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The lipid class and fatty acid (FA) composition of juvenile Artemia fed continuously on four diets—the microalga Tetraselmis suecica , a mix of oat bran-wheat germ-lecithin (OWL), OwL-eicosapentaenoic acid (EPA), and OWL-EPA-arachidonic acid (AA)—were examined over a 9-d experiment in an attempt to approximate the FA profile of phyllosoma larvae of wild southern rock lobster Jasus edwardrii . The main difference in lipid class composition of Artemia fed the four diets was the relative level of polar lipid (PL) and triacylglycerol (TAG). By day 9, the algal-fed Artemia were highest in PL (95% of total lipid) and lowest in TAG (2%), whereas the remaining diets resulted in Artemia with 16–30% PL and 41–82% TAG. After 2 d, the relative FA composition of all Artemia treatments closely reflected those of the diets, with no marked change after further feeding (to day 9). In terms of the content of essential polyunsaturated fatty acids (PUFA), by day 5 Artemia fed: 1) with the algal diet contained 7 mg/g FA dry mass (0.3% DHA, 6.3% EPA, 3.4% AA of total FA); 2) with the OWL diet contained 3 mg/g (0.3% DHA, 0.9% EPA, 0.7% AA); 3) with the OWL-EPA diet contained 55 mg/g (6.2% DHA, 11.6% EPA, 1.1% AA); and 4) with the OWL-EPA-AA contained 83 mg/g (3.8% DHA, 7.5% EPA, 17.4% AA). The PUFA profiles of Artemia using the OWL-oil diets were similar to wild rock lobster phyllmmata, although levels of doco-sahexaenoic acid (DHA) were lower (10% DHA) than in J. edwardsii larvae. On the basis of PUFA composition data alone, the results suggest the suitability of the OWL-oil mixed diets for consideration for feeding to Artemia used in the culture of southern rock lobster larvae, particularly if the level of DHA can be further enhanced.  相似文献   
3.
Ninety-seven pure-bred Akitas were examined clinically and histologically for sebaceous adenitis. The diagnosis was established histologically in 23 Akitas by demonstrating an inflammatory reaction targeted against the sebaceous glands or a reduction in the number of glands. The clinical course of sebaceous adenitis in the Akita was similar to that seen in other breeds. The first skin lesions occurred mainly on the dorsal midline and ears. Compared with the Poodle, the age at first onset of the disease was more variable and the hair loss affected mainly the undercoat. The progression of sebaceous gland destruction varied between dogs and was not seen in all cases. Because bud-like sebaceous gland proliferation could be identified, it seems that regeneration of the sebaceous glands may occur. An autosomal recessive inheritance appears to be possible. Apart from a genetic background, immune-mediated factors possibly influence the onset and course of sebaceous adenitis.  相似文献   
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Papillomaviruses (PVs) are highly species- and site-specific pathogens of stratified squamous epithelium. Although PV infections in the various Felidae are rarely reported, we identified productive infections in six cat species. PV-induced proliferative skin or mucous membrane lesions were confirmed by immunohistochemical screening for papillomavirus-specific capsid antigens. Seven monoclonal antibodies, each of which reacts with an immunodominant antigenic determinant of the bovine papillomavirus L1 gene product, revealed that feline PV capsid epitopes were conserved to various degrees. This battery of monoclonal antibodies established differential expression patterns among cutaneous and oral PVs of snow leopards and domestic cats, suggesting that they represent distinct viruses. Clinically, the lesions in all species and anatomic sites were locally extensive and frequently multiple. Histologically, the areas of epidermal hyperplasia were flat with a similarity to benign tumors induced by cutaneotropic, carcinogenic PVs in immunosuppressed human patients. Limited restriction endonuclease analyses of viral genomic DNA confirmed the variability among three viral genomes recovered from available frozen tissue. Because most previous PV isolates have been species specific, these studies suggest that at least eight different cat papillomaviruses infect the oral cavity (tentative designations: Asian lion, Panthera leo, P1PV; snow leopard, Panthera uncia, PuPV-1; bobcat, Felis rufus, FrPV; Florida panther, Felis concolor, FcPV; clouded leopard, Neofelis nebulosa, NnPV; and domestic cat, Felis domesticus, FdPV-2) or skin (domestic cat, F. domesticus, FdPV-1; and snow leopard, P. uncia, PuPV-2).  相似文献   
6.
Performance of phyllosoma of thesouthern rock lobster (Jasus edwardsii)was examined after feeding Artemia-baseddiets. Survival and growth of newly-hatchedlarvae cultured to Stage III were lower(p < 0.05) when fed 0.8 mm Artemia than1.5 mm or 2.5 mm Artemia alone or 1.5 mmArtemia in combination with pieces ofmussel (Mytilus edulis planulatus) gonad.This could not be attributed to deficiencies inthe composition of fatty acids but appeared tobe due to the inability of larvae to capturesufficient appropriate-sized, enrichedArtemia for their nutritional requirements.There was an indication that survival andgrowth were higher between Stages III and Vwhen fed 2.5 mm Artemia than 1.5 mmArtemia alone or in combination with musselpieces. However, Stage VI larvae grew to asimilar size at Stage VIII when fed 1.5 mm or2.5 mm Artemia. Unexpectedly, larvae fedthe combination of 1.5 mm Artemia plusmussel supplement had lower survival than foundpreviously, and generally lower than when fed 1.5 mm Artemia alone. This was despitean apparent nutritional profile (lipid contentand fatty acid composition) of mussel more akinto that of newly-hatched phyllosoma thanenriched Artemia. On the other hand,survival and growth to Stage VIII were higherwhen larvae were fed alginate pelletscontaining Artemia than when fed 1.5 mmor 2.5 mm Artemia alone.  相似文献   
7.
Fermi liquid theory, the standard theory of metals, has been challenged by a number of observations of anomalous metallic behavior found in the vicinity of a quantum phase transition. The breakdown of the Fermi liquid is accomplished by fine-tuning the material to a quantum critical point by using a control parameter such as the magnetic field, pressure, or chemical composition. Our high-precision magnetization measurements of the ultrapure f-electron-based superconductor β-YbAlB(4) demonstrate a scaling of its free energy that is indicative of zero-field quantum criticality without tuning in a metal. The breakdown of Fermi liquid behavior takes place in a mixed-valence state, which is in sharp contrast with other known examples of quantum critical f-electron systems that are magnetic Kondo lattice systems with integral valence.  相似文献   
8.
Large numbers of shoots have been obtained from the excised basal regions of leek plants, cultured on BDS medium. Shoots could be induced optimally upon media within the range of 6.0–8.0 mg 1?1 6-(3-methyl-2-buten-1-ylamino)-purine (2iP) and 1.0–2.0 mg 1?1 napthaleneacetic acid (NAA). Sub-culture of induced shoots onto fresh media, from the above hormone ranges, resulted in further multiplication. Sub-culture, onto fresh medium from the above hormone ranges, of the callus-like region around the bases of induced shoots and adjacent tissue, could also result in shoot production. Internally developing shoot primordia occurred in close proximity to meristematic regions, whereas superficially developing primordia did not show distinct affinities, although there was evidence of localised pockets of meristematic cells amidst senescing explant material at the surface of the culture. Such regions may represent early stages in the formation of the superficial primordia. The production of large numbers of leek shoots in vitro is mentioned in relation to present techniques of micro-propagation and cryopreservation.  相似文献   
9.
Synovial chondrometaplasia was diagnosed in 5 dogs. Four dogs improved dramatically after surgical removal of subsynovial nodules, but the fifth improved only slightly. This potentially treatable condition is recognized in human beings, and has been described in dogs in the German scientific literature. Synovial chondrometaplasia should be suspected if numerous joint mice are visualized radiographically, without an obvious inciting cause. It also should be suspected when periarticular osteophytes are found radiographically in unusual locations.  相似文献   
10.
Shoots have been produced on callus derived from onion set and from seedling radicle tissue. Whilst callus of set origin responded optimally to medium containing the cytokinin 6-(3-methyl-2-buten-1-ylamino)-purine (2iP) at 2.00 mg l?1 and naphthaleneacetic acid (NAA) at 0.06 mg l?1, seedling radicle callus showed a range of response. The medium used for callus initiation, the age of callus, and the provision of a dark period following inoculation on to the organogenesis medium have been shown to be critical for shoot formation. A limited number of embryoids have been produced from cultures; their occurrence was usually associated with an increase in shoot numbers for the generative callus tissue. Meristemoid areas have been observed in light micrographs of callus cultured upon organogenesis media.  相似文献   
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