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1.
陕西,鄂西下寒武统西蒿坪段“瓶状微化石”再研究   总被引:1,自引:0,他引:1  
本文展示了陕西西乡和湖北房县下寒武统西蒿坪段中的三块棘状集合体标本,论证了西蒿坪段中的所谓瓶状微化石不是原生动物,而一类接近于开腔骨类Chancelloriids的多骨片后生动物化石。将过去在西蒿坪段中描述的14属38种“瓶状微化石”合并成1属1种,即Cambrothyra ampulliformis Qian et Zhang,1983和C.truncata (Duan),1986。  相似文献   

2.
苏皖象山群下部一些本内苏铁目化石的表皮构造研究   总被引:1,自引:0,他引:1  
报道象山群下部的本内苏铁植物5属6种:Tyrmiasusongensissp.nov.,Pterophylumsp.1,P.sp.2,Anomozamitesquadratussp.nov.,OtozamiteshsiangchiensisSze,Nilsoniopterisvitata(Brongn.)Florin,对其表皮构造进行了详细的描述。分布于苏皖沿江地区早中侏罗世的象山群,含有丰富的植物化石,但保存有炭质薄膜可资内部构造研究的标本尚属首次发现。  相似文献   

3.
吴纪华  孙希达 《四川动物》1996,15(3):98-99,117
本文报告长白山地区杜拉属蚯蚓一新种,长白山杜拉蚓Drawidachangbaishansissp.nov。模式标本保存存于杭州师范学院生物系。  相似文献   

4.
本文研究了中国奥姬小蜂属(Aulogymnus  Forster),该属在中国是首次发现。本文描述了 4个新种,A. elevatus sp. nov, A. hyalopterus  sp. nov, A 、insculptus sp. nov, A. longicalcar  sp. nov。所有模式标本保存于中国科学院动物研究所动物标本馆。  相似文献   

5.
记述原始锥石类中的一个新属种   总被引:4,自引:4,他引:0  
本文描述了我国四川峨嵋灯影组麦地坪段原始锥石类中的一个罕见的具有三个柱面的Emeiconulariatrigemmegen.etsp.nov.。并与具有四个柱面的Carinachitids和六个柱面的Hexangulaconularids进行了比较讨论。经扫描电镜观察,该属种壳体由二层组成。内层由棱柱状胶结物组成,外层由微粒状磷酸盐颗粒组成。它们被认为是经过改造了的原生磷酸盐质壳壁。  相似文献   

6.
王耀 《古生物学报》1996,35(6):702-713
描述了豆海百合类2属7种,它们是:Pisocrinus(P.)pilula,P.(G.)kosovensis,P.(G.)bohemicus,Pampisocrinusollula,P.Sphericus,以及Pisocrinus(G.)brevissp.nov.和Parapisocrinuspateriformissp.nov.;并首次发现了P.(G.)bohemicus萼杯内腔的内部钙质骨胳构造。同时,还就波希米亚豆海百合种内变异和豆海百合类的对称性进行了研究。  相似文献   

7.
本文记述采自广西壮族自治区的刺翼蚱科昆虫2新种,即广西镰蚱Falconiusguangxiensis,sp.n.和短背真角蚱Eucriotetixbrachynotus,sp.nov.。并对发现的龙州波蚱BolivaritetixlongzhouensisZhengetJiang雌性进行了描述。模式标本保存于陕西师范大学动物研究所。  相似文献   

8.
贵州台江早、中寒武世凯里组的Wiwaxia   总被引:2,自引:0,他引:2  
赵元龙  钱逸 《古生物学报》1994,33(3):359-366
首次报道产于我国贵州台江早、中寒武世凯里组的Wiwaxia骨片化石,讨论了Wiwaxiidae与Halkieriidae和Sachitidae不能归属于同一科,也不能将它与Siphogonuchitidae和Chancelloriidae归于同一纲、目,它的分类位置尚不能确定。通过对新种Wiwaxiataijiangensis的描述和讨论,指出了描述种产出的层位略低于北美的W.corrugataWalcott的时代,但处于不同生物地理区系的两个种的生活环境却基本相似。  相似文献   

9.
牙形石Parapachycladina peculiaris的表面微细构造研究及其启示   总被引:1,自引:0,他引:1  
Parapachycladina peculiaris表面微细构造最初是以分散保存的牙形石分子为研究对象,作者应用逻辑推理和数理统计方法重塑的器官,在分类上应属Prioniodinida目Ellisonidae科。该牙形石器官中的六种分子均具有一致的口面和反口面表面微细构造,这种一致的口面和反口面表面微细构造的发现,为重塑该器官提供了更加可信的、来自牙形石本身的生物学证据,同时表明牙形石的表面微细  相似文献   

10.
对产自吉林浑江大阳贫早奥陶世亮甲山组的大型粗壳内角石类进行系统进行,共描述2科3属37种和1个科属未定标本,其中1新属、3新种和2未定种。首次报道Piloceratidae科分子(Paracassinoceras dayangchaense gen.et sp.nov.)在东亚的首次发现。提出角石类内体管构造的4个类型。详细讨论Manchuroceras和Manchurceraidae科的地理分布  相似文献   

11.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

14.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

15.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

16.
17.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

18.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

19.
Nine blood group systems of goats were identified using 12 caprine reagents produced by absorption of alloimmune antisera. The caprine C blood group system, possibly homologous to the ovine C blood group system, was characterized by two reagents and shown to be controlled by three alleles,C 12,C 25, andC . A more complex blood group system of goats, designated G, was identified using three reagents and shown to be controlled by six codominant alleles (G 10.19.20,G 10.19,G 10.20,G 10,G 19,G 20) and a recessive allele (G ). A further seven one-factor two-allelic systems were identified by seven reagents. The nine genetic systems provided exclusion probabilities of 0.479, 0.492, 0.548, and 0.572 in Australian Angora, Dairy, Cashmere, and Texan Angora goat breeds, respectively. This work was supported by a grant from the Australian Stud Book, Alison Road, Randwick, New South Wales 2031, Australia.  相似文献   

20.
《Ibis》1894,36(3):447-460
  相似文献   

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