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1.
其它药剂     
<正>本文介绍了结构式(I)这种化合物及其盐类。R是结构式(Ⅱ)和(Ⅲ)的一个基团。在(Ⅱ)中R是羟基,缺失裂解的键,或替代R产是H,裂解的键是双键。结构式(Ⅰ)是抗菌的化合物,对革兰氏阳性菌株特别有效。这类化合物还是抗肿瘤剂  相似文献   

2.
为了合理利用和保护天敌进行卵形短须螨、双斑长跗萤叶甲和假眼小绿叶蝉的综合防治,用灰色系统分析方法和生态位分析法对合肥地区白毫早茶园3种主要害虫与其捕食性天敌在数量、时间、空间等方面关系进行分析,利用害虫与天敌关系密切指数之和综合评判9种天敌与3种害虫关系密切的前四位天敌。2015年卵形短须螨的前四位天敌是鳞纹肖蛸(5.3079)、三突花蟹蛛(5.1716)、锥腹肖蛸(4.8367)和草间小黑蛛(4.7869);2016年前四位天敌依次是三突花蟹蛛(5.3975)、鳞纹肖蛸(4.9414)、茶色新圆蛛(4.8757)、锥腹肖蛸(4.6815)。对两年结果综合分析,卵形短须螨的前四位天敌依次是三突花蟹蛛(10.5691)、鳞纹肖蛸(10.2493)、茶色新圆蛛(9.6353)和锥腹肖蛸(9.5182)。2015年双斑长跗萤叶甲的前四位天敌依次是锥腹肖蛸(5.6926)、异色瓢虫(5.6976)、八斑球腹蛛(5.5101)和斜纹猫蛛(5.4552);2016年依次是茶色新圆蛛(5.2909)、锥腹肖蛸(5.2710)、鳞纹肖蛸(5.1063)和斜纹猫蛛(5.0703)。对两年结果综合评判,双斑长跗萤叶甲的前四位天敌是锥腹肖蛸(10.9636)、茶色新圆蛛(10.6578)、异色瓢虫(10.7580)和鳞纹肖蛸(10.5437)。2015年假眼小绿叶蝉的前四位天敌依次是锥腹肖蛸(5.3614)、粽管巢蛛(5.2259)、斜纹猫蛛(5.1300)和茶色新圆蛛(4.7472);2016年是锥腹肖蛸(5.2666)、粽管巢蛛(5.2561)、草间小黑蛛(4.9376)和斜纹猫蛛(4.8335)。对两年结果综合评判,假眼小绿叶蝉的前四位天敌依次是锥腹肖蛸(10.6280)、粽管巢蛛(10.4820)、斜纹猫蛛(9.9635)和茶色新圆蛛(8.6137)。该研究结果为白毫早茶园3种害虫防治时合理保护和利用自然界的天敌的种类提供了科学依据。  相似文献   

3.
载脂蛋白(a)简称 apo(a),是脂蛋白(a)(Lp(a))中特征性蛋白成分,分子量在400—700kD,apo(a)以二硫键与低密度脂蛋白(LDL)的载脂蛋白 B100相连构成 Lp(a),分子量在1 200—1 500kD。近年来国内外学者认为 Lp(a)和 apo(a)是研究动脉粥样硬化危险因素的重要指标。我们为了探索脂质代谢紊乱引起的心血管系统疾病,进行了apo(a)的单克隆抗体研究。apo(a)提取的脂蛋白 Lp(a)经密度为  相似文献   

4.
唇形科鼠尾草属的物种多样性与分布   总被引:1,自引:0,他引:1  
为全面了解唇形科鼠尾草属(Salvia)植物的多样性和分布格局及其形成机制, 作者查阅了国际权威生物多样性信息网站(GBIF, The Plant List)、中国数字植物标本馆(CVH)、教学标本资源共享平台和中国自然保护区标本资源共享平台中该属物种名称及标本采集信息, 以及国内32家标本馆的标本, 分析并绘制其物种分布图。结果显示, 具有明确地理坐标的世界和中国分布信息分别有57,674条和11,596条, 已接受种名952个。在世界范围内, 以中南美洲(510种)物种数量最多, 其次是西亚(270种)、欧洲(117种)、东亚(97种)和北美(94种); 在国家尺度上, 以墨西哥物种数量最多(322种), 其次是俄罗斯(109种)、土耳其(88种)、美国(85种)和中国(82种)。在中国, 以云南和四川省鼠尾草种数最多(合计占全国的63%), 两省分布最多的县域地区分别是玉龙县(23种)、香格里拉县(20种)、大理市(13种)和木里县(17种)、宝兴县(13种)、马边县(13种)。在自然地理区域上, 以横断山区最为丰富, 占该属全国物种总数的52.8%, 特有种达23种; 广布种以荔枝草(S. plebeia)分布的县域数量最多(395县), 其次是鼠尾草(S. japonica) (199)、丹参(S. miltiorrhiza) (192)、贵州鼠尾草(S. cavaleriei) (173)、华鼠尾草(S. chinensis) (153)和粘毛鼠尾草(S. roborowskii) (100)。鼠尾草属主要分布于北半球温带及亚热带高海拔地区, 中国是东亚的多样性分布中心, 代表性广布种及狭域特有种均有分布, 尤以云南、四川以及横断山区的物种多样性和特有种比例最高。  相似文献   

5.
在马(Equus caballus)的繁殖和非繁殖季节,本研究探讨马扩展型(Ex)和紧凑型(Cp)卵丘-卵母细胞复合体(COCs)卵母细胞的孤雌激活效率。在繁殖季节,探讨马驹和成年马成纤维细胞核移植(SCNT)的成功率。孤雌激活实验结果显示,在繁殖季节,发育到2-细胞、4-细胞和桑椹胚的比例,扩展型(Ex)卵丘-卵母细胞复合体分别是52.8%(19/36)、38.9%(14/36)和5.6%(2/36),紧凑型(Cp)卵丘-卵母细胞复合体分别是47.9%(23/48)、33.3%(16/48)和6.2%(3/48)。在非繁殖季节,发育到2-细胞、4-细胞的比例,扩展型(Ex)分别是37.2%(16/43)和16.3%(7/43),紧凑型(Cp)的比例分别是35.1%(27/77)和11.7%(9/77),都没有获得桑椹胚。同一季节,扩展型(Ex)与紧凑型(Cp)胚胎发育的比率差异不显著(P 0.05),不同季节,两者差异显著(P 0.05)。体细胞核移植实验结果显示,以马驹成纤维细胞作为核供体细胞,胚胎发育到2-细胞、4~8细胞和桑椹胚的比例分别是41.5%(22/53)、33.9%(18/53)和15.1%(8/53),以成年马成纤维细胞作为核供体细胞,比例分别是38.9%(7/18)、22.2%(4/18),没有获得桑椹胚。综上所述,季节和卵丘-卵母细胞复合体(COCs)类型影响马卵母细胞孤雌激活的效率,不同核供体细胞影响克隆胚胎构建的成功率。  相似文献   

6.
本文报道了7种安徽省鸟类分布新纪录,分别为黑脸琵鹭(Platalea minor)、沙丘鹤(Grus canadensis)、黑雁(Branta bernicla)、黄眉姬鹟(Ficedula narcissina)、鳞头树莺(Urosphena squameiceps)、黑眉柳莺(Phylloscopus ricketti)以及红颈苇鹀(Emberiza yessoensis)。其中黑脸琵鹭、沙丘鹤和黑雁是迷鸟,黄眉姬鶲、鳞头树莺和红颈苇鹀是旅鸟,黑眉柳莺是夏候鸟。  相似文献   

7.
植物生理学试题1名词解释(20分) (1)光呼吸(2)光补偿点 (3、合理密植(4)光周期 (5)生长素氧化酣(6)玉米素 (7)酸生长学说(8)蒸腾系数 (9)根压(10)生理酸性盐2.填充题(20分) (1)光合磷酸化有两种类型,一种叫____, 另一种叫 (2)光合作用和硝酸还原的关系是__,当 光强度高时,有较多的光合产物运到细胞 质中,这些化合物在细胞质中参加__ 反应形成N人DPH,于是硝酸盐还原反应 加速。 (3)经济产景。(光合面积丫_又光合时 间一光合产物的消耗)又 (4)_是一种植物激素,它可似促进气 孔的关闭,这一反应是由_细胞 来调控的。 (勿光敏素是一种_,它与的…  相似文献   

8.
中国鮡科鱼类RAPD分析及鰋鮡鱼类单系性的初步研究   总被引:5,自引:0,他引:5  
鱼类已被形态学证明是(鱼兆)科鱼类的一个自然类群,包括原(鱼兆)属(Glyptosternum)、石爬(鱼兆)属(Euchiloglanis)、(鱼兆)属(Pareuchiloglanis)、(鱼兆)属(Exostoma)等9属31个种。    相似文献   

9.
Harpin_(Pss)诱导的烟草早期防卫反应及钙的参与   总被引:1,自引:0,他引:1  
Harpin_(Pss)可引发烟草过敏反应。超氧化物歧化酶能抑制,而过氧化氢酶不能抑制harpin_(Pss)诱导产生的这个反应,表明是超氧阴离子(O_2~-)是harpin_(Pss)诱导的烟草过敏反应的必要因子。Harpin_(Pss)还可引起烟草悬浮细胞活性氧的释放和胞外碱性化这两个早期防卫反应。Diphenylene iodonium能消除这种活性氧的诱导,这提示harpin_(Pss)可能是通过诱导NADPH氧化酶而产生O_2~_的。EGTA在无Ca~(2 )培养基中,能消除harpin_(Pss)诱导的烟草悬浮培养物的这两种防卫反应,再向培养基加Ca~(2 ),可恢复harpin_(Pss)的效应。LaCl_3、verapamil、新霉素、U-73122和LiCl也能抑制harpin_(Pss)诱导的这些反应,这表明由Ca~(2 )通道介导的Ca~(2 )内流和胞内Ca~(2 )库中Ca~(2 )的释放也参与了harpin_(Pss)诱导的早期防卫反应和过敏反应。在加harpin_(Pss)后很长时期内加放线菌素D、环己亚胺,都能抑制由它引发的过敏性细胞坏死过程,但它们对harpin_(Pss)诱导的活性氧的产生没有影响。表明O_2~-只是harpin_(Pss)诱发过敏性细胞凋亡的一个促发信号,过敏反应是更复杂的过程,需有基因持续地表达。  相似文献   

10.
白鱀豚(Lipotesvexillifer)是仅分布于我国长江中下游水域的一种珍稀濒危动物。长江水体污染(如有毒元素等)被认为可能是白鱀豚种群致危的主要因素之一(Yang,1997)。迄今,有关白鱀豚体内微量元素的研究尚很少,只有陆佩洪等(1983)、杨利寿等(1988)曾报道过白鱀豚组织中铁(Fe)、铜(Cu)、锌(Zn)、锰(Mn)、镍(Ni)、铅(Pb)、汞(Hg)和镉(Cd)在某些组织器官中的积累水平。本文对1头饲养条件下白鱀豚“淇淇”体内的必需元素Cu、Zn、锰(Mn)、钼(Mo)、硒(Se)和有毒或非必需元素砷(As)、Cd、铝(Al)的积累特征进行了报道,以期为白豚的保护提供…  相似文献   

11.
The hemolysate of the Antarctic teleost Gobionotothen gibberifrons (family Nototheniidae) contains two hemoglobins (Hb 1 and Hb 2). The concentration of Hb 2 (15-20% of the total hemoglobin content) is higher than that found in most cold-adapted Notothenioidei. Unlike the other Antarctic species so far examined having two hemoglobins, Hb 1 and Hb 2 do not have globin chains in common. Therefore this hemoglobin system is made of four globins (two alpha- and two beta-chains). The complete amino-acid sequence of the two hemoglobins (Hb 1, alpha2(1)beta2(1); Hb 2, alpha2(2)beta2(2)) has been established. The two hemoglobins have different functional properties. Hb 2 has lower oxygen affinity than Hb 1, and higher sensitivity to the modulatory effect of organophosphates. They also differ thermodynamically, as shown by the effects on the oxygen-binding properties brought about by temperature variations. The oxygen-transport system of G. gibberifrons, with two functionally distinct hemoglobins, suggests that the two components may have distinct physiological roles, in relation with life style and the environmental conditions which the fish may have to face. The unique features of the oxygen-transport system of this species are reflected in the phylogeny of the hemoglobin amino-acid sequences, which are intermediate between those of other fish of the family Nototheniidae and of species of the more advanced family Bathydraconidae.  相似文献   

12.
铁传递蛋白(transferrin)是血浆中除免疫球蛋白外功能比较明确的一种非酶蛋白质,电泳图谱上位于β部位,所以早期有β球蛋白之称。这个名称是不够确切的,因为β球蛋白并不都是铁传递蛋白。后来人们一致用它的功能性名称,即铁传递蛋白(以下简称传铁蛋白)。 传铁蛋白由于功能上的重要性,招徕广泛的注意。生物化学家和病理学家感兴趣的是它的结构和功能的研究,这方面的工作近年来进展很快(Makey等,1976;Aisen等,1978;Harrison等,1979)。种群遗传学家感兴趣的是它的遗传变异以及如何用于优种的选育。此外,传铁蛋白的生化多态性的比较也已为分类学家用于分类的一个重要指标(Chapman等,1973)。  相似文献   

13.
1. The electrophoretic mobilities of the hemoglobins of 7 taxa of microtines were compared. Microtus oeconomus, M. pennsylvanicus pullatus and M. xanthognatus showed identical 2-band patterns on electrophoresis of their hemoglobins while M. pennsylvanicus tananaensis showed only a single hemoglobin corresponding to the major band of the others. Dicrostonyx rubricatus and D. stevensoni exhibited identical patterns different from the Microtus species. Lemmus sibiricus had a slow hemoglobin component with mobility slightly different from the slow ones of the Microtus species while the fast component appeared the same. 2. Electrophoresis of individual globin chains from hemolysates, purified hemoglobins, and isolated chains indicated a large degree of similarity between the species studied, although there were significant differences in hemoglobin patterns. 3. The minor hemoglobin band in Microtus seems to be the result of a second alpha chain locus as determined from the hemoglobins from hybrids of two subspecies. 4. Salting-out studies indicated differences between hemoglobins that were not detectable by electrophoresis of either whole hemoglobins or isolated chains. 5. M. xanthognathus hemolysate was considerably less soluble than those of M. oeconomus and M. pennsylvanicus pullatus which had essentially the same solubility. 6. The major hemoglobin components of M. pennsylvanicus pullatus and M. xanthognathus were considerably less soluble than either the corresponding unfractionated hemolysates or purified minor components.  相似文献   

14.
The hemoglobins of the four karyotypes of Spalax ehrenbergi (2n = 52, 54, 58, 60) did not show any differences in their electrophoretic pattern and in high performance liquid chromatography. The complete amino-acid sequence of mole rat hemoglobin (Spalax ehrenbergi), chromosome species 2n = 52, is presented. It was elucidated by automatic Edman degradation of the chains, the tryptic peptides, and the C-terminal peptide obtained by acid hydrolysis of the Asp-Pro bond in beta-chains. The alpha- and beta-chains are identical with those of the chromosome species 2n = 60. A comparison of the hemoglobins of mole rat, mouse, and other rodents shows homology but no indication of adaptation to subterranean life. In all probability alpha 11(A9)Arg and alpha 120(H3)Gly, unique in mole rat among all mammalian hemoglobins, are not involved in high oxygen affinity. The construction of a phylogenetic tree by the maximum parsimony method, based on hemoglobin sequences, made it possible to show that Rodentia originated as a monophyletic clade, and to find the phylogenetic relationship of Spalacidae to other Rodentia (Mus, Rattus, Ondatra, Mesocricetus, Citellus, and Cavia). Among all rodents the slowest rate of nucleotide replacements occurred in the lineage to Spalax (20%) and the fastest in the lineage to Cavia (59%).  相似文献   

15.
The complete primary structure of the two hemoglobin components of the Great Indian Rhinoceros (Rhinoceros unicornis) is presented. The ratio for the two components B(alpha 2 beta I2): A(alpha 2 beta II2) is 6:4. Polypeptide subunits were separated by chromatography on CM-cellulose in a buffer containing 8M urea. The sequence was studied by degradation of the tryptic and hydrolytic cleavage products in a liquid phase sequencer. At position beta NA2 component B has Asp, whereas component A has Glu, an ATP-binding site in fish and reptilian hemoglobins. The other phosphate binding sites i.e. beta NA1 Val, beta EF6 Lys and beta H21 His are identical with 2,3-bisphosphoglycerate-(DPG)binding sites in mammalian hemoglobins, whereby rhinoceros hemoglobin resembles both ATP-sensitive poikilotherm hemoglobin and DPG-sensitive mammalian hemoglobin. The two components (beta I/beta II) additionally differ by exchange of Glu----Gly at position beta A3 and Gln----Lys at position beta GH3. The significance of these changes is discussed. Oxygenation properties of the two hemoglobins components and their dependence on ATP and DPG are given. The structure and function of Rhinoceros hemoglobin may give an insight into the evolution of the organic phosphate binding in vertebrate hemoglobins.  相似文献   

16.
The tetramer-dimer dissociation equilibria (K 4,2) of several fish hemoglobins have been examined by sedimentation velocity measurements with a scanner-computer system for the ultracentrifuge and by flash photolysis measurements using rapid kinetic methods. Samples studied in detail included hemoglobins from a marine teleost, Brevoortia tyrannus (common name, menhaden); a fresh water teleost, Cyprinus carpio, (common name, carp); and an elasmobranch Prionace glauca (common name, blue shark). For all three species in the CO form at pH 7, in 0.1 M phosphate buffer, sedimentation coefficients of 4.3 S (typical of tetrameric hemoglobin) are observed in the micromolar concentration range. In contrast, mammalian hemoglobins dissociate appreciably to dimers under these conditions. The inability to detect dissociation in three fish hemoglobins at the lowest concentrations examined indicates that K 4,2 must have a value of 10(-8) M or less. In flash photolysis experiments on very dilute solutions in long path length cells, two kinetic components were detected with their proportions varying as expected for an equilibrium between tetramers (the slower component) and dimers (the faster component); values of K 4,2 for the three fish hemoglobins in the range 10(-9) to 10(-8) M were calculated from these data. Thus, the values of K 4,2 for liganded forms of the fish hemoglobins appear to be midway between the value for liganded human hemoglobin (K 4,2 approximately 10(-6) M) and unliganded human hemoglobin (K 4,2 approximately 10(-12) M). This conclusion is supported by measurements on solutions containing guanidine hydrochloride to enhance the degree of dissociation. All three fish hemoglobins are appreciably dissociated at guanidine concentrations of about 0.8 M, which is roughly midway between the guanidine concentrations needed to cause comparable dissociation of liganded human hemoglobin (about 0.4 M) and unliganded human hemoglobin (about 1.6 M). Kinetic measurements on solutions containing guanidine hydrochloride indicated that there are changes in both the absolute rates and the proportions of the fast and slow components, which along with other factors complicated the analysis of the data in terms of dissociation constants. Measurements were also made in solutions containing urea to promote dissociation, but with this agent very high concentrations (about 6 M) were required to give measureable dissociation and the fish hemoglobins were unstable under these conditions, with appreciable loss of absorbance spectra in both the sedimentation and kinetic experiments.  相似文献   

17.
The structure and function of plant hemoglobins.   总被引:1,自引:0,他引:1  
Plants, like humans, contain hemoglobin. Three distinct types of hemoglobin exist in plants: symbiotic, non-symbiotic, and truncated hemoglobins. Crystal structures and other structural and biophysical techniques have revealed important knowledge about ligand binding and conformational stabilization in all three types. In symbiotic hemoglobins (leghemoglobins), ligand binding regulatory mechanisms have been shown to differ dramatically from myoglobin and red blood cell hemoglobin. In the non-symbiotic hemoglobins found in all plants, crystal structures and vibrational spectroscopy have revealed the nature of the structural transition between the hexacoordinate and ligand-bound states. In truncated hemoglobins, the abbreviated globin is porous, providing tunnels that may assist in ligand binding, and the bound ligand is stabilized by more than one distal pocket residue. Research has implicated these plant hemoglobins in a number of possible functions differing among hemoglobin types, and possibly between plant species.  相似文献   

18.
The primary structures of the hemoglobins Hb A, Hb A', Hb D and Hb D' of Rüppell's Griffon (Gyps rueppellii), which can fly as high as 11,300 m, are presented. The globin chains were separated on CM-Cellulose in 8M urea buffers, the four hemoglobin components by FPLC in phosphate buffers. The amino-acid sequences of five globin chains were established by automatic Edman degradation of the globin chains and of the tryptic peptides in liquid-phase and gas-phase sequenators. The sequences are compared with those of other Falconiformes. A new molecular pattern for survival at extreme altitudes is presented. For the first time four hemoglobins are found in blood of a bird; they show identical beta-chains and differ in the alpha A- and alpha D-chains by only one replacement. These four hemoglobins cause a gradient in oxygen affinities. The two main components Hb A and Hb A' differ at position alpha 34 Thr/Ile. In case of Ile as found in Hb A' an alpha 1 beta 1-interface is interrupted raising oxygen affinity compared to Hb A. In addition the hemoglobins of the A- and D-groups differ at position alpha 38 Pro or Gln/Thr (alpha 1 beta 2-interface). Expression of Gln in Hb D/D' raises the oxygen affinity of these components compared to Hb A/A' by destabilization of the deoxy-structure. The physiological advantage lies in the functional interplay of four hemoglobin components. Three levels of affinity are predicted: low affinity Hb A, Hb A' of intermediate affinity, and high affinity Hb D/D'. This cascade tallies exactly with oxygen affinities measured in the isolated components and predicts oxygen transport by the composite hemoglobins over an extended range of oxygen affinities. It is contended that the mechanisms of duplication of the alpha-genome (creating four hemoglobins) and of nucleotide replacements (creating different functional properties) are responsible for this remarkable hypoxic tolerance to 11,300 m. Based on this pattern the hypoxic tolerances of other vultures are predicted.  相似文献   

19.
Erythrocytes of the adult axolotl, Ambystoma mexicanum, have multiple hemoglobins. We separated and purified two kinds of hemoglobin, termed major hemoglobin (Hb M) and minor hemoglobin (Hb m), from a five-year-old male by hydrophobic interaction column chromatography on Alkyl Superose. The hemoglobins have two distinct alpha type globin polypeptides (alphaM and alpham) and a common beta globin polypeptide, all of which were purified in FPLC on a reversed-phase column after S-pyridylethylation. The complete amino acid sequences of the three globin chains were determined separately using nucleotide sequencing with the assistance of protein sequencing. The mature globin molecules were composed of 141 amino acid residues for alphaM globin, 143 for alpham globin and 146 for beta globin. Comparing primary structures of the five kinds of axolotl globins, including two previously established alpha type globins from the same species, with other known globins of amphibians and representatives of other vertebrates, we constructed phylogenetic trees for amphibian hemoglobins and tetrapod hemoglobins. The molecular trees indicated that alphaM, alpham, beta and the previously known alpha major globin were adult types of globins and the other known alpha globin was a larval type. The existence of two to four more globins in the axolotl erythrocyte is predicted.  相似文献   

20.
1. Dual hemoglobins were isolated from both Lemmus and Discrostonyx, two genera of microtine rodents of the tribe Lemmini. 2. The dual hemoglobins result from dual alpha-chains and the charge difference Asp----Ala at position alpha 5. 3. The beta-chains of Dicrostonyx and Lemmus hemoglobins differ in charge by Ala----Asp at beta 125. 4. Cladograms are presented for the hemoglobin chains of microtine rodents.  相似文献   

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