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Bruno Hoste Lieve Luyten Ilse Claeys Elke Clynen Mazibur M. Rahman Arnold De Loof Michael Breuer 《Entomologia Experimentalis et Applicata》2002,104(2-3):281-288
In order to unravel the physiological, endocrine, and behavioral differences between gregarious and solitarious forms of the desert locust, Schistocerca gregaria (Forsk.) (Orthoptera, Acrididae), a constant supply of rather large numbers of solitary individuals has to be guaranteed. This represents a bottleneck, mainly because of the intensity of the labor involved and limited laboratory accommodation. The method we describe here substantially reduces the space and manpower needed. The survival rate we obtained in the solitarised population was relatively high, reaching about 55%. The optimal rearing temperature proved to be 32–36 °C. Cabbage leaves and oat flakes sufficed for feeding all year round. Special racks have been designed that enable high density stacking and easy handling. The solitarisation process was monitored over ten consecutive generations. Changes in morphometrics, eye stripes, color, and behavior were recorded, of which only morphometrics, temperature related development, and mortality are discussed. A shift towards the solitarious phase was recorded, with clear differences between gregarious, 1st generation and 7th to 10th generation solitarious locusts. 相似文献
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On the ecology of Trichocercidae (Rotifera) 总被引:2,自引:2,他引:0
A material consisting of 46 trichocercid rotifers from diverse waters in south and central Sweden was analyzed to reveal their relationships to their substrate. Most species were found in a wide variety of periphytic environments, but a few seemed to be specialized on bogs or psammon, respectively. Several trichocercids are generally regarded as plankters, but some of them obviously invade the open water only on certain occasions. A few species of Trichocerca are registered as indicators of eutrophy, but in some cases only a planktic occurrence may be regarded as indicating. On the other hand, hypertrophic environments are generally avoided. Trichocerca similis prefers polyhumic environments, T. uncinata oligotrophic and running-water conditions. The occurrence is often best explained by studying the food choice. 相似文献
77.
Rosa Angela Raccuglia Gabriella Bellone Kristina Loziene Franco Piozzi Sergio Rosselli Antonella Maggio Maurizio Bruno Monique S.J. Simmonds 《Phytochemistry》2010,71(17-18):2087-2091
From the aerial parts of Scutellaria hastifolia, family Lamiaceae (Labiatae), seven neo-clerodane diterpenoids (hastifolins A–G) were isolated. The products are similar to the known scuteparvin and are characterized by being trans-cinnamoyl derivatives. Structures and stereochemistry were determined by intensive NMR investigation. Six of the products form three pairs of epimers at C-13. Hastifolins A–C showed significant antifeedant activity. 相似文献
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Zavala-Ortiz Daniel Arturo Ebel Bruno Guedon Emmanuel Marc Annie Barradas-Dermitz Dulce María Hayward-Jones Patricia Margaret Aguilar-Uscanga María Guadalupe 《Bioprocess and biosystems engineering》2020,43(4):747-752
Bioprocess and Biosystems Engineering - Plant suspension culture is attracting interest as a promising platform to produce biological medicines due to the absence of virus, prions or DNA related to... 相似文献
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Juliana S. Maldarine Bruno D. A. Sanches Vitria A. Santos gata S. Cabral Maria L. D. Lima Carolina M. Bedolo Marília F. Calmon Paula Rahal Rejane M. Ges Patricia S. L. Vilamaior Sebastio R. Taboga 《Cell biology international》2020,44(6):1341-1352
The development and maintenance of prostate function depend on a fine balance between oestrogen and androgen levels. Finasteride inhibits 5α‐reductase, which is responsible for the conversion of testosterone into its most active form, dihydrotestosterone. Enzymes that metabolize these hormones have a highly relevant role in both the normal prostate metabolism and in the occurrence of pathological conditions. There are few studies on the impact of finasteride on male prostate development and fewer studies on the female prostate and possible intersexual differences. Therefore, we treated male and female gerbils from 7 to 14 days in postnatal life with a high dose of finasteride (500 μg/kg/day); the prostate complexes were then removed and submitted to immunohistochemistry, immunofluorescence and three‐dimensional reconstruction. In addition, hormonal serum dosages were administered. Treatment with finasteride resulted in an increased thickness of the periductal smooth musculature in the prostate of both male and female gerbils, such as well as a reduction in the thickness of developing prostate alveoli in both sexes. In addition, intersexual differences were observed as increased epithelial proliferation and decreases in the number of developing alveoli in females. Together, the data indicate that postnatal exposure to finasteride causes greater changes in the female gerbil prostate than in the male. 相似文献