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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 41 (1985), S. 1028-1034 
    ISSN: 1420-9071
    Keywords: Cockroach ; Diploptera punctata ; juvenile hormone titre ; juvenile hormone half-life ; juvenile hormone release rate ; gonotrophic cycle ; allatectomy ; nonhemolymph juvenile hormone pool
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Titres of juvenile hormone (JH) have been determined in both hemolymph and whole body extracts of femaleDiploptera punctata during the first gonotrophic cycle using a method employing gas chromatography/mass spectrometry for qualitative and quantitative analysis. JH III is the sole JH found in both adult and last instarD. punctata. Maximum values of ∼ 1500 ng/ml (∼6μM) were observed at the middle of the gonotrophic cycle, when basal oocyte growth rate was greatest. Changes in rates of JH release in vitro by corpora allata paralleled closely the changes in JH titre, suggesting that biosynthesis is a major regulator of titre. JH levels per animal were calculated from observed JH titres, and at certain time points in the gonotrophic cycle JH levels obtained from analysis of whole bodies were significantly greater than those predicted from hemolymph titres. These results suggest the existence of a nonhemolymph JH pool inD. punctata. Decay in JH titre after allatectomy of 5 day females has also been studied. Following a rapid initial decline, the rate of decay slowed appreciably 4 h post-operation. Thus, use of a first-order rate constant to estimate half-life of JH significantly underestimated the longevity of the hormone. The apparent persistence of JH following allatectomy may be due to the existence of a nonhemolymph JH pool.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Entomology 23 (1978), S. 283-307 
    ISSN: 0066-4170
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Résumé Nous avons comparé in vitro dans les corpora allata de femelles adultes de sauterelles (Schistocerca gregaria) et de cafards (Periplaneta americana) le taux de composition de la méthyl farnesoate marquée et son epoxydation due à l'hormone juvénile C16. Chez les sauterelles, un surcroît d'acide farnésique stimule l'estérification et l'époxydation, tandis que chez les cafards, une accumulation de méthyl farnesoate dans les glandes et l'indice d'une saturation de l'enzyme oxygénase. Cette contenance oxydative plus basse des glandes de cafard est en rapport avec leur trachéolation peu abondante.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 30 (1974), S. 517-518 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Résumé Quand les mouches tsétsé (Glossina austeni) se nourrissent de sang contenant du3H2O et du14C-dextran, le3H2O réapparaît après 5 min dans l'urine à des concentrations qui se rapprochent de celles de son absorption. La concentration du3H2O dans l'hémolymphe est nettement moins élevée que dans l'urine. Le14C-dextran est présent au moins dans l'urine des mouches. Ces résultats suggèrent un compartimentage de l'eau durant la diurèse, ce qui prévient la dilution de l'hémolymph.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 33 (1977), S. 343-345 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The location of the terminal oocytes (T) in the ovary of the desert locust dictates whether the penultimate oocytes (T-1) will enter vitellogenesis — as long as the T oocytes are retained within the ovarioles, vitellogenesis in T-1 oocytes is prevented. When the T oocytes are ovulated into the oviduct, growth of the T-1 oocytes (new T) resumes. Inhibition of vitellogenesis in T-1 oocytes is not due to low rates of JH biosynthesis since high rates of JH biosynthesis were observed in animals in which T oocytes were retained in the ovarioles.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 39 (1983), S. 1329-1334 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Control of the corpora allata (CA) ofDiploptera punctata is maintained by at least 2 factors. The glands are directly inhibited by an allatostatin arriving at the CA via the nervi corporis cardiaci I (NCC I). Destruction of the putative source (median neurosecretory cells, MNC) of the allatostatin by radio-frequency (RF) cautery relieved the inhibition imposed on the CA of virgin females, and the glands became active. Similarly, destruction of the lateral neurosecretory cells (LNC) also relieved the inhibition. We propose that the LNC stimulated the MNC to release allatostatin. RF-cautery did not result in the activation of CA of pregnant or ovariectomized females. Activation of the CA may therefore require not only absence of the inhibitory factor but also the presence of a stimulatory one (perhaps from the ovary).
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 281 (1979), S. 481-482 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Mated females of Diploptera punctata were allatectomised between 1 and 5 h after adult ecdysis9. Three to four days later, the JH analogue ZR512 (ethyl (2E, 4£)-3,7,1 l-trimethyl-2,4-dodecadienoate, Zoecon) was applied in 5 ? of acetone to the dorsal surface of the abdomen (wings were ...
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 268 (1977), S. 728-730 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] To determine the effect of nerve section on JH biosynthesis, the NCA 1 to each CA was severed at selected times during the first gonotrophic cycle of female locusts. After nerve section, locusts were maintained for up to 4 d in standard rearing conditions11 before assaying the rate of biosynthesis ...
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 252 (1974), S. 474-476 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Up to now the activity of the corpus allatum has been inferred from indirect observations such as glandular activity after transplantation into a suitable host animal9, gland extirpation plus hormone replacement therapy10 and measurement by bioassay of apparent titres of juvenile hormone in the ...
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1432-203X
    Keywords: Key words Cyperus iria L. ; Juvenile hormone III ; Methyl farnesoate ; Callus ; Suspension culture
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Juvenile hormones (JHs) are sesquiterpenoids that regulate metamorphosis and reproduction in most insect species. There has been one report of an insect JH in plants: JH III, methyl-10R,11-epoxy-3,7,11-trimethyl 2E, 6E-dodecadienoate, has been identified in two sedge species, Cyperus iria L. and C. aromaticus (Ridley) Mattf and Kük. This is the first report of callus and cell suspension cultures derived from C. iria. Farnesol and methyl farnesoate, two biosynthetic intermediates of JH III in insects, as well as JH III have been identified in suspension culture cell extracts by gas chromatography-mass spectroscopy. These cultures thus provide a useful in vitro model to investigate the biosynthesis of JH III in the sedge, C. iria.
    Type of Medium: Electronic Resource
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