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The glandular trichomes ofFagoniaconsist of one secretory celland a multicellular stalk, which develops by division, elongationand elevation of epidermal cells. The latter become seperatedfrom the mesophyll and a subepidermal chamber is formed. Thelength of the stalk, which differs in the various species orvarieties is determined by the number of cell divisions and/or the extent of cell elongation. Although the basic morphologyand development of the trichomes of the species and varietiesexamined are similar, two types of mature trichomes can be distinguished:one occurs in the two examined varieties ofF. mollisand thesecond inF. glutinosaandF. arabica. The secretory cells of thesecond type possess a very thick wall and bear a porous cupuleon their top. Histochemical tests revealed that the sticky substancesecreted by the secretory cells contains mainly polysaccharidesand lipophilic compounds. The secreted material exhibits autofluorescence.InF. mollisvar.hispidachanges in the amount and shape of thefluorescent material inside the secretory cell, during the courseof development, have been observed. The contribution of theglandular trichomes inFagoniaspecies to survival in hot desertconditions is discussed. Fagonia; glandular trichomes; subepidermal chamber; secreted material; adaptation to desert conditions; stalk; fluorescence 相似文献
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Movement of 14C-assimilates from young and mature leaves to young rose shoots (Rosa hybrida cv. Marimba) was examined in two developmental stages. In the first stage after bud breaking the young shoot, especially its tip, depends for its supply of assimilates mainly on the mature foliage. At this stage young leaves are powerful sinks and retain 97% of their own photosynthates. The translocated 3% move mainly to the roots. At a later stage, just after the appearance of the flower bud, most of the leaves on the shoot become a source. The upper leaves supply assimilates to the flower bud and to the upper part of the stem. The 14C-assimilates from the lower leaves move in two directions, the larger part being directed downward. 相似文献
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TOSHIRO KAGESHITA ZHI JIAN CHEN JIN-WOO KIM MIKIHIRO KUSAMA ULANA MARIA KEKISH TRACY TRUJILLO MASSIMO TEMPONI ABRAHAM MITTELMAN SOLDANO FERRONE 《Pigment cell & melanoma research》1988,1(Z1):185-191
Following a discussion of the rationale underlying the selection of human melanoma to test the usefulness of anti-idiotypic monoclonal antibodies in the therapy of solid tumors, the development of the anti-idiotypic monoclonal antibody MoAb) MF11–30 is described. This antibody recognizes a private idiotope within the antigen-combining site of the immunizing antihuman high molecular weight melanoma-associated antigen MoAb 225.28. The results of a phase I clinical trial with the MoAb MF11–30 in patients with advanced melanoma are described. The lack of toxic effects and the minor responses in six patients suggest that these studies should be extended to a larger number of patients with an emphasis on the analysis of the mechanisms underlying the clinical response. 相似文献
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Single node explants of ‘Baccara’ rose were fed through the basal cut surface with 14C-sucrose in agar. Accumulation of 14C-metabolites by buds is a steady process, while a quick uptake occurs in the stem piece during the initial stage of incubation suggesting a passive uptake at this stage. The uppermost 5-leaflet node buds had an initially higher 14C-uptake than the lowest bud. This difference disappeared after 2–3 days when growth started in both buds. Light enhanced uptake of 14C-sucrose by both stem pieces and buds. Accumulation of 14C-metabolites by buds was in direct relationship to buds deviation from the direction of gravity. This phenomenon was not evident in the stem part of the explant. 相似文献