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排序方式: 共有418条查询结果,搜索用时 31 毫秒
61.
Wypij JM Fan TM Fredrickson RL Barger AM de Lorimier LP Charney SC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(1):158-163
BACKGROUND: Feline oral squamous cell carcinoma (OSCC) may cause painful bone destruction. Given the local invasiveness and rapid clinical progression of OSCC, conventional therapies are often palliative. In human cancer patients, zoledronate exerts anticancer effects by inhibiting tumor-induced angiogenesis and malignant osteolysis. HYPOTHESIS: Zoledronate will exert in vitro and in vivo anti-angiogenic and antiresorptive effects in feline OSCC. ANIMALS: Eight cats with OSCC were prospectively treated with zoledronate and conventional treatment modalities. METHODS: In vitro, zoledronate's effects in modulating soluble vascular endothelial growth factor (VEGF) secretion and receptor activator of nuclear factor kappaB (NF-kappaB) ligand (RANKL) expression were investigated in a feline OSCC cell line (SCCF1). In vivo, basal serum C-telopeptide (CTx) concentrations were compared among normal and OSCC-bearing cats, and the biologic effects of zoledronate administration in cats with naturally occurring OSCC were quantified by serially assessing circulating serum VEGF and CTx concentrations. RESULTS: In vitro, zoledronate concentrations greater than 3 microM reduce soluble VEGF secretion in the SCCF1 cell line. The expression of RANKL in the SCCF1 cell line was also modulated by zoledronate, with low concentrations (3 microM) decreasing but higher concentrations (30 microM) increasing RANKL expression in comparison with untreated cells. In vivo, cats with bone-invasive OSCC had greater serum CTx concentrations in comparison with geriatric, healthy controls. Treatment with zoledronate rapidly decreased circulating serum VEGF and CTx concentrations in cats with spontaneously occurring OSCC. CONCLUSIONS AND CLINICAL IMPORTANCE: Zoledronate exerts in vitro and in vivo effects that may favor the slowing of tumor growth and pathologic bone turnover associated with OSCC. 相似文献
62.
Swanson KC Kelly N Salim H Wang YJ Holligan S Fan MZ McBride BW 《Journal of animal science》2008,86(4):909-915
Twenty-four yearling beef steers (initial BW = 510 +/- 4.9 kg) predominantly of Angus breeding were used in a randomized complete block design to determine the effect of dietary CP concentration on pancreatic cellularity, mass, and alpha-amylase and trypsin activities. Treatment diets were formulated to contain 8.8, 11.0, 13.2, and 15.4% CP. Soybean meal and Top Soy (ruminal bypass soybean meal) were used as supplemental protein sources to ensure that MP intake was increased with increasing dietary CP concentrations. Steers were penned in groups of 4 (1 steer per treatment) and individually fed at 2.5x the NE(m) requirement by using Calan gates for 28 d before tissue collection. Four steers (1 pen) were slaughtered per week. Pancreases were weighed, subsampled, frozen in liquid N(2), and stored at -80 degrees C until analyses for DNA, RNA, and protein concentrations, and alpha-amylase and trypsin activities. Pancreatic weight (g and g/kg of BW) did not differ among treatment groups. Pancreatic DNA concentration (mg/g) decreased linearly (P = 0.06) with increasing CP concentration. Pancreatic protein (g/pancreas) increased linearly (P = 0.08) with increasing dietary CP concentration. Pancreatic alpha-amylase activity (U/g, U/mg of DNA, U/g of protein, U/pancreas, and U/kg of BW) increased linearly (P < or = 0.04) with increasing dietary CP concentration. Pancreatic trypsin activity (U/g, U/g of DNA, U/g of protein, U/pancreas, and U/kg of BW) increased linearly (P < or = 0.09) with increasing dietary CP concentration. Pancreatic alpha-amylase and trypsin activities (U/mg of RNA) responded quadratically (P < or = 0.09), with the greatest alpha-amylase activity observed in the 13.2% CP treatment. These data indicate that increasing dietary CP concentration decreases pancreatic cell numbers and also increases the concentration and content of pancreatic alpha-amylase and trypsin activities. Changes in cell number and size may be important factors regulating digestive enzyme production in the pancreas of cattle. 相似文献
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The invasive fall armyworm Spodoptera frugiperda(J. E. Smith) invaded Asia in 2018, colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and summer. This has resulted in widespread infestations, with significant impacts on maize production in various Asian countries. Previous studies have shown that the invasion of this pest can alter the species relationships of maize pests, but the actual impact on maize pest manageme... 相似文献
66.
In order to identify gene sequences unique to the virulent strains, suppression subtractive hybridization (SSH) was conducted using virulent Streptococcus suis type 2 (SS2) strain HA9801 and avirulent S. suis type 2 strain T15. Thirty genomic regions were absent in T15, and the DNA sequences of these regions in HA9801 were determined. These DNA fragments, containing putative virulence genes, encoded 28 proteins that were homologous to proteins involved in various aspects of cellular surface structure, molecular synthesis, energy metabolism, regulation, transport systems and others of unknown function. According to the published SS2 genomic sequence of the Chinese strain 98HAH33, PCR primers for 14 significant DNA fragments were designed and used for detection of the distribution of these fragments in S. suis strains from different sources, serotypes, regions, groups and times. The results showed that these 14 DNA fragments were widely distributed in 37 detected SS2 strains, yet were absent among the avirulent strain T15. Moreover, these fragments could be detected in other serotypes of S. suis, but each serotype had a different distribution of the fragments. 相似文献
67.
By the wind turbine design, start and stop, control, operation and other aspects of analysis, and combined with the actual production,the double leg double furnace structure of 300MW CFB boiler one or two fan energy-saving plan had be selected. By compari 相似文献
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YANG Ren-Min LIU Feng ZHANG Gan-Lin ZHAO Yu-Guo LI De-Cheng YANG Jin-Ling YANG Fei YANG Fan 《土壤圈》2016,26(5):699-708
Due to the almost homogeneous topography in low relief areas, it is usually difficult to make accurate predictions of soil properties using topographic covariates. In this study, we examined how time series of field soil moisture observations can be used to estimate soil texture in an oasis agricultural area with low relief in the semi-arid region of northwest China. Time series of field-observed soil moisture variations were recorded for 132 h beginning at the end of an irrigation event during which the surface soil was saturated. Spatial correlation between two time-adjacent soil moisture conditions was used to select the factors for fuzzy c-means clustering. In each of the ten generated clusters, soil texture of the soil sample with the maximum fuzzy membership value was taken as the cluster centroid. Finally, a linearly weighted average was used to predict soil texture from the centroids. The results showed that soil moisture increased with the increase of clay and silt contents, but decreased with the increase of sand content. The spatial patterns of soil moisture changed during the entire drying phase. We assumed that these changes were mainly caused by spatial heterogeneity of soil texture. A total of 64 independent samples were used to evaluate the prediction accuracy. The root mean square error (RMSE) values of clay, silt and sand were 1.63, 2.81 and 3.71, respectively. The mean relative error (RE) values were 9.57% for clay, 3.77% for silt and 12.83% for sand. It could be concluded that the method used in this study was effective for soil texture mapping in the low-relief oasis agricultural area and could be applicable in other similar irrigation agricultural areas used in this study. 相似文献
70.
Teng BS Wang CD Yang HJ Wu JS Zhang D Zheng M Fan ZH Pan D Zhou P 《Journal of agricultural and food chemistry》2011,59(12):6492-6500
Inhibition of protein tyrosine phosphatase 1B (PTP1B) activity has been considered to be a promising therapy approach to treat type 2 diabetes. In this work, a novel PTP1B activity inhibitor, named FYGL (Fudan-Yueyang-G. lucidum), was screened from the fruiting bodies of Ganoderma lucidum and showed an efficient PTP1B inhibitory potency with IC?? = 5.12 ± 0.05 μg/mL. FYGL is a water-soluble macromolecular proteoglycan with a protein to polysaccharide ratio of 17:77 and a viscosity-average molecular weight (M(η)) of 2.6 × 10?. The type 2 diabetic mice treated orally by FYGL showed an obvious decrease in plasma glucose level compared with the diabetic controls without drug treatment, comparable with that of diabetic mice treated with metformin, a clinical drug. The toxicity of FYGL is very low. The results indicate that FYGL may serve as a drug candidate or a health-care food for diabetic therapy or protection. 相似文献