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41.
ON THE EARLY GROWTH RATE OF THE INDIVIDUAL FUNGUS HYPHA 总被引:1,自引:0,他引:1
42.
C. TH. Buchelos C. G. Athanassiou C. CH. Papapostolou A. Georgiou 《Journal of Applied Entomology》1999,123(7):433-436
In order to evaluate the influence of the number of catches in pheromone-baited traps on the percentage of larval infestation, six delta traps equipped with sex attractant were placed in each of three regions in Central Greece (Farkadona, Farsala, Almyros) in cotton fields from 20 June until 30 September 1995. The collection of fruiting bodies took place weekly and the counting of adults in the traps was carried out each day. The population fluctuation in all three regions was similar with their peak during the first weeks of August. In Farkadona the infestation level was low (1% at the first sampling of August) with a maximum of 9% in the last sampling of September. In Farsala and Almyros, the infestation level was already high (10% and above) in early August. There was a significant positive linear correlation between the number of moth catches and the infestation percentage from first- and second-stage larvae on the first (R = 0694) and second (R = 0.7399) boll-feeding generations. 相似文献
43.
ALEXEY V. F. CH. BOBROV PETER K. ENDRESS ALEXANDER P. MELIKIAN MIKHAIL S. ROMANOV ALEXEY N. SOROKIN ALEJANDRO PALMAROLA BEJERANO 《Botanical journal of the Linnean Society. Linnean Society of London》2005,148(3):265-274
The indehiscent fruitlets of the apparently basalmost extant angiosperm, Amborella trichopoda, have a pericarp that is differentiated into five zones, a thin one‐cell‐layered skin (exocarp), a thick fleshy zone of 25–35 cell layers (outer mesocarp), a thick, large‐celled sclerenchymatous zone (unlignified) of 6–18 cell layers (middle mesocarp), a single cell layer with thin‐walled (silicified?) cells (inner mesocarp), and a 2–4‐cell‐layered, small‐celled sclerenchymatous zone (unlignified) derived from the inner epidermis (endocarp). The border between inner and outer mesocarp is not even but the inner mesocarp forms a network of ridges and pits; the ridges support the vascular bundles, which are situated in the outer mesocarp. In accordance with previous observations by Bailey & Swamy, no ethereal oil cells were observed in the pericarp; however, lysigenous cavities as mentioned by these authors are also lacking; they seem to be an artefact caused by re‐expanding dried fruits. The seed coat is not sclerified. The fruitlets of Amborella differ from externally similar fruits or fruitlets in other basal angiosperms, such as Austrobaileyales or Laurales, in their histology. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148 , 265–274. 相似文献
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Abstract: Many articulated brachiopods experience marked life habit variations during ontogeny because they experience their fluid environment at successively higher Reynolds numbers, and they can change the configuration of their inhalant and exhalant flows as body size increases. We show that the extant brachiopod Terebratalia transversa undergoes a substantial ontogenetic change in reorientation governed by rotation around the pedicle. T. transversa′s reorientation angle (maximum ability to rotate on the pedicle) decreases during ontogeny, from 180 degrees in juveniles to 10–20 degrees in individuals exceeding 5 mm, to complete cessation of rotation in individuals larger than 10 mm. Rotation ability is substantially reduced after T. transversa achieves the adult lophophore configuration and preferred orientation with respect to ambient water currents at a length of 2.5–5 mm. We hypothesize that the rotation angle of T. transversa is determined mainly by the position of ventral and dorsal points of attachment of dorsal pedicle muscles relative to the pedicle. T. transversa shows a close correlation between the ontogenetic change in reorientation angle and ontogeny of morphological traits that are related to points of attachment of dorsal pedicle muscles, although other morphological features can also limit rotation in the adult stage. The major morphological change in cardinalia shape and the observed reduction of rotation affect individuals 2.5–10 mm in length. The position of ventral insertions of dorsal pedicle muscles remains constant, but contraction of dorsal pedicle muscles is functionally handicapped because dorsal insertions shift away from the valve midline, rise above the dorsal valve floor, and become limited by a wide cardinal process early in ontogeny (<5 mm). The rate of increase of cardinal process width and of distance between dorsal pedicle muscle scars substantially decreases in the subadult stage (5–10 mm), and most of the cardinalia shell traits grow nearly isometrically in the adult stage (>10 mm). T. transversa attains smaller shell length in crevices than on exposed substrates. The proportion of small‐sized individuals and population density is lower on exposed substrates than in crevices, indicating higher juvenile mortality on substrates prone to grazing and physical disturbance. The loss of reorientation ability can be a consequence of morphological changes that strengthen substrate attachment and maximize protection against biotic or physical disturbance (1) by minimizing torques around the pedicle axis and/or (2) by shifting energy investments into attachment strength at the expense of the cost involved in reorientation. 相似文献
46.
J. Jordan P. Martin-Hirsch M. Arbyn U. Schenck J.-J. Baldauf D. Da Silva A. Anttila P. Nieminen W. Prendiville 《Cytopathology》2009,20(1):5-16
The current paper presents the second part of chapter 6 of the second edition of the European Guidelines for Quality Assurance in Cervical Cancer Screening . The first part of the same chapter was published in a previous issue ( Cytopathology 2008;19:342–54). This part provides guidance on how to manage and treat women with histologically confirmed cervical intraepithelial neoplasia. The paper describes the characteristics, indications and possible complications of excisional and ablative treatment methods. The three options to monitor the outcome after treatment (repeat cytology, HPV testing and colposcopy) are discussed. Specific recommendations for particular clinical situations are provided: pregnancy, immuno-suppression, HIV infection, post-menopause, adolescence and cyto-colpo-histological disparity. The paper ends with recommendations for quality assurance in patient management and some general advice on how to communicate screening, diagnosis and treatment results to the woman concerned. Finally, a data collection form is attached. 相似文献
47.
F. ORANGE F. WESTALL J.-R. DISNAR D. PRIEUR N. BIENVENU M. LE ROMANCER CH. DÉFARGE 《Geobiology》2009,7(4):403-418
Hydrothermal activity was common on the early Earth and associated micro‐organisms would most likely have included thermophilic to hyperthermophilic species. 3.5–3.3 billion‐year‐old, hydrothermally influenced rocks contain silicified microbial mats and colonies that must have been bathed in warm to hot hydrothermal emanations. Could they represent thermophilic or hyperthermophilic micro‐organisms and if so, how were they preserved? We present the results of an experiment to silicify anaerobic, hyperthermophilic micro‐organisms from the Archaea Domain Pyrococcus abyssi and Methanocaldococcus jannaschii, that could have lived on the early Earth. The micro‐organisms were placed in a silica‐saturated medium for periods up to 1 year. Pyrococcus abyssi cells were fossilized but the M. jannaschii cells lysed naturally after the exponential growth phase, apart from a few cells and cell remains, and were not silicified although their extracellular polymeric substances were. In this first simulated fossilization of archaeal strains, our results suggest that differences between species have a strong influence on the potential for different micro‐organisms to be preserved by fossilization and that those found in the fossil record represent probably only a part of the original diversity. Our results have important consequences for biosignatures in hydrothermal or hydrothermally influenced deposits on Earth, as well as on early Mars, as environmental conditions were similar on the young terrestrial planets and traces of early Martian life may have been similarly preserved as silicified microfossils. 相似文献
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49.
Schenck LW Kuna K Frank W Albert A Asche C Kucklaender U 《Bioorganic & medicinal chemistry》2006,14(10):3599-3614
1,4,9,10-Anthradiquinone 5 was reacted with enamines 6 in the Nenitzescu reaction to yield unexpected 3,3a,6,12-tetrahydro-3a,7-dihydroxy-2-methyl-6,12-dioxo-naphtho[2,3-d]indol-1-carboxylates 8A. However, anthracycline-like naphtho-condensed 5-hydroxyindoles were not obtained from this diquinone. It yielded similar reaction products of the Nenitzescu reaction like other quinones activated by two electron-withdrawing groups. Furthermore, these new compounds 8A were found to constitute precursors for the synthesis of azonines. The conversion to dibenzoazonines 13 occurred in an unusual and up to now unknown way consisting of isomerization, ring opening, and re-closure. 2-Chloro-anthradiquinone 19 reacted with enamines 6 as vinylogeous acid chloride to pyrroloanthraquinone 20. No substitution of chlorine was observed. Naphtho-condensed indoles 26 were obtained by the reactions of unsubstituted 1,4-anthraquinone 25 with enamines 6 via the normal Nenitzescu route. Indoles 26 were converted to Mannich bases, reacting further to dimers by the Diels-Alder reaction of intermediate o-quinone methides. Most of the synthesized heterocycles were evaluated for their anticancer properties in the NCI's human-disease oriented in vitro anticancer screen. Particularly, carbinolamines 8A exhibited inhibitory activity of tumor cell growth and thus they constitute a new class of lead structures for anticancer drug design. 相似文献
50.
Aurélien Bailly Bangjun Wang Marta Zwiewka Stephan Pollmann Daniel Schenck Hartwig Lüthen Alexander Schulz Jiri Friml Markus Geisler 《The Plant journal : for cell and molecular biology》2014,77(1):108-118
Plant growth is achieved predominantly by cellular elongation, which is thought to be controlled on several levels by apoplastic auxin. Auxin export into the apoplast is achieved by plasma membrane efflux catalysts of the PIN‐FORMED (PIN) and ATP‐binding cassette protein subfamily B/phosphor‐glycoprotein (ABCB/PGP) classes; the latter were shown to depend on interaction with the FKBP42, TWISTED DWARF1 (TWD1). Here by using a transgenic approach in combination with phenotypical, biochemical and cell biological analyses we demonstrate the importance of a putative C‐terminal in‐plane membrane anchor of TWD1 in the regulation of ABCB‐mediated auxin transport. In contrast with dwarfed twd1 loss‐of‐function alleles, TWD1 gain‐of‐function lines that lack a putative in‐plane membrane anchor (HA–TWD1‐Ct) show hypermorphic plant architecture, characterized by enhanced stem length and leaf surface but reduced shoot branching. Greater hypocotyl length is the result of enhanced cell elongation that correlates with reduced polar auxin transport capacity for HA–TWD1‐Ct. As a consequence, HA–TWD1‐Ct displays higher hypocotyl auxin accumulation, which is shown to result in elevated auxin‐induced cell elongation rates. Our data highlight the importance of C‐terminal membrane anchoring for TWD1 action, which is required for specific regulation of ABCB‐mediated auxin transport. These data support a model in which TWD1 controls lateral ABCB1‐mediated export into the apoplast, which is required for auxin‐mediated cell elongation. 相似文献