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1.
名贵月季品种微繁及工艺研究 总被引:3,自引:0,他引:3
研究以名贵月季品种“落霞”、“墨红”、“和平”、“金背大红”等为试材,以MS基本培养基附加不同浓度的6-BA、NAA,以诱导腋芽增殖为微繁途径。结果表明:无菌外植体的建立培养基为MS+6-BAO.5-2+NAAO.05-0.1+Vc100;芽增殖培养基为MS十BA1+NAA0.05,在此培养基上繁殖系数为5.5;生根培养基为MS+IAA1+IBA1+NAA0.1-肌醇,生根率在95%左右。生根苗移栽成活率在85%左右。同时对繁殖工艺流程、成本、商品苗产率等问题进行了讨论,给出在繁殖系数为F、生根数为b时,有效繁殖系数f=F—b,试管苗实际增殖倍数Nn=(F—b)(n-1)·F、生根苗数R1-n=f-1;当生根率为r1,移栽成活率为r2,则商品苗产率为C=r1·r2·Rn=r1·r2·b(f-1)/(f-1) 相似文献
2.
A new procedure for the analyses of tryptophan and the total amino acid composition of proteins was based on the observations that pyridine borane reduces tryptophan in trifluoroacetic acid, while other amino acids remain intact [M. Kurata, Y. Kikugawa, T. Kuwae, I. Koyama, and T. Takagi (1980) Chem. Pharm. Bull. 28, 2274-2275; W.S.D. Wong, D.T. Osuga, and R.E. Feeney (1984) Anal. Biochem. 139, 58-67]. Concentrated HCl was used instead of trifluoroacetic acid for analytical purposes. The products were stable to hydrolysis in 6 N HCl, and the reduction did not interfere with hydrolysis and subsequent analyses. Quantitative recovery was achieved with most proteins when they were subjected to acid reduction in ice-cooled concentrated HCl with two incremental additions of pyridine borane. The reaction was terminated after 10 min by dilution with an equal volume of H2O, vacuum sealing, and hydrolyzing at 110 degrees C for 22 h. The yields of the expected values for cytochrome c, catalase, bovine serum albumin, subtilisin BPN', trypsin, chymotrypsin, beta-lactoglobulin, lysozyme, and pepsin were obtained. Ovotransferrin and ovalbumin, however, yielded values for tryptophan lower than literature values. With two different ion-exchange methods, the recoveries of all other amino acids were comparable to those obtained by acid hydrolysis with 6 N HCl. Since the same hydrolysate can be analyzed for both tryptophan and all the other amino acids, the procedure is a more convenient method than those requiring separate determinations. Initial results indicate that the method may be applied to high-performance liquid chromatographic procedures with adaptations of the protocols if necessary. 相似文献
3.
Chromium in biological systems, I. Some observations on glucose tolerance factor in yeast 总被引:2,自引:0,他引:2
Glucose tolerance factor (GTF) has been isolated from a commercially available yeast extract powder, by a simple procedure under mild conditions. This cationic yellow material enhances considerably CO2 production in several yeast strains, after a lag time which can be eliminated by preincubation with glucose. The enhancement of CO2 production by GTF is not specific for glucose, and its effect on galactose raises the possibility that it influences the transport of the sugar to the cells. The ineffectiveness of GTF on cell free extract and the results of a Michaelis plot for CO2 production support this hypothesis. 相似文献
4.
Russell Timkovich 《Journal of inorganic biochemistry》1981,14(3):245-252
Reaction rates were measured for the low pH-induced Cu ligand modification of azurins from Pseudomonas aeruginosa and Alcaligenes faecalis. Loss of the intense absorption band at 625 nm obeyed a rate law: where Az is the concentration of azurin in its native oxidized form possessing the 625 nm band. For Pseudomonas aeruginosa at 25°C, n = 1 and k = 4.0 × 10-2 sec-1 M-1 in citrate buffer but 1.2 × 10-2 sec-1 M-1 in phosphate buffer. For Alcaligenes faecalis, n = 3 and k = 1.5 × 104 sec-1 M-3 in citrate and 2.6 × 103 sec-1 M-3 in phosphate. In equilibrium experiments on Alcaligenes faecalis azurin in citrate buffer, the pH-dependent change to the low pH form exhibited an apparent transition pK of 3.1. The form of the rate law implies a mechanistic scheme that contains fast equilibrium protonation steps prior to a rate limiting ligand rearrangement. 相似文献
5.
The specificity of T cells for syngeneic target cells is directed to both antigens and products of the major histocompatibility complex (MHC) on the target cell surface. This dual requirement is best accounted for by the altered-self hypothesis, which implies that the MHC products on a cell's surface are able to form complexes with many other proteins on the surface of the same cell. To account for the ability of MHC products to bind so many different cell surface antigens we propose that interactions in general among macromolecules on the surface of a membrane may be dramatically enhanced by a purely physical effect. This effect derives from the confinement of membrane macromolecules to an effective volume which is the product of membrane surface area times d, the distance over which the center of mass of the molecules can move in a vertical direction (perpendicular to the membrane surface). Because d is very small the effective concentrations of surface molecules are extremely high and their interactions are correspondingly enhanced. 相似文献
6.
由于标记缺失、生产记录不详、亲权关系不明及部分个体来源不清等历史问题,中国小熊猫圈养种群存在谱系错漏、近亲繁殖等风险。近年来,随着小熊猫种群规模不断扩大,管理者们对谱系的准确性提出了更高的需求,亲子鉴定工作也成为了研究的重点。本文采用26个微卫星标记,对国内3个小熊猫圈养种群进行了亲缘关系运算,完成了相关谱系的查错与整理。26个位点多态性与稳定性良好,联合非亲排除概率达到0.9999以上,可解决国内小熊猫圈养种群的各类亲子鉴定需求。在单亲未知或双亲未知的情况下,8或11个位点组合可实现亲子鉴定。5个位点组合可进行个体识别。在小熊猫圈养管理过程中,应用一套亲子鉴定体系对小熊猫圈养的谱系进行查漏补缺,有利于制定科学的配对计划、避免近亲繁殖,对小熊猫种群保护有着重要意义。 相似文献
7.
《L'Anthropologie》2021,125(1):102836
In this paper, I contend that children had a unique position in prehistoric social systems, functioning as primary assimilators of new technologies. Their role is especially crucial at significant turning points in history, due to a number of childhood-cognitive mechanisms that are activated in learning and playing while engaging in innovative activity. I suggest that these mechanisms developed as part of an evolutionary process that has enabled humans to better adapt to change and prosper. This line of thinking is demonstrated through a synthesis of evolutionary, cognitive-psychological models and a case study from the archaeological record of the Levantine late Lower Paleolithic. In this time, humans developed a set of creative innovations which had to be learned and assimilated, such as the innovative production of blades. I argue that these cultural changes were successfully assimilated by groups inhabiting the Levant due to the enhancement of well-established learning mechanisms, in which children played a significant role. This role might have given them a unique status in their group – as preserving old traditions practiced by their ancestors but also as active agents, part of a collective group effort of tackling present and future challenges. 相似文献
8.
《L'Anthropologie》2021,125(5):102967
Since the discovery of the first Paleolithic site in Hokkaido, we consider that the time in the half more than centuries already passed, and float today. However, our research is still a way. By today, we have not discovered the trace about a Pithecantropines (Homo erectus) and a Paleanthropic man (Homo sapiens neanderthalensis) at all in this region. We know that a Neanthropic man (Homo sapiens sapiens) dominated all the continents except Antarctica in the final time of the Pleistocene era. And they passed along the dried shoal which appeared to the north in the same time from the Asian Continent to the Island of Hokkaido, and reached it to this place. The first attainment time is an age which exceeds 20,000-years before a little from the present. We are not checking a fact which exceeds it you to be much. However, the habitants of these beginnings left the trace of the activity of them in large numbers, so that he was wonderful to inside of this island. The studies-of-prehistory research in Hokkaido has little proof of the natural science field concerned on age determination or chronology. This has serious restriction. However, the tephra-chronology of volcanic ashes has played the big role uniquely. The eruption of the Eniwa volcano of the Hokkaido central part is especially a very important index. This volcano blows off ash fall (En-a) in large quantities, and covered all large ranges. This deposited volcanic-ashes layer plays a big role to discernment of an old industry and a recent industry on the cultural chronology. The obsidian from this island and nearby hard shale was used for many industries of this Upper Paleolithic cultures as main materials. Although obsidians in the island where the different four outcrops are known well. This rock was mined in large quantities, and was carried in various places. As well as many examples in the world, we divided this rock, and the human beings of the prehistoric age were demanded for it, and it was often utilized. In it, especially the outcrop of Shirataki was located in the northern part of Hokkaido, and was very important. Large quantities of obsidian from Shirataki outcrop is discovered in a large number of Paleolithic sites within a segment 700 km in diameter at least. It covered the territory in Hokkaido and circulated further also except this island. This fact circulated as important trade materials on stone-tool fabrication among the human-beings groups from whom this island's every place differed. In this time, human beings’ activity in Hokkaido is a clear proof, which was not isolated at all. As for the studies of the prehistorians of Hokkaido distinguish, the exception put the technical process of eight different microblade productions. The technical process of some of them was limited only to the specific narrow area. Or it is proved that other technical processes are widely connected with the human-beings group of the Asian Continent on the contrary. At present, our research grasps the whole second-half Paleolithic culture, and has not yet established the year system edited by locally complete. The oldest industry of this area composed the typical stone tool of second-half Paleolithic culture from the beginning, and was accompanied by the manufacturing technique of a braid and microblade. The feature is the example in which the ruins of Kashiwadai-I were most excellent. These ruins correspond at time older than deposition of the Eniwa volcano tephra. It is located at the chill time in the second half of a Würm glacial period. The second continuing step is an industry of succession newer than this volcano tephra. It is raised as an example with Ôsatsu-16 typical ruins etc. The third phase is an industry of the end term of second-half Paleolithic culture. It is simultaneously located in the dawn of Jōmon culture. The feature of this cultural aspect is a transitional cultural stage which earthenware appears and is called what is called “Sub-Neolithic-Culture”. We can check having passed expansively, while the aspect of this last continues within a short period of time relatively. 相似文献
9.
The fascination of Antarctic scientists with Antarctic krill and their capabilities has a long and varied history, and prompted many scientists to maintain and manipulate krill under laboratory conditions. Starting in the Discovery era with Mackintosh at the King Edward Point labs on South Georgia, 1930, scientists have collected krill from sailing vessels, small boats, inflatable zodiacs and large ice-breaking vessels. Krill have been maintained in small and large jars, deep rectangular tanks, large round tanks and in flow-through and recycling systems. They have been maintained both on board research vessels and in laboratories, in flowing seawater systems at ambient conditions and in temperature-controlled environmental rooms. A few researchers have transported living krill back to their home laboratories, for example tropical laboratories in Japan (Murano) and Australia (Ikeda), temperate laboratories (Nicol) in Australia, a northern European laboratory in Germany (Marschall) and a sunny maritime laboratory in California (Ross and Quetin). The goals have been varied: short-term experiments to understand in situ physiological rates, long-term experiments to test the effects of manipulations or controlled changes in environmental conditions, and behavioral responses. We take you on a brief historical tour as we trace the lineage of modern day research on living Antarctic krill. 相似文献
10.
The in‐depth analysis of complex proteome samples requires fractionation of the sample into subsamples prior to LC‐MS/MS in shotgun proteomics experiments. We have established a 3D workflow for shotgun proteomics that relies on protein separation by 1D PAGE, gel fractionation, trypsin digestion, and peptide separation by in‐gel IEF, prior to RP‐HPLC‐MS/MS. Our results show that applying peptide IEF can significantly increase the number of proteins identified from PAGE subfractionation. This method delivers deeper proteome coverage and provides a large degree of flexibility in experimentally approaching highly complex mixtures by still relying on protein separation according to molecular weight in the first dimension. 相似文献