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131.
The aim of this study was to assess the ultrasonographic characteristics of ovulatory follicles in cyclic Western White Face ewes (December) that had received intravaginal sponges containing medroxyprogesterone acetate (MAP; 60 mg) for 12 days, with or without an injection of 500 IU of equine chorionic gonadotropin (eCG) at sponge removal. We hypothesized that quantitative echotextural attributes of the follicles in ewes treated only with MAP would differ from those in MAP/eCG-treated ewes, reflecting the increased antral follicular growth and secretory function under eCG influence. Digital images of ovulatory follicles obtained at 0 and 24 h after MAP sponge removal and at 24 h before ovulation in the eCG-treated (five ewes, 13 follicles) and control (six ewes, 9 follicles) animals, were subjected to computerized analyses. The mean diameter of ovulatory follicles increased (p < 0.001) 24 h after eCG treatment. The mean pixel intensity and heterogeneity of the follicular antrum (p < 0.001), as well as mean pixel intensity of the follicular wall and perifollicular ovarian stroma (p < 0.05), were greater in eCG-treated animals compared with control ewes 24 h after sponge removal and at 24 h before ovulation. Mean serum concentrations of oestradiol-17beta tended to increase (p = 0.06) 24 h after eCG treatment and the eCG-treated ewes exceeded (p < 0.05) control animals in progesterone concentrations from days 9-15 after ovulation. Our results support the hypothesis that large antral follicles in eCG-treated ewes exhibit distinctive echotextural characteristics. Follicular image attributes in eCG-treated ewes appear to be indicative of the changes in follicular morphology and secretory activity caused by the administration of the exogenous gonadotropin, which has both FSH- and LH-like activities.  相似文献   
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133.
Fibroblast growth factor (FGF10) acts at the cumulus oocyte complex, increasing the expression of cumulus cell expansion‐related genes and oocyte competency genes. We tested the hypothesis that addition of FGF10 to the maturation medium improves oocyte maturation, decreases the percentage of apoptotic oocytes and increases development to the blastocyst stage while increasing the relative abundance of developmentally important genes (COX2, CDX2 and PLAC8). In all experiments, oocytes were matured for 22 h in TCM‐199 supplemented with 0, 2.5, 10 or 50 ng/ml FGF10. In Experiment 1, after maturation, oocytes were stained with Hoechst to evaluate meiosis progression (metaphase I, intermediary phases and extrusion of the first polar body) and submitted to the TUNEL assay to evaluate apoptosis. In Experiment 2, oocytes were fertilized and cultured to the blastocyst stage. Blastocysts were frozen for analysis of COX2, CDX2 and PLAC8 relative abundance. In Experiment 1, 2.5 ng/ml FGF10 increased (p < 0.05) the percentage of oocytes with extrusion of the first polar body (35%) compared to 0, 10 and 50 ng/ml FGF10 (21, 14 and 12%, respectively) and FGF10 decreased the percentage of oocytes that were TUNEL positive in all doses studied. In Experiment 2, there was no difference in the percentage of oocytes becoming blastocysts between treatments and control. Real‐time RT‐PCR showed a tendency of 50 ng/ml FGF10 to increase the relative abundance of COX2 and PLAC8 and of 10 ng/ml FGF10 to increase CDX2. In conclusion, the addition of FGF10 to the oocyte maturation medium improves oocyte maturation in vitro, decreases the percentage of apoptotic oocytes and tends to increase the relative abundance of developmentally important genes.  相似文献   
134.
The chloroform-acetone mixture (4:1, v/v) was an effective solvent for eluting the nonpolar lipid fraction, including free fatty acids, from the polar lipid (glycolipid and phospholipid) fractions from free lipids of 21 hard winter wheat flours using a solid-phase extraction system. Amounts of monogalactosyldiglycerides (MGDG) and digalactosyldiglycerides (DGDG) in the glycolipid fraction were determined by normal-phase HPLC with a gradient system using an evaporative light-scattering detector (ELSD) and a diode array detectors (DAD). Unsaturated fatty acids showed higher UV absorbances from 200 to 213 nm when compared with saturated palmitic acid. However, significant linear correlation coefficients were obtained between the peak areas measured by a DAD and GL contents determined by an ELSD, suggesting that fatty acid composition of flour GL could be fairly constant. Using an ELSD as a reference, equations for determination of MGDG or DGDG quantities were derived from the peak areas of a DAD by multivariate regression methods. Determination of MGDG and DGDG quantities was also possible using only a DAD.  相似文献   
135.
ABSTRACT

Aims To compare wound healing 7 days after cautery disbudding of dairy calves treated immediately after disbudding with a traditional antimicrobial spray (OXY) or with a topical anaesthetic gel containing cetrimide, adrenaline and two local anaesthetics, lignocaine and bupivacaine (TA).

Method Eighty-one female dairy calves between 6–8 weeks of age were disbudded using a standard cautery disbudding protocol (sedation, cornual block, and analgesia), with complete removal of the horn bud. After disbudding, the wound on the right and left horn buds within each animal were randomly allocated to receive either OXY or TA. One week after disbudding, wounds were visually assessed for the presence of exudate, necrotic tissue, crust, or granulation tissue which were each assigned a grade from 1–3, where 1?=?no evidence, 2?=?moderate presence; and 3?=?marked presence.

Results At 7 days after disbudding, the prevalence of wounds with exudate or necrotic tissue was very low, and independent of treatment. The odds of a disbudding wound treated with TA being scored as having granulation tissue and was 5.2 (95% CI?=?1.72–15.7) times that of a wound treated with OXY. Conversely, the odds of wounds treated with TA being scored as having crusts was 0.18 (95% CI?=?0.06–0.57) that of a wound treated with OXY. No sign of infection was seen in any calves.

Conclusion and clinical relevance The greater prevalence of granulation tissue and reduction in crusting in disbudding wounds treated with topical anaesthetic gel compared to those treated with the antimicrobial spray suggests that use of the topical anaesthetic gel may speed wound healing compared to using antimicrobial spray. This should be further tested in a larger study undertaken over a longer period.  相似文献   
136.
Molecular weight distribution (MWD) of proteins extracted from hard red spring wheat was analyzed by size‐exclusion HPLC to investigate associations with wheat and breadmaking quality characteristics. Certain protein fractions were related to associations between wheat and breadmaking parameters, specifically when effect of quantitative variation of protein on those parameters was statistically eliminated by partial correlation analysis. SDS‐unextractable high molecular weight polymeric proteins had positive partial correlations with percent vitreous kernel content and breadmaking parameters, including mix time and bread loaf volume. SDS‐extractable protein fractions that were eluted before the primary gliadin peak had positive partial correlations with kernel hardness and water absorption parameters. The proportion of main gliadin fractions in total protein had a negative partial correlation with bread loaf volume and positive correlations with kernel hardness and water absorption parameters. Intrasample uniformity in protein MWD and kernel characteristics was estimated from three kernel subsamples that were separated according to single kernel protein content within individual wheat samples by a single‐kernel near‐infrared sorter. Wheat subsamples were significantly different in protein MWD. Intrasample uniformity in protein MWD did not differ greatly among wheat samples.  相似文献   
137.
138.
An experiment was conducted to investigate the effect of plasma concentrations of the metabolic hormones [Growth hormone (GH), insulin and insulin‐like growth factor –I (IGF‐I)] and nutritional metabolites (Glucose, cholesterol, total protein, albumin, globulin, urea and creatinine) on the resumption of post‐partum ovarian activity in sixteen Friesian–Sanga cows grazing extensively on native grassland. Blood samples were taken from cows from week 1 to 16 post‐partum. Cows were classified as having resumed ovarian activity when a plasma progesterone concentration of ≥ 1.0 ng/ml was recorded for two consecutive weekly samples. Based on the resumption of ovarian activity, cows were classified as early‐cycling, late‐cycling or non‐cycling. The concentrations of the metabolic hormones were measured from week 1 to 10, while those of the nutritional metabolites were measured during week 1, 3, 5, 7 and 9 during the study period. The concentrations of the metabolic hormones, GH and insulin were similar (p > 0.05) in the three ovarian activity groups, likewise the concentrations of the nutritional metabolites, glucose, total protein, globulin, urea and creatinine. Plasma IGF‐I concentration was higher (p < 0.001) in early‐cycling (18.7 ± 0.74 ng/ml) than in late‐cycling (12.4 ± 0.75 ng/ml) and non‐cycling (10.4 ± 0.91 ng/ml) cows. Plasma cholesterol concentrations were significantly lower (p < 0.05) in early‐cycling (1.94 ± 0.15 mmol/l) compared with late‐cycling (2.48 ± 0.12 mmol/l) and non‐cycling (2.61 ± 0.11 mmol/l) cows. For plasma albumin concentrations, the levels recorded for early‐cycling cows were higher (40.7 ± 2.85 g/l) than in late‐cycling (34.4 ± 1.97 g/l) and non‐cycling (33.6 ± 2.66) cows. The results suggest that cows with lower plasma concentrations of IGF‐I and albumin, but higher plasma cholesterol concentrations were at risk of delayed resumption of post‐partum ovarian activity.  相似文献   
139.
A nonlinear demographic model was used to predict the population dynamics of the flour beetle Tribolium under laboratory conditions and to establish the experimental protocol that would reveal chaotic behavior. With the adult mortality rate experimentally set high, the dynamics of animal abundance changed from equilibrium to quasiperiodic cycles to chaos as adult-stage recruitment rates were experimentally manipulated. These transitions in dynamics corresponded to those predicted by the mathematical model. Phase-space graphs of the data together with the deterministic model attractors provide convincing evidence of transitions to chaos.  相似文献   
140.
Airborne measurements in smoke from biomass burning in Brazil have yielded optical parameters that permit an improved assessment of the effects of smoke on Earth's radiation balance. The global-mean direct radiative forcing due to smoke from biomass burning worldwide is estimated to be no more than about -0.3 watt per square meter (cooling), compared with +2.45 watts per square meter (warming) due to anthropogenic greenhouse gases. On regional scales, direct radiative forcing due to smoke can be large and might indirectly affect global climate.  相似文献   
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