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1.
姜传明  徐娜  李斌 《植物研究》2000,20(2):162-167
基于野外调查及形态学、解剖学、细胞学和植物化学的研究,在黑龙江省发现了一种新的柴胡属植物,该植物与红柴胡混生于草甸草原、灌丛和柞树林等群落之中,其不同于红柴胡的特点是,根黑色,根头稀具纤维,叶略宽;根中具木纤维群,叶下表皮下方无栅栏组织;染色体数目2n=26或20,具二型性;柴胡皂甙较多而挥发油较少。该植物与传统中药北柴胡相似,且分布广,数量大,是黑龙江省的一种新的柴胡资源。  相似文献   

2.
基于野外调查及形态学、解剖学、细胞学和植物化学的研究,在黑龙江省发现了一种新的柴胡属植物,该植物与红柴胡混生于划甸草原、灌丛和柞树林等群落之中,其不同于红柴胡的特点是,根黑色,根头稀具纤维,叶略宽;根中具木纤维群,叶下表皮下方无栅栏组织;染色体数目2n=26或20,具二型性;柴胡皂甙较多而挥发油较少。该植物与传统中药北柴胡相似,且分布广,数量大,是黑龙江省的一种新的柴胡资源。  相似文献   

3.
花粉与孢子为形态学上的重要实体,它反映出植物进化的某些侧面与事实。在孢子外壁的各种特征中,萌发孔被认为是最保守的。菌藻类植物的孢子为原始型(其萌发孔不明显)颈卵器植物的孢粉为三型的(具三裂缝,单裂缝和无裂缝);而被子植物的花粉为多型的(具沟、沟孔、孔等等,且在数目与形状上有很多的变化)。三型孢粉为被子植物前身的颈卵器植物的特征,它在被子植物中的出现可能被看成是提供了一种表明该类中原始分类群的指示。面对这—背景,我们主张被子植物在其进化系列中是三种系发生的,有三条独立的系统发育主干,即单子叶植物主干、木兰类双子叶植物主干和毛茛类双子叶植物主干。  相似文献   

4.
贺兰山不同生境旱生灌木的解剖学研究   总被引:9,自引:1,他引:8  
贺兰山荒漠地带三种不同基质生境的20种旱生灌木的营养器官的比较解剖学研究表明:其共同特点是叶片的表面积/体积的比值小,叶表具厚的角质层、表皮毛,气孔下陷、并具孔下室,叶向中栅栏组织发达;轴器官中木栓层细胞层数多,皮层较厚,机械组织发达,木薄壁组织及髓部细胞的细胞壁术化加厚,根内都具周皮、木质部的导管分子大小不一、频率较高。此外,根、茎、叶中普遍存在粘液细胞和草酸钙结晶,部分植物的根和茎内有异常维管组织。这些结构特征都与早生环境相关,而不同基质生境中生长的植物尚存在一定差异。  相似文献   

5.
利用常规石蜡制片技术对生长在联峰山上的10种植物营养器官进行解剖学观察。主要结果如下:(1)叶表皮细胞均为1层,绝大多数无表皮毛,气孔少;异面叶或等面叶;中脉维管束束数1至多个。(2)根:主要为次生构造,也有初生构造的。但大多数植物无周皮;皮层细胞的层数在不同植物中差异较大;有些植物次生韧皮部普遍不发达,次生木质部较韧皮部明显。(3)茎:表皮细胞均为1层,具角质膜;皮层细胞层数普遍较少,外皮层有机械组织存在;维管束数目多个并呈一圈排列,外韧或双韧;髓部发达,髓射线明显。该研究结果表明10种植物具有中生植物或阴性植物的结构特点,是植物长期适应环境条件的结果;该研究为更好地开发和利用植物提供了解剖学依据。  相似文献   

6.
本文用方差分析区别具台木类木材的三个种:太原台木(Dadoxylon taiyuanensis),生根无髓根(Amyelon radicans)和徐氏无髓根(A.xui),并同国外的种比较,结果表明,用这种方法能定量地研究植物性状之间的区别,并得到较好的效果。  相似文献   

7.
刺镰蕨在早泥盆世是一种广布于世界的植物,尽管报道自许多地点,但远未完全地了解它,其主要原因是能育材料罕见。我们观察的标本采自贵州早泥盆世的丹林组。它显示具柄的孢子囊侧生于靠近叶腋的轴上,我们的标本近似球形的孢子囊和它的形态略小于雷诺的肾形孢子囊外,其它方面如:带状的营养轴上具有疏螺旋排列的镰刀状叶,具短柄的孢子囊侧生于轴上以及管胞具穿孔壁等性状与雷诺修订后的刺镰蕨完全一致。我们同意雷诺的观点,将镰蕨目升为纲,与工蕨纲和石松纲并列。它的系统位置是介于工蕨纲和石松纲之间。其下包含一目、一科三个属——镰蕨属、巴拉格瓦纳彻属和星木属。这种植物的生殖部分在中国尚属首次报道。  相似文献   

8.
红树林保护区是一个由生物和环境组成的有机组合的开放系统, 是世界上最富多样性,生产力最高的海洋生态系统之一。红树林特殊的植物生态特性胎生 红树植物不少具有胎生现象, 这种特征有利于在海滩上繁殖和远距离传播。一般情况是红树植物的果实成熟时仍留在树上, 种子在母树上的果实内发芽, 形成幼苗, 掉进泥中后, 即可扎根成苗; 若掉入涨潮水中, 可远漂传播, 遇到潮落时再在滩泥中扎根生长。根系 红树植物具特殊的根系, 可分为支柱根、板状根和呼吸根。即适应泥泞的红树植物, 从茎基伸出拱形下弯的支柱根或宽厚的板根, 以抗御风浪和起到…  相似文献   

9.
本文用方差分析区别具台木类木材的三个种:太原台木(Dadoxylon taiyuanensis),生根无髓根(Amyelon radicans)和徐氏无髓根(A.xui),并同国外的种比较,结果表明,用这种方法能定量地研究植物性状之间的区别,并得到较好的效果。  相似文献   

10.
在现存的具维管束植物中,究竟是哪一种植物代表了这一类群植物的基础谱系?是哪一种植物在古生代早期栖居在陆地生境?这是植物学家们长期争论而未获解决的问题。一种说法认为,裸蕨类植物笤帚蕨(whisk fern)没有根,在很多方面都酷似某些早期的化石植物。也有人认为,石松拥有经历4亿年历史的化石植物,揭示石松在植物进化史上具有原始的地位。最近,美国植物学家 Raubeson 和 Jansen 检测了具维管束植物全部主要的现存谱系的代表植物叶绿体基因组的结构单位,并作了比较,所获得的证据支持这一观点,即:石松是具维管束的陆地植物第一次发生进化分歧时留传绵衍的唯一的现代后裔。  相似文献   

11.
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   

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   

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14.
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   

15.
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   

16.
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   

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.
《Ibis》1894,36(3):447-460
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Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

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