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The utilization of Hura crepitans seed oil in the formulation of alkyd resins was investigated using a two-stage alcoholysis-polyesterification method. The percentage yield of the oil was 36.4%; and the physicochemical characterization revealed that the seed oil is an unsaturated semi-drying oil. The fatty acid profile of the oil showed that it contains linoleic acid (81.6%) as the most abundant fatty acid, and two other fatty acids: palmitic acid (16.92%) and stearic acid (1.76%). Short (I), medium (II) and long (III) oil alkyds were synthesized using the oil, glycerol and phthalic anhydride in different ratios. Properties of the three prepared samples of H. crepitans seed oil alkyds having oil content of 30% (I), 50% (II), and 65% (III) were evaluated. The alkyd resins synthesized compared favourably with the commercially available alkyd resin. The presence of unsaturation in the oil was confirmed by infra-red peak at 2930 cm−1 attributed to CC stretch. The infra-red peaks of the sample also compared well with that of the commercial sample indicating that H. crepitans seed oil has been successfully converted to alkyd resin. Evaluation of prepared alkyds by determination of acid values, solubility in butanol and toluene, resistance of dry film to acid, alkali and water, and drying time revealed that H. crepitans seed oil is a potential raw material for the coating industry.  相似文献   
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Effect of soybean (Glycine max) on serum level of some sex hormones: testosterone, follicle stimulating hormone (FSH), luteinizing hormone/interstitial cell stimulating hormone (LH/ICSH), estradiol and prolactin in male rats was investigated. Twenty male albino rats of 12 weeks old with similar body weights were assigned to four groups of 5 rats each and treatment with soybean meal at 100, 200 and 300 mg kg(-1) body weight, respectively daily for 8 weeks. Blood samples collected through cardiac puncture were assayed for levels of hormones. There were dose-dependent effects of the soybean meal on the serum concentration of the hormones. The treatment significantly reduced the levels of testosterone and FSH in the serum while it significantly increased the levels of estradiol, LH/ICSH and prolactin. The results show that soybean (Glycine max) had strong capability to disrupt hormonal functions. Hence, its indiscriminate use could increase the risk of infertility in males.  相似文献   
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Strategic supplementation of P4 may be used to increase conception rates in cattle, but timing of supplementation in relation to ovulation, mass of supplementary P4 and formulation of the P4‐containing supplement has not been determined for beef cattle. Effects of supplementation of long‐acting progesterone (P4) on Days 2 or 3 post‐ovulation on development, function and regression of corpus luteum (CL) were studied in beef cattle. Cows were synchronized with an oestradiol/P4‐based protocol and treated with 150 or 300 mg of long‐acting P4 on Day 2 or 3 post‐ovulation (6–7 cows/group). Colour‐doppler ultrasound scanning and blood sample collection were performed from Day 2–21.5. Plasma P4 concentrations were greater (p < 0.05) from Day 2.5–5.5 in the Day 2‐treated groups and from Day 3.5–5.5 in the Day 3‐treated cows than in the control group. CL area and blood flow during Day 2–8.5 did not differ (p > 0.05) among groups, suggesting no effect of P4 treatment on luteal development. The frequency of cows that began luteolysis before Day 15 was greater (p < 0.04) in cows treated with 300 mg than in the controls, but there were no differences between non‐treated and 150 mg‐treated cows. The interval from pre‐treatment ovulation to functional and structural luteolysis was shorter (p < 0.01) in the combined P4‐treated groups than in the control cows. In conclusion, was showed for the first time that long‐acting P4 supplementation on Day 2 or 3 post‐ovulation increases P4 concentrations for ≥3 day, has no effect on luteal development, but anticipates the beginning of luteolysis in beef cattle.  相似文献   
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The ovarian follicle components must provide an ideal environment to ensure the success of reproductive processes, and communication between follicular cells is crucial to support proper oocyte growth. Recently, it has been demonstrated that the presence of extracellular vesicles (EVs) carrying microRNAs (miRNAs) in follicular fluid represents an important autocrine and paracrine communication mechanism inside the ovarian follicle. In this study, we tested the hypothesis that the miRNA content of EVs isolated from ovarian follicular (granulosa and cumulus–oocyte complexes) cell‐conditioned culture media is dependent upon cell type. We initially screened bovine granulosa cells (GCs) and cumulus–oocyte complexes (COCs), as well as their derived EVs for 348 miRNAs using real‐time PCR, and detected 326 miRNAs in GCs and COCs cells and 62 miRNAs in GCs and COCs EVs. A bioinformatics analysis of the identified cell‐specific and differentially expressed miRNAs predicted that they likely modulate important cellular processes, including signalling pathways such as the PI3K‐Akt, MAPK and Wnt pathways. By investigating the origins of miRNAs within the follicular fluid, the results of this study provide novel insights into follicular miRNA content and intercellular communication that may be of invaluable use in the context of reproductive technologies, diagnostic of ovarian‐related diseases and/or the identification of biomarkers for oocyte and embryo quality.  相似文献   
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Proximate composition, mineral element content, amino acid profile and the levels of some antinutrients in the edible leaves ofPterocarpus mildbraedii were determined. Moisture content was assayed as 85.12 percent (wet weight). Protein, fat, ash and fibre contents of the leaf (percent dry weight) were 25.84, 5.23, 6.44 and 7.56 respectively. Mineral element analysis showed high levels of calcium, potassium, magnesium, iron, copper, manganese and zinc. However, the level of sodium in the vegetable was low. Amino acid profile indicated that the leaf is rich in essential amino acids. The antinutrient levels of hydrogen cyanide and oxalate were low. The paper suggests the need to meet nutrient requirements through an increased use of this cheap but less popular food item with good nutritive potential.  相似文献   
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The effects of ethanol extracts of Bridelia ferruginea leaves and stem bark on purinergic neurotransmission in the rat bladder were investigated. The stem bark extract potentiated the contraction of the bladder evoked by exogenous adenosine 5-triphosphate (ATP) but depressed KCl-induced contractions in a dose-related pattern; these two opposite actions might account for the lack of effect on field stimulation of the bladder purinergic nerves. The leaf extract depressed purinergic nerve-mediated contraction of the rat bladder in a dose-related fashion. This action could be attributed to blockade of purinergic neurotransmission since the leaf extract did not affect KCl-induced contractions.  相似文献   
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