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61.
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64.
Hans Horst Meyer 《Die Naturwissenschaften》1934,22(36):598-601
65.
66.
Kurt H. Meyer 《Die Naturwissenschaften》1927,15(6):129-134
67.
Ingeborg L. A. Boxman 《Food and environmental virology》2010,2(3):156-166
Different sources were consulted to obtain information on the occurrence of viruses in bivalve molluscs on the European market.
Twenty-six peer-reviewed articles were identified reporting on the molecular detection of viral RNA in 4,260 samples in total.
The data obtained will be presented geographically on virus types detected, the origin and treatment of the shellfish, and
the detection technique applied. The data demonstrate that viral RNA can be detected in shellfish from polluted areas, in
depurated shellfish as well as those for human consumption. The European Rapid Alert System for Food and Feed (RASFF) database
was consulted as another source. Twenty-eight notifications were identified on the presence of hepatitis A virus or norovirus
in shellfish on the European market. The most recent report of the European laboratory network was referred to, to gain insight
into the laboratory capability at present for the analyses of shellfish on the presence of viruses. Approximately 67% of 27
participating laboratories obtained intended results for all samples, consisting of lenticules loaded with 103 copies norovirus (genogroup I (GGI) and/or genogroup II (GGII)) and/or 1 × 105–8 × 104 copies of hepatitis A virus. From 1993, there has been a continuous development of molecular detection techniques and tools
have been described to ensure quality assurance. End product testing will, however, not be achievable. As depuration has been
shown not to be effective for the complete elimination of viruses, shellfish should not be in contact with faecal contaminated
water in order to minimise the risk of shellfish-transmittable viral diseases. 相似文献
68.
Both phytophagous and parasitic insects deposit oviposition-marking pheromones (OMPs) following oviposition that function
to inform conspecifics of a previously utilized host of reduced suitability. The blueberry maggot fly, Rhagoletis mendax Curran (Diptera: Tephritidae), deposits eggs individually into blueberries and then marks the fruit surface with an OMP which
reduces acceptance of fruit for oviposition by conspecifics. Diachasma alloeum (Muesebeck) (Hymenoptera: Braconidae) is a parasitic wasp attacking larval R. mendax which also deposits an OMP, signaling conspecifics of a wasp-occupied host. Behavioral studies were conducted testing the
hypothesis that the OMP of the parasitic wasp modifies the oviposition behavior of its host fly. In this study, we show that
the OMP of D. alloeum is recognized by R. mendax, and female flies will reject wasp-marked fruit for oviposition. Thus, we present a rare demonstration of pheromonal recognition
between animals occupying different taxonomic orders and trophic levels. This chemical eavesdropping may enhance the ability
of the fly to avoid fruit unsuitable for larval development. 相似文献
69.
The giant clam Tridacna crocea harbors in the mantle tissue symbiotic microalgae commonly called zooxanthellae. Isolated zooxanthellae release glycerol
into the medium in the presence of mantle tissue homogenate (MH), but it is not clear whether the cells do so in situ. In
order to determine the photosynthetic products released by zooxanthellae in the mantle of the giant clam we traced photosynthetic
fixation products from 13C- and 14C-bicarbonate both in the clam and in isolated zooxanthellae (IZ) in the presence or absence of MH. After 15 min incubation
in the absence of MH the IZ released less than 0.6% of the fixed labeled carbon, mainly as glucose. The major intracellular
photosynthates were neutral lipids, which constituted 20 to 40% of the total extractable 14C. In the presence of MH, the IZ released up to 5.6% of the total fixed 14C, mostly as glycerol, and the major intracellular photosynthate was glucose. In an intact clam incubated in sea water containing
14C-bicarbonate, 46 to 80% of the fixed 14C was translocated from the zooxanthellae to the host tissues. Most of the 14C in the hemolymph, in the isolated zooxanthellae and in intact mantle tissue (containing zooxanthellae) was recovered as
glucose. No 14C-glycerol was detected in the mantle after 1 to 30 min incubation, and, even after 60 min, far less 14C-glycerol was synthesized than by IZ in the presence of MH. The possibility that in clam tissue glycerol is converted to
glucose was examined by tracing the labeled carbon from 14C-glycerol injected into the adductor muscle. After 5 min incubation, no labeled glucose was found in the hemolymph, but after
60 min, some 20% was found as glucose. Thin slices containing zooxanthellae, cut from the surface of the mantle, fixed inorganic
carbon supplied as NaH14CO3 in the medium and mainly released 14C-glucose. The addition of MH to the surrounding medium did not affect the release rate or form of release product. When the
slices were cut into smaller pieces, however, the ratio of glycerol to glucose in the release product increased. These results
indicate that in the presence of MH the metabolism of isolated zooxan- thellae was different from that of zooxanthellae in
the mantle. In the presence of MH, isolated zooxanthellae release mostly glycerol, whereas in the mantle they release glucose.
Received: 18 February 1998 / Accepted: 4 December 1998 相似文献
70.
We equipped individual tiger (Galeocerdo cuvier Péron and Lesueur, 1822) and Galapagos (Carcharhinus galapagensis Snodgrass and Heller, 1905) sharks with both acoustic and satellite transmitters to quantify their long-term movements in
the Papahanaumokuakea Marine National Monument (Northwestern Hawaiian Islands). Tiger sharks exhibited two broad patterns
of behavior. Some individuals were detected at French Frigate Shoals (FFS) year round, whereas others visited FFS atoll in
summer to forage on fledging albatross, then swam thousands of kilometers along the Hawaiian chain, or out into open ocean
to the North Pacific transition zone chlorophyll front, before returning to FFS in subsequent years. These patterns suggest
tiger sharks may use cognitive maps to navigate between distant foraging areas. Different patterns of spatial behavior may
arise because cognitive maps are built up through individual exploration, and each tiger shark learns a unique combination
of foraging sites. Galapagos shark detections were all associated with FFS, suggesting these sharks may be more resident around
oceanic islands. Both Galapagos and tiger sharks primarily used the mixed layer (<100 m depth) and made occasional deeper
dives through the thermocline down to 680 m. Results show reef-associated sharks utilize a wide variety of habitats ranging
from shallow atoll lagoons to deep reefs and open ocean and may provide important trophic links between these habitats. 相似文献