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1.
传统观念认为GSPD组合始于中二叠世孔谷期,据新疆等地资料证实此类组合的出现要早得多。准噶尔盆地在Profosulinella-Pseudostaffella带之下和相当层位的晚石炭世早期地层中存在两个孢粉组合,即(1)早巴什基尔期巴塔玛依内山组的Remysporites^*uaricus-Striatole-bachittes junggarensis组合(Pro-GSPD)和(2)中晚巴什基尔  相似文献   

2.
部分裸子植物叶片总蛋白分析   总被引:1,自引:0,他引:1  
王艇  苏应娟  黄超  朱建明   《广西植物》1999,19(4):367-372
采用SDS- PAGE 技术, 分析了红豆杉科(Taxaceae) 植物南方红豆杉( Taxus chinensisvar- mairei (Lemee et Levl-) Cheng et L-K-Fu) 、穗花杉( Amentotaxus argotaenia (Hance) Pil ger) 、云南穗花杉( A- yunnanensis Li) 、白豆杉( Pseudotaxuschienii(Cheng) Cheng) 以及三尖杉科(Cephalotaxaceae) 、植物三尖杉( Cephalotaxus fortunei Hook-f-) 、粗榧( C-sinensis (Rehd-etWils-) Li) 、海南粗榧( C-hainanensis Li) 、篦子三尖杉( C-oliveri Mast-) 和罗汉松科(Podocarpaceae) 、植 物罗汉松 ( Podocarpus macrophyllus ( Thunb- ) D-Don) 、鸡毛 松( P-imbricatus Bl-) 、竹柏( P- nagi(Thunb-) Zoll) 、陆均松( Dacrydium pierrei Hickel) 共12 种植物的叶片蛋白, 在蛋白质水平上采用  相似文献   

3.
中国新第三纪中—小型猿类化石及其意义   总被引:1,自引:0,他引:1  
潘悦容 《人类学学报》1998,17(4):283-292
中国新第三纪中-小型猿类主要有早中新世江苏泗洪的双沟醉猿(Dionysopithecus shuan-gouensis Li,1978)和江淮宽齿猿(Platodntopithecus jianghuaiensis Gu and Lin,1983);中中新世宁夏同心的占祥上猿,(Pliopithecus zhanziangi Harrison,Delson and Guan,1991)和晚中新世云  相似文献   

4.
Zhao XY  Jiang ZY  Peng JZ 《生理学报》2000,52(6):473-478
在麻醉大鼠侧脑室注射左旋一叶Qiu碱(L-Sec),记录动脉血压(AP)、心率(HR)及肾交感神经放电(RSND),观察前脑室周系统GABA能紧张性活动改变引起的心血管效应。结果如下:(1)L-Sec可引起RSND增加、AP升高和HR加快,并呈一定剂量-效应关系;但L-S盈余 于bicuculline(Bic)。(2)L-Sec既能拮抗muscimol(Mus),又能拮抗baclofen(Bac)  相似文献   

5.
海南岛东部近海新第三纪孢粉植物群   总被引:3,自引:0,他引:3  
根据BD23-1-1井与孢子花粉共生的海相浮游有孔虫和钙质超微化石,论述了中国海南岛东部近海新第三纪各个时期的孢粉植物群特征。建立了4个孢粉组合,它们是:1.Quercoidites-Cupuliferoipolenites-Florshuetzia-Dicolpopolis组合(早中新世晚期);2.Dicolpopolis-Extra-punctatosporites-Taxodiaceaepolenites组合(中中新世早期);3.Abietineaepolenites-Polypodi-aceaesporites-Liquidambarpolenites组合(中中新世晚期至晚中新世);4.Abietineaepolenites-Persicarioipolis组合(晚中新世晚期至早上新世)。孢粉植物群反映了海南岛东部近海新第三纪的气候基本上一直比较温暖湿润,并且逐渐降温的历程。  相似文献   

6.
用Kunkel突变法,将单链尿激酶型纤溶酶原激活剂(scu-PA)cDNA基因中编码Pro155—Lys158的片段定点突变,并将此突变的scu-PA(tscu-PA)的cDNA克隆到表达载体pCM-β-neo中,与pCM-dhfr共转染CHO/DHFR-细胞.获得的稳定表达株在无血清培养基中24h的表达量为620IU/106细胞.经锌离子螯合Sepharose亲和层析得到tscu-PA纯品.SDS-PAGE显示tscu-PA分子量为53kD左右,与预期的结果相符.tscu-PA是由凝血酶激活而不是由纤溶酶激活,但激活后也能转变为双链分子(tcu-PA).tscu-PA仍保持了scu-PA的血纤维蛋白亲和性.酶动力学研究表明,激活后的tscu-PA水解S2444的Km和Kcat值与高分子量尿激酶(HUK)相似.体外溶栓实验结果表明,tscu-PA可以选择性地溶解富含凝血酶的血凝块,对贫凝血酶的血凝块作用不大  相似文献   

7.
苏云金杆菌超氧化物歧化酶的纯化和性质研究   总被引:3,自引:0,他引:3       下载免费PDF全文
苏云金杆菌(Bacillus thuringiensis)9165超氧化物歧化酶(SOD),经硫酸铵分级沉淀、SephadexF-100凝胶过滤及非变性凝胶电泳(PAGE)三步纯化,纯酶比活力为4388u/mg,属Mn-SOD,分子量为47.9ku,由二个亚基组成,含19种氨基酸。  相似文献   

8.
南京龙潭地区五通组孢子组合及其地质时代   总被引:12,自引:4,他引:8  
南京龙潭地区五通组共产小孢子53属136种(含12新种),可划分4个孢子组合,即Aneurosporaasthenolabrata-Radiizonateslongtanensis(AL)组合,Retusotriletes-Cymbosporites(RC)组合,Knoxisporites-Densosporites(KD)组合与Leiotriletescrassus-Laevigatosporitesvulgaris(CV)组合。详细分析某些已知种的垂直分布与组合对比表明:龙潭五通组除包含晚泥盆世沉积外,还包含部分早石炭世的沉积,泥盆-石炭系界线置于RC与KD组合之间,即擂鼓台段下一中部与中一上部之间较适合。此结论与相关的植物与鱼化石的时代基本一致。  相似文献   

9.
塔里木盆地北缘侏罗纪孢粉组合   总被引:11,自引:6,他引:11  
本文系统地研究了塔里木盆地北缘侏罗纪的孢子花粉。共发现孢粉化石52属90种,以及藻类化石2属2种。建立侏罗纪的孢粉组合序列如下:(1)Disacciatrileti-Cyathidites组合(早侏罗世早期阿合组),(2)Cyathidites-Cibotiumspora-Disacciatrileti组合(早侏罗世晚期阳霞组),(3)Cyathidites-Neoraistrickia-Disacciatrileti组合(中侏罗世早期克孜勒努尔组),(4)Cyathidites-Clasopolis组合(中侏罗世晚期恰克马克组)。根据孢粉组合特征讨论了地质时代,同时探讨了古植被和古气候的意义。  相似文献   

10.
心叶三脉蕨(新属,新组合)及大羽羊齿类的分类位置   总被引:1,自引:0,他引:1  
报道大羽羊齿类中的一真蕨植物新属和新组合。标本采自福建将乐县晚古生代的“龙潭组”。曾以脉序介于重网状和单网状之间,鉴定为心叶单网羊齿(新种)(Gigantonoclea cardio-phylla Zhu etGeng)。重新研究后,根据其三出脉和不完全的重网状脉式,又发现了其孢子囊群,从营养叶看,可归入大羽羊齿类,介于大羽羊齿和单网羊齿之间,从孢子囊群看,则肯定是真蕨,重新命名为心叶三脉蕨(新属、新组合)[Trinerviopteris cardiophylla (Zhu et Geng)Zhu gen.et com b.nov.]。与之同时发现的其它植物有:Sphenophyllum em arginatum 、Bow -m anites laxus、Lobatannularia lingulata、Chansitheca palaeosilvana、Ch. cf. kidstonii、Pecopteris anderssonii、P.echinata、P.? taiyuanensis、P.unita、Danaeites m irabilis、Fascipterisdensata、Cladophlebis ? perm ica、C  相似文献   

11.
The results of a palynological analysis of the sedimentary sequence of Borehole RCH-151, Chuperbhita Coalfield, Rajmahal Basin, Bihar are presented here. The borehole penetrated the Rajmahal Formation (comprising two traps sandwiching an intertrappean bed), the thinly represented Dubrajpur Formation and in its lower part, the Coal Measures. The coal-bearing interval is associated with Scheuringipollenites barakarensis, Faunipollenites varius, Densipollenites indicus, Gondisporites raniganjensis and Densipollenites magnicorpus Assemblage Zones. The presence of these biostratigraphic units indicates correlation with the Barakar Formation (Early Permian) and the Barren Measures and Raniganj Formations (both Late Permian). This is the first record, in the Chuperbhita Coalfield, of Late Permian strata, which appear to represent a condensed sequence. Prior to the present study, the Permian succession was thought to have been associated entirely with the Barakar Formation. The overlying Dubrajpur Formation yielded a distinct spore-pollen assemblage (in association with the first report of dinoflagellate, Phallocysta), which is assigned to the newly identified Callialasporites turbatus palynozone of latest Early to early Middle Jurassic age. The diverse spore-pollen flora of the intertrappean bed (Rajmahal Formation) incorporates several age marker taxa, viz. Undulatisporites, Leptolepidites, Klukisporites, Ruffordiaspora, and Coptospora. The assemblages from intertrappean beds are correlated with the Ruffordiaspora australiensis palynozone of Australia. Thus the palynodating indicates Permian, latest Early to early Mid-Jurassic and Early Cretaceous age for the strata studied. This is the first record of definite Jurassic microfossils from the non-marine sequence of Rajmahal Basin, India.  相似文献   

12.
13.
鲁西地区二叠系上、下石盒子组孢粉组合及其分界   总被引:4,自引:0,他引:4  
为解决鲁西地区上、下石盒子组分界问题,在相关地层共采集处理孢粉样品100多块,经系统研究建立本区上、下石盒子组两个孢粉组合,自下而上为:1)Sinulatisporites sinensis-Patellisporites meishanensis组合;2)Anticapipollis reticor pus-Macrotorispora gigantea组合。根据所建立的孢粉组合特征,经与华北各地二叠系孢粉组合广泛对比,进一步阐述各孢粉组合的地质时代,并为本区二叠系上、下石盒子组的分界提出了较为可靠的意见。该界线与区内中期华夏植物群晚期和晚期华夏植物群早期植物群界线基本一致。  相似文献   

14.
The Middle Jurassic palynoflora from the two wells of PUl and CN1 of Turpan-Shanshan area in Xinjiang consists of 97 species of fossil spores and pollen grains referred to 45 genera, of which 2 species are newly described. Three palynological assemblages including: 1) Cyathidites-Cycadopites-Quadraeculina (CCQ), 2) Cyathidites-Classopollis-Picites (CCP) and 3 ) Granu-latisporites-Classopollis-Podocarpidites (GCP) assemblages are established in the Xishanyao, Sanjianfang and Qiketai Formations, respectively. Comparisons have been made between these assemblages with those of the adjacent regions in Xinjiang and other domestic areas and at abroad. The geological age of the CCQ assemblage is suggested to be at early Middle Jurassic (corresponding to Aalenian to Bajocian age); while the CCP and GCP assemblages are considered to be at late Middle Jurassic (corresponding to early to late Bathonian age, respectively).  相似文献   

15.
新疆吐鲁番—鄯善地区中侏罗世孢粉组合   总被引:7,自引:0,他引:7  
研究新疆吐鲁番鄯善地区葡1井和草南1井中侏罗世孢子花粉化石45属97种,包括2个新种。建立西山窑组、三间房组和七克台组共3个孢粉组合,其地质时代相当于中侏罗世早期和晚期。  相似文献   

16.
通过对山东青东凹陷西部古近纪地层孢粉研究,共建立4个孢粉组合:Ⅰ.Ephedripites-Inaperturopollenites-Ulmipollenites minor,Ⅱ.Pinaceae-Ulmoideipites tricostatus-Taxodiaceaepollenites,Ⅲ.QuercoiditeshenriciTaxodiaceaepollenites hiatus,Ⅳ.Alnipollenites-Juglanspollenites-Polypodiaceaes porites。根据与渤海湾地区的孢粉资料对比,确定4个组合的时代分别为早始新世晚期—中始新世早期、中始新世早—中期、中始新世中—晚期、中始新世晚期—晚始新世。该区古近纪植被类型由落叶、阔叶和灌木混交林逐步转变为落叶、常绿阔叶和针叶混交林,古气候经历了干热的亚热带气候到湿热的亚热带气候再到亚热带型温暖气候的变化。沙四段上部到沙三段下部沉积时期是研究区烃源岩最为发育时期。  相似文献   

17.
The ecological competition between brachiopods and bivalves is analysed by means of a quantitative palaeoecologic method applied on four assemblages located within a short stratigraphic interval, approximately 2 m thick, in the lower Tesero Member of the Werfen Formation (in the Southern Alps). The assemblages originate from the Tesero, Bulla and Sass de Putia sections. The analysed stratigraphic interval, uppermost Changhsingian in age, is located between the early and heaviest phase of the end-Permian mass extinction, which occurred across the Bellerophon/Werfen formational boundary (Event Boundary), and the Permian/Triassic boundary (Chronological Boundary), when nearly all the Permian stenotopic holdovers disappeared.These assemblages are characterised by small sized skeletons (“Lilliput effect”), which represent an adaptive survival strategy in stressed and harsh habitats resulting from the climatic and palaeoceanographic changes connected with the mass extinction. The Tesero assemblages are dominated by rhynchonelliform brachiopod Orbicoelia (bed CNT10) or Streptorhynchus (bed CNT11A), which were mostly attached at the top of shallow microbialitic mounds. These assemblages are again dominated by Permian stenotopic taxa and show a Palaeozoic structure. The Tesero habitat, which again permitted the survival of brachiopods, represented one of the last refuges in the western Tethys. On the contrary, the Bulla (BU9-10) and Sass de Putia (wPK13A) assemblages are bivalve-dominated, and thus show an ecologic structure typical of Early Triassic post-extinction marine benthic communities or Palaeozoic stressed marine communities. The bivalve-dominated assemblages proliferated in prevailing muddy siliciclastic substrates, with brief episodes of microbial algal growth. The most important environmental limiting factors and leading causes of end-Permian mass extinction are discussed in terms of palaeoautecologic and palaeosynecologic analysis.The different taxonomic composition and ecologic structure of the assemblages is related to palaeogeography, including water depth and connections with the open sea. The brachiopod-dominated assemblage, exclusive of the Tesero section, proliferated in microbial carbonate habitats in near-shore environments. The bivalve-dominated assemblages, which were more widespread than the brachiopod assemblages in the Dolomites and also occurred in other western Tethys localities, occur in more open and deeper marine environments. In the western Tethys margins, the local distribution of mixed faunas suggests that the extinction of Permian stenotopic taxa was caused by the onset of poisonous water on the shelves originating from deep marine environments.This extinction pattern appears to be a regional phenomenon and does not seem be applicable on a global scale. The extinction events were controlled by a complex network of interactive factors and the survival of faunal elements was probably stochastic.  相似文献   

18.
The objective of the present work is to palynologically date the samples collected from Jharia Coalfield. The samples have been collected from an outcrop section exposed across the Damodar river near NH 32 enroute from Bokaro to Dhanbad (23° 43′06.93″N and 86° 12′06.90″E) near Jharia Coalfield of Damodar Basin. Palynological analysis of the samples has revealed that the palynomorph assemblage is characterized by high incidence of Densipollenites spp. in association with dominance of striate bisaccates chiefly Striatopodocarpites spp. and Faunipollenites spp. The other stratigraphically significant taxa recorded in the section are Guttulapollenites hannonicus, Klausipollenites schaubergeri, Alisporites spp. Falcisporites spp. and Lunatisporites spp. On the basis of the palynocomposition the section has been assigned a latest Permian age. Age determination for the section has been inferred by comparison with coeval assemblages from previous Gondwana studies from India and across Gondwana which were compared to the biostratigraphically dated palynological records from Australia (oldest APP6 Zone) as it is one of the few areas in Gondwana where the palynological records have been calibrated against adequately dated marine invertebrate zones. However, comparison with the westernmost portion of Gondwana was difficult due to its mid latitudinal position (c. 20°S) during the Lopingian (late Permian) which lead to an early transition from coal-bearing strata to red-bed and evaporitic deposits in some parts.  相似文献   

19.
20.
The classic leaf fossil floras from the Cretaceous of the Lusitanian Basin, Portugal, which were first described more than one hundred years ago, have played an important role in the development of ideas on the early evolution of angiosperms. Insights into the nature of vegetational change in the Lusitanian Basin through the Cretaceous have also come from studies of fossil pollen and spores, but the discovery of a series of mesofossil floras containing well-preserved angiosperm reproductive structures has provided a new basis for understanding the systematic relationships and biology of angiosperms at several stratigraphic levels through the Cretaceous. In the earliest mesofossil floras from the Torres Vedras locality, which are of probable Late Barremian-Early Aptian age, angiosperms are surprisingly diverse with about 50 different taxa. In slightly later mesofossil floras, which are of probable Late Aptian-Early Albian age, the diversity of angiosperms is still more substantial with more than hundred different kinds of angiosperm reproductive structures recognized from the Famalicão locality alone. However, this early diversity is largely among angiosperm lineages that produced monoaperturate pollen (e.g., Chloranthaceae, Nymphaeales) and early diverging monocots (Alismatales). Eudicots are rare in these Early Cretaceous mesofossil floras, but already by the Late Cenomanian the vegetation of the western Iberian Peninsula is dominated by angiosperms belonging to various groups of core eudicots. The Normapolles complex is a particularly conspicuous element in both mesofossil floras and in palynological assemblages. In the Late Cretaceous mesofossil floras from Esgueira and Mira, which are of Campanian-Maastrichtian age, core eudicots are also floristically dominant and flowers show great organisational similarity to fossil flowers from other Late Cretaceous floras described from other localities in Asia, Europe and North America.  相似文献   

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