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41.
Necropsy data from a Primate Center were used in a study of the brain weight-body weight relationships of 12 species of nonhuman primates. The sample sizes ranged from six Cercopithecus aethiops to 163 Macaca mulatta. By plotting mean brain-mean body weight of each species on log-log paper, it was shown that the straight line fitting the plots of all species had a slope of 0.72. Slopes for three species of the genus Macaca, and for six species of the family Cebidae, were 0.61 and 0.81 respectively. Coefficients of determination of the three lines were greater than 0.90. Two species of the family Cebiade, Saimiri sciureus and Aotus trivirgatus, had equivalent body weights, but the former had a 30% larger brain than the latter. The results suggest that brain-body weight scaling characteristics of primate species can be studied effectively using necropsy data. Some statistically significant discrepancies between these and published data, however, show that more data are required to describe these characteristics with greater certainty.  相似文献   
42.
E E Keha  H Ronft  G B Kresze 《FEBS letters》1982,145(2):289-292
45Ca2+ incorporated in response to glucose was selectively mobilized from the beta-cell-rich pancreatic islets of ob/ob-mice after raising the intracellular Na+ by removal of K+ or addition of ouabain or veratridine. Also studies of insulin release indicated opposite effects of glucose and Na+ on the intracellular sequestration of calcium. The fact that glucose inhibits insulin release induced by raised intracellular Na+ indicates that this sugar can lower the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+] might well explain previous observations of an inhibitory component in the glucose action on the 45Ca2+ efflux.  相似文献   
43.
In brain tissue a spectrin-like calmodulin-binding protein calspectin, or fodrin, is concentrated in a synaptosome fraction, where most of the calspectin is associated with the synaptic membranes. This endogenous calspectin was phosphorylated by protein kinase system(s) associated with the membranes. Here, we report the solubilization and partial purification of the membrane-associated calspectin kinase activity. The activity was resolved on a gel filtration column into two fractions, peaks I and II having estimated Mr of 800 000 and 88 000. The activity of peak I was dependent on the presence of both Ca2+ and calmodulin. Peak II revealed a basal activity in the absence of Ca2+ and calmodulin, which was stimulated 2-fold by addition of Ca2+. Calmodulin had no effect on the peak II activity.  相似文献   
44.
Abstract: The molecular size of the benzodiazepine (BZ) receptor in the synaptic membrane of brain cortex (bovine or rat) was determined by an improved version of the radiation inactivation method to be 220,000. An identical size was found simultaneously for the associated γ-aminobutyric acid (GABA) receptor and for the component binding β-carboline esters. It is proposed that all three activities reside in a single protein or protein complex in the membrane. The size in solution, after extraction into Triton X-100 medium from exhaustively washed membranes, was estimated by sedimentation constant (9.4S) and by gel filtration (∼230,000 apparent MW), again with the BZ and GABA binding activities behaving identically. This size applies to the component that undergoes photoaffinity labelling by [3H]flunitrazepam in the membrane, and contains a 51,000 Mr polypeptide as the BZ-binding subunit. It is concluded that a protein complex or oligomer of 200,000–220,000 MW carries a class of BZ-binding sites and an associated class of GABAA sites.  相似文献   
45.
In earlier work, immature oocytes of the irradiated population RÖI4 of Drosophila melanpgaster were found to be radioresistant relative to those of the basic population RÖI and to those of the control population Berlin wild (+K). The resistance of RÖI4 relative to RÖI was previously attributed to a hypothetical “factor” rar-3. In the present paper, evidence is presented to show that rar-3 is a single, recessive genetic factor, located on chromosome 3 at a map position of about 49.8. The action of rar-3 is apparently independent of that of rar-1 and rar-2, the factors already present in RÖI.  相似文献   
46.
Condensed tannins have been isolated from legume pasture species and purified by gel chromatography on Sephadex G-50 and LH-20 media. Molecular size di  相似文献   
47.
The purification of spinach beet phenolase has been modified to include equilibration of the crude macerate with 0.5% cetyl-trimethylammonium bromide a  相似文献   
48.
Atherosclerosis is an important cause of cardiovascular disorders worldwide. Natural botanical drugs have attracted attention due to their antioxidant, anti-inflammatory, and antiatherogenic properties in the treatment of atherosclerosis. Punicalagin is the major bioactive component of pomegranate peel, and has been shown to have antioxidant, anti-inflammatory, antiviral, anti proliferation, and anticancer properties. To explore its antiatherogenic properties at a molecular level, we investigated the genome-wide expression changes that occur in differentiated THP1 cells following treatment with a non-toxic dose of punicalagin. We also conducted a molecular docking simulation study to identify the molecular targets of punicalagin.  相似文献   
49.
植物生物反应器是一种新兴的重组蛋白表达系统,是分子农业的核心内容之一。本研究在本氏烟草(Nicotiana benthamiana)中表达了抗八肽(DYKDDDDK, FLAG)标签抗体,并对其进行纯化与鉴定。通过多次免疫小鼠获得高效价抗FLAG抗体并测出其编码序列,然后亚克隆至植物DNA病毒表达载体,最后通过农杆菌介导转染烟草叶片。经Western blotting检测了转染后2−9 d抗体的表达情况:3 d后FLAG抗体开始在烟草叶片中表达,5 d后表达量达到峰值,每千克鲜叶估计可表达66 mg FLAG抗体。抗体经过分离纯化后浓缩为1 mg/mL,按1:10 000稀释仍可识别1 ng/mL的抗原,表明植物生产的FLAG抗体具有高亲和力。植物生物反应器可用于生产高亲和力抗体,并具有简易、成本低和生产周期短等特点,具有很高的应用价值。  相似文献   
50.
茄子是重要的园艺作物,也是茄科植物中种植最广泛的蔬菜之一。茄子果实相关农艺性状是一种复杂的数量性状,传统育种选育效率低、周期长。高通量测序技术与生物信息学技术的快速发展,使得全基因组关联分析(genome-wide association study, GWAS)在解析茄子果实相关复杂农艺性状的遗传规律方面展现出巨大的应用前景。本文对全基因组关联分析在茄子的果形、果色等果实相关农艺性状中的研究进展进行了综述;针对茄子数量性状遗传研究中普遍存在的“丢失遗传力”(missing heritability)问题,从4个GWAS策略在茄子果实相关农艺性状研究中的应用热点出发,提出了未来茄子GWAS的发展对策;并结合当前茄子遗传改良的实践需求,展望了GWAS策略在茄子分子育种领域的广阔应用前景。本文为今后利用GWAS解析各种茄子果实相关性状的遗传基础以及选育符合消费者需求的果实材料提供了理论依据和参考。  相似文献   
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