped into three depositional environments are recognised. Distribution of Oligocene foraminifera together with other constituents allowed the identification of three third-order sequences at Asmari Formation. Correlation of analysed sections through Interior Fars sub-Basin represents the development of a carbonate ramp with a deepening trend from SE to NW along the Rupelian/Chattian boundary.  相似文献   
136.
Although the female gametophyte in angiosperms consists of just seven cells, it has a complex biological network. In this study, female gametophyte microarray data from Arabidopsis thaliana were integrated into the Arabidopsis interactome database to generate a putative interaction map of the female gametophyte development including proteome map based on biological processes and molecular functions of proteins. Biological and functional groups as well as topological characteristics of the network were investigated by analyzing phytohormones, plant defense, cell death, transporters, regulatory factors, and hydrolases. This approach led to the prediction of critical members and bottlenecks of the network. Seventy-four and 24 upregulated genes as well as 171 and 3 downregulated genes were identified in subtracted networks based on biological processes and molecular function respectively, including novel genes such as the pathogenesis-related protein 4, ER type Ca2+ ATPase 3, dihydroflavonol reductase, and ATP disulfate isomerase. Biologically important relationships between genes, critical nodes, and new essential proteins such as AT1G26830, AT5G20850, CYP74A, AT1G42396, PR4 and MEA were found in the interactome''s network. The positions of novel genes, both upregulated and downregulated, and their relationships with biological pathways, in particular phytohormones, were highlighted in this study.  相似文献   
137.
Establishing optimized protocols for micropropagation of some economical plants, such as Prunus sp., is still one of the most important challenges for in vitro plant culture researchers. As an example, micropropagation of GF677 hybrid rootstocks (peach × almond) are extremely dependent on the medium ingredients and a large undesirable proportion of GF677 shoots need to be discarded as a result of hyperhydricity and chlorosis. In this study, an artificial intelligence technique—specifically neurofuzzy logic—has been employed, as a modeling tool, to increase knowledge on the effect of 8 ion macronutrients (NH4 +, NO3 ?, Ca2+, K+, Mg2+, SO4 2?, PO4 2? and Na+; as inputs) on three growth parameters (outputs): total number of shoots per explant, healthy number of shoots per explant, and their bud number. The model delivered new insights, by three sets of IF–THEN rules, pinpointing the key role of NO3 ? and their interactions (NO3 ? × Ca2+ and NO3 ? × Ca2+ × K+) on all growth parameters measured. All growth parameters showed a high correlation ratio between experimental and predicted values being 77.48, 91.78 and 90.78 for total shoots, healthy number and bud number, respectively. Regression coefficients higher than 77 % together with statistical significant ANOVA (p < 0.01) indicated good performance of neurofuzzy logic models. Moreover, The model also can be used for inferring the best combination of ion concentrations to obtain high quality GF677 micropropagated shoots. In conclusion, we assess the utility of neurofuzzy logic technology in modeling complex databases, identifying new complex interactions among macronutrients, and inferring new results and valuable knowledge, which can be applied to design new plant tissue culture media and improve plant micropropagation.  相似文献   
138.
Due to the limitations in the clinical application of embryonic stem cells (ESC) and induced pluripotent stem cells, mesenchymal stem cells (MSCs) are now much more interesting for cell-based therapy. Although MSCs have several advantages, they are not capable of differentiating to all three embryonic layers (three germ layers) without cultivation under specific induction media. Hence, improvement of MSCs for cell therapy purposes is under intensive study now. In this study, we isolated MSCs from umbilical cord tissue at the single-cell level, by treatment with trypsin, followed by cultivation under suspension conditions to form a colony. These colonies were trypsin resistant, capable of self-renewal differentiation to the three germ layers without any induction, and they were somewhat similar to ESC colonies. The cells were able to grow in both adherent and suspension culture conditions, expressed both the MSCs markers, especially CD105, and the multipotency markers, i.e., SSEA-3, and had a limited lifespan. The cells were expanded under simple culture conditions at the single-cell level and were homogenous. Further and complementary studies are required to understand how trypsin-tolerant mesenchymal stem cells are established. However, our study suggested non-embryonic resources for future cell-based therapy.  相似文献   
139.
A halophilic archaeon, Halorubrum sp. strain Ha25, produced extracellular halophilic organic solvent-tolerant amylopullulanase. The maximum enzyme production was at high salt concentration, 3–4 M NaCl. Optimum pH and temperature for enzyme production were 7.0 and 40 °C, respectively. Molecular mass of purified enzyme was estimated to be about 140 kDa by SDS–PAGE. This enzyme was active on pullulan and starch as substrates. The apparent K m for the enzyme activity on pullulan was 4 mg/ml and for soluble starch was 1.8 mg/ml. Optimum temperature for amylolytic and pullulytic activities was 50 °C. Optimum pH for amylolytic activity was 7 and for pullulytic activity was 7.5. This enzyme was active over a wide range of concentrations (0–4.5 M) of NaCl. The effect of organic solvents on the enzyme activities showed that this enzyme was more stable in the presence of non-polar organic solvents than polar solvents. This study is the first report on amylopullulanase production in halophilic bacteria and archaea.  相似文献   
140.
Pseudomonas aeruginosa as an opportunistic pathogen causes lethal infections in immunocompromised individuals. This bacterium possesses a polar flagellum made up of flagellin subunits. Flagella have important roles in motility, chemotaxis, and establishment of P. aeruginosa in acute phase of infections. Isolation, cloning, and expression of flagellin were aimed at in this study. Flagellin gene (fliC) of P. aeruginosa strain 8821M was isolated by PCR and cloned into a pET expression vector. The recombinant flagellin (46 kDa) was overexpressed as inclusion bodies (IBs). IBs were solubilized in guanidine hydrochloride (GuHCl) followed by affinity-purification and renatured using Ni2+-Sepharose resin. Recombinant flagellins reacted with the serum from a rabbit previously immunized with native flagellin. In addition, polyclonal antiserum raised against the recombinant flagellin was shown to significantly inhibit the cell motility of P. aeruginosa strain 8821M in vitro.  相似文献   
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