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901.
902.
903.
由于地球物理方法本身受分辨率和保真度的限制,其在断层和裂缝识别上的应用也就有精度和尺度上的差异。为此,可采用不同的方法技术来识别不同尺度的断层和裂缝,即在断层识别上,利用地震剖面和水平切片解释大断层,采用相干分析方法识别小断层;在裂缝识别上,主要采用多方位AVO方法识别大尺度裂缝的发育特征,采用成像测井来识别微小裂缝的特征情况。实际应用表明,上述方法在相应尺度断层和裂缝上的识别效果较好。 相似文献
904.
管道老龄化是世界性问题,进入老龄期的管道能否继续安全运行,需要从管道的原始条件、维护条件及油田的产量方面进行综合考量。美国贯穿阿拉斯加管道是老龄管道继续安全运行的成功范例,借鉴其成功经验,可以促进与保证东北原油管网的安全运行。对于东北管网庆铁线交替输送中俄原油方案,认为必须对管道的原始条件和管道的应力交变问题进行仔细调查与研究,慎重决策。 相似文献
905.
加查县优良核桃资源调查初报 总被引:1,自引:0,他引:1
针对过去对西藏核桃主产区之一加查县优良核桃单株调查不全、资料不详等问题,对加查县核桃优良单株的分布进行了较详细的调查。调查结果,共搜集到了酥油核桃等36个外观品质及口感好的品种(单株),突破了原来在《中国果树志.核桃卷》记载的11个优良单株,并详细记录了每个单株的当地名称,确定了分布的具体位置,如经纬度、海拔及所在村镇,同时取样测定了坚果的基本物理性状。 相似文献
906.
907.
Type II innate lymphoid cells (ILC2s) are widely distributed in the blood, intestines, trachea, lung, spleen, liver, animal fat and skin, and involved in the innate immune responses. ILC2s have attracted much attention for its important roles in the conversion of white adipose to beige adipose. Studies have shown that ILC2s are essential for the proliferation and differentiation of adipocyte precursor cells, and they also play a vital role in anti-parasitic infection and allergic inflammation. This review discusses the discovery, differentiation, development, distribution and function of ILC2s, and their relationships with the browning of white adipose tissue for providing valuable references on understanding the pathogenesis, prevention and treatment of obesity and fat metabolism disorders. 相似文献
908.
909.
ZHA Xing-qin XIAO Jing CHENG Wen-min HUO Jin-long WANG Shu-yan WANG Pei PAN Wei-rong ZENG Yang-zhi 《中国畜牧兽医》2017,44(1):167-172
In this study, different concentrations of glycerol were added to semen cryoprotective extenders of Banna Mini-pig inbred line (BMI), different thawing solutions and thawing methods were studied. After thawing, the motility, the rates of plasma integrity and acrosome integrity were compared to optimize the cryopreservation method of BMI semen. The results showed that the motility, the rates of plasma integrity and acrosome integrity were significantly higher in 2% and 3% glycerol groups than those in 1%, 4% and 5% glycerol groups (P<0.05);The motility, the rates of plasma integrity and acrosome integrity were significantly higher in thawing solution Ⅰ than those in thawing solution Ⅱ, Ⅲ and Ⅳ (P<0.05); Through comparing the motility, the rates of plasma integrity and acrosome integrity, the thawing effect in 40℃ 6 s and 50℃ 6 s groups were better than that in 38℃ 30 s (P<0.05). In conclusion, the optimal semen cryoprotective method for BMI was 2% or 3% glycerol as cryoprotectant, using thawing solution Ⅰ to thaw at 40℃ 6 s or 50℃ 6 s. 相似文献
910.
GUAN Zhi-hui CHEN Bao-jian PAN Tian-biao QIN Zhao-xian LIU Jia-qi MA Qing-yan NONG Su-qun XIE Bing-kun 《中国畜牧兽医》2017,44(3):628-634
The objective of this study was to clone the acyl-coenzyme A oxidase 1 (ACOX1) gene of Luchuan pig and analyze its genetic structure with bioinformatics. A pair of special primer was designed according to predicted sequence of pig ACOX1 gene in GenBank. The ACOX1 gene was amplified by RT-PCR, the physicochemical property and secondary structure of ACOX1 gene were systemically analyzed by bioinformatics techniques. The results showed that ACOX1 gene fragment included an 1 986 bp whole length CDS (coding 661 bp amino acids). The sequence multi-aligned results showed that Luchuan pig shared 99.5%, 85.5%,87.1%,66.3%,75.6%,84.0%,82.3%,81.1% and 69.1% of similar nucleotide sequence with that of pig,human, zebrafish, chicken, rhesus monkeys, mice, rat and frog, respectively. The prediction of ACOX1 secondary structure showed that Luchuan pig ACOX1 had no signal peptide and transmembrane structure. This study suggested that the whole CDS sequence of ACOX1 gene was successfully cloned in Luchuan pig, and the cloning and analysis of ACOX1 gene provided an important foundation for further studying on the fatty deposition and lipornetabolism of ACOX1 gene in Luchuan pig. 相似文献