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31.
<正> 本文报道以pAT153质粒为载体克隆的adr亚型乙型肝炎病毒(HBV)全基因的限制性内切酶图谱。重组质粒已命名为pHBV-NCl。重组质粒的提取和酶解采用常规方法。限制性内切酶为Bio-Labs公司产品。用Sepharcry S-1000纯化得到的质粒,经电泳鉴定都是完整的超螺旋DNA。经过鉴定其BamHⅠ、XhoⅠ、XbaⅠ、SstⅡ、SphⅠ、BglⅠ、BglⅡ、BstEⅡ、AceⅠ、AvaⅠ、HincⅡ、HpaⅠ等12种酶的21个切口已被定位。其中XhoⅠ、XbaⅠ、SstⅡ、 相似文献
32.
<正> 我们实验室曾报道,用胆酸盐透析法将猪心线粒体H~+-ATP酶嵌入大豆磷脂脂质体形成脂酶体时,透析液中Mg~(2+)的存在会降低脂酶体的膜脂流动性,并明显提高重建H~+-ATP酶的活性以及对寡霉素或DCCD的敏感性,因而推论Mg~(2+)的作用很可能是通过改变膜脂的物理状态,形成了维持H~+-ATP酶较高活性的合适构象。但共确切的作用机制仍 相似文献
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棕色固氮菌中电子载体Fld直接向固氮酶铁蛋白传递电子。Fld_(ox)至Fld_R是双电子二步还原反应,极谱半波电位分别为-210、-550 mV。Fld_(ox)至Fld_(SR)的中点电位为-280 mV,Fld_(SR)至Fld_R为-500mV。铁蛋白中点电位为-256mV,加MgATP后为-390 mV。Fld_R与铁蛋白ox组成的电池电动势为244mV,电子传递可自发进行,反应的J△G~o为-23KJ/摩尔,铁蛋白被Fld_R还原的K_a=1.3×120~4,加入MgATP后△G~o为-10.6KJ/摩尔,K_a=72。因此,未加入MgATP时电子传递反应更易进行。 相似文献
35.
Summary A prospective randomized trial compared the administration of intrapleural plus intravenous Corynebacterium parvum (C. parvum) versus placebo in patients with resected Stage I and Stage II non-small cell bronchogenic carcinoma. Treatment consisted of 7 mg C. parvum injected into the pleural space and 7 mg C. parvum intravenously once between days 6 and 12 postoperatively and 7 mg intravenously every 3rd month during the 1st year. Intrapleural administration of 35 cc of saline served as the placebo and the flush after intrapleural C. parvum.Of the 303 patients entered into this study, 286 were evaluable, with an average follow-up time of 3.5 years. More complications, especially fever, were observed in patients receiving C. parvum. A fever greater than 38 °C was observed in 9% of the patients assigned to placebo and 76% of the patients assigned to C. parvum. There was no significant difference between the treatments with respect to disease-free interval or survival.M. Kaufmann, J. Stjernswärd**, A. Zimmermann (Ludwig Institute for Cancer Research, Bern Branch); K. Stanley**, M. Isley, M. Zelen (Frontier Science & Tech. Research Foundation, Brookline, MA, USA); C. Mouritzen, P. Paulsen, U. Henriques (Dept. of Thoracic and Cardiovascular Surgery and Institute of Pathology, Kommunehospital, Aarhus, Denmark); N. Konietzko, W. Maassen, W. Hartung, W. Wierich (Ruhrland Clinic, Essen-Heidhausen, and Pathology Institute, Ruhr-University, Bochum, FRG); P. Oehl (Innere Klinik und Poliklinik Tumorforschung, Essen, FRG); J. Vogt-Moykopf, H. Toomes, W. Hofmann (Rohrbach Hospital, Clinic for Thoracic Medicine and Pathology Institute, Heidelberg, FRG); F. Krause, R. Rios, R. Spanel (Klinik Löwenstein, Löwenstein, and Pathology Institute, Ulm, FRG); J. Orel, B. Hrabar, D. Ferluga, T. Rott (University Medical Center, Thoracic Surgery and Pathology, Ljubljana, Yugoslavia); H. A. Rostad, J. R. Vale, P. Lexow (Rikshospital, Oslo, Norway); S. Hagen, S. Birkeland (Ulleval Hospital, Oslo, Norway); T. Harbitz, R. Nissen-Meyer (Aker Hospital, Oslo, Norway); E. Aspevik, H. Engedal, A. Mykin (Haukeland Hospital, Bergen, Norway); V. O. Björk, L. Rodriguez, K. Böök, J. Willems (Karolinska Sjukhuset, Thoracic Surgical Clinic and Pathology Department, Stockholm, Sweden); E. Grädel, J. Hasse, P. Dalquen (Kantonsspital, Dept of Surgery, Div. of Cardiac & Thoracic Surgery & Pathology Institute, Basel, Switzerland); L. Eckmann, K. Hänni, K. Zimmermann (Tiefenauspital Surg. Clinic, Univ. of Bern, Switzerland); B. Nachbur, H. U. Würsten, H. Cottier, A. Zimmermann (Inselspital Dept. of Thoracic and Cardiovascular Surg. and Pathology Institute, Bern, Switzerland); W. Maurer, M. Kaufmann (Bürgerspital, Surgical Department, Solothurn, Switzerland); H. Denck, E. Zwintz, St. Wuketich (Krankenhaus der Stadt Wien-Lainz, I. Chir. Dept., and Path. Inst., Vienna, Austria); N. Pridun, H. Hackl (Pulmonologisches Zentrum der Stadt Wien, and Path. Inst., Vienna, Austria); E. Moritz, W. Schlick, H. Holzner (II. Chir. University Clinic and Path. Inst., Vienna, Austria); K. Karrer (Institute for Cancer Research, Vienna, Austria); R. G. Crispen (ITR-Biomedical Research, University of Illinois, Chicago, USA); D. S. Freestone, R. Bomford, M. T. Scott, T. Priestman, L. Toy (The Wellcome Research Laboratories, Beckenham, England)** Present address: Cancer Unit, World Health Organization, Geneva, Switzerland
Offprint requests to: K. Stanley, Ludwig Institute for Cancer Research, Inselspital, CH-3010 Bern, SwitzerlandLudwig Lung Cancer Study Group: 相似文献
36.
宁夏同心中新世铲齿象化石 总被引:8,自引:6,他引:2
本文记述了宁夏同心地区中中新世哺乳动物群中铲齿象化石——同心铲齿象 (Platybelodon tongxinensis) (原定为同心嵌齿象 (Gomphotherium tongxinensis). 通过与国内外已现的有关铲齿象对比,确认其与国内已发现的葛氏种关系最近,可能属同一枝系.同心种与葛氏种相比,是性质相对原始分布层位较低的我国第二个铲齿象种.文章初步讨论了其 M_3 的某些变异性状.并结合现有的其它标本初步阐述了铲齿象类下门齿的两种结构类型,原始型的同心层状结构和衍生型的齿质柱状结构.建议根据这两种结构仍将铲齿象类划分为 Platybelodontinae 和 Amebelodontinae. 相似文献
37.
On primary infection with the Bryan strain of Rous sarcoma virus (RSV), the growth curve of the virus in the brain of Japanese quail was similar to that observed in chicks and turkey poults. Infectious virus disappeared from the brain after inoculation. After an eclipse period during which no virus was detectable, infectious virus began to appear at 2 days and reached maximal titers in the brain samples at 7 days after inoculation. When Japanese quail were infected intracerebrally with RSV, relatively high titers of virus were recovered from brain tissue but not from liver, lung, kidney, or blood of moribund birds. Only tumors produced in the wing web of quail infected subcutaneously yielded high titers of virus. Other tissues yielded no virus, even though wing web tumors appeared as early as in chicks similarly infected. RSV could be propagated in the wing web of quail for at least 14 passages without any loss of infectivity. On the other hand, serial passage in quail brain resulted in a progressive loss of infectivity until virus was completely lost. 相似文献
38.
Factors Controlling the Production of Lysogenic Cultures of B. megatherium 总被引:1,自引:1,他引:0 下载免费PDF全文
John H. Northrop with the technical assistance of Marie King 《The Journal of general physiology》1961,44(5):859-867
(1) The proportion of infected B. megatherium cells which develop lysogenic colonies depends on the number and kind of infecting virus particles and on the culture medium in which the cells are growing. (2) Cells infected with 100 or more T virus particles (from megatherium 899) in yeast extract peptone disintegrate, produce very few virus particles, and less than one lysogenic colony per 107 infected cells. Cells infected with one or a few particles produce 500 to 1000 virus particles each and about 30 lysogenic colonies per 107 infected colonies. (3) T phage obtained from lysogenic magatherium KM cultures produces many more lysogenic cells than does the original megatherium 899 virus. (4) Cells infected with megatherium 899 T virus in peptone medium and then transferred to asparagine medium give rise to 106 lysogenic colonies per 107 infected cells and this transformation will occur even after the infected cells have been in peptone for 60 to 90 minutes and are beginning to produce virus particles. (5) Continued growth of KM strain with either C or T virus from megatherium 899 for several hundred generations in the steady state apparatus results in a lysogenic strain which produces several different types of virus. 相似文献
39.