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1.
在滇西保山上新统首次发现了黄背栎(Quercuspannosa)压型化石,并分析了角质层构造。其特征主要为:上表皮无气孔器,表皮细胞为不规则形五边形,垂周壁微弯曲,脉络为网格状,无毛基;下表皮具环列型气孔器,表皮细胞为不规则形五边形,垂周壁微弯曲,脉络为五边形的网格状,具毛基,毛的根部由多细胞组成,毛基部的细胞特化成辐射状。利用现存最近亲缘种(NLRspecies)原理,并比较化石和现生Q.pannosa角质层特征,推断上新世Q.pannosa在羊邑生长的古环境比现生Q.pannosa生存的冷湿气候相对干旱,且化石Q.pannosa为近原地埋藏。  相似文献   

2.
中国大蒜芥属(十字花科)叶表皮微形态学研究   总被引:1,自引:0,他引:1  
利用光学显微镜观察了中国十字花科大蒜芥属9种1变种植物的叶表皮形态。结果表明:中国大蒜芥属植物叶上表皮细胞通常为多边形,垂周壁平直或弓形,少有稍浅波状,叶下表皮细胞为不规则形,垂周壁波状或深波状;气孔器类型均以不等细胞型为主,少有无规则型,偶有平列型。依据叶表皮特征,可将中国大蒜芥属划分为三种类型: (1)叶上表皮无气孔分布或偶见; (2)叶上表皮气孔常明显几个聚成一簇或排成短列,气孔密度小于叶下表皮; (3)叶上表皮气孔比较均匀分布,气孔密度与叶下表皮近相似。  相似文献   

3.
为了解柿属(Diospyros)植物的叶表皮特征,在光学显微镜下观察了46种2变种植物的叶表皮微形态特征,并进行了主成分分析。结果表明,柿属植物的叶表皮微形态可分为2组:A组的表皮细胞为不规则形,垂周壁浅波状或深波状;B组的表皮细胞为多边形,垂周壁平直或弓形。气孔全部位于下表皮,以无规则型为主,但同时有辐射型、环列型和十字型气孔存在。大多数种具有表皮毛,表皮毛有非腺毛和头状腺毛的区别。柿属植物的叶表皮微形态特征类型多样,能够为部分类群的分类提供较好的形态学证据。  相似文献   

4.
陈旭波  刘全儒  李艳 《植物研究》2010,30(5):527-536
采用光学显微镜,对华北地区分布的繁缕属植物16种2变种,其它4属4种植物的叶表皮微形态进行了观察。结果表明:繁缕属植物叶片的下表皮均存在气孔器,而上表皮仅少数种类缺乏气孔器。气孔器类型比较多样,有不等细胞型、无规则型、无规则四细胞型;表皮细胞主要为不规则型,垂周壁从平直、弓形、浅波状、波状、到深波状;上表皮气孔指数在5.23~31.65之间;下表皮气孔指数在10.02~29.44。叶表皮被毛或无,毛被分为星状毛、腺柔毛、柔毛、绢毛。该研究说明叶表皮的微形态特征在种间差异明显,可以为分种及属间亲缘关系的探讨提供依据,但是对组的划分存在一定的局限性。  相似文献   

5.
中国蓼属头状蓼组植物叶表皮微形态及其分类学意义   总被引:2,自引:0,他引:2  
采用光学显微镜对中国蓼属头状蓼组17种7变种植物的叶片下表皮微形态进行了观察研究,结果表明,其叶片下表皮微形态特征分为4种类型:(1)气孔器类型为无规则型,表皮细胞不规则形,垂周壁波状或深波状;(2)非典型不等型,偶有无规则型,表皮细胞多边形或不规则形,垂周壁弓形、波状或深波状;(3)平列型,表皮细胞不规则形,垂周壁深波状;(4)平列型兼有非典型不等型,表皮细胞不规则形,垂周壁波状。根据其叶片下表皮气孔器类型,结合该组植物形态、习性等特征,将中国蓼属头状蓼组植物划分为4个系,即掌裂叶系、多年生系、蓼子草系以及一年生直立系。  相似文献   

6.
土圞儿属和旋花豆属(豆科)的叶表皮特征及其系统学意义   总被引:1,自引:0,他引:1  
应用光学显微镜和扫描电子显微镜观察了豆科Leguminosae土圞儿属Apios和旋花豆属Cochlianthus植物的叶表皮特征。在光学显微镜下,大多数种类的叶表皮细胞形状(表面观)为不规则型,垂周壁式样为浅波状或波状,只有一个种——和Apios gracillima Dunn叶表皮细胞为多边形,垂周壁式样为较平直。在扫描电子显微镜下,多数种类的叶片蜡质纹饰通常为片状或颗粒状,一些种叶表皮未见蜡质纹饰;气孔器外拱盖内缘通常为浅波状或近平滑。在这两个属内,上述叶表皮特征在物种内较稳定,因此对于解决属内种间和属间关系有一定的系统学意义。本研究得出以下结论:(1)A.gracillima叶的上表皮细胞为多边形,垂周壁平直或弧形,A.delavayi Franch.叶的上表皮细胞为不规则形,垂周壁波状,二者存在明显差异,因此A.gracillima应处理为一独立的种,而不是A.delavayi下的一个变种;(2)A.priceana B.L.Rob.在叶表皮细胞形状、垂周壁式样、气孔器类型和蜡质纹饰形态等方面与土圞儿属中其他种不存在显著区别,因此土圞儿属内两个亚属的划分是不合理的;(3)土圞儿属多为5或7小叶,无毛或近无毛,叶表皮细胞垂周壁波状或近平直,而旋花豆属3小叶,密被柔毛,叶表皮细胞垂周壁浅波状,本文支持它们为两个独立的属的分类处理。  相似文献   

7.
山东广义苦荬菜属(菊科)叶表皮微形态的研究   总被引:1,自引:0,他引:1  
高召兰  李法曾   《广西植物》2007,27(3):435-439
对山东广义苦荬菜属植物叶表皮微形态进行了光镜下的观察研究。结果表明:山东广义苦荬菜属9种植物叶表皮微形态可分为四种类型:(1)小苦荬型:上、下表皮均有气孔器,气孔器为不规则型,偶有非典型不等型,上、下表皮细胞为不规则形,垂周壁波状;(2)黄瓜菜型:上表皮无气孔器,下表皮气孔器为不规则型,偶有非典型不等型,上、下表皮细胞为不规则形,垂周壁深波状;(3)沙苦荬型:上、下表皮均有气孔器,气孔器为不规则型,偶有非典型不等型,上、下表皮细胞为多边形,垂周壁平直、弓形;(4)苦荬菜型:上、下表皮均有气孔器,气孔器为不规则型,偶有非典型不等型,上表皮细胞为不规则形,垂周壁波状,下表皮细胞为多边形,垂周壁弓形;与中国植物志把广义苦荬菜属划分为4个属的意见相一致。  相似文献   

8.
曾妮  张建茹  常朝阳 《广西植物》2017,37(2):169-185
应用光学显微镜和电子显微镜,对30种中国蔷薇属植物叶表皮的微形态特征进行了观察。结果表明:叶表皮细胞一般为多边形或不规则形,垂周壁平直、平直弓状、波状、浅波状和深波状式样;该属植物的叶表皮细胞大小种间差异较大,总体来看上表皮几乎全为多边形细胞,且上表皮细胞比下表皮细胞略大;在扫描电镜下观察,大部分细胞的平周壁下陷,仅部分细胞的平周壁突起;叶表皮角质层纹饰多样、即使同一个种的上下表皮细胞角质层纹饰微形态特征也有差异;大多植物叶片表面具柔毛,均为单毛,有长柔毛和短柔毛,大部分种类的柔毛基部无特化,其基部由普通的表皮细胞围绕着,少部分种类的柔毛基部由几个特化的辐射状细胞围绕着,少数植物无毛;有些植物叶表面或叶脉上还分布有腺毛;除了单叶蔷薇亚属的小蘗叶蔷薇1个种的上下表皮均分布有气孔器外,其余蔷薇亚属的29种植物的气孔器均分布在下表皮,形状为椭圆形、宽椭圆形和长椭圆形三种,气孔器类型有无规则型、不规则四细胞型、对位四细胞型、环列型和辐射型;气孔器外拱盖内缘近平滑或呈深浅不同的波状、气孔器外拱盖纹饰光滑或粗糙,大多植物气孔器的保卫细胞两级T型加厚;另外,只有小蘗叶蔷薇的气孔器具双层外拱盖且仅上表皮被毛等特征也说明了其在演化上的特殊地位,蔷薇属植物叶表皮的这些微形态特征,在属内各组间无明确的规律性,但可为探讨该属种间的分类学及亲缘关系提供依据。  相似文献   

9.
为了解山药种质资源间的相互关系、消除品种混乱,为选育优良品种提供理论依据,对33份山药种质资源的叶下表皮微形态进行显微观察。结果表明,山药叶下表皮细胞形状均为不规则形,表皮细胞大小变化显著,垂周壁类型有平直、微波状弯曲、波状弯曲及深波状弯曲。气孔器类型均为不定型,形状有椭圆形及长椭圆形;气孔器大小和气孔指数变化较稳定,而气孔器密度在种质资源间差异较大。提出的"细胞形状系数"是指某一细胞平周壁的表面积与周长同该细胞垂周壁相等的圆的面积之百分比,可定量地反映细胞形状变异程度,其值为19.31%~70.60%。根据山药叶下表皮微形态特征可将33份山药种质资源分成4个类型。  相似文献   

10.
对变豆菜属(Sanicula L.)6种13个居群植物的叶表皮特征进行光学显微观察,并测定了相应的数量指标。结果表明,变豆菜属植物叶表皮形态较为一致:上表皮几乎全为多边形,垂周壁平直或弓形弯曲;下表皮多为不规则形,垂周壁浅波状、波状至深波状;气孔散生,均为不等型。但表皮细胞垂周壁式样、气孔长短轴之比等细微特征在种间存在差异,可以区分种类。因此,叶表皮特征对于变豆菜属种类的划分和亲缘关系的确定具有一定的分类学意义。  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.
15.
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   

16.
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   

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.
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   

19.
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   

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

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