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Background: The ovariectomized animals are good models to evaluate the effect of different steroid hormone treatments on implantation events and the pattern of integrin expression. Therefore, this study was performed to compare the expression of integrins and osteopontin (OPN) in correlation with pinopode development in ovariectomized mice endometrium which was subjected to steroid hormones. Methods: Ovariectomized mice were subjected to estrogen, progesterone and estrogen-progesterone hormones. Their uterine horns were evaluated for integrin expression by immunohistochemistry and real-time RT-PCR and for pinopode development by transmission and scanning electron microscopic studies. Results: No immunostaining for integrin and OPN molecules were detected in the endometrium of non-ovariectomized mice except in metestrus phase. The α4 and β1 integrin genes were expressed in all phases of estrous cycle. In ovariectomized mice, no reaction was detected in the endometrium of control, sham and estrogen-treated groups, but in both progesterone-treated groups, all examined genes were expressed. There was not any correlation between pinopodes and integrin expression in ovariectomized mice. Conclusion: The progesterone is more effective on endometrial integrin expression than estrogen and differences in the expression pattern of integrins reflect their important and different roles in embryo implantation. The pinopodes may have minor effect in mice implantation or have some delay in their expressions in ovariectomized mice which were subjected to exogenous hormones. Key Words: Endometrium, Estrogen, Integrin, Ovariectomized mice, Osteopontin (OPN)  相似文献   
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Devil's claw is used for the treatment of inflammatory symptoms and degenerative disorders in horses since many years, but without the substantive pharmacokinetic data. The pharmacokinetic parameters of harpagoside, the main active constituent of Harpagophytum procumbens DC ex Meisn., were evaluated in equine plasma after administration of Harpagophytum extract FB 8858 in an open, single‐dose, two‐treatment, two‐period, randomized cross‐over design. Six horses received a single dose of Harpagophytum extract, corresponding to 5 mg/kg BM harpagoside, and after 7 days washout period, 10 mg/kg BM harpagoside via nasogastric tube. Plasma samples at certain time points (before and 0–24 hr after administration) were collected, cleaned up by solid‐phase extraction, and harpagoside concentrations were determined by LC‐MS/MS using apigenin‐7‐glucoside as internal standard. Plasma concentration‐time data and relevant parameters were described by noncompartmental model through PKSolver software. Harpagoside could be detected up to 9 hr after administration. Cmax was found at 25.59 and 55.46 ng/ml, t1/2 at 2.53 and 2.32 hr, respectively, and tmax at 1 hr in both trials. AUC0–inf was 70.46 and 117.85 ng hr ml?1, respectively. A proportional relationship between dose, Cmax and AUC was observed. Distribution (Vz/F) was 259.04 and 283.83 L/kg and clearance (CL/F) 70.96 and 84.86 L hr?1 kg?1, respectively. Treatment of horses with Harpagophytum extract did not cause any clinically detectable side effects.  相似文献   
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The aim of the present study was to evaluate the status of inorganic phosphorus (P) fractions in ten virgin soil profiles, and to study the relationships between P fractions and soil properties from Kohgyloyeh and Boir Ahmad province, Iran. The soils belonged to Alfisols, Entisols, Mollisols, and Inceptisols. Mean annual precipitation and temperature ranges were 450–850 mm and 12.2–22.4°C, respectively. Inorganic P was fractionated by sequential extraction with NaHCO3, NH4OAc, MgCl2, NH4F, NaOH, citrate-dithionite-bicarbonate (CBD), and H2SO4, which are referred to as NaHCO3–P, NH4OAc–P, MgCl2–P, NH4F–P, NaOH–P, CBD–P, and H2SO4–P, respectively. Generally, the NaHCO3–P, NH4OAc–P, MgCl2–P, and NH4F–P were higher in surface horizons, especially wherever there was higher annual precipitation. Results showed that H2SO4–P constituted the largest inorganic P fractions in all profiles. For all the soils studied the distribution of P fractions was similar to that of weakly weathered soils under arid and semi-arid regions which represent an early stage of development. Pedogenic P compounds were higher where weathering was higher, i.e., in surface horizons and at higher annual precipitation.  相似文献   
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Two barley cultivars (‘Sahara’ = Zn-efficient and ‘Clipper’ = Zn-inefficient) were grown at different soil Zn fertilization (0, 0.2, 0.8, 1.6 and 3.2 mg Zn kg?1 soil). Root exudates were collected 16 and 28 days after sowing. At Zn = 0, shoot dry matter was decreased in both genotypes, but more distinctly in ‘Clipper’. At 0.2 mg Zn kg?1, the ‘Sahara’ shoot concentrations of Zn was 130% higher and shoot Zn content 44% greater compared with ‘Clipper’. Low-molecular-weight organic acid anions (=carboxylates) (malate, maleate, fumarate and cis-aconitate) and amino acids (alanine, valine, proline, aspartic acid and glutamic acid) were detected in root exudates, with the highest concentration at Zn = 0.2 mg kg?1 soil. Higher concentrations of organic acid anions as well as amino acids were noted in the rhizosphere of ‘Sahara’ than ‘Clipper’. The genotypic differences in Zn acquisition from soil may be linked to differential carboxylate and amino acid composition of root exudates.  相似文献   
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In this study, changes in the chemical composition, pH, cell wall and degradability of ensiled rice straw were investigated when treated with alkali, acid, oxidant agents (1–11 %, w/w) and a combination of an oxidant with either an alkali (ALHP) or an acid (ACHP). The findings of the study revealed that ALHP had a lower efficiency in enhancing fibre degradability compared to alkali alone. Oxidant treatment showed no detectable changes in pH, dry matter (DM) and phenolic compound (PC) solubility, or in silica and fibre content, but led to increased esterified groups formed within the cell wall constituents (hemicellulose and lignin). Increasing acid concentration led to an exponential change in both pH and solubility of DM and hemicelluloses while it quadratically increased PC and silica solubility. Moreover, crystallinity, hydrogen bonding and esterification were enhanced under high acid concentrations (11 %), but decreased under mild acid conditions (5 %). Increased alkalinity led to the linear enhancement of DM and PC solubility. Solubility of silica and hemicellulose did not exhibit any significant changes with alkali concentration above 7 %. A gradual enhancement (29 %) was observed in ruminal DM degradability with increasing oxidant concentration, whereas exponential (91 %) and quadratic (23 %) enhancements were observed with alkaline and acid treatments, respectively. Treatment with acid showed observable reductions in the degradability of both cellulose and hemicellulose, whereas oxidant treatment reduced only that of hemicellulose. Treatment with 7 % alkali (pH?~?12) followed by ensiling appeared to be a promising process for improving rice straw quality.  相似文献   
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ABSTRACT

Soil amendment with biochar could increase soil microbial activity and biomass. This study contributes to an understanding of the synergistic effects of biochar and phosphate solubilizing microorganisms on safflower yield and soil microbial activity enhancement. In the split plot experiments that repeated in two years, the main factor was biochar types included cow manure, wheat straw, wood biochar and control. The sub factors were phosphate solubilizing microorganisms included the mycorrhizal fungi (Glomus etunicatum and G. mosseae), Bacillus lentus, Pseudomonas fluorescence and control. The highest levels of dehydrogenase, urease activity and microbial biomass carbon were obtained from the cow manure biochar. The maximum activity of acid phosphatase was in the plots inoculated by P. fluorescence in all treatments, whether using or not using biochar. The grain yield of plants inoculated with B. lentus and P. fluorescence was in the same statistical group. The highest grain yield equal to 1527 kg/ha was obtained when using cow manure biochar. According to the results, the application of cow manure biochar and phosphate solubilizing microorganisms, especially mycorrhiza species, can be recommended for improving soil biological traits and safflower yield traits.  相似文献   
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Journal of Crop Science and Biotechnology - It is exceptionally difficult to have productive farming without the use of herbicides. It has been found that they create difficulties in the growth and...  相似文献   
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