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1.
昆明地区滇韭形态及染色体多态性研究   总被引:6,自引:1,他引:5  
对昆明地区滇韭的 8个当地居群开展了形态及核型研究 ,并对形态及染色体性状进行了巢式方差分析。结果表明 :滇韭的形态性状在居群内具丰富多态性 ,在居群间具明显多型性 ;核型较对称 ,存在两种倍性的分化 :梁王山居群为二倍体 (2x) ,昆明居群为四倍体(4x)。二倍体核型公式为K (2n ) =2x =16 =14m 2sm ,四倍体核型公式为K (2n ) =4x =32=2 8m 4sm。滇韭的染色体因存在倍性变化、B -染色体形态和数目变化及随体染色体的形态和大小变化而具有一定程度的多态性。  相似文献   

2.
通过测定不同的温度、水分、盐分和光照等条件下,杂三叶和地三叶(考拉)在萌发期和幼苗期的发芽率、发芽势、生长速度、叶绿素含量、组织含水量、脯氨酸含量和细胞膜透性等指标,对两者抗性进行了比较研究。结果表明,在不同盐分浓度处理下,三叶草的叶绿素含量随盐浓度的增加而降低,组织含水量变化不明显,游离脯氨酸含量随盐浓度的增加而增加,细胞膜透性随盐浓度的增加而增强;在不同水分条件处理下,三叶草的游离脯氨酸含量和细胞膜透性随水分的增加而增加,叶绿素含量和组织含水量均变化不明显;在不同光照时间处理下,三叶草的叶绿素含量和游离脯氨酸含量均变化不明显,其细胞膜透性也无较大改变,而组织含水量则随光照时间的增加而增加;在不同温度条件下处理,三叶草的叶绿素含量、组织含水量和游离脯氨酸含量均变化不明显,细胞膜透性随温度的升高而降低。另外,从各项测定结果可以看出,杂三叶的各项性状要强于地三叶。  相似文献   

3.
在检索植物C值数据库和种子数据信息库的基础上,对禾本科282种植物的基因组参数(倍性、染色体数、C值、GS值和平均每条染色体DNA含量)和种子特性(千粒重、含油量和蛋白含量)进行了统计分析。分析结果表明,禾本科植物C值在0.35~19.7 pg,大多位于1.6~3.2 pg之间,呈偏正态分布,种子千粒重在0.05~252 g,绝大多数位于0.05~20.0 g,呈偏态分布,二者平均值分别为4.14 pg和7.1 g。随着染色体倍性增加,C值在二倍体到八倍体之间显著增加,而GS值和平均每染色体DNA含量在二倍体到六倍体之间显著下降(p<0.05)。雀麦属和羊茅属随着倍性增加,C值显著增加,表现与禾本科相似的变化规律,GS值下降却不明显。相关性分析表明,禾本科植物C值与倍性、染色体数、GS值及平均每条染色体DNA含量均呈极显著正相关(p<0.01),与种子千粒重无相关性。GS值与染色体数、倍性呈极显著负相关,而与千粒重呈极显著正相关。C值与种子含油量呈显著负相关,但与种子蛋白含量之间无相关性。以上结果表明,禾本科植物在系统演化和进化过程中,主要通过倍性和染色体的增加来增大C值,可能通过某种删除或丢失机制来降低GS值,从而保持较高的适应环境能力和进化速率。  相似文献   

4.
八种国产葱属植物染色体研究   总被引:10,自引:3,他引:7  
本文对国产葱属Allium 8个种的14个居群的染色体进行了研究。其染色体基数均为x=8,其中7个居群为二倍体(2n=2x=16),6个居群为四倍体(2n=4x=32),1个居群为多倍体复合体(2n=4x=32,2n=6x=48,2n=8x=64和2n=9x=72)。并发现随体染色体十分活跃,在多倍体中其数目并不都与其倍性相对应,并有“串状随体”现象出现;在有些类群中其形态变异较大,而随体染色体杂合形式的多态现象也较普遍。本文重点讨论了随体染色体的数目、形态变异及杂合现象在葱属进化中的作用,认为随体染色体形态变异及杂合现象的出现是葱属中遗传变异的重要源泉之一。并对葱属中的染色体基数及种内多倍性问题进行了初步讨论。  相似文献   

5.
为探究白杨年龄效应导致的扦插繁殖苗退化问题,该试验以杂种三倍体‘北林雄株2号’的不同年龄苗木硬枝插穗为材料,就扦插苗生长形态、光合生理、根发育特征、插穗皮部解剖结构以及苗木生长发育过程中叶片可溶性总糖(TSS)、可溶性总蛋白(TSP)、叶绿素(Chl)、脯氨酸(Pro)、赤霉素(GA)、生长素(IAA)、脱落酸(ABA)及IAA/ABA比值等生理生化指标进行了观测。结果表明:(1)再生苗苗高、地径、叶柄长度、节间宽、叶面积、主根数、主根长、生根率、根系效果指数及净光合速率(P_n)等指标均随插穗年龄的增加而降低,而其侧根数、侧根长、胞间CO_2浓度(C_i)、气孔导度(G_s)和蒸腾速率(T_r)等指标与插穗年龄无明显相关性。(2)插穗茎皮部解剖结构显示,周皮和木质部厚度都随插穗年龄增大而增厚,韧皮部厚度则无明显变化。(3)再生苗叶片可溶性总糖、总蛋白、叶绿素、IAA、GA含量以及IAA/ABA比值等指标均随插穗年龄的增加而逐渐降低,而脯氨酸和ABA含量则随插穗年龄增加而增加。研究发现,白杨扦插苗随插穗年龄的增加累积成熟效应,使新生苗表现出整体性衰老的生长状态。  相似文献   

6.
为清楚理解和掌握染色体数目变异的内容,必须弄清有关染色体数目变异的一些重要概念,如染色体组、单倍体与一倍体、Zn、n、x符号的含意等。现将一些概念的确切含意叙述如一F。染色体倍性是指细胞中含的染色体组数,又分整倍性和非整信性,整倍性是指细胞中所含有的染色体组都是完整的染色体组,如单倍体、二倍体、三倍体等。非整倍性是指细胞中所含的染色体组处于不完整状态,一般指二倍体种成对染色体的成员增加了或减少了。在二倍体细胞或个体中,能维持配子正常功能,包括一定数目、形态结构和一定基因组成的一套染色体称为染色体组或…  相似文献   

7.
三个鲫品系DNA含量的比较研究   总被引:17,自引:3,他引:14  
采用流式细胞术 (FCM)对红鲫、彭泽鲫、异育银鲫进行红血球DNA含量的检测分析比较 ,以鉴定它们的倍性。结果显示 ,红鲫红血球的DNA含量是 3 0pg ,彭泽鲫是 4 7pg ,异育银鲫是 4 8pg。显而易见 ,彭泽鲫的DNA含量是二倍体红鲫的 1 57倍 ,异育银鲫的DNA含量是红鲫的 1 6倍。采用肾细胞直接制作染色体的方法进行红鲫、彭泽鲫、异育银鲫的染色体倍性鉴定 ,结果红鲫的染色体数目是 10 0 ,为二倍体 (2n =10 0 ) ,彭泽鲫的染色体数目是 162 ,为三倍体 (3n =162 ) ,异育银鲫的染色体数目是 156— 162 ,为三倍体 (3n =156— 162 )。研究证明 :不同品系鲫的DNA含量高低与染色体的倍性有显著的正相关性  相似文献   

8.
人类核仁形成区结构性变异与随体联合的研究   总被引:1,自引:1,他引:0  
王戈华 《遗传学报》1989,16(1):67-73
本文以硝酸银染色法研究了200对正常夫妇及200对唐氏综合征(DS)患者双亲淋巴细胞染色体核仁形成区(NOR)。结果发现双核仁形成区(dNOR)的检出率在两组人群中均为0.5%;随体联合(SA)的结果表明,负有dNOR染色体的SA频率并不随其核糖体RNA(rRNA)基因含量的明显增加而上升,提示除rRNA基因含量及其活性外,尚有其他因素影响SA的形成。dNOR携带者与DS的发生亦无明显关系。  相似文献   

9.
Cd、Fe及其复合污染对烟草叶片几项生理指标的影响   总被引:73,自引:3,他引:70  
李元  王焕校  吴玉树 《生态学报》1992,12(2):147-154
本文通过盆栽和大田模拟试验,研究了Cd,Fe,Cd+Fe,Fe+Cd处理下烟草红花大金元(Nicotiana tabacurm L.)叶片的几项生理指标的变化情况。试验表明:烟草叶片叶绿素a、叶绿素b、叶绿素a+b含量均随Cd处理浓度的增加而下降,随Fe处理浓度的增加而上升。总烟碱含量随Cd处理浓度的增加(0—100ppm)而下降,Cd 150ppm时略有上升,随Fe处理浓度的增加而上升。蛋白质含量随Cd处理浓度的增加而上升,随Fe处理浓度的增加而下降。烟草的3个生理指标表明,Cd抑制Fe对生理指标的作用,Fe抑制Cd对它们的作用,Cd与Fe相互拮抗。Cd处理的烟草叶片过氧化物酶活性和细胞膜透性的测定结果表明,过氧化物酶活性和细胞膜透性均随Cd处理浓度的增加而上升。  相似文献   

10.
为研究不同倍性木薯对干旱胁迫耐受能力的差异,本研究以木薯品种‘新选048’二倍体及其同源四倍体盆栽苗为材料,设置不同程度的干旱胁迫,研究干旱对2个倍性木薯苗形态、渗透调节物质、抗氧化能力及内源激素的影响。结果表明:随着干旱胁迫程度的加强,2个倍性的木薯叶片均出现下垂、萎蔫、变黄,进而干枯的症状,二倍体表现更为严重。可溶性蛋白和脯氨酸(Pro)含量基本随着胁迫程度的加剧而逐渐增加,二倍体更为敏感,积累量大于四倍体。2个倍性材料的抗氧化相关指标基本随着干旱程度的加强而升高,四倍体总抗氧化能力(T-AOC)和超氧化物歧化酶(SOD)活性比二倍体高,而过氧化氢(H_2O_2)含量、丙二醛(MDA)含量、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性比二倍体低。随着干旱程度的增加,2个倍性材料的赤霉素(GA)含量先上升后下降,在四倍体中的含量始终大于二倍体;吲哚乙酸(IAA)含量变化不规则;玉米素核苷(ZR)含量在二倍体中逐渐下降,而在四倍体中先轻微上升后下降,在四倍体中下降幅度较大,但ZR含量在四倍体中始终大于二倍体中的含量;脱落酸(ABA)含量先上升后下降,轻度胁迫下四倍体大于二倍体,其他程度胁迫下二倍体大于四倍体。综合分析,在干旱胁迫下,四倍体木薯产生较强的抗氧化能力,同时通过GA、ZR和ABA的协同作用,延长叶片的功能期,从而达到比二倍体抗旱的效果。  相似文献   

11.
12.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

13.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

14.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

15.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

16.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

17.
18.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

19.
Cytoskeleton and mitochondrial morphology and function   总被引:10,自引:0,他引:10  
It has been well established that the cytoskeleton is an essential modulator of cell morphology and motility, intracytoplasmic transport and mitosis, however cytoskeletal linkage to the organelles has not been unequivocally demonstrated. Indeed, cytoskeleton appears to be essential in determining and modulating gene phenotype as a function of cellular environment. According to recent studies, the organization of the cytoskeleton network together with associated protein(s) could be essential in regulating mitochondrial function and particularly the permeability of the mitochondrial outer membrane to ADP. The aim of this chapter is to summarize the main properties of the cytoskeletal environment of mitochondria and the possible role(s) of this network in mitochondrial function in myocytes.  相似文献   

20.
Many patients have sensitivities to multiple species of storage and house dust mites. It is not clear if this is because patients have multiple sensitivities to species-specific mite allergens or if these mites share many cross-reacting allergens. Our objective was to further define the cross-allergenicity between several species of storage and house dust mites using crossed-immunoelectrophoresis (CIE), crossed-radioimmunoelectrophoresis (CRIE), immunoblotting, and ELISA. CIE and CRIE reactions revealed that storage mites shared two cross-antigenic molecules and one of these bound IgE in a serum pool from mite allergic patients. Antibody in anti-sera built to each species of mite recognized many SDS–PAGE resolved proteins of other mite species and this suggested the potential for other cross-reactive allergens. Among patient sera, IgE bound to many different proteins but few had IgE that bound to a protein with common molecular weights across the mite species and this suggested mostly species-specific allergens. Antiserum built to each mite species precipitated one protein in shrimp extracts that bound anti-Der p 10 (tropomyosin) and IgE in the serum pool. Anti-Der p 10 showed strong binding to shrimp tropomyosin but very little to any of the mite proteins. ELISA showed the mite extracts contained very little tropomyosin. The storage and dust mites investigated contain mostly species-specific allergens and very small amounts of the pan-allergen tropomyosin compared to shrimp and snail.  相似文献   

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