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排序方式: 共有146条查询结果,搜索用时 0 毫秒
91.
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93.
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aterina Vackova Darko Bosnakovski Bodil Bjrndal Penka Yonkova Natalia Grigorova Zhenya Ivanova Georgi Penchev Galina Simeonova Lyuba Miteva Anelya Milanova Tatyana Vachkova Spaska Stanilova Ivan Penchev Georgiev 《Journal of animal physiology and animal nutrition》2019,103(3):925-934
Adipose‐derived stem cells (ADSCs) possess multipotent properties, and their proper functionality is essential for further development of metabolic disorders. In the current study, we explored the impact of two n‐3 LC‐PUFAs (long‐chain polyunsaturated fatty acids, DHA—docosahexaenoic; C22:6, and EPA—eicosapentaenoic; C20:5) on a specific profile of lipolytic‐related gene expressions in the in vitro‐differentiated subcutaneous and visceral ADSCs from rabbits. The subcutaneous and visceral ADSCs were obtained from 28‐day‐old New Zealand rabbits. The primary cells were cultured up to passage 4 and were induced for adipogenic differentiation. Thereafter, the differentiated cells were treated with 100 µg EPA or DHA for 48 hr. The total mRNA was isolated and target genes expression evaluated by real‐time RCR. The results demonstrated that treatment of rabbit ADSCs with n‐3 PUFAs significantly enhanced mRNA expression of Perilipin A, while the upregulation of leptin and Rab18 genes was seen mainly in ADSCs from visceral adipose tissue. Moreover, the EPA significantly enhanced PEDF (Pigment Derived Epithelium Factor) mRNA expression only in visceral cells. Collectively, the results suggest activation of an additional lipolysis pathway most evident in visceral cells. The data obtained in our study indicate that in vitro EPA up‐regulates the mRNA expression of the studied lipolysis‐associated genes stronger than DHA mainly in visceral rabbit ADSCs. 相似文献
94.
Rubio Ivette Castillo Epigmenio Soto Rodolfo Alarcón Fernando Murcia Clara Galina Carlos S. 《Tropical animal health and production》2010,42(3):539-545
The aim was to study postpartum follicular population dynamics in Brahman cows in the Mexican humid tropics and under different
stocking rates. Lactating adult cows (n = 104) grazed native grammas (Paspalum spp., Axonopus spp.) under two stocking rates: 2.8 (high) or 1.7 (low) cows/ha. Follicle numbers and their size (millimetres) were measured
by ovarian ultrasound scanning. Animals detected in oestrus and inseminated were taken out of the study. Both stocking rates
produced similar (P < 0.05) body condition scores (BCS) and follicular dynamics. The percent of follicles, averaged over stocking rates, of <4 mm
diminished and those of 5–8 mm increased with time, whilst those of >9 mm remained constant; respective values for the previously
mentioned sizes were 60 days postpartum (n = 101), 49%, 56% and 5%; 120 days (n = 70), 28%, 66% and 6%; and 180 days (n = 15), 9%, 79% and 12%. There was a positive correlation between BCS and follicle number for size <4 mm (r = 0.73, P < 0.01), whilst for size 5–8 mm, this was negative (r = −0.51, P < 0.05), for follicles >9 mm, no difference was found (r = −0.08, P > 0.05). It was concluded that stocking rate did not affect follicular population dynamics of Brahman cows, but BCS dictated
the number and categories of follicles present regardless of the stocking rate utilised. 相似文献
95.
Radostin Simeonov Galina Simeonova 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):96-98
Background: Most reports of canine basal cell carcinomas (BCCs) focus on morphologic appearance rather than biologic behavior. Rare recurrences and no metastases have been reported in dogs. Quantitative nuclear morphometry may be useful in predicting tumor recurrence. Objective: The aim of the present study was to compare quantitative nuclear parameters of canine BCCs that did not recur within 60 weeks of excision with those that recurred. Methods: Cytologic specimens obtained from spontaneous BCCs from 11 dogs were analyzed by computerized nuclear morphometry. The dogs were monitored by their owners over a period of 60 weeks to detect local recurrence of the tumor; recurrent tumors were confirmed histologically. For each initial tumor specimen, nuclei of at least 100 neoplastic cells were measured by 2 independent observers, and mean nuclear area (MNA), mean nuclear perimeter (MNP), and mean nuclear diameter (MND) were calculated. Results: Six nonrecurrent and 5 recurrent tumors were analyzed. Neoplastic cells from BCCs that subsequently recurred had higher MNA (102.41 ± 4.57 μm2), MNP (36.27 ± 0.61 μm), and MND (11.21 ± 0.27 μm) than cells from nonrecurrent BCCs (MNA 87.66 ± 4.79 μm2, MNP 33.51 ± 0.78 μm, MND 10.36 ± 0.29 μm) (P<.001; Mann–Whitney U‐test). Conclusion: Based on these preliminary results, nuclear morphometry may be a useful tool to predict local recurrence of BCCs in dogs. 相似文献
96.
In order to evaluate an artificial insemination programme and reproductive efficiency of dairy herds in Uruguay, a survey was conducted with five dairy farms, utilizing a total of 768 lactating Holstein cows. Precision of oestrous detection was assessed by one milk progesterone sample taken on day of breeding and was 11.1%. Two additional samples taken at day 10 and 23 were used to confirm ovulation and early pregnancy. Accuracy of pregnancy estimation by milk progesterone was 70.4%. Reproductive efficiency was determined by the analysis of records. Average intervals from calving to first service were 101 days and to conception 132 days and these were affected by parity, body weight and body condition at calving, but not at breeding, or by milk production. Oestrous detection rates and pregnancy rates were 37.5 and 15.6%, respectively. It was concluded that losses in reproductive efficiency in dairy farms of Uruguay in a seasonal artificial insemination programme were mainly due to unobserved heats, rather than incorrect oestrous detection. 相似文献
97.
Aleksandr KAVETSKIY Galina YAKUBOVA Nikolay SARGSYAN Clyde WIKLE Stephen A. PRIOR Henry Allen TORBERT Bryan A. CHIN 《土壤圈》2019,29(3):334-343
Soil carbon mapping is extremely useful in assessing the effect of land management practices on soil carbon storage. Applications of neutron-gamma analysis in scanning mode for mapping of soil carbon are discussed. A Global Positioning System(GPS) device and softwares required to simultaneously acquire gamma signals and geographical positions during scanning operations were added to an existing measurement system. The reliability of soil carbon measurements in scanning mode was demonstrated to be in agreement with results acquired from static mode. The error analysis indicated that scanning measurements can be conducted with the same accuracy as static measurements in approximately one fourth the time. To obtain results suitable for mapping analogous to traditional chemical analyses(i.e., ± 0.5 in weight percent or ± 0.5 w%), scanning time over a given site should be ca. 15 min using the current measurement system configuration. Based on this measurement time, a reasonable towing speed of 3–5 km h-1, the necessity for complete site coverage during scanning, the number of sites(within the surveyed field), and the required total measurement time can be estimated. Soil carbon measurements for 28 field sites(total area ca. 2.5 ha) were conducted in ca. 8 h. Based on acquired data,a soil carbon distribution map was constructed utilizing various softwares. The surveyed field area included an asphalt road that had carbon readings higher than the surrounding land. The clarity with which these carbon-rich zones were delineated on the constructed map represents evidence supporting the veracity of this method. Neutron-gamma analysis technology can greatly facilitate timely construction of soil carbon maps. 相似文献
98.
A mixing-cell model for estimating nitrate seepage losses from agricultural soils in winter A mixing-cell model is developed with which the leaching of nitrate from agricultural soils in temperate regions during winter can be estimated. The model assumes steady-state flow conditions and takes nitrogen mineralization in the upper soil as well as nitrate deposition from the atmosphere into consideration. Model results are compared with results from a convective-dispersive solute flow model. They show that for common field soil dispersivities mixing-cell model results compare well with those obtained from convective-dispersive theory. With the mixingcell model nitrate leaching calculations were carried out for a variety of soil and climatic conditions. They show that the combined effect of N-mineralization and N-deposition may influence the amount of leached nitrate in winter considerably, especially in regions with light soils and high seepage rates. It is shown that the model can be used to derive late fall site-specific upper limits for soil mineral nitrogen for groundwater protection purposes. Such upper limits should reflect the crop-specific rate of N-mineralization that can be expected during winter. 相似文献
99.
In a previous study, we demonstrated that Suillus granulatus exhibits positive growth responses to added litter. From this, we hypothesized that this positive growth response (increased number of EM root tips) would be accompanied by increased activities of enzymes that enable EM fungi to utilize litter as a nutrient source. We tested this hypothesis by adding sterile litter in replicate treatment/control blocks, and assaying cellulase, laccase and phosphatase activities in the dominant fungal species, S. granulatus. We used healthy, growing EM roots for both treatment and control assays. Activities of all enzymes increased significantly in response to litter addition (P < 0.05 laccase; P < 0.01 cellulase; P < 0.001 phosphatase). Hence, litter accumulation apparently causes functional as well as structural changes to the EM fungal community that would significantly affect carbon cycling in forest ecosystems. 相似文献
100.
Russia presents an interesting case of a country which has strived to implement innovation policies since the transition period but so far has achieved mixed results. This study aims to analyze the impact of knowledge production and knowledge spillovers on regional growth in Russia within a framework of endogenous growth models. Applying GMM and spatial error panel modeling techniques to Rosstat data for 80 Russian regions from 2005 to 2013, the authors test the hypothesis about the relevance of R&D and expenditure on technological innovations (H1) and the hypothesis about the relevance of knowledge spillovers (H2) on the growth rates of GRP per capita. Hypothesis 1 was confirmed while Hypothesis 2 was rejected, indicating the absorptive capacities of innovatively lagging regions were not high enough for effective adaptation of new technologies from technologically innovative regions. Inclusion of indicators related to additional channels of knowledge diffusion in regressions resulted in the relevance of FDI and imports of goods and services for regional growth. Results of the study could form the basis for developing innovation policies for the Russian regions. 相似文献