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71.
During observations in soybean fields, 136Neoscona arabesca (Walckenaer) and 46Tetragnatha laboriosa
Hentz were collected with prey. Significantly different prey compositions were recorded, withN. arabesca utilizing a large number ofColeoptera whileT. laboriosa captured primarilyHemiptera-Homoptera. Neoscona arabesca was observed to feed primarily in the evening following web construction, whileT. laboriosa fed predominantly in the morning. Although both of these species captured relatively large numbers of homopterans, most of
their prey were species which are not considered to be pests in soybean.
This paper (82-7-20) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director. 相似文献
Résumé Lors d'observations dans des champs de soja, 136Neoscona arabesca (Walckenauer) et 46Tetragnatha laboriosa Hentz furent recueillies avec leurs proies. Des différences significatives furent notées dans la composition des différents groupes de proies,N. arabesca capturant un grand nombre de Coléoptères tandis queT. laboriosa capture en premier lieu des Hémiptères (Hemiptera-Homoptera). Il fut observé queNeoscona arabesca se nourrit surtout dans la soirée qui suit la construction de la toile, alors queT. laboriosa se nourrit le plus souvent le matin. Bien que ces deux espèces aient capturé un nombre relativement important d'homoptères, la plupart de leurs proies étaient des espèces qui ne sont pas considérées comme nuisibles au soja.
This paper (82-7-20) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director. 相似文献
72.
Serologic and structural characterization of immunoglobulin chains secreted by rabbit-mouse hybridomas 总被引:3,自引:0,他引:3
M L Yarmush F T Gates K L Dreher T J Kindt 《Journal of immunology (Baltimore, Md. : 1950)》1981,126(6):2240-2244
Serologic and primary structural analyses of Ig chains secreted by several rabbit-mouse hybridomas have shown that these hybrid cells produce heavy (H) or light (L) chains identical to those isolated from rabbit sera. Two of the cell lines (7D2, 7D6) secreted rabbit H chains with a m.w. of 55,000 each of which expressed a full complement of variable and constant region allotypes (a3, d11, e15). These apparently normal rabbit H chains were secreted in a complex with a m.w. about 130,000, and serologic studies indicated that this complex contained a covalently linked mouse kappa L chain. Two other cell lines (4C1, 12F2) produced allotype b4 L chains with m.w. of 23,000 and 25,000, and a third (1D4P5) produced an allotype b5 L chain with a m.w. of 23,000. Serologic analyses indicated that the allotypes on these chains are equivalent to those expressed by normal rabbit Ig molecules. Partial amino acid sequence data obtained for the L chain products showed them to be typical of rabbit L chains, and to be significantly different from mouse L chains. 相似文献
73.
74.
75.
The ultrastructure of goose intestinal epithelial cells infected with various stages of E. kotlani has been described. No changes in the ultrastructure of the nucleus and cytoplasm were detected in cells, containing asexual stages. Damage of host cell structures, except Golgi complex, was not observed until gamogenesis. It is suggested that these changes are caused by the intensive "exploitation" of differentiated epithelial cells by large coccidian stages (macro- and microgametocytes). It is concluded that the epithelial cell of the goose, as of other animals, may function beyond crypts without the regulating influence of the nucleus. 相似文献
76.
77.
K. Reise 《Helgoland Marine Research》1979,32(4):453-465
The role of meiofauna in the trophic web of marine ecosystems is a controversial topic. During an experimental study on tidal flats in the eastern part of the North Sea, potential predators on meiofauna were kept in enclosures. A gobiid fish, shrimp, crabs, an amphipod, four polychaete worms and a nemertine were tested for their ability to decimate nematodes, turbellarians, ostracods and benthic copepods. Only few macrobenthic species preyed heavily on permanent meiofauna: juveniles of the shore crabCarcinus maenas, the hermit crabPagurus bernhardus with the colonial hydrozoanHydractinia echinata on its shells, and the rag wormNereis diversicolor. When benthic infauna was protected from these predators with exclosures, juvenile macrofauna responded with a marked increase in number, while the permanent meiofauna remained unaltered except for a limited increase in nematodes. It is concluded that in the Wadden Sea abundance of permanent meiofauna (Nematoda, Turbellaria, Ostracoda, Copepoda) is only locally or temporarily regulated by macrobenthic predators.I acknowledge a grant from the Deutsche Forschungsgemeinschaft (DFG). 相似文献
78.
K H Weisgraber T P Bersot R W Mahley 《Biochemical and biophysical research communications》1978,85(1):287-292
The singlet oxygen traps, 2,5-diphenylfurane and 1,3-diphenylisobenzofurane were oxidized to cis-benzoylethylene and o-dibenzoylbenzene during the decomposition of diisopropyl-N-nitrosamine catalyzed by peroxidase. Singlet oxygen quenchers inhibited this conversion and also the chemiluminescence accompaying the catalyzed reaction. The chemiluminescence is enhanced by 1,4-diazobicyclo (2.2.2) octane, fluorescein, eosin rhodamine B and rose bengal but little effect was detected in the presence of 9,10-dibromoanthracene-2-sulfonate, 9,10-diphenylanthracene-2-sulfonate and anthracene-2-sulfonate. An emission spectrum of the unsensitized reaction in 560 – 600 nm region was observed. It is concluded that singlet oxygen is formed during peroxidase catalyzed degradation of diisopropyl-N-nitrosamine. 相似文献
79.
Two new lecanid rotifers from India 总被引:5,自引:5,他引:0
B. K. Sharma 《Hydrobiologia》1978,60(2):191-192
While working on the material collected from Calcutta and its environs, the author came across two new lecanid rotifers which have been described in this paper as a new species and a new variety. 相似文献
80.
The fine structure of trophozoites and especially of merozoites of Babesia herpailuri is described before and after treatment with Imidocarb (Wellcome). The mostly piriform to oval merozoites possess an outer membrane and a supporting membrane below. The intratorium consists of a polar ring, rhoptries micronemes and the sperical body which lies beside the big nucleus and next to mitochondria. The endoplasmic reticulum and invaginations are not clearly formed. The cellular changes of Babesia herpailuri, observed one hour after drug treatment in trophozoites and six hours later in merozoites, concern the form and function of the parasite: widening of the subpellicular endoplasmic reticulum and of the perinuclear space; sporadic dilatation of the endoplasmic reticulum of the merozoites (9 fig.). Damaged membranes, dissolution of the cellular membrane, disintegration of the nuclei as are known effects of the Berenil treatment to Babesia herpailuri, are not noted results after the Imidocarb treatment. The original membrane systems of trophozoites as well as of merozoites, remain unaffected by the drug as long as investigations were carried on (24 h). The satisfying prophylactic effect of Imidocarb as well as the insignificant cellular damages on merozoites may be due to the small feeding of hemoglobin. 相似文献