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1.
The formation of ternary complexes, transferrin-anion-In111 has been investigated by means of gamma-gamma coincidence spectrometry of the 172-245 keV rays. The angular correlation between the two gamma-rays emitted in cascade depends on the magnetic and electric fields gradients, consequently the chemical structure of metal holder. Any modification of this structure causes the variation of angular correlation. The study of G22 (infinity) as function of pH (G22(infinity): integrated perturbed angular correlation coefficient) has been performed to turn out the hydrolysis of In111 in aqueous solution, metal complex formation in presence of chelating agents (citric acid and sodium bicarbonate) and the formation of protein-metal complexes. The presence of complexing agents limits the domain of In111 colloid existence and allows fast transfer of ionised indium on the transferrin. Two types of metal-protein interactions has been turn out. The first in the weakly acidic range of pH is characterized by an affinity constant near to this of citric acid. The second lying in neutral and basic range of pH, where the formation rate of transferrin-In111 complex is fast (t less than 500 s). In citrate medium, for pH 6-7,5 the rate of metal transfer on the protein, studied by means of G22 (infinity) = f(t), is function of pH. The binding anion appears as an indispensable element for the formation of protein-metal complexes. The In111 previously chelated by 8-Hydroxyquinoline is fixed by the protein if only exits a binding anion in the solution. This mays bring in the formation of an intermediate active state, indispensable step for the ternary complex formation transferrin-anion-In111.  相似文献   

2.
寒武系腕足动物属种多样性高、个体数量丰富、形态差异明显、地理分布广泛,具有辅助寒武系三叶虫生物地层划分和对比的潜力.华北板块寒武系苗岭统沉积和化石记录发育良好,是中国苗岭统的经典研究区之一.前人己针对华北寒武系苗岭统乌溜阶腕足动物的系统古生物学开展了一系列基础工作,但这些相关研究主要集中于辽宁地区,目前对华北其他地区苗...  相似文献   

3.
    
《Annales de Paléontologie》2017,103(4):271-281
Additional Cambrian Series 3, Stage 5, trilobite fauna comprising Peronopsis sp., Eosoptychoparia cf. Spinosa Gaotanaspis cf. pingzhaiensis and Gaotanaspis cf. transversa have been recorded just immediately above the known Oryctocephalus indicus biozone (Cambrian Series 3, Stage 5) in the Parahio valley section (Spiti region). The FAD of Peronopsis and LAD of Gaotanaspis are used to establish a PeronopsisGaotanaspis concurrent biozone immediately above the Oryctocephalus indicus biozone. The first records of Gaotanaspis cf. pingzhaiensis and G. transversa from the Cambrian of Spiti region and the other faunal elements are correlated with the Peronopsis taijiangensis biozone of the Kaili Formation (South China). The stratigraphic thickness from the base of the O. indicus biozone to the top of the PeronopsisGaotanaspis concurrent biozone in the Kunzam La (=Parahio) Formation and its comparison to the Kaili Formation (South China) indicate a possible stratigraphic condensation in the basal part of the Cambrian Series 3, Stage 5 of the Parahio valley (Spiti). Sedimentological and sequence stratigraphic analysis supports this contention.  相似文献   

4.
太阳女神螺类(helcionellids)是寒武纪常见的一类软体动物,广布全球,多见于碳酸盐岩沉积地层中,而布尔吉斯页岩型生物群中却少有报道。贵州剑河凯里生物群是典型的特异埋藏化石库,产有700余件太阳女神螺类标本,这在世界各地同时期的布尔吉斯页岩型生物群中是很少见的。本文对贵州剑河八郎寒武系凯里组太阳女神螺类化石标本进行了系统研究,采用几何形态测量学的典型变量分析进行量化分析。几何形态测量学(Geometric morphometrics)是用界标点或轮廓线等来描绘生物的形态或者标记特征部位及器官,将生物形态特征归纳为数据变化的定量学方法,其中的典型变量分析(Canonical Variate Analysis)是多变量分析中进行判别分析的一个重要方法,可以用于多组数据之间的判别。CVA判别结果显示:利用壳体侧视轮廓线判别Dorispira属中三个种的正确率为92%,验证了Dorispira accordinonata、D.taijiangensis和D.cf.pearylandica化石种分类合理性。本文研究表明即使壳体形态较为相似的类群,也可以较为准确地使用CVA量化其中的差别,...  相似文献   

5.
贵州剑河八郎寒武系苗岭统乌溜阶凯里组中保存了大量三叶虫化石,并见有众多三叶虫蜕壳记录。本文从308块贵州东方褶颊虫(Eosoptychoparia guizhouensis)中选取出25块蜕壳标本进行研究,根据头盖、活动颊及腹边缘板等结构单元的保存状态将这些标本归为Somersault模式、Harrington模式及Henningsmoen模式,并对其形成过程进行简要讨论。E. guizhouensis蜕壳标本的保存模式常表现为活动颊与腹边缘板连接为一个整体从头甲中脱落后置于老壳之下或四周,头盖多与胸甲保持连接状态或轻微裂开。现有材料表明E. guizhouensis主要通过头部缝合线(面线及腹边缘线)的断开来完成蜕壳,由于在蜕壳过程中不同的运动方式而形成以Somersault模式、Harrington模式及Henningsmoen模式保存。文中通过对E.guizhouensis蜕壳标本的保存模式、蜕壳方式及蜕壳过程进行阐述,为褶颊虫类三叶虫的蜕壳模式及蜕壳过程研究提供重要依据。  相似文献   

6.
Alain Demonfaucon 《Geobios》1984,17(1):107-112
Biostratigraphic scale of conodonts established inthe germanic basin is found in Luxemburg. The repartition of associations allows to determine six zones which can be compared to those of neighbouring areas.  相似文献   

7.
贵州东部寒武系苗岭统乌溜阶凯里组中上部保存了大量褶颊虫类三叶虫Xingrenaspis xingrenensis蜕壳标本,为揭示这类三叶虫的蜕壳行为提供了良好的材料。对比分析X.xingrenensis 106块蜕壳标本后分为如下3种保存类型:类型Ⅰ(63块),轴背构造(头盖、胸甲及尾板连接保存),未见活动颊及头甲的腹部结构;类型Ⅱ(2块),胸尾保持连接状态,头甲自头胸结合处断开后向后翻转180°,活动颊及头部腹面结构缺失或压于胸甲之下;类型Ⅲ(41块),头盖及胸尾连接保存,活动颊脱开在虫体周围或压于胸甲之下。从这3种保存类型中发现X.xingrenensis蜕壳方式不仅有通过头部缝合线打开产生的前蜕壳口来进行,也存在由头胸结合处的断口来完成蜕壳行为。从埋藏学方面来看,因蜕壳而形成的独特外壳组合的保存必须在静水沉积环境中,大量X.xingrenensis蜕壳标本的发现为凯里生物群为原地(近原地)埋藏提供了关键的证据。  相似文献   

8.
Cantier  J. M.  Bastide  J. 《Plant and Soil》1986,94(2):153-161
Summary The catalytic effect of synthetic argilo-humic complexes on chemical transformation of propyzamide and analogs is shown. This chemical transformation is easier when the phenyl group is substituted by electro-donating substituents. An increase of complexe moisture increases the rate of degradation. These relations between degradation rates in argilo-humic complexes and soils are discussed.
  相似文献   

9.
10.
Ammonites diartianus d'Orbigny is a Vascocerasoof late Cenomanian (Sciponoceras gracile Zone) age, occuring in both Sarthe (France) and southern England. It is the earliest vascoceratid known from France, and its recognition is of great significance, lending support to recent suggestions that the classic Vascoceras gamai - mundaeChoffat group are of Upper Cenomanian age.  相似文献   

11.
    
The radiolarian zonation of the Izumi Group is revised for an integrated biostratigraphy across the Campanian/Maastrichtian boundary, together with the ammonite occurrence, fission track and magnetostratigraphic calibration of the acidic tuff key beds. The significance of direct correlation in the same sections, between macro- and micro-fossils (i.e. between relatively near-shore nektonic and turbiditic planktonic-fauna) is discussed in relation to the litho- and bio-facies of the Izumi group. Late Cretaceous paleoceanographic changes inferred from the studied radiolarian fauna represent a regional marker event for the chronostratigraphic correlation of continental shelf to turbidite deep-sea sequences, which accumulated on a mid latitudinal margin facing towards the NW paleo-Pacific. The proposed Campanian/Maastrichtian boundary is at the limit between Pachydiscus awajiensis and Nostoceras hetonaiense ammonite zones. This boundary corresponds to the radiolarian last occurrence of Amphipyndax pseudoconulus (= A. enesseffi), Archaeodictyomitra sliteri, Dictyomitra formosa, D. koslovae and Rhopalosyringium magnificum at the top of the Myllocercion acineton Assemblage Zone (uppermost Campanian), and the first occurrence of Clathrocyclas gravis and Dorcadospyris sp. A, at the base of the Maastrichtian C. gravis Assemblage Zone. The new data settle partly a chronostratigraphic discrepancy between radiolarian and ammonite zonations in the Izumi Group, which was pointed out previously by Ishida et al. (2010).  相似文献   

12.
Th. Cadet 《Plant Ecology》1974,29(2):121-130
Summary The high mountains of Reunion Island (Indian ocean) harbor an ericaceous vegetation dominated byPhilippia montana. After a brief survey of the chief ecological factors, the author describes the main plant communities. Their physiognomy, floristic structure and succession have a close relation with edaphic factors.
Zusammenfassung Das Gipfelgebiet der beiden vulkanischen Bergst?cke der Insel Reunion (Indischer Ozean) tr?gt eine Erikazeenvegetation, in welcherPhilippia montana als vorwiegende Art erscheint. Nach einer kurzen Untersuchung der bedeutendsten ?kologischen Faktoren definiert der Autor die Pflanzengesellschaften deren Physiognomie, Blütenstruktur und Entwicklung mit den edaphischen Faktoren eng zusammenh?ngen.

Pour le nomenclature de la plupart des espèces, voir les tableaux 3 et 4.  相似文献   

13.
In the studied area, on the southern slope(«Ossa-Morena Zone) of the Sierra Morena (Spain) the Silurian and earliest Devonian (Lochkovian = approximately Gedinnian) consist of about 130 m of black, argillaceous, largely euxinic graptolitic slates, which, by the intermezzo of the dark «Limestones with Orthoceras and Scyphocrinus (late Ludlow and Pridolian), are divided into two inequal units, namely the Lower and Upper Graptolitic Slates. The occurence of 21 Graptolite zones and horizons was established, starting off with the basal Llandovery (A. acuminatus zone) and ending up with the Upper Lochkovian (M. hercynicas zone). This condensed tripartite graptolitic sequence, both lithologically and faunally, compares closely with the typical development of the Palaeotethys, as known from Thuringia, Carnic Alps, Sardinia and Northwest Africa. Certain graptolite species and details of the graptolitic succession (for instance across the Wenlock-Ludlow junction) that were hitherto known only or essentially from Thuringia, are recognized also in southern Spain.  相似文献   

14.
2013年7月在广东南岭国家级自然保护区阳山县境内(24°48′39.5′′N,112°51′01.3′′E,海拔155 m)捕捉到4只雄性蝙蝠,体型小,前臂长34.1~34.7 mm,颅全长14.3~14.7 mm;体毛浓密,背毛毛基黑色,毛尖灰色,腹毛黑或棕色,毛尖奶油白,靠近肛门处腹毛浅灰色,些许白色;翼膜附着于跖部末端;后足特别延展,长度超过胫骨长之半;鉴定为长指鼠耳蝠[Myotis longipes(Dobson1873)]。同时,基于Cyt b基因序列(1 140 bp)构建的部分鼠耳蝠物种系统进化关系,进一步确认上述标本为长指鼠耳蝠,为广东省翼手目新纪录。该种蝙蝠在我国贵州、广西、重庆有分布记载,但标本和相关资料很少。本文给出了长指鼠耳蝠的外形和头骨特征测量数据,并与印度的标本进行了对比。长指鼠耳蝠的回声定位声波为调频型(FM),主频率为68.2 k Hz;此外,对其分类地位和分布状况进行了讨论。标本保存于广东省生物资源应用研究所。  相似文献   

15.
A.H. Munshi 《Aerobiologia》2000,16(3-4):449-452
Several grass pollens are important environmental bio-pollutants, causing various allergic disorders in susceptible persons. Therefore, it is essential to study the period and duration of the flowering of the plants growing in a particular region/area. For the area Srinagar (Kashmir Himalaya), a flowering calendar of grasses consisting of 57 species which fall under 35 genera has been compiled in order to provide an understanding of habit, period of pollen release and their dispersal from the flowers, pollen load in the atmosphere and the influence of meterological parameters. The main object of this research work is to provide an information regarding the frequency of grass pollen in atmosphere to the physicians, or medical practitioners. The maximum flowering period is recorded from July to September. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.
Paul Ellenberger 《Geobios》1976,9(6):769-787
A new ichnological genus, Cynodontipus species-type C. polythrix) has been created to define the unusual tract of a large but still unknown hairy Vertebrate of the Early to Middle Trias, Southern France. Horizon: just below the Chirotherium white sandstones slabs at Fozières (Hérault).This new type of footprint indicates that, as early as the Middle Trias, some Vertebrates were covered with an abundant protection of hair. A short systematic comparison is attempted with the last big Therapsids of that age, mainly the Cynodonts.  相似文献   

17.
Dirk Nolf  Henri Cappetta 《Geobios》1976,9(3):251-277
An important new collection of otoliths from theCalcaire Grossier of the Paris Basin, as well as a critical review of already published material is studied and reveals the presence of 56 species. Five of these are new: Muraenesox spatulus, Genus Synodontidarum intermedius, Genus Ophidiidarum spinosus, Chanda bohlkei and Mene sekharani. The assemblage is indicative of tropical to subtropical marine and neritic environment with solid bottom. Biogeographically, it shows affinities with the recent Indo-pacific fauna. The association of the sites at Fercourt and Château-Rouge is clearly different from the one found at the sites of Condé-en-Brie and Damery, as it is less littoral than the second association mentioned.  相似文献   

18.
Representatives of the Nautiloculina population of the Berriasian-Upper Albian Pyrenean upper platform series (Navarro-Languedocian and Catalonian Pyrenees) and Subalpine ranges (Vercors) have been collected and studied. We are led to distinguish two species: one of them, N. cretaceaPeybernes, is the largest of all known Nautiloculina; it does not seem to exist beyond the upper Bedoulian. The other, N. bronnimanni n. sp., occurs up to the top of the Upper Albian; it is distinguished from the former by its smaller size, its depressions at the level of axis of coiling, and its depressed sutures.  相似文献   

19.
Jacques Sornay 《Geobios》1978,11(4):505-515
Modern determinations are given for the Inocerams figured by E. Guéranger in his work «Album paléontologique du département de la Sarthe.The validity of I. angulatus d'Orb. and I. scalprum J. Böhm is discussed as well as the variability of I. virgatusSchlüter.  相似文献   

20.
    
《Médecine Nucléaire》2022,46(4):169-174
IntroductionWe applied the response to therapy reclassification system (RTRS) to evaluate the disease status after surgery and I-131 therapy in differentiated thyroid carcinoma (DTC) patients with nodular goiter (NG).Materials and methodsA total of 268 DTC complicated with NG patients who underwent the I-131 treatment and thyroidectomy between 2010 and 2018 were analyzed. The RTRS were classified into excellent (ER), indeterminate (IDR), biochemical incomplete (BIR) and structural incomplete response (SIR). Logistic regression analysis were performed to evaluate the relevant clinicopathologic and laboratory variables in the prediction of non-ER (IDR, BIR and SIR).ResultsIn the logistic analysis, gender (OR: 3.543, P = 0.01), lateral cervical lymph node metastases (N1b) (OR: 6.646, P = 0.005), pre-ablation stimulated thyroglobulin (Ps-Tg) (OR: 0.859, P = 0.000), and anti-Tg antibody (TgAb) (OR: 64.546, P = 0.000) were predictor of non-ER. The cut-off value of ps-Tg for predicting the ER was 19.98 ng/mL with a sensitivity of 92.6% and specificity of 83.2%. The non-ER rate of N1b group was significantly higher than the central cervical LNM (N1a) group.ConclusionFor patients with DTC complicated with NG, the cut-off value of ps-Tg for predicting the ER was 19.98 ng/mL. N1b patients showed inferior responses to I-131 therapy compared to N1a patients.  相似文献   

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