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91.
槟榔(Areca catechu L.)的民族植物学 总被引:3,自引:0,他引:3
本文从民族植物学的观点介绍了我国南方各省嚼槟榔的习俗、历史及演变,分析了这个习俗的形成原因及槟榔的药用价值。作者认为咀嚼槟榔有成瘾性,但是否对人的中枢神经系统有损害,必须进一步研究。作者对这种习俗提出了几点看法和建议,对槟榔的开发利用有重要参考价值。 相似文献
92.
Discrimination Amongst Leishmania by Polymerase Chain Reaction and Hybridization with Small Subunit Ribosomal DNA Derived Oligonucleotides 总被引:1,自引:0,他引:1
SILVIA R. B. ULIANA KIMBERLYN NELSON STEPHEN M. BEVERLEY ERNEY P. CAMARGO LUCILE M. FLOETER-WINTER 《The Journal of eukaryotic microbiology》1994,41(4):324-330
ABSTRACT. A method for discriminating among Leishmania is described, based upon small subunit ribosomal DNA sequence differences. The method was to amplify the entire 2.2 kb small subunit rDNA by polymerase chain reaction using conserved primers specific for the 5' and 3' termini of the small subunit ribosomal RNA, and then hybridize the product dotted onto nylon membranes with labeled oligonucleotides. The design of the hybridization probes was based upon complete small subunit rDNA sequences from L. amazonensis, L. major and L. guyanensis and partial sequences of L. mexicana, L. braziliensis, L. tropica and L. chagasi. A high degree of sequence similarity (> 99%) among species was found. However, sufficient sequence divergence occurred to permit the design of internal oligonucleotide probes specific for species complexes. This procedure successfully discriminated amongst a wide range of Leishmania isolates. The method detected as few as 10 cultured organisms and detected parasites in tissue samples from experimentally infected animals. Non-radioactive labeling showed the same specificity and sensitivity as radioactive probes. 相似文献
93.
Sarvesh Adda T. P. Reddy P. B. Kavi Kishor 《In vitro cellular & developmental biology. Plant》1994,30(2):104-107
Summary Induction of somatic embryogenesis, shoot organogenesis, and subsequent plant regeneration in niger seem to be dependent on
genotype, choice of explant, and composition of media growth regulators. Two distinct regeneration protocols have been developed
for somatic embryogenesis and shoot organogenesis. Somatic embryogenesis was induced from epicotyls and cotyledonary explants
(9 to 35%) (but not from hypocotyls and roots) in presence of 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic
acid, and 2,4,5-trichlorophenoxypropionic acid. These embryos matured in MS medium containing Kinetin plus naphthalene acetic
acid (NAA), Kinetin plus Zeatin, and Kinetin plus abscisic acid (ABA). Matured embryos could be germinated on LS and MS basal
media without hormones. Non-embryogenic callus initiated on Linsmaier and Skoog’s (LS) medium from cotyledons of six
different genotypes produced shoots (9 to 32%) on Murashige and Skoog’s (MS) medium fortified with 6-benzylaminopurine
(BAP, 0.5 mg · liter−1), and BAP (1 mg · liter−1) plus NAA (0.1 mg · liter−1). These shoots were rooted with 100% frequency by using indole-3-acetic acid or NAA and transferred successfully to the soil. 相似文献
94.
S. CARRÉ J. N. TASEI J. Le GUEN J. MESQUIDA G. MORIN 《The Annals of applied biology》1993,122(3):555-568
A simplified and non-destructive method using starch gel electrophoresis has been developed on seeds to identify inbred lines of Vicia faba and assess outcrossing rates and gene dispersal in pollination experiments. Six enzyme systems (Alcohol dehydrogenase, Aspartate aminotransferase, Glucose-6-phosphate isomerase, Isocitrate dehydrogenase, Phosphogluconate dehydrogenase and Shikimate dehydrogenase) were analysed from parental lines, crosses performed between lines bearing dissimilar isozyme patterns in pollination cages with Bombus and F2 progenies obtained from manual selfing of F1 hybrids. The allozymes at each of the seven studied loci segregated in the expected Mendelian fashion and behaved in a co-dominant manner except for the Adh-2 locus where the only variant was a null allele. No evidence of genetic linkage was observed between at least 13 of the 15 pairs of the studied loci. Percentage of cross fertilisation by Bombus between seven pairs of inbred lines ranged between 1.7% and 28.3%. Pollen transfer between a donor line and a recipient line by two species of Bombus did not lead to differences in outcrossing rates (both about 8%). The new PGD marker with two loci at three alleles each is particularly discriminating and valuable in pollination studies and breeding of V. faba. 相似文献
95.
Quantitative trait loci influencing protein and starch concentration in the Illinois Long Term Selection maize strains 总被引:15,自引:0,他引:15
I. L. Goldman T. R. Rocheford J. W. Dudley 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,87(1-2):217-224
A study was initiated to determine the number, chromosomal location, and magnitude of effect of QTL (quantitative trait loci or locus depending on context) controlling protein and starch concentration in the maize (Zea mays L.) kernel. Restriction fragment length polymorphism (RFLP) analysis was performed on 100 F3 families derived from a cross of two strains, Illinois High Protein (IHP), X Illinois Low Protein (ILP), which had been divergently selected for protein concentration for 76 generations as part of the Illinois Long Term Selection Experiment. These families were analyzed for kernel protein and starch in replicated field trials during 1990 and 1991. A series of 90 genomic and cDNA clones distributed throughout the maize genome were chosen for their ability to detect RFLP between IHP and ILP. These clones were hybridized with DNA extracted from the 100 F3 families, revealing 100 polymorphic loci. Single factor analysis of variance revealed significant QTL associations of many loci with both protein and starch concentration (P < 0.05 level). Twenty-two loci distributed on 10 chromosome arms were significantly associated with protein concentration, 19 loci on 9 chromosome arms were significantly associated with starch concentration. Sixteen of these loci were significant for both protein and starch concentration. Clusters of 3 or more significant loci were detected on chromosome arms 3L, 5S, and 7L for protein concentration, suggesting the presence of QTL with large effects at these locations. A QTL with large additive effects on protein and starch concentration was detected on chromosome arm 3L. RFLP alleles at this QTL were found to be linked with RFLP alleles at the Shrunken-2 (Sh2) locus, a structural gene encoding the major subunit of the starch synthetic enzyme ADP-glucose pyrophosphorylase. A multiple linear regression model consisting of 6 significant RFLP loci on different chromosomes explained over 64 % of the total variation for kernel protein concentration. Similar results were detected for starch concentration. Thus, several chromosomal regions with large effects may be responsible for a significant portion of the changes in kernel protein and starch concentration in the Illinois Long Term Selection Experiment. 相似文献
96.
B. Arnholdt-Schmitt 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,85(6-7):793-800
Summary Rapid genomic DNA variation due to methylation and copy number alteration was observed in carrot root explants 6 h after inoculation and during a 36-h period of exponential callus growth. De novo methylation and amplification of restricted BspNI fragments of low molecular weight occurred before cell cycle activation and should, therefore, be independent of progression through the S-phase of the cell cycle. Growth regulators seemed to influence the amplification pattern indirectly by regulating cell division activity. In exponentially growing callus tissue the copy number of most of the repetitive fragments was dramatically reduced. It is presumed that this reduction in the copy number of repetitive fragments is characteristic of rejuvenilization. 3-Indole-acetic-acid (IAA) and inositol in the medium increased the degree of unspecific genomic DNA methylation in growing rhizogenic carrot callus tissue in the absence of kinetin, which inhibits root induction at that stage. A possible relation to the induction of rhizogenesis is considered. The observed reduction in number of repetitive restriction fragments and the increase in DNA methylation are gross changes covering the total genome. The results are discussed in relation to the controversy concerning the general biological significance of the methylation and amplification of DNA sequences. 相似文献
97.
Margot Schulz T. Klockenbring Carola Hunte Heide Schnabl 《Plant biology (Stuttgart, Germany)》1993,106(2):143-145
Western immunoblot analysis of protein extracts prepared from epidermal peels, whole leaves, and mesophyll protoplasts with ubiquitin and PEPCase antibodies indicated ubiquitinated PEPCase bands and degradation products only in crude extracts which have been obtained in the presence of the proteolysis inhibitors leupeptin and hemin. After ammonium sulfate precipitation and further purification, PEPCase forms were stable and not ubiquitinated. It is assumed, that only a certain part of PEPCase is degraded via the ubiquitin-dependent proteolysis. 相似文献
98.
A system for somatic embryogenesis and plant regeneration of spinach from hypocotyl segments has been established. Callus
was induced on solid media supplemented with 8.5–15.0 mg.l−1 of indole-3-acetic acid and 3.46–34.64 mg.l−1 gibberellic acid. Callus was then subcultured on different media (solid or liquid) with or without IAA, or continuously maintained
on the initiating media. Somatic embryos were obtained in subcultures on IAA-containing media as well as in long-term cultures
on initiating media. The best results were achieved in liquid subcultures. About 60% of plantlets survived after transplanting
in pots. 相似文献
99.
Using a physicochemical method, the distribution of endogenous indole-3-acetic acid (IAA) was measured in the peripheral and central cell layers, as well as in the illuminated and shaded sides of phototropically stimulated radish hypocotyls (Raphanus sativus var. hortensis f. gigantissimus Makino). The IAA was evenly distributed over the illuminated and shaded sides in the first and second positive phototropic curvatures induced by a pulse or a continuous unilateral illumination with blue light. Also, no net exchange of the IAA between the peripheral and central cell layers was observed during these curvatures. These results suggest that phototropism of radish hypocotyls cannot be described by the Cholodny-Went theory. 相似文献
100.