13,015 research outputs found

    Anatomical and histochemical analysis of vegetative organs of Vernonia ferruginea Less. (Asteraceae)

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    Vernonia ferruginea Less. is a perennial shrub species, present in several regions of Brazil, especially in the savanna. It is popularly used as a phytotherapic. This fact justifies the need to anatomically characterize the plant for its accurate identification and to conduct histochemical studies with the aim of identifying the chemical nature of its cellular constituents. The species-specific data will contribute significantly to pharmaceutical quality control and also provide information about the sites of specific chemical compounds. Samples of V. ferruginea vegetative organs were collected and submitted to the usual plant anatomy and histochemical techniques. The leaves are anfihipoestomática with anomocytic stomata; have tector and glandular trichomes that store essential oils. The stem has collateral-type vascular bundles arranged in a eustele structure; it also has glandular and tector trichomes. The root has brachysclereids, endoderm with various chemical compounds and vascular bundles having axial elements and rays. Few differences were found in the structure of vegetative organs in relation to other species of the genus, confirming the importance of the details shown.Key words: Plant anatomy, assapeixe-branco, essential oils

    Evolution and relationships of the conifer seed cone telemachus: Evidence from the triassic of antarctica

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    The seed cone Telemachus is known from several Triassic localities in Gondwana. New specimens from two localities in Antarctica provide additional information about the type species, Telemachus elongatus, based on details of morphology and anatomy revealed by using a modified transfer technique on the compressed plants. Seed cones of T. elongatus are up to 6.0 cm long and characterized by conspicuous, elongate bracts. A second Antarctic species, described here as Telemachus antarcticus, is segregated, based on a shorter bract and differences in cone size. Newly recognized features of the genus include the shape, size, and disposition of the ovules; vascularization of the ovuliferous complex; and scale and bract histology. As a result of this new information, it is now possible to compare Telemachus with the permineralized Middle Triassic conifer seed cone Parasciadopitys from the Central Transantarctic Mountains. The similarities between the two genera make it possible to relate organs in different preservational modes and to develop a more complete concept for this widely distributed Gondwana conifer. Placing the Telemachus plant within a phylogenetic context makes it possible to evaluate the relationship with other so-called transitional conifers, an informal group that has been interpreted as intermediate between Paleozoic and modern conifers.Fil: Escapa, Ignacio Hernán. University of Kansas; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Decombeix, Anne-Laure. University of Kansas; Estados UnidosFil: Taylor, Edith L.. University of Kansas; Estados UnidosFil: Taylor, Thomas N.. University of Kansas; Estados Unido

    Dormancy in reproductive vegetative buds in creeping perennials dominating the agricultural weed flora in Scandinavia

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    Dormancy, which is the inability to initiate normal growth under otherwise favourable conditions, is an adaptation to escape sprouting prior to seasonal cold temperatures and/or drought in areas where winters are harsh or summers dry. Dormancy in woody perennials of northern temperate areas is, in general, induced by photoperiodic and/or temperature changes, and released after prolonged exposure to chilling. Besides being species specific, northern ecotypes are usually more sensitive to inductive signals than are southern ecotypes (in cold temperate areas). Dormancy in perennial weeds has been little studied, but might influence the effect of weed control measures. These often involve repeated fragmentation of the roots or rhizomes to stimulate re-sprouting, thus reducing the storage of nutrient reserves. Such measures would be a waste of energy and time if conducted during a period of dormancy. Furthermore, herbicide applications might be less efficient, since there is no or little transport to reproductive organs. In this thesis, the autumnal growth pattern of five perennial weeds, which all propagate vegetatively from underground adventitious or axillary buds, has been studied. In an outdoor pot experiment, emergence from defoliated plants with undisturbed underground systems was followed at two weeks intervals from late July to late January/April, for 2 years. During the second year, sprouting capacity from root and rhizome fragments was also tested. Emergence was impaired in Cirsium arvense, Equisetum arvense, Sonchus arvensis and Tussilago farfara during a period in September-October. This seasonality was, however, not preserved in C. arvense root buds after fragmentation of the root system. Fragmented rhizomes of Elytrigia repens, originating from southern Sweden, sprouted less readily in September-October. The shoot-to-rhizome ratio of this species was lowest during the same period. A climate chamber experiment suggested a photoperiodic control of sprouting from fragments of S. arvensis, with least sprouting in short photoperiods (12 h of light) combined with high temperature. None of the 12 combinations of photoperiods and temperatures used induced dormancy in C. arvense. In neither of the experiments could timing of dormancy onset be attributed to the latitudinal origin of the plants

    Cystomanometry – One of the Assessment Methods of the Urodynamic Indexes in Patients with Infiltrative Cervical Cancer

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    Aim: To evaluate contractile function of urinary bladder in patients with infiltrative cervical cancer after nerve-sparing radical hysterectomy (NSRH).Patients and Methods: Ninety patients with infiltrative cervical cancer were treated with nerve-sparing radical hysterectomy (n=45, NSRH group), or radical hysterectomy (RHE III) without preservation of pelvic autonomic plexuses (n=45, RHE group). Cystomanometry was carried out using urodynamic apparatus “Uro-Pro” by standard method.Results: Using cystomanometry, we have evaluated the main urodynamic indexes such as pressure upon bladder filling (P1), first vesical tenesmus pressure (P2); change of detrusor pressure upon change of bladder volume (P), volume of urinary bladder (V), and complience of urinary bladder wall (C) at preoperative period and postoperative period in both groups of patients. While at preoperative period P1 indexes did not differ significantly between the groups, after NSRH performance, P1 values were significantly higher than P1 values in the group of patients treated with RHE III (8,29±1,1 cm H2O versus 3,51±0,8 cm H2O (р<0,05)). P2 indexes in patients from both groups before and after surgical treatment differed significantly and were 6,82±0,4 cm H2O and 12,27±1,2 cm H2O (р<0,05) in NSRH group, and 5,44±0,6 cm H2O and 10,62±1,1 cm H2O (р<0,05) in RHE III group. The P value in both patients groups before and after the surgical treatments was significantly different, and demonstrated a gradual elevation of urinary bladder pressure, especially in the patients from RHE III treated group. Urinary bladder volume at preoperative and postoperative periods in NSRH-treated group remained practically unaltered (209,78±14,2 ml and 216,86±14,9 ml (р>0,5) respectively), while in the patients from RHE III-treated group after surgical treatment an urinary bladder volume significantly decreased from 188,4±10,5 ml to 161,9±9,8 ml (р<0,05). An analysis of compliance of urinary bladder wall (C) has shown that after surgical treatment in RHE group C value decreased by 75% while in NSE group this index decreased just by 25%.Conclusions: The data of urodynamic study evidence the better preservation of urinary bladder functions in patients with infiltrative cervical cancer after NSRH than in the patients treated with RHE III

    Gymnostoma tasmanianum sp nov., a fossil Casuarinaceae from the Early Oligocene of Little Rapid River, Tasmania, Australia

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    Int. J Plant Sci. 164(4):629–634. 2003. © 2003 by The University of ChicagoMacrofossils of Casuarinaceae from Early Oligocene sediments at Little Rapid River, Tasmania, are assigned to a new species, Gymnostoma tasmanianum. This is only the second species of fossil Gymnostoma to be formally described and the first species of Gymnostoma to be described from Tasmania. The species is known from both vegetative and reproductive organs. The new taxon is distinguished from other known species by its small stomata, short article length and tooth width, small length:width ratio of articles, glabrous articles, stomata in two to five rows, and teeth elongate with acute apices and sinuses. The fossil record shows that Gymnostoma once had a much wider distribution in Australia than its current occurrence in far north Queensland.Greg Guerin and Robert S. Hil

    Berberis microphylla: A species with phenotypic plasticity in different climatic conditions

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    Berberis microphylla G. Forst., commonly called as "calafate" produces small fruits with high content of carbohydrates, phenols and antioxidants. The objective of this work was to characterize the vegetative and reproductive cycle of Berberis microphylla cultivated on Moreno (Buenos Aires province), Argentina in comparison with the results obtained in Ushuaia (Tierra del Fuego) which is its place of origin. Vegetative growth was very different in the two localities. Moreno plants grew with more lax branches than Ushuaia. In effect, length of the shoots was significantly higher for Moreno than Ushuaia plants. Flowering period in Ushuaia plants was concentrated in November while in Moreno it happens earlier and over a longer period. Pollen grains collected from Moreno flowers had a diameter of ~60 ÎĽm, significantly different to pollen grain from Ushuaia (57.11 ÎĽm). Nevertheless, pollen grain vitality was superior in Ushuaia flowers (75%) as compared to Moreno flowers (52%). On the other hand, fruit harvested in Moreno was at 60 days from full bloom while in Ushuaia plants at 120 days. Although the size and compounds measured in the fruits of Moreno were lower than those of Ushuaia, results obtained indicate that B. microphylla grown on Moreno is an interesting option to obtain another nutraceutical fruit near the centers of mass consumption.Fil: Radice, Silvia. Universidad de MorĂłn. Facultad de AgronomĂ­a y Ciencias Agroalimentarias; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; ArgentinaFil: Alonso, Marta. Universidad de MorĂłn. Facultad de AgronomĂ­a y Ciencias Agroalimentarias; ArgentinaFil: Arena, Miriam Elisabet. Universidad de MorĂłn. Facultad de AgronomĂ­a y Ciencias Agroalimentarias; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentin
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