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841.
The breeding success of the Grey Hypocolius Hypocolius ampelinus is mainly determined by local grasshopper density.  相似文献   
842.
843.
Two trials were conducted in a 2?×?2?+?1 factorial arrangement based on a completely randomized design to evaluate the effects of different sources of selenium (Se) on performance, blood metabolites, and nutrient digestibility in male lambs on a barley-based diet. The first trial lasted for 70 days and consisted of 30 lambs (35.6?±?2.6 kg mean body weight, about 4–5 months of age) which were randomly allotted to five treatments including: (1) basal diet (containing 0.06 mg Se/kg DM; control) without supplementary Se, (2) basal diet?+?0.20 mg/kg Se as sodium selenite (SeS 0.20), (3) basal diet?+?0.40 mg/kg Se as sodium selenite (SeS 0.40), (4) basal diet?+?0.20 mg/kg Se as selenium yeast (SeY 0.20), and (5) basal diet?+?0.40 mg/kg Se as selenium yeast (SeY 0.40). For the second trial, four lambs from each group of experiment 1 were randomly allocated to individual metabolic cages for 14 days to measure the effects of dietary Se on nutrient digestibility. The results revealed that there were no significant differences for average daily gain, average daily feed intake, feed/gain ratio, hematological parameters (packed cell volume, red blood cell, white blood cell, and hemoglobin values), serum total protein, albumin, globulin, aspartate amino transferase, alkaline phosphatase, and creatine phosphokinase due to supplementation of different amounts and sources of Se in lambs. Dietary Se supplementation significantly improved (P?<?0.001) glutathione peroxidase activity in blood. Furthermore, at the end of the trial, serum tri-iodothyronine (T3) amount also increased (P?<?0.05), while serum thyroxine (T4) amount decreased (P?<?0.05). Digestibility of dry matter, organic matter, crude protein, neutral detergent fiber, and acid detergent fiber increased (P?<?0.05) by Se yeast supplementation. It may be concluded that supplementation of Se in lambs had no significant effect on performance and blood hematology, but increased blood glutathione peroxidase activity and serum T3 amount and decreased serum T4 amount as compared to non-supplemented control lambs. Furthermore, Se yeast improved nutrient digestibility in lambs.  相似文献   
844.
Selenium supplementation still enhanced the immune response even in individuals who, according to current standards, would be considered as not being overtly selenium deficient. Mast cells are granulated cells that play a pivotal role in allergic reactions. In this study, we investigated the modulatory effect of sodium selenite on mediator release and degranulation of murine mast cell line (MC/9). Cells were pre-treated with selenium selenite (1, 2, 3 μg/ml) for 24 h and controls left untreated. Then, cells were sensitized overnight with anti-dinitrophenyl (DNP) IgE and challenged with DNP/HSA for degranulation induction. The histamine and prostaglandin D2 (PGD2) were measured by ELISA, and β-hexosaminidase was measured by spectrophotometery method. Selenium-treated cells revealed significant decrease in concentration of PGD2 (P?=?0.019) and β-hexosaminidase (P?=?0.009). In addition, a slight reduction of histamine release by the selenium-treated cells was observed, based on our intracellular and extracellular assessments. The most inhibitory effect of selenium supplementation on mediator release of MC/9 cells was obtained in the presence of 3 μg/ml of sodium selenite. The results of the present study demonstrate beneficial effects of supplemental selenium in attenuating clinical manifestations of allergy and asthma.  相似文献   
845.
The aim of this study was to examine whether the relative gene expression of AdipoR1 and AdipoR2 in rat adipose tissue is altered by thyroid hormones, and whether this might relate to their circulating thyroid hormones and adiponectin levels. Hyper- and hypothyroidism were induced by daily oral administration of levothyroxine and methimazole in rats, respectively, over a 42 days period. Real-time PCR analysis was performed to evaluate the changes in AdipoR1 and AdipoR2 mRNA levels in the adipose tissue on days 15, 28, 42, and also 2 weeks after the cessation of treatment. In response to treatment with methimazole, mRNA levels of AdipoR1 and AdipoR2 decreased in the white adipose tissue compared to the euthyroid rats (p < 0.05). This decline was reversible 2 weeks after treatment cessation. The mRNA levels of AdipoR1 and AdipoR2 were increased in the hyperthyroid group of animals compared to euthyroid control (p < 0.05), and its changes were reversible 2 weeks after treatment cessation (P < 0.05). Adiponectin receptors gene expression levels in the adipose tissue of treated animals have positive correlations with thyroid hormones concentrations. Our results suggest that AdipoR1 and AdipoR2 gene expression is regulated by thyroid hormones in hypo- and hyperthyroidism.  相似文献   
846.
In diagnostic research challenges, quantitative real-time PCR (QPCR) has been widely utilized in gene expression analysis because of its sensitivity, accuracy, reproducibility, and most importantly, quantitativeness. Real-time PCR base kits are wildly applicable in cancer signaling pathways, especially in cancer investigations. T-cell acute lymphoblastic leukemia (T-ALL) is a type of leukemia that is more common in older children and teenagers. Deregulation of the Notch signaling pathway promotes proliferation and inhibits apoptosis of the lymphoblastic T cells. The aim of this study was to investigate the effect of Notch signaling activation on the expression of target genes using real-time QPCR and further use this method in clinical examination after validation. Two T-ALL cell lines, Jurkat and Molt-4, were used as models for activation of the Notch signaling via over-expression of the Notch1 intracellular domain. Expression analysis was performed for six downstream target genes (NCSTN, APH1, PSEN1, ADAM17, NOTCH1 and C-MYC) which play critical roles in the Notch signaling pathway. The results showed significant difference in the expression of target genes in the deregulated Notch signaling pathway. These results were also verified in 12 clinical samples bearing over-expression of the Notch signaling pathway. Identification of such downstream Notch target genes, which have not been studied inclusively, provides insights into the mechanisms of the Notch function in T cell leukemia, and may help identify novel diagnoses and therapeutic targets in acute lymphoblastic leukemia.  相似文献   
847.
The Sunn pest, Eurygaster integriceps, the bird cherry-oat aphid, Rhopalosiphum padi, and wheat thrips, Haplothrips tritici are the major pests of wheat and other cereals in a wide area of the world. All these three insect species could produce damage to the wheat to some extent. Therefore, the purpose of the present study was to determine α- and β-mannosidase of the three mentioned insect pests. These insects were collected from the wheat farm and their guts (the Sunn pest and the aphid) and salivary glands of Sunn pest were removed. However, regarding tiny body of thrips, the whole body used in order to extract the enzymes. The enzymes, including α- and β-mannosidase activity, were measured by the hydrolysis of p-nitrophenyl-α-d-mannopyranoside (pNPαGal) and p-nitrophenyl-β-d-mannopyranoside (pNPβGal), respectively, using phosphate citrate buffer (pH 5.0). Mannosidases were not active in all three tested insect species, and also there were significant differences in activities of the two enzymes in three species. The greatest activity of α-mannosidases was observed in the Sunn pest salivary glands, E. integriceps, and the least activity was found in Sunn pest midgut with no activity. However, the activity of β-mannosidase was established in Sunn pest midgut, but there was no activity in the aphid midgut, R. padi. Activities of these two enzymes were modest in the thrips, H. tritici. The greatest amount of β-mannosidases in the Sunn pest midgut makes sense, since the Sunn pest is the main pest in the wheat farm that can feed on wheat grains. In the wheat grains, the highest amount of glycoproteins and glycolipids are present. Thus, it has been known that these enzymes (α- and β-mannosidases) are active on digestion of carbohydrates.  相似文献   
848.
Sugar beet roots and the attached soil are transferred to Bardsir factory for processing, and the roots are washed by water pressure. Muddy water flows as waste into canals and are used for irrigation of sugar beet farms. The possibility of occurrence and fluctuations of the pathogenic organisms in irrigation was studied during 2006 and 2007. The samples were collected from the wastewater once a week. Isolation of pathogens was done by four methods: (a) Citrus leaf baiting method and on PARPH selective medium, and common culture media such as: PDA, CMA, MA, NA and WA; (b) Irrigation of sugar beet seedling with wastewater; (c) Bioassay with healthy sugarbeet roots; (d) Cysts of nematode were extracted from waste by sieves. Many different pathogens were isolated from wastewater such as: Fusarium oxysporum, Fusarium solani, Rhizopus stolonifer, Penicillium digitatum, Aspergillus niger, Pythium aphanidermatum, Pythium akanoganese, Phytophthora cryptogea, Phytophthora drechsleri, Mucor sp., Rhizoctonia solani, Geotrichum sp., Erwinia carotovora and cysts of Heterodera schachtii. Pathogencity tests were done for each pathogen. During the first period of processing, the recovery of pythiaceae and Erwinia carotovora was in high level, and in the last period of processing the recovery of Penicillium digitatum, Aspergillus niger, Mucor sp. and Geotrichum sp. showed high levels. The recovery of Alternaria alternata, Rhizoctonia solani and Fusarium solani were stable but the cysts of H. schachtii were variable during the processing period. These pathogens were isolated from sugar beet farms irrigated with wastewater.  相似文献   
849.
Ficus benjamina, commonly known as weeping fig, Benjamin’s fig or Ficus tree is a species of flowering plant in the family of Moraceae. It is native to south and south-east Asia and Australia. Crown gall tumours were collected from branches of one-year-old weeping fig (F. benjamina L.) trees. A total of 50 strains of Agrobacterium tumefaciens were isolated from diseased Ficus plants and their morphological, molecular and biochemical characteristics were studied; pathogenicity tests on tomato, F. benjamina and Bryophyllum daigremontianum were also conducted. Based on the biochemical characteristics, pathogenicity test and PCR amplification of 730?bp fragment using VCR\VCF primers, the tested bacterial strains were identified as A. tumefaciens. This is the first report of crown gall on F. benjamina in Isfahan and Fars provinces of Iran.  相似文献   
850.
Chemokines, a subclass of cytokine superfamily have both pro-inflammatory and migratory role and serve as chemoattractant of immune cells during the inflammatory responses ensuing spinal cord injury (SCI). The chemokines, especially CXCL-1, CXCL-9, CXCL-10 and CXCL-12 contribute significant part in the inflammatory secondary damage of SCI. Inhibiting chemokine’s activity and thereby the secondary damage cascades has been suggested as a chemokine-targeted therapeutic approach to SCI. To optimize the inhibition of secondary injury through targeted chemokine therapy, accurate knowledge about the temporal profile of these cytokines following SCI is required. Hence, the present study was planned to determine the serum levels of CXCL-1, CXCL-9, CXCL-10 and CXCL-12 at 3–6 h, 7 and 28 days and 3 m after SCI in male and female SCI patients (n = 78) and compare with age- and sex-matched patients with non-spinal cord injuries (NSCI, n = 70) and healthy volunteers (n = 100). ANOVA with Tukey post hoc analysis was used to determine the differences between the groups. The data from the present study show that the serum level of CXCL-1, CXCL-9 and CXCL-10 peaked on day 7 post-SCI and then declined to the control level. In contrast, significantly elevated level of CXCL-12 persisted for 28 days post SCI. In addition, post-SCI expression of CXCL-12 was found to be sex-dependent. Male SCI patients expressed significantly higher CXCL-12 when compared to control and SCI female. We did not observe any change in chemokines level of NSCI. Further, the age of the patients did not influence chemokines expression after SCI. These observations along with SCI-induced CSF-chemokine level should contribute to the identification of selective and temporal chemokine targeted therapy after SCI.  相似文献   
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