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排序方式: 共有195条查询结果,搜索用时 31 毫秒
121.
X Liu Q Dai EJ Hart DMW Barrett NC Rawlings RA Pierson PM Bartlewski 《Reproduction in domestic animals》2007,42(4):393-401
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
122.
Determination of influence of food intake after a single oral dose of mosapride in beagle dogs using nonlinear mixed effect modeling
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I.‐H. Baek S. Pradhan B. Song H.‐M. Back M. Yun C. Pai J. S. Bang H.‐Y. Yun W. Kang K.‐I. Kwon 《Journal of veterinary pharmacology and therapeutics》2015,38(6):590-595
The objective of this study was to describe the population pharmacokinetics (PK) of mosapride under fasting and fed conditions. A single 5‐mg oral dose of mosapride was administered to fasted (n = 15) and fed (n = 12) beagle dogs. Plasma concentrations of mosapride were subsequently measured by liquid chromatography–tandem mass spectrometry. Data were analyzed using modeling approaches with the NONMEM 7.2 software. A one‐compartment open PK model utilizing model event time (MTIME) with first‐order absorption and first‐order elimination was found to be more appropriate than all other PK models tested. The absorption rate constants of mosapride were significantly decreased under fed conditions, compared to fasting conditions. The observed bootstrap medians of PK parameters were generally consistent with the corresponding population mean estimates. Furthermore, with the exception of some mosapride concentrations, most of observed data fell into the range of the 5th and 95th percentiles of the simulated values. Overall, the final model was able to describe the observed mosapride concentrations reasonably well. These findings suggest that food intake affects both the rate and extent of absorption of mosapride and that the pharmacological effect of mosapride can differ significantly depending on food intake. 相似文献
123.
EJ Steig EJ Brook JWC White CM Sucher ML Bender SJ Lehman DL Morse ED Waddington GD Clow 《Science (New York, N.Y.)》1998,282(5386):92-95
Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events-the rapid warming that marks the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation-are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres. 相似文献
124.
Valeria Orlando Ivan G. Grove Simon G. Edwards Thomas Prior David Roberts Roy Neilson Matthew Back 《Plant pathology》2020,69(3):405-417
Root-lesion nematodes of the genus Pratylenchus are migratory endoparasites with worldwide economic impact on several important crops including potato, where certain species like P. penetrans, P. neglectus, and P. scribneri reduce the yield and quality of potato tubers. Morphological identification of Pratylenchus spp. is challenging, and recent advancements in molecular techniques provide robust and rapid diagnostics to differentiate species without the need of specialist skills. However, the fact that molecular diagnostics are not available for all Pratylenchus species means that there are limitations in worldwide application. In general, root-lesion nematodes are difficult to manage once introduced into agricultural land and damage can be related to pathogenicity and population densities. In addition, root-lesion nematodes interact with fungi such as Verticillium dahliae, resulting in disease complexes that enhance the damage inflicted on the potato crop. Management interventions are often focused on limiting nematode reproduction before planting crops and include the application of nematicides, and cultural practices such as crop rotation, cover crops, biofumigation, and biological control. Understanding the limitations of the available crop protection strategies is important and there are many gaps for further study. This review discusses the status of the diagnosis, distribution, pathogenicity, and management of the main species of root-lesion nematodes, reported to infect potatoes worldwide, and highlights areas for potential future research. 相似文献
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Background Benign mixed tumours (BMTs) are frequently found in the mammary glands of female dogs, but the factors determining malignant transformation in these tumours are unknown. Objective To evaluate the expression of the oncoproteins, human epidermal growth factor receptor 2 (HER‐2) and epidermal growth factor receptor (EGFR), in 46 carcinomas in BMTs (CBMTs) and to verify their possible association with the malignancy of the tumours. Methods Immunohistochemical expression was analysed in benign and malignant components separately, and then compared with 74 cases of BMTs. Results Among the CBMTs, positivity for HER‐2 was found in the benign histological component of 4.3% (2/46), in the malignant epithelial non‐invasive component of 14.8% (4/27) and in the malignant invasive epithelial component of 13.6% (6/44) of cases. Two of the 24 (8.3%) BMTs were positive for HER‐2. There was no relationship between HER‐2 and the tumour components. There was no significant difference between BMTs and CBMTs. Positivity for EGFR was found in the benign component of 17.4% (8/46) of the CBMTs, in the malignant epithelial non‐invasive component of 40.7% (11/27%) and in the invasive epithelial malignant component of 45.4% (20/44). EGFR positivity was significantly associated with the invasive component of CBMTs. Conclusion EGFR may contribute to malignant epithelial transformation of BMTs. In contrast, HER‐2 overexpression may not be associated with the acquisition of a malignant epithelial phenotype. 相似文献
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MJ Thompson J Toomre ER Anderson HM Antia G Berthomieu D Burtonclay SM Chitre J Christensen-Dalsgaard T Corbard M DeRosa CR Genovese DO Gough DA Haber JW Harvey F Hill R Howe SG Korzennik AG Kosovichev JW Leibacher FP Pijpers J Provost EJ Rhodes J Schou T Sekii PB Stark PR Wilson 《Science (New York, N.Y.)》1996,272(5266):1300-1305
Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes. 相似文献
130.
PE Fernández ME Diessler A Pachame HH Ortega EJ Gimeno EL Portiansky CG Barbeito 《Reproduction in domestic animals》2014,49(2):263-269
The aim of this study was to characterize cytoskeletal intermediate filament proteins and glycoconjugates of syncytiotrophoblast, cytotrophoblast and decidual cells of feline endotheliochorial placenta. Samples from 12 normal pregnant female cats, after 45 ± 5 days of gestation, were obtained removing the uterine horns by hysterectomy. Sections were processed for routine observation and for immunohistochemistry using anticytokeratin, antivimentin and antidesmin antibodies. In addition, lectin histochemistry was performed using a panel of several biotinylated lectins to characterize glycosides expression profile. Cytotrophoblast and syncytiotrophoblast showed immunoreactivity only with acidic and basic cytokeratins. Decidual cells were only positive to vimentin, consistent with their origin from endometrial fibroblasts. Trophoblast expressed a broad population of glycans, highly exposing terminal N‐acetyl glucosamine residues and non‐sialylated galactose and N‐acetyl galactosamine oligomers. Oligosaccharides bound by Phaseolus vulgaris erythroagglutinin were the only highly branched N‐linked residues evidenced in cats, and they were restricted to the syncytium. Unlike results reported on humans, mice and rats on lectin affinity of decidual cells, sialid acids and complex N‐linked oligosaccharides were not demonstrated in cats. Glycosylation of proteins determines many of their final properties, thus becoming essential for the embryo‐maternal dialogue during implantation and placentation. Changes in glycosylation pattern have been related to pathological pregnancies in other species. Hence, the knowledge about glycosylation profile of the normal cat placenta may lead to a better understanding of both normal and pathological reproductive events. 相似文献