检索结果-内蒙古大学图书馆

PURIfICATION Of fLUORESCEIN AND fLUORESCEIN DERIVATIVES BY CELLULOSE ION EXCHANGE CHROMATOGRAPHY

IMMUNOCHEMISTRY 1967年第4期4卷 191-+页

作者： DANDLIKER, WB ALONSO, R Division of Biochemistry Scripps Clinic and Research Foundation La Jolla California USA

A method for the purification of ionic dyes by cellulose ion exchangers is presented. The underlying rationale is based upon approximate knowledge of the pK''s of the ionizing groups of the dye. fluorescein purified by DEAE cellulose chromatography has a molar extinction coefficient of 8.72 x 104 in 0.01 [image] NaOH at 491 m[mu]. This agrees with results obtained by other workers using different methods of purification. fluorescein amine is readily purified on a 10 g scale by a similar method and an improved procedure for converting the amine to the isothiocyanate is given. The amine is a convenient and stable compound which can be standardized, stored and converted to the isothiocyanate as needed for fluorescent labeling.

关键词： f fluorescein fNO 2 nitrofluorescein fNH 2 fluorescein amine fNCS fluorescein isothiocyanate DEAE diethylaminoethyl AcOH acetic acid NH 4 OAc ammonium acetate

来源：评论

学校读者我要写书评

暂无评论

MULTIPLE MOLECULAR fORMS Of XANTHINE DEHYDROGENASE AND RELATED ENZYMES .2. CONVERSION Of ONE fORM Of XANTHINE DEHYDROGENASE TO ANOTHER BY EXTRACTS Of DROSOPHILA MELANOGASTER

引用

BIOCHIMICA ET BIOPHYSICA ACTA 1968年第2期160卷 178-&页

作者： SHINODA, T GLASSMAN, E Department of Biochemistry and The Genetics Curriculum The University of North Carolina Chapel Hill N.C. U.S.A.

1. 1. Xanthine dehydrogenase of Drosophila melanogaster exists predominantly as one form, XDH-I, in fresh homogenates. However, a second form, XDH-II, is found in partially purified extracts. The two forms of xanthine dehydrogenase are separable on DEAE-cellulose columns and by polyacrylamide gel electrophoresis indicating that each has a different charge. XDH-I sediments slightly faster than XDH-II during sucrose gradient centrifugation indicating a small difference in molecular weight or in conformation. Other properties of the molecules are not too different. 2. 2. XDH-I can be converted to a form like XDH-II by incubation with appropriate Drosophila extracts. Preliminary analysis indicates that the converter molecule has the properties of a large protein. 3. 3. The properties of XDH-II mimic the properties of xanthine dehydrogenase from flies grown on a high protein diet. These flies also have 3- to 5-fold levels of xanthine dehydrogenase activity but no increase in xanthine dehydrogenase antigenicity (cross-reacting material against xanthine dehydrogenase antibody). It is tempting to speculate that the conversion of XDH-I to XDH-II studied in this paper represents an process in vitro related to the regulation in vivo of xanthine dehydrogenase in Drosophila.

关键词： XDH-I one form of xanthine dehydrogenase XDH-II another form of xanthine dehydrogenase OR the Oregon-R wild type strain of D. melanogaster PAC the Pacific wild type strain of D. melanogaster Pm a strain of D. melanogaster containing Pm Sb/Xa ma − l a strain containing v f Bx 3 ma − l ry a strain containing st ry

来源：评论

学校读者我要写书评

暂无评论

BETA-GALACTOSIDASE INDUCTION IN CELLS Of ESCHERICHIA COLI NOT UTILIZING GLUCOSE

引用

BIOCHIMICA ET BIOPHYSICA ACTA 1967年第1期134卷 188-+页

作者： GERSHANOVITCH, VN BOURD, GI JUROVITZKAYA, NV SKAVRONS.AG KLYUTCHOVA, VV SHABOLENKO, VP Laboratory of Biochemical Genetics of Bacteria The Gamaleya Institute for Epidemiology and Microbiology Academy of Medical Sciences Moscow U.S.S.R. Laboratory of Bacterial Genetics The Gamaleya Institute for Epidemiology and Microbiology Academy of Medical Sciences Moscow U.S.S.R.

来源：评论

学校读者我要写书评

暂无评论

A STUDY Of NUCLEAR ISOMERS WHICH DECAY BY SPONTANEOUS fISSION

引用

NUCLEAR PHYSICS 1966年第2期89卷 267-+页

作者： BRENNER, DS WESTGAARD, L BJORNHOLM, S The Niels Bohr Institute University of Copenhagen Denmark

Data are presented for the pulse-height distribution of fission fragments which results from the spontaneous fission decay of the 14 ms 242 Am isomer, indicating a normal asymmetric yield-mass distribution for the fragments. The partial cross section for production of the isomer by 12 MeV deuteron bombardment of 242 Pu and the spontaneous fission half-life are determined to be 8±3 μ b and 16.7±1.5 ms, respectively. A search was made for isomers which decay by spontaneous fission produced in deuteron bombardments of 232 Th, 235 U, 238 U, 239 Pu, 241 Am and 243 Am and proton bombardment of 243 Am. Upper limits are established for spontaneous fission decay with half-lives in the ranges 10–20 μ s to 1 h. A comparison is made between experimental data from deuteron bombardments of 242 Pu and the results of calculations based on the compound-statistical model.

关键词： NUCLEAR REACTIONS 242 Pu(d, 2n), (d, f), E = 12 MeV measured σ f (delayed)/ σ f (prompt). Enriched target 232 Th, 235 U, 239 Pu, 241 Am, 243 Am(d, x n)(d, f), E = 12 MeV 243 Am(p, x n)(p, f), E = 13 MeV measured upper limits σ f (delayed)/ σ f (prompt). Enriched targets RADIOACTIVITY 242 Am isomer [from 242 Pu(d, 2n)] measured T ½ (sf), E fragment -spectrum. Enriched target

来源：评论

学校读者我要写书评

暂无评论

A history of the Centralia School District

A history of the Centralia School District

引用

作者： Schultz, Clara Chapman University

学位级别：M.A.

The purpose of this program of research was to compile a history of the Centralia School District from 1875 to 1964. The importance of this written history was emphasized as statistics were investigated, and individual recollections were corroborated. Personal educational experiences in the Centralia School District prior to 1895 had become increasingly more difficult to substantiate due to the advanced ages of the participants, and, had this research been post-poned indefinitely, many sources of direct information would have been lost forever. This history is also an important factor in preserving District identity, because in the near future Centralia will be compelled by law to become part of a larger unified school district. This work has been organized into six chapters and an appendix. Chapter one reviews the educational trends in California which eventually influenced the education offered in the first Centralia school. The second chapter considers the fourteen years which Centralia spent as part of Los Angeles County. The third chapter traces the district's development from 1889 when it became Orange County, to 1947 when Glen Dysinger was employed. Chapter four continues the growth of the Centralia School District from 1947 to 1961 during Dysinger's years of leadership as teaching principal and Superintendent. The fifth chapter recounts the district's growth under Palmer Campen's influence, first as Business Manager and later as the second Superintendent. Chapter six states that the district has three new top administrators in September of 1964, and that the district was planning toward compulsory unification. Appendix A contains selected influential philosophies of education, and selected excerpts from biennial reports designed to illustrate the type of education offered to the children of the Centralia School District several decades before the turn of the century. Appendix B consists of tables and charts composed of selected statistics, exempli gratia, av

关键词： S o c i a l s c i e n c e s , E d u c a t i o n , C a l i f o r n i a

来源：评论

学校读者我要写书评

暂无评论

Participation of anhydroleucovorin in the hydroxymethyl tetrahydrofolic dehydrogenase system

引用

BBA - Biochimica et Biophysica Acta 1957年第3期26.0卷 646-647页

作者： Osborn, M.J. Huennekens, f.M. Department of Biochemistry University of Washington Seattle WA United States

来源：评论

学校读者我要写书评

暂无评论

PRECISION HALf-LIfE MEASUREMENTS Of 14 POSITION-EMITTING NUCLEI

引用

NUCLEAR PHYSICS 1965年第3期61卷 479-&页

作者： EBREY, TG GRAY, PR Phillips Petroleum Company Bartlesville Oklahoma USA

Precision half-lives have been measured for fourteen positon-emitting nucleides. The weighted average half-lives are N 13 , 9.96±0.02 min; f 18 109.87±0.12 min; P 3c , 2.49±0.01 min; Cl 34m , 31.99±0.05 min; K 38 , 7.70±0.02 min; fe 53 , 8.51±0.02 min; Ni 57 , 35.99±0.12 h; Cu 62 , 9.76±0.02 min; Ga 68 , 68.33±0.09 min; Mo 91 , 15.49±0.01 min; Ag 106 , 23.96±0.04 min; Ag 108 , 2.41±0.02 min; Sb 120 , 15.89±0.04 min; and Pr 140 , 3.39±0.01 min.

关键词： RADIOACTIVITY N 13 f 18 P 30 Cl 34 K 38 fe 53 Ni 57 Cu 62 Ga 68 Mo 91 Ag 106 Ag 108 Sb 120 Pr 140 [from (Z A+1) (n 2n) except N 13 Ag 108 ] measured T 1 2 natural targets except K 39 Cu 63 ∣

来源：评论

学校读者我要写书评

暂无评论

fIBROUS STRUCTURES WITHIN MATRIX Of DEVELOPING CHICK EMBRYO MITOCHONDRIA

引用

EXPERIMENTAL CELL RESEARCH 1962年第2期26卷 424-+页

作者： NASS, MMK NASS, S The Wenner-Gren Institute for Experimental Biology University of Stockholm Sweden

An electron microscopical investigation of mitochondria from many regions of chick embryos from unincubated blastoderm through head process stages has revealed the presence of a characteristic fibrous material within the mitochondria. Various fixation techniques and electron "strains" were used, and thus far alkalinized lead acetate and uranyl acetate were particularly effective in increasing the contrast of this material. The fibers are more diffuse in stages prior to the primitive streak stage, when they become dense rods of 50-100 A diameter with some fibers extending towards the periphery of the mitochondrion from the central core. The fibrous material is characteristically observed within an area of the mitochondrial matrix which is very electron lucid. from a survey of the literature and the staining properties thus far studied it is suggested that the material may be related to deoxyribonucleic acid.

关键词： M mitochondrion f mitochondrial rods and fibers V large vesicular body containing some electron-dense material

来源：评论

学校读者我要写书评

暂无评论

The organization of pallidosubthalamic fibers in the monkey

引用

Brain Research 1968年第3期11卷 522-559页

作者： Carpenter, Malcolm B. fraser, Richard A.R. Shriver, Joyce E. Department of Anatomy College of Physicians and Surgeons Columbia University New York NY United States

A study was made to determine the topographical organization of pallido-subthalamic fibers in the rhesus monkey. Streotaxic lesions were produced in: (1) the lateral pallidal segment (12 lesions in 10 animals), (2) the medial pallidal segment (6 lesions in 6 animals), and (3) both pallidal segments (4 lesions in 4 animals). Degeneration resulting from these lesions was studied in transverse, horizontal and sagittal sections stained by the Nauta and Gygax technic¹⁴. The following conclusions were drawn from this study: 1. 1. Pallidosubthalamic fibers arising in the lateral pallidal segment are topographically organized so that: (a) rostral and central regions of this segment project fibers to the rostral two-thirds of the subthalamic nucleus, and (b) rostral parts of this segment project fibers to the medial half of the subthalamic nucleus and central parts of this segment project fibers to the lateral half of the nucleus. 2. 2. Dorsal and ventral regions of the rostral and central parts of the lateral pallidal segment are organized topographically so that: (a) fibers from dorsal regions of the rostral part terminate in lateral areas of the medial half of the subthalamic nucleus, while ventral regions project to more medial parts of this half of the nucleus, and (b) dorsal and ventral regions of the central part of this pallidal segment project to corresponding dorsal and ventral regions of the subthalamic nucleus. 3. 3. Caudal parts of the lateral pallidal segment project fibers to dorsolateral regions of the caudal part of the subthalamic nucleus. 4. 4. Observations in the present study suggest that pallidosubthalamic fibers terminating in medial and caudal parts of the subthalamic nucleus probably are derived from the medial pallidal segment. The hypothesis is presented that pallidosubthalamic fibers are topographically organized so that: (a) the most medial and lateral regions of the lateral pallidal segment project fibers respectively to medial and la

关键词： AC anterior commissure III third ventricle CL subthalamic nucleus Lf lenticular fasciculus CN caudate nucleus LG lateral geniculate body f fornix OC optic chiasm GPl globus pallidus, lateral segment OT optic tract GPm globus pallidus, medial segment Ped peduncular part of internal capsule H 2 lenticular fasciculus Put putamen IC internal capsule SN substantia nigra

来源：评论

学校读者我要写书评

暂无评论

LOCUS fOR RADIATION SENSITIVITY IN ESCHERICHIA COLI B3

引用

MUTATION RESEARCH 1965年第4期2卷 297-+页

作者： GREENBERG, J Palo Alto Medical Research Foundation Palo Alto Calif. U.S.A.

The locus of the gene for radiation sensitivity in Escherichia coli BIII has been found in crosses with several K12 Hfr''s to be closely linked to the his marker. Despite the fact that BIII, a derivative of strain B, differs from the K12 donor in two radiation-sensitivity genes, only one type of radiation-resistant recombinant was observed, that resembling the donor parent.

关键词： met methionine his histidine try tryptophane thi thiamine mal maltose str streptomycin val valine UV ultraviolet light Hfr high frequency male or donor f − recipient or female for met his try and thi minus indicates inability to synthesizel for mal minus indicates inability to ferment for val str and UV r indicates resistance s indicates sensitivity HCR(−) host cell recovery negative HCR(+) host cell recovery positive

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：