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1.
延胡索亚属(Capnites DC)是紫堇属中较进化的一群,不少种类有药用价值。约57种,中国有17种,3变种,10变型。  相似文献   

2.
中国榕属榕亚属植物的系统发育初探   总被引:1,自引:0,他引:1  
对分布于中国的榕亚属植物的15个种和2个变种(分别代表榕亚属的3个组)的nrDNA的ITS序列和系统发育关系进行分析。结果表明,榕亚属是非单系起源,其中榕组构成了一个独立的单系群,与无花果亚属有较近的亲缘关系,而与榕亚属其它组间并未表现出近缘关系。榕亚属的其它5个组构成一单系群并得到中度的支持率。来自中国的种类分别聚在相应的组内。但环纹榕组被分成2个单支,其中来自中国的大叶水榕(F.glaberrima)和环纹榕(F.annulata)构成一个分支,二者表现较近的亲缘关系。榕亚属的亚洲特有组印度榕组在ITS树中聚在环纹榕组的另一个分支中,但它与此组其它种的亲缘关系并不清楚。  相似文献   

3.
苔草属复序苔草亚属植物果皮的扫描电镜观察   总被引:4,自引:1,他引:3  
张树仁  戴伦凯  梁松筠   《广西植物》2000,20(2):185-188+204
应用扫描电子显微镜 ,观察了 15种苔草属复序苔草亚属植物果皮的微形态特征。结果表明 ,复序苔草亚属植物果皮的微形态性状多种多样 ,可以为系统学研究提供较丰富的信息 ;并且在所观察的种类中 ,果皮的微形态特征在种内很稳定 ,种间存在不同程度的差异 ,某些近缘种也可表现出一定的相似性。因此 ,上述特征可以做为探讨种之间的分类及亲缘关系的参考。  相似文献   

4.
对中国堇菜属美丽堇菜亚属植物进行了系统学修订,确认中国堇菜属美丽堇菜亚属植物共有6种,列出分种检索表,对《中国植物志》51卷中未记载的3种进行了详细的描述,并对塔城堇菜、深紫堇菜及隐距堇菜进行了绘图。  相似文献   

5.
已知世界杜鹃属(Rhododendron)植物约967种(种下分类等级未计算在内)。本文基于植物区系学的观点,讨论了属内8个亚属:常绿杜鹃亚属、杜鹃亚属、马银花亚属、映山红亚属、羊踯躅亚属、云间杜鹃亚属、纯白杜鹃亚属、异蕊杜鹃亚属的系统位置、分布式样。分析了系统发育和地理分布上的时间、空间关系。认为常绿杜鹃亚属和杜鹃亚属是在本属植物起源后的早期阶段就沿不同途径迁徙、繁衍的两个演化枝。自第三纪以来,它们的性状发展多样,种系高度分化。在现存类群中最具原始性状的亚属是常绿杜鹃亚属,这个亚属的云锦杜鹃亚组Subsect.Fortunea,耳叶杜鹃亚组Subsect.Auriculata 保持较多原始性状。种的分布遍及欧洲、北美洲、亚洲、大洋洲(有1种),东亚种类最多,马来西亚次之。中国-喜马拉雅地区既是多度中心又是多样化中心,马来西亚仅是多度中心。大多数种为地方特有性分布,特有现象十分突出,东亚和马来西亚的特有种共约862种,占种总数的89%以上中国有6个亚属(Candidastrum,Mumeazalea不产)约562种,其中特有种约405种。分析第三纪的化石记录,杜鹃属在全球分布的时间、地点,杜鹃属保持原始或古老性状的类群的现代适生地,认为中国西南至中国中部最有可能是杜鹃属植物的起源地,始祖类群起源的时间会是在晚白垩纪至早第三纪。讨论了杜鹃属在第三纪至第四纪向北半球北部的传布,向亚洲西南、亚洲东南和向东亚的传布以及向大洋洲的传布。从杜鹃属在全球传布的现象和途径,看来现代分布格局形成的原因取决于三方面的因素:时间和窨历史对植物繁衍、传播有着重要制约作用,并受制于植物种系自身具有的遗传性和对环境强烈变化的反应能力。  相似文献   

6.
大吴风草属、假橐吾属花粉表面纹饰及其分类学意义   总被引:1,自引:0,他引:1  
观察了千里光族款冬亚族中大吴风草属,假橐吾属及其相关类群5属共8种植物在扫描电镜下的花粉性状,所有种类的花粉外壁均为刺状纹饰,但在刺的长短,刺部是否膨大、刺基膨大上的纹饰以及刺基之间的纹饰等方面存在差别,大吴风草的花粉外壁性状不同于橐吾属,从而不支持它与后者有较近亲缘关系的观点它与花粉超薄结构同为“向日葵型”的多榔菊属的花粉外壁性状也不相同,假橐吾属不同于橐吾属和垂头菊属的花粉外壁性状,研究结果支持本单种属的成立。  相似文献   

7.
中国紫堇属大叶紫堇组的分类与分布   总被引:4,自引:2,他引:2  
本文叙述大叶紫堇组在紫堇属(Corydalis)中的系统位置以及其分布区的原始性,同时记载了隶属于5个系的23种9变种和1变型,其中有4个新系,7个新种和7个新变种。  相似文献   

8.
对栎属青冈亚属17个种及炭栎花粉形态进行扫描电镜观察。结果表明:青冈亚属和炭栎花粉均为三拟孔沟,球形至长球形,(15~28.0)μm×(15.0~25.6)μm。花粉外壁纹饰可划分为3种:(1)蠕虫状(包括皱波状)、(2)聚合颗粒状、(3)棒状或小刺状。各纹饰在组间镶嵌分布。棒状及小刺状纹饰为栎属花粉较为原始式样,并为青冈亚属与高山栎组及部分巴东组(sect.Cerris)共有,推测其间具有较其它栎类更为接近的亲缘关系,可能为广义栎属中较为基础的类群,而与栎亚属sect.Quercuss.s.,Lobatae和Protobalanus关系较远。花粉形态对广义栎属系统分类价值仅适用于较高分类阶元。  相似文献   

9.
本文取中国乌头属50种(含变种)植物,选取形态学性状46个、化学性状8个、组织学性状5个、生态学性状1个,运用数量分类方法,对该属进行属下等级的分类研究。根据数学分析结果,确定了树系图中变种、种、系、亚属的分级界线,并在聚类分析的基础上,进一步探讨了各等级类群的划分。  相似文献   

10.
青冈亚属植物的地理分布   总被引:5,自引:0,他引:5  
对壳斗科青冈亚属(Quercus subg.Cyclobalanopsis)植物分布区内各地区的分布作了分析和统计。通过分析,认为中国南部、西南部和中南半岛北部,即印度支那植物地区,是青冈亚属植物地理分布的分布区中心。基于其形态、现代分布和地史资料,马来西亚地区分布有许多性状较原始的类群,是青冈亚属原始类的保存中心。青冈亚属植物中有许多地区 特有种,它们的分布区很狭窄,集中分布在加里曼丹、台湾、海南和云南东部部,其产生的原因主要是地理隔离,如海峡、高山等,以及气候和地史的复杂性。青冈亚属植物还存在许多替代现象,如青冈(Q.schottkyana)、赤皮青冈(Q.gilva)和黄毛青冈(Q.delavayi)`、云山青冈(Q.sessifolia)和窄叶青冈(Q.augustinii)为中国-日本分布式和中国-喜马拉雅分布式之间替代。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.  相似文献   

17.
18.
We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf) and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair, K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements.  相似文献   

19.
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   

20.
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   

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