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81.
82.
Effects of Short-Term Over-supplementation of Copper in Milk on Hematology,Serum Proteins,Weight Gain,and Health in Dairy Calves 总被引:1,自引:0,他引:1
Zahra Naseri Mehrdad Mohri Mohammad R. Aslani Ali A. Alavi Tabatabaee 《Biological trace element research》2011,139(1):24-31
Thirty-six calves were used in the present study. The animals were divided equally into three groups (control, test 1, and
test 2). The three groups of calves were homogeneous for parity of dams, sex, and month of birth. From 14 days of age, in
the test 1 group copper as copper sulfate (Merck Co, Germany) was added to each meal of milk at a rate of 10 mg/kg of milk
for 14 days and in test 2 group copper as copper sulfate was added to each meal of milk at a rate of 20 mg/kg of milk for
14 days. Blood samples were taken by jugular venipuncture using disposable syringes at 14 (before Cu supplementation), 30,
60, and 80 days of age. Anticoagulated blood was used for CBC determination. Plane tubes were used for harvesting of serum
and the amounts of total serum protein, albumin, iron, and copper were measured. Calves were weighted at birth and at the
end of trial (day 80) and total gain and mean daily gain were calculated. Days of treatment for ill calves were also recorded
during experiment. Group (treatment) had no significant effect on the amounts of measured parameters except MCH values (p < 0.05) which were significantly lower in test 1 group than other trial groups. Age (sampling time) had significant effects
on the values of most measured parameters (p < 0.05) except WBC, lymphocyte, total protein, and fibrinogen. Significant interactions between sampling time and group were
not seen for any of measured parameters. No significant differences were seen for total weight gain and mean daily gain between
trial groups. Chi-square test revealed no significant difference for the days of treatment between trials groups. 相似文献
83.
The purpose of this review is to present the most common and emerging DNA‐based methods used to generate data for biodiversity and biomonitoring studies. As environmental assessment and monitoring programmes may require biodiversity information at multiple levels, we pay particular attention to the DNA metabarcoding method and discuss a number of bioinformatic tools and considerations for producing DNA‐based indicators using operational taxonomic units (OTUs), taxa at a variety of ranks and community composition. By developing the capacity to harness the advantages provided by the newest technologies, investigators can “scale up” by increasing the number of samples and replicates processed, the frequency of sampling over time and space, and even the depth of sampling such as by sequencing more reads per sample or more markers per sample. The ability to scale up is made possible by the reduced hands‐on time and cost per sample provided by the newest kits, platforms and software tools. Results gleaned from broad‐scale monitoring will provide opportunities to address key scientific questions linked to biodiversity and its dynamics across time and space as well as being more relevant for policymakers, enabling science‐based decision‐making, and provide a greater socio‐economic impact. As genomic approaches are continually evolving, we provide this guide to methods used in biodiversity genomics. 相似文献
84.
Shiva Torabian Mehrdad Ranaei Saeid Pourmanafi Laurie Chisholm 《Contemporary Problems of Ecology》2018,11(6):687-696
Species distribution in space is important in habitat conservation and biodiversity protection, so gaining knowledge about species range would be worthwhile to rescue endangered species and plan conservation policy. This study evaluates and compares the performance of an array of Species Distribution Models (SDMs), namely RF, SVM, MaxEnt, GLMNET, and MARS, in predicting rare sand cat distribution across a large unprotected sand dune area in central Iran. Due to absence of reliable data and difficulties in recording the species itself, the SDMs were challenged by limited data including 55 absence (background) and 40 presence points as well as nine climatic and geological parameters that influence on species distribution, including humidity, maximum, minimum and mean temperature, precipitation, amount of sunshine, ground water level, aspect, and DEM. Moreover, each model was replicated 20 times and the statistics including TSS, AUC, COR and Deviance were computed. Then, based on computed statistics, the model performances were evaluated by TUKEY and ANOVA. Finally, ensemble map was obtained by weighted approach using AUC. The results of this study showed that complex machine learning methods, like SVM, RF, and MaxEnt are more outperformed to predict the distribution of rare species. 相似文献
85.
Jiachuan Chen Jiran Dong Guihua Yang Ming He Feng Xu Pedram Fatehi 《Biotechnology for biofuels》2018,11(1):337
Background
In the kraft-based dissolving pulp production process, pre-hydrolysis liquor (PHL) is produced, which contains hemicelluloses, lignin, furfural and acetic acid. PHL is currently burned in the recovery boiler of the kraft pulping process, but it can be utilized for the generation of high-valued products, such as xylitol and xylanase, via fermentation processes. However, some PHL constituents, e.g., furfural and lignin, are contaminants for fermentation processes and they must be eliminated for production of value-added products.Results
In this work, a process is introduced for removing contaminants of PHL. Ca(OH)2 treatment is the first step of this process, which removed 41.2% of lignin and negligible amount of sugars. In this step, a notable increase in the concentration of acetic acid was achieved (ranging from 6.2 to 11.7 g/L). In the second step, the implementation of adsorption using activated carbon (AC) at 1 wt% dosage led to additional 32% lignin and 5.9% xylosugar removals. In addition, laccase assisted activated carbon treatment led to further removal of lignin via accelerating lignin polymerization and adsorption on AC (i.e., removal from PHL). Overall, 90.7% of lignin, 100% of furfural, 5.7% of xylose, and 12% of xylan were removed from PHL, while the concentration of acetic acid became twofolds in the PHL.Conclusions
This study reports an attractive process for purifying sugars and acetic acid of PHL. This process may be implemented for producing sugar-based value-added products from PHL. It also discusses the mechanism of Ca(OH)2 treatment, AC adsorption and laccase assisted activated carbon treatment for lignin removal.86.
Mojtaba Alimolaei Mehdi Golchin Jalil Abshenas Majid Ezatkhah Mehrdad Shamsaddini Bafti 《Probiotics and antimicrobial proteins》2018,10(2):251-257
The alpha-toxin is one of the virulence factors of Clostridium perfringens for gas gangrene in humans and animals or necrotic enteritis in poultry. The C-terminal domain of this toxin ( cpa 247-370 ) was synthesized and cloned into pT1NX vector to construct the pT1NX-alpha plasmid. This surface-expressing plasmid was electroporated into Lactobacillus casei ATCC 393, generating the recombinant L. casei strain expressing alpha-toxoid (LC-α strain). Expression of this modified alpha-toxoid was confirmed by SDS-PAGE, immunoblotting, and direct immunofluorescence microscopy. BALB/c mice, immunized orally by the recombinant LC-α strain, elicited mucosal and significantly humoral immune responses (p < 0.05) and developed a protection against 900 MLD/mL of the standard alpha-toxin. This study showed that this recombinant LC-α strain could be a promising vaccine candidate against gas gangrene and necrotic enteritis. 相似文献
87.
Daniel Hoffmann Mehrdad Ebrahimi Doreen Gerlach Peter Czermak 《Critical reviews in biotechnology》2018,38(5):729-744
The production of recombinant proteins in the microbial host Escherichia coli often results in the formation of cytoplasmic protein inclusion bodies (IBs). Proteins forming IBs are often branded as difficult-to-express, neglecting that IBs can be an opportunity for their production. IBs are resistant to proteolytic degradation and contain up to 90% pure recombinant protein, which does not interfere with the host metabolism. This is especially advantageous for host-toxic proteins like antimicrobial peptides (AMPs). IBs can be easily isolated by cell disruption followed by filtration and/or centrifugation, but conventional techniques for the recovery of soluble proteins from IBs are laborious. New approaches therefore simplify protein recovery by optimizing the production process conditions, and often include mild resolubilization methods that either increase the yield after refolding or avoid the necessity of refolding all together. For the AMP production, the IB-based approach is ideal, because these peptides often have simple structures and are easy to refold. The intentional IB production of almost every protein can be achieved by fusing recombinant proteins to pull-down tags. This review discusses the techniques available for IB-based protein production before considering technical approaches for the isolation of IBs from E. coli lysates followed by efficient protein resolubilization which ideally omits further refolding. The techniques are evaluated in terms of their suitability for the process-scale production and downstream processing of recombinant proteins and are discussed for AMP production as an example. 相似文献
88.
89.
90.
The aim of this work was to develop a procedure for encapsulation of diltiazem HCl by spray coagulation. Factors affecting
the formulations such as the effect of NaCl on the solubility of diltiazem in alginate solution, surface tension, pH, viscosity
of the coagulation medium, and the effect of drug load on drug release were studied. The drug load was increased substantially
from 10 up to 320 mg/mL by adding 1.2% w/v NaCl in 1% w/v alginate solution. More stable microcapsules were obtained at pH 4.6 (acetate buffer) than at a pH 2.8 (lactic acid), and
the microencapsulation process was favored by the type of chitosan that produced low turbidity and viscosity in the coagulation
medium. A dose of 50 mg/mL of diltiazem HCl, 1.2% w/v NaCl, and chitosan CS allowed higher amount of drug to be encapsulated. The high water solubility of diltiazem HCl leads
to fast release from the microcapsules. 相似文献