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31.
全自动生化分析仪测定血清AST同工酶 总被引:1,自引:0,他引:1
应用天冬氨酸氨基转移酶抑制剂“AMANO-3”水解样品中的线粒体型天冬氨酸氨基转移酶同工酶(m-AST),测定血清中剩余的胞浆型AST同工酶(c-AST)活性,进而与总AST活性相比较并计算出受抑制剂水解的m-AST同工酶活性.由于此方法采用蛋白水解反应破坏m-AST,因此测定方法可直接应用于生化自动分析仪.亦建立了一个适于日立7150分析仪的AST同工酶联合测定方法.其测定和计算出的m-AST同工酶批内CV为3.5%~7.9%;其结果(y)与AST同工酶电泳迁移率(x)相关.y=1.019x-0.489,r=0.996(n=30).测定了113名健康人m-AST和c-AST,其m-AST参考值范围1.64~9.64U/L,x±s=(5.641±2.013)U/L;c-AST参考值范围5.69~16.81U/L,x±s=(5.641±2.013)U/L. 相似文献
32.
榄香烯对急性血瘀模型大鼠血液流变性的影响 总被引:1,自引:0,他引:1
本文观察了榄香烯对急性血瘀模型大鼠血液流变性的影响。实验结果表明:榄香烯6.25-25mg/kg/d,ip×7d,可使血瘀模型鼠的高低切变率全血粘度和还原粘度、血浆粘度、血沉、红细胞聚集指数、纤维蛋白原及红细胞电泳时间等显著降低(P<0.05、P<0.01)。提示榄香烯有活血化瘀作用 相似文献
33.
Regulation of cellulase synthesis in mycelial fungi: Participation of ATP and cyclic AMP 总被引:1,自引:0,他引:1
Summary ATP and cAMP in 4 strains of mycelial fungi were determined by luciferin-luciferase system and HPLC respectively. Cellulase synthesis was subject to the dual control of ATP and cAMP. No matter what carbon sourse was used, cellulase synthesis was repressed if intracellular ATP concentration was over 10-7mg/ml. Exogenous cAMP could increase cellulase synthesis under depression conditions. 相似文献
34.
Genetic Analysis of Parasitism in the Soybean Cyst Nematode Heterodera Glycines 总被引:2,自引:0,他引:2 下载免费PDF全文
A genetic analysis of parasitic ability in the soybean cyst nematode Heterodera glycines was performed. To identify and characterize genes involved in parasitism, we developed three highly inbred H. glycines lines, OP20, OP25 and OP50, for use as parents for controlled crosses. Through these crosses, we have identified genes in the inbred parents that control reproduction of the nematode on hosts that carry resistance genes. These genes, designated as ror-* for reproduction on a resistant host, segregate in a normal Mendelian fashion as independent loci. Host range tests of F(1) generation progeny indicated that at least one parasitism gene in both the OP20 and OP50 lines for host PI 88788 was dominant. Parasitism genes in OP50 for hosts ``Peking' and PI 90763 are recessive. Two types of single female descent populations, a single backcrossed BC(1)F(2)-derived and a double backcrossed BC(2)F(1)-derived, were established on the susceptible soybean cultivar ``Lee 68.' Host range tests for parasitism in these lines demonstrated the presence of two independent genes in OP50, one for host PI 88788 designated ror-1 and one for host PI 90763 designated ror-2. OP20 carries two independent genes for parasitism on PI 88788, designated as alleles kr3 and kr4. 相似文献
35.
The soybean cyst nematode, Heterodera glycines, is one of the most economically important pathogens of soybean. Effective management of the nematode is often dependent on the planting of resistant soybean cultivars. During the past 40 years, more than 60 soybean genotypes and plant introductions (PI) have been reported as resistant to H. glycines. About 130 modern soybean cultivars registered in the United States are resistant to certain races of H. glycines. Several resistance genes have been identified and genetically mapped; however, resistance levels in many soybean cultivars are not durable. Some older cultivars are no longer resistant to certain H. glycines populations in many production areas, especially if a soybean monoculture has been practiced. Past soybean registration reports show that all resistant cultivars developed in public institutions from the mid-1960s to the present have been derived from five PIs. This narrow genetic background is fragile. To further complicate the issue, soybean-H. glycines genetic interactions are complex and poorly understood. Studies to identify soybean resistance genes sometimes have overlapped, and the same genes may have been reported several times and designated by different names. Nevertheless, many potential resistance genes in existing germplasm resources have not yet been characterized. Clearly, it is necessary to identify new resistance genes, develop more precise selection methods, and integrate these resistance genes into new cultivars. Rational deployment of resistant cultivars is critical to future sustained soybean production. 相似文献
36.
周荣华 《中国科学:生命科学英文版》1997,40(6):657-664
Using genomicin-situ hybridization (GISH) technique, 7 translocation-addition lines, 6 translocation and translocation-addition lines, 2 ditelosomic
addition lines and 1 translocation line were identified fromTriticum aestivum L. -Psathyrostachys juncea (Fisch.) Nevski intergeneric hybrids, of which translocation-addition and translocation and translocation-addition lines
were not found in other reports. No substitutions and disornic additions were detected in the, hybrids and breakages occurred
in allP. juncea chromosomes studied. Results have shown that the improved GISH technique is a rapid and economical method for use in this
field. 相似文献
37.
Cell-free extracts of crotonate-grown cells of the syntrophic butyrate-oxidizing bacteriumSyntrophospora bryantii contained high hydrogenase activities (8.5–75.8 µmol · min–1 mg–1 protein) and relatively low formate dehydrogenase activities (0.04–0.07 µmol · min–1 mg–1 protein). The K
M
value and threshold value of the hydrogenase for H2 were 0.21 mM and 18 µM, respectively, whereas the K
M
value and threshold value of the formate dehydrogenase for formate were 0.22 mM and 10 µM, respectively. Hydrogenase, butyryl-CoA dehydrogenase and 3-OH-butyryl-CoA dehydrogenase were detected in the cytoplasmic fraction. Formate dehydrogenase and CO2 reductase were membrane-bound, likely located at the outer aspect of the cytoplasmic membrane. Results suggest that during syntrophic butyrate oxidation H2 is formed intracellularly while formate is formed at the outside of the cell. 相似文献
38.
39.
本文报道连香树木材解剖和扫描电镜研究结果,连香树木材特征较为原始,具导管和管胞,导管端壁斜、梯状穿孔板、具有超出穿孔板的三生螺旋加厚,管胞为原始的梯纹管胞,木纤维壁上具裂隙状纹孔,木薄壁组织离管型,星散状分布,木射线异型。 相似文献
40.