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周小舟教授认为肝癌的病因是内因正气亏虚和外因外染疫毒相互作用所致,其主要病机是气虚血瘀,针对主要病机设立芪术抗癌方辨证加减治疗,临床疗效显著;周教授通过实验及临床研究亦初步阐明了芪术抗癌方的作用机制,值得临床借鉴。  相似文献   
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Open carbon nanotubes were filled with molten silver nitrate by capillary forces. Only those tubes with inner diameters of 4 nanometers or more were filled, suggesting a capillarity size dependence as a result of the lowering of the nanotube-salt interface energy with increasing curvature of the nanotube walls. Nanotube cavities should also be less chemically reactive than graphite and may serve as nanosize test tubes. This property has been illustrated by monitoring the decomposition of silver nitrate within nanotubes in situ in an electron microscope, which produced chains of silver nanobeads separated by high-pressure gas pockets.  相似文献   
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为比较不同热处理条件对水牛乳稳定性的影响,实验采用不同条件热处理后的pH缓冲容量、总溶解固体(total dissolved solids,TDS)、蛋白沉淀量及表观黏度等指标研究杂交高代水牛乳样品。结果表明:与未经处理的水牛乳样品相比,水牛乳经不同条件热处理后,其pH缓冲容量、TDS、蛋白沉淀量及表观黏度皆发生显著变化。其中水牛乳分别在经121℃/15 min和95℃/5 min处理后,其pH缓冲容量、TDS、蛋白沉淀量及表观黏度分别达到最大值和最小值。因此,认为在本实验研究范围内,水牛乳经121℃/15 min及95℃/5 min处理后,对其稳定性影响最大。  相似文献   
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Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of chemical inhomogeneity that is too severe in the model, perhaps owing to inaccurate modeling of gravitational settling or to neglected macroscopic motion that may be present in the sun. Accurate knowledge of the sun's structure enables inferences to be made about the physics that controls the sun; for example, through the opacity, the equation of state, or wave motion. Those inferences can then be used elsewhere in astrophysics.  相似文献   
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高寒草甸草地水、土、草中氮硫含量冷暖季节的变化   总被引:3,自引:0,他引:3  
根据青海高原特殊的气候分布特征,把高寒草甸草地绵羊放牧地划分为冷季和暖季。通过测定冷暖绵羊放牧地水、土壤、牧草中氮和硫含量的结果表明:水、土壤、牧草中氮和硫的含量暖季>冷季(P<0.05),其中地表水冷季含硫量分别为3.7mg/kg、5.1mg/kg,水中没有检测到氮;牧草中硫含量冷暖季分别为2952mg/kg,3262mg/kg,差异显著(P<0.05);牧草中氮含量冷暖季分别为0.62%、1.36%,差异显著(P<0.05);土壤氮含量冷暖季分别为0.22%、0.285%,差异显著(P<0.05);硫含量冷暖季分别为0.24%、0.37%。  相似文献   
18.
Interspecies somatic cell nuclear transfer (interspecies SCNT) has been explored in many domestic and non‐domestic animal species. However, problems arise during the development of these embryos, which may be related to species‐specific differences in nuclear–cytoplasmic communication. The objectives of this study were to investigate the possibility of producing bison embryos in vitro using interspecies SCNT and assess the developmental potential of these embryos. Treatment groups consisted of cattle in vitro fertilization (IVF) and cattle SCNT as controls and wood bison SCNT, plains bison SCNT and wisent SCNT as experimental groups. Cleavage and blastocyst rates were assessed, and blastocyst quality was determined using total cell number, apoptotic incidence and relative quantification of mitochondria‐related genes NRF1, MT‐CYB and TFAM. These results indicate that embryos can be produced by interspecies SCNT in all bison species/subspecies (13.34–33.54% blastocyst rates). Although increased incidence of apoptosis was observed in bison SCNT blastocysts compared to cattle SCNT controls (10.45–12.69 vs 8.76, respectively) that corresponded with significantly lower cell numbers (80–87 cells vs >100 cells, respectively), no major differences were observed in the expression of NRF1, MT‐CYB and TFAM. This study is the first to report the production of bison embryos by interspecies SCNT. Blastocyst development in all three bison species/subspecies was greater than the rates obtained in previous studies by IVF, which supports the potential role of SCNT for in vitro embryo production in this species. Yet, further investigation of developmental competence and the factors influencing blastocyst quality and viability is required.  相似文献   
19.
选择经产、胎次相同和产奶量相近的荷斯坦奶牛40头,配对分组设计分为对照组和试验组,每组20头。对照组全程饲喂基础日粮,试验组饲喂基础日粮 瘤胃稳定性脂肪。结果:瘤胃稳定性脂肪对奶牛采食量无显著影响(P>0.05);试验组牛产奶量显著升高(P<0.05),乳脂率呈上升趋势(P>0.05),但乳蛋白率未见显著变化(P>0.05);试验组奶牛外周血白细胞总数和淋巴细胞数轻度上升(P>0.05),牛奶SCC呈下降趋势(P>0.05)。结果表明,补充瘤胃稳定性脂肪可提高产奶量,对于改善机体免疫机能有一定的作用。  相似文献   
20.
Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.  相似文献   
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