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121.
The glandular secretory system in Cannabis sativa L. (marihuana) consists of three types of capitate glandular hairs (termed bulbous, capitate-sessile, and capitate-stalked) distinguishable by their morphology, development, and physiology. These gland types occur together in greatest abundance and developmental complexity on the abaxial surface of bracts which ensheath the developing ovary. Bulbous and capitate-sessile glands are initiated on very young bract primordia and attain maturity during early stages of bract growth. Capitate-stalked glands are initiated later in bract growth and undergo development and maturation on medium, to full sized bracts. Glands are epidermal in origin and derived, with one exception, from a single epidermal initial. The capitate-stalked gland is the exception and is of special interest because it possesses a multicellular stalk secondarily derived from surrounding epidermal and subepidermal cells. Glands differentiate early in development into an upper secretory portion and a subtending auxiliary portion. The secretory portion, depending on gland type, may range from a few cells to a large, flattened multicellular disc of secretory cells. The secretory portion produces a membrane-bound resinous product which caps the secretory cells. Capitate-stalked glands are considered to be of particular evolutionary significance because they may represent a gland type secondarily derived from existing capitate-sessile glands. 相似文献
122.
A rapid method is described for the identification of lectin binding membrane glycocomponents in polyacrylamide gels. The method requires only small quantities of membrane material and is applicable to a wide variety of lectins. Solubilized membrane components are electrophoretically separated according to molecular weight in a SDS-polyacrylamide gel. The gel is then incubated in a solution containing the 125I-lectin. After elution of unbound 125I-lectin, the gel is dried down and those bands which have bound the 125I-lectin are identified by radioautography. The amount of bound 125I-lectin can be quantified by either densitometric scanning of the radioautogram or by liquid scintillation counting of the dried gel. 相似文献
123.
N.S. Ranganathan Paul A. Srere Tracy C. Linn 《Archives of biochemistry and biophysics》1980,204(1):52-58
The dephospho- form of rat liver citrate lyase has been prepared by treating purified [32P]-ATP citrate lyase with a partially purified phosphatase. A comparison of the properties of the phospho- and dephosphoenzyme has been performed. The pH optima were the same for both forms of the enzyme in four different buffer systems although the optimum values varied identically for both enzyme forms with the buffer. Both the phospho- and dephosphoenzymes show the same kinetic properties except for the Km observed for ATP in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid buffer system where it was 54 μm for the phosphoenzyme and 292 μm for the dephosphoenzyme. The present study also indicates that both enzymes are cleaved by trypsin and lysosomal proteases in a similar manner. Both forms of the enzyme tend to associate with mitochondria to the same extent and both enzymes have identical temperature stability curves. 相似文献
124.
Quantitative and qualitative studies were made of the fungi of the air in Barcelona City. The genera Cladosporium and Alternaria formed two of the most important components of the fungus population studied during a two-year period running from January 1976 through January 1978. Penicillium species formed the 16.3 % of the total colonies while Aspergillus species represented only the 2.8 %. The occurrence of these genera was greatly affected by climatic conditions. An attempt was made to summariza the data of various kinds of fungi on a volumetric basis. Most of the fungi reported here have been identified as far as genera.
Résumé Une étude qualitative ainsi que quantitative a été réalisée sur la population fongique présente dans l'atmosphère de la ville de Barcelone. Les genres Cladosporium et Alternaria constituent les moisissures les plus inportantes quant à leur présence parmis la population fongique étudiée durant la période de deux ans comprise entre le mois de Janvier 1976 et le mois de Janvier 1978. Le genre Pénicillium représentait le 16.3% de la totalité des colonies isolées, tandis que le genre Aspergillus ne représentait que le 2.8%. La présence d'espéces de ces genres était largement influencée par les conditions climatologiques. Les données sur la présence des différents genres de moisissures ont été établies sur une base volumétrique. La plupart des moisissures identifiables l'ont été jusqu'au genre.相似文献
125.
The relationship between protein synthesis and the incorporation of [3H]gibberellin A1 ([3H]GA1) into a 2,000xg pelletable (2KP) fraction from lettuce (Lactuca sativa L.) hypocotyl sections has been investigated. Concentrations of D-2-(4-methyl-2,6-dinitroanilino)-N-methylpropionamide (MDMP) between 10-7 M and 10-4 M caused increasing inhibition of growth, 2KP labelling and incorporation of [14C]leucine into soluble protein. Growth and 2KP radioactivity were highly correlated (r=0.996). Transfer to MDMP early or late in the course of GA response caused reductions in both growth and incorporation into the 2KP fraction. Exposure to the inhibitor had more effect at 4 h than at 20 h. The proportions of alkali-soluble and insoluble radioactivity in the 2KP fraction were also altered by this treatment. The implications of these findings are discussed.Abbreviations GA1
gibberellin A1
- MDMP
D-2-(4-methyl-2,6-dinitroanilino)-N-methylpropionamide
- 2KP
a2,000xg pelletable fraction 相似文献
126.
Summary The sexual development of 14 girls with non-mosaic monocentric 46,X,iXq karyotype was studied. Seven out of eight girls were found to have immature secondary sexual characteristics and amenorrhoea, a finding greatly contrasting with that in Triplo-X girls. The relative ineffectiveness of the isochromosome Xq in maintaining fertility may be due to the absence of one short arm, which probably also carries a gonadal determinant. Alternatively, the presence of two inactivation sites on one isochromosome may render the gonadal determinants inactive at an important stage in gonadal development. 相似文献
127.
Summary The degenerative reaction of mitochondria to tricresylphosphate (TCP) poisoning in spinal ganglion cells of Slow Loris (Nycticebus coucang coucang) were studied with the electron microscope. In neurones of animals treated with TCP, mitochondria display various stages of alterations which confirm mitochondrial involvement in TCP poisoning. The role of degenerated mitochondria in the formation of neuronal lipofuscin is discussed. It is suggested that the lipofuscin granule is a metabolic product inherently related to mitochondrial degeneration, irrespective of the primary cause: ageing or intoxication.Fellow of the Deutscher Akademischer Austauschdienst on study leave from the Medical Faculty, University of SingaporeA grant from the Deutsche Forschungsgemeinschaft (Gl. 28/20) is gratefully acknowledgedThe skilfull technical assistance of Mr. Tajuddin b.M. Ali, Mr. P. Gopal, Mr. R. Dungan and Mrs. C. Weinrichter is gratefully acknowledged 相似文献
128.
Paul M. Dewick 《Phytochemistry》1977,16(1):93-97
Feeding experiments have demonstrated that 7,2′-dihydroxy-4′-methoxy-isoflavone-[14C-Me] and -isoflavanone-[14C-Me] are extremely efficient precursors of the phytoalexin demethylhomopterocarpin in Cu2+-treated red clover seedlings. Neither of these compounds, nor demethylhomopterocarpin-[14C-Me], was incorporated into a second pterocarpan phytoalexin, maackiain. 3-Hydroxy-9-methoxypterocarp-6a-ene-[14C-Me] was a poor precursor of both pterocarpans. A biosynthetic pathway to demethylhomopterocarpin via 2′-hydroxylation of formononetin (7-hydroxy-4′-methoxyisoflavone) and subsequent reduction to the isoflavanone is proposed. The conversion of this isoflavanone into the pterocarpan may involve the corresponding isoflavanol and a carbonium ion intermediate. The branch-point to maackiain is probably at the formononetin stage. The presence of two coumestans, 9-O-methylcoumestrol and medicagol, previously unreported in red clover, is demonstrated. Biosynthetic implications are discussed. 相似文献
129.
130.
The occurrence of larval Anisakis in North Sea herring was examined during the period 1965-1972 using a sampling method which yielded comparable data for all eight years. Data on abundance of infestation in several herring stocks pointed to remarkable fluctuations over the study period with an increase in the period 1966-1968 followed by a decrease in the period 1968-1972. Of various hypotheses that may explain this situation, it is concluded that changes in the migration behaviour of the herring may be responsible. Other data and statistics are discussed with special reference to variations in infestation level in different samples and to the occurrence of adult nematodes in marine mammals. 相似文献