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81.
Overuse of the chemical compounds and toxic elements leads to problems and transmission of contaminants and pollutants to humans and other living organisms. One of the agricultural industries' byproducts is production of various composts from the organic raw materials and its best type is Vermicompost. In this study, effects of raw materials on qualitative and quantitative characteristics of vermicompost are discussed. To do so, sheep manure, pomegranate peels, spent mushroom compost either singly or double-, triple-, or four-fold chopped corn, sugar beet pulp, and sawdust were used. This research project was conducted in a completely randomized design experiment with 23 treatments with 3 replications. Results revealed that various bed combinations exert different effects on vermicompost quality such that the vermicomposting process led to a significant decrease in electrical conductivity and a significant increase in pH in most of the culture (seed) beds. Also, the levels of nitrogen, phosphorous, and potassium in most treatments increased following completion of the vermicomposting process. As a result, this process can be introduced as an organic fertilizer with complete nutrients for improving chemical characteristics of agricultural wastes to usable fertilizers.  相似文献   
82.
Background:Lithium is a therapeutic option for the treatment of the acute phase of the bipolar disorder and long-term management of this disorder. However, it is estimated that 10 to 60% of patients do not properly response to this medication.Methods:To investigate the role of MARK2 gene in response to lithium, we genotyped the MARK2 rs10792421 polymorphism in Iranian bipolar patients using ARMS-PCR.Results:Results of this study showed a significant association of this polymorphism with response to lithium. The A allele was more frequent in the responder than the non-responder group and also in the semi- responder group compared to the non-responder group in the codominant model of analysis. AA and AG genotypes were more frequent in both the responder and semi-responder groups compared to the non-responder group in dominant model of analysis.Conclusion:Based on the findings of the current study, the rs10792421 variant of MARK2 gene could be considered as a potential biomarker for predicting the treatment outcome of bipolar disorder type 1 in Iranian population. Key Words: Biomarkers, Bipolar, Lithium, Genotyping  相似文献   
83.
Oak decline syndrome is characterized by periodic occurrences of decline and death of oaks over widespread areas. An outbreak of a new emerging disease on oak trees was reported in the Hyrcanian forest of Iran (Mazandaran and Golestan provinces) that showed stem bleeding and canker symptoms. Bacterial isolates were characterized through biochemical and physiological tests, protein electrophoresis, DNA fingerprinting (rep‐PCR, ERIC and BOX primers) and sequencing of 16S rRNA and MLSA (multilocus sequencing analysis) for housekeeping genes (gyrB, infB and atpD). A complex community of the genus Brenneria spp. (Brenneria goodwinii, Brenneria roseae subsp. roseae, Brenneria sp. and Brenneria nigrifluens) and a few isolates in the genus Gibbsiella were identified as major groups involved. Isolate differentiation was more accurate using concatenated partial gene sequences within the main groups. All bacterial isolates showed hypersensitivity reactions (HR) on Pelargonium leaves (Pelargonium × hortorum). Pathogenicity studies of different Brenneria and Gibbsiella strains revealed that they have potential to cause the disease in oak seedlings and devastating oak canker and stem bleeding symptoms in northern Iran. Due to the presence of several potentially pathogenic agent(s) associated with the oak decline, identification of the principal agent(s) is of major interest. To our knowledge, this is the first report of potentially pathogenic bacteria associated with oak bleeding and canker in Iran.  相似文献   
84.
85.
Abstract: Nonhuman primates (NHPs) are commonly used for biomedical research because of the high level of gene homology that underlies physiologic similarity to human beings. Malaria parasites of the genus Plasmodium cause one of the most frequent parasitic diseases of NHPs originating from tropical and subtropical areas and as such represent a significant research confounder. Malaria in NHPs presents a diagnostic challenge especially to those laboratories that see no more than a few malaria cases per year in NHPs. The accurate and timely diagnosis of malaria infection in NHPs facilitates the appropriate treatment of individuals infected with the malaria parasites. Conventional microscopy based on the examination of Giemsa‐stained thick and thin blood films remains the mainstay of laboratory diagnosis of malaria infection because of the high diagnostic sensitivity and specificity and also the capability for Plasmodium species identification and parasite counts. This procedure is recognized as technically difficult and time‐consuming, requiring considerable training to obtain the necessary skills. In the past few years, efforts to replace the traditional but tedious reading of blood films have led to different techniques for the detection of malaria parasites, including fluorescence microscopy, detection of intraleukocytic hemozoin or malaria pigment using automated blood cell analyzers, immunochromatographic rapid diagnostic tests based on malaria antigen detection, and PCR assays. These techniques offer new approaches for diagnosing malaria in NHPs. This review focuses on the available laboratory diagnostic tools for malaria in NHPs.  相似文献   
86.
The objective of this study was to determine the effect of the presence of recombinant ovine growth hormone either alone or together with follicle stimulating hormone (FSH) during ovine oocyte in vitro maturation (IVM) on nuclear maturation and subsequent embryo development. Moreover, the effect of growth hormine (GH) on embryo development whether influenced by the presence of foetal bovine serum (FBS) was assessed. The abattoir‐derived oocytes were randomly divided into four treatment groups and cultured in maturation medium supplemented with: (i) 0.05 IU/ml FSH; (ii) 300 ng/ml roGH; (iii) FSH + roGH; and (iv) no FSH and GH (control). The percentages of germinal vesicle‐stage oocytes in GH‐treated group after 8 h of culture was significantly higher than the FSH and FSH + GH groups and lower than control (22.4%, 8.7%, 9.1%, and 32% respectively). The percentage of MII‐stage oocytes was significantly increased in the presence of GH after 16 and 24 h of culture compared to the control (44.7% and 83.1% vs 32.6% and 73.6% respectively). There was no significant synergism between GH and FSH in terms of nuclear maturation. The blastocyst rates in serum‐supplemented groups were enhanced by the presence of FSH and GH compared to the control (35.4% and 31.3 vs 11.4% respectively). Compared with either GH or FSH alone, the subsequent embryo development (blastocyst rate), however, was negatively influenced by co‐presence of both hormones (22.8%). In contrast, the corresponding values were not affected in the absence of serum. In conclusion, GH had positive effect on nuclear maturation of sheep oocytes. Moreover, the pattern of the effect of GH on embryo development was influenced by the presence of FBS during IVM.  相似文献   
87.

Background

The aim of this study was to fabricate the poly caprolactone (PCL) aligned nanofiber scaffold and to evaluate the survival, adhesion, proliferation, and differentiation of rat hair follicle stem cells (HFSC) in the graft material using electrospun PCL nanofiber scaffold for tissue engineering applications.

Methods

The bulge region of rat whisker was isolated and cultured in DMEM: nutrient mixture F-12 supplemented with epidermal growth factor. The morphological and biological features of cultured bulge cells were observed by light microscopy using immunocytochemistry methods. Electrospinning was used for production of PCL nanofiber scaffolds. Scanning electron microscopy (SEM), 3-(4, 5-di-methylthiazol- 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, and histology analysis were used to investigate the cell morphology, viability, attachment and infiltration of the HFSC on the PCL nanofiber scaffolds.

Results

The results of the MTT assay showed cell viability and cell proliferation of the HFSC on PCL nanofiber scaffolds. SEM microscopy images indicated that HFSC are attached, proliferated and spread on PCL nanofiber scaffolds. Also, immunocytochemical analysis showed cell infiltration and cell differentiation on the scaffolds.

Conclusion

The results of this study reveal that PCL nanofiber scaffolds are suitable for cell culture, proliferation, differentiation and attachment. Furthermore, HFSC are attached and proliferated on PCL nanofiber scaffolds.Key Words: Nanofiber, Electrospinning, Stem cells, Tissue engineering  相似文献   
88.
To provide insight into the genetic structure of Mycosphaerella graminicola populations in Iran, a total of 221 isolates were collected from naturally infected wheat fields of five major wheat‐growing provinces and analysed using AFLP markers and mating‐type loci. All populations showed intermediate to high genotypic diversity. In the Golestan and Ardabil populations two mating types were found at near‐equal frequencies, whilst all populations were in gametic disequilibrium. Moreover, clonal haplotypes were identified in different sampling sites within a field in both the Khuzestan and Fars provinces, demonstrating that pycnidia are probably the primary source of inoculum. All five populations had low levels of gene diversity and had private bands. Low levels of gene flow and high genetic differentiation were observed among populations and different clustering methods revealed five genetically distinct groups in accordance with the sampling areas. The Golestan and East Azarbaijan populations were more genetically differentiated than the others. Random genetic drift, selection and geographic barriers may account for the differentiation of the populations. The results of this study indicate a population structure of M. graminicola in Iran contrasting to that of most other countries studied.  相似文献   
89.
ABSTRACT

Evaluation of the relationship between soil properties and saffron yield estimation may contribute to agricultural planning in finding suitable lands for the growth of this valuable product. This study aimed to investigate the performance of artificial neural network (ANN), multiple linear regression (MLR), and adaptive neuro-fuzzy inference system (ANFIS) in terms of saffron yield estimation in some lands of Golestan province, Iran. To this end, 100 areas under saffron cultivation were selected. For rapid and low-cost saffron yield estimation, six different models were designed based on soil properties as inputs using MLR, ANN, and ANFIS methods. According to the results, ANN showed the highest accuracy (R2 = 0.58–0.89) in estimating saffron yield as compared to MLR (R2 = 0.41–0.47) and ANFIS (R2 = 0.41–0.69) models. A comparison of the results obtained from the six models defined in these three methods indicated that Model 4 (R2 Reg = 0.45, R2 ANFIS = 0.57, R2 ANN = 0.87), with the inputs, organic phosphorus, potassium, and calcium carbonate, was the best model in terms of accuracy and speed in estimating saffron yield phosphorus. The RI indexes for ANN in the model were 50% and 34% relative to MLR and ANFIS, respectively, demonstrating the higher accuracy of ANN in saffron yield estimation. The study results can be used to identify lands suitable for saffron cultivation in the study area using organic phosphorus and organic matter levels in the soil.  相似文献   
90.
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