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1.
A combined ultracentrifugation and precipitation technique was used to quantify the plasma lipoprotein concentrations of control dogs (n=33) and dogs with diabetes mellitus (n=11), hyper-adrenocorticism (n=14), hypothyroidism (n=10) and obesity (n=20). In addition, the effect of breed type, age and gender on the lipoprotein phenotype was assessed. Breed type and age were found to have no effect upon cholesterol and lipoprotein concentrations but the high density lipoprotein cholesterol (HDL-C) concentration was greater in intact females than intact males. Cholesterol concentrations were significantly higher than those of the control group in dogs with diabetes mellitus (P<0·01), hyper-adrenocorticism (P<0·01) and hypothyroidism (P<0·001). In dogs with diabetes mellitus this was due to increased concentrations of very low density lipoprotein cholesterol (VLDL-C) (P<0·01) and HDL-C (P<0·05). The concentrations of low density lipoprotein cholesterol (LDL-C) (P<0·05) were significantly increased in dogs with hyperadrenocorticism, while in the hypothyroid dogs, VLDL-C (P<0·05), LDL-C (P<0·001) and HDL-C (P<0·05) were significantly higher than the control group. The cholesterol and lipoprotein concentrations in the obese population were not significantly different from control dogs.  相似文献   
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Although most of the magnetic flux observed on the sun originates in the low-latitude sunspot belts, this flux is gradually dispersed over a much wider range of latitudes by supergranular convective motions and meridional circulation. Numerical simulations show how these transport processes interact over the 11-year sunspot cycle to produce a strong "topknot" polar field, whose existence near sunspot minimum is suggested by the observed strength of the interplanetary magnetic field and by the observed areal extent of polar coronal holes. The required rates of diffusion and flow are consistent with the decay rates of active regions and with the rotational properties of the large-scale solar magnetic field.  相似文献   
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Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR.  相似文献   
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The primate fauna of South Africa has historically been viewed as comprising three diurnal cercopithecoid taxa – chacma baboons (Papio ursinus), vervet (Chlorocebus pygerythrus) and samango monkeys (Cercopithecus albogularis) – and two nocturnal lorisoid species – the thick-tailed greater galago (Otolemur crassicaudatus) and the southern lesser galago (Galago moholi). Here we report the positive identification of a third galago species within South Africa’s borders: the Mozambique dwarf galago or Grant’s galago, Galagoides granti (Thomas and Wroughton, 1907). The taxon was previously held to be restricted to Mozambique, eastern Zimbabwe, Malawi and Tanzania, but we have also observed it in the sand forest of Tembe Elephant Park and the Tshanini Community Reserve, near the Mozambique border. The species was formerly mistaken for Galago moholi, erroneously (we believe) extending the range of the latter species into northern KwaZulu-Natal. In South Africa the two small galagos are unlikely to have overlapping ranges: Galago moholi prefers dry savanna woodlands, whereas Galagoides granti is apparently confined to dry sand forest. However, both species may coexist with the larger and more widespread Otolemur crassicaudatus, an inhabitant of moist savanna, forest edge and thicket. The true South African ranges of both small galago species need to be ascertained.  相似文献   
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Cokeromyces recurvatus, a zygomycete, was isolated by fungal culture from the peritoneal fluid of a cat with jejunal perforation secondary to intestinal lymphosarcoma. This organism has not been recovered previously from a veterinary patient. The tissue form of C. recurvatus is morphologically similar to those of Coccidioides immitis and Paracoccidioides brasiliensis and may be misdiagnosed as 1 of these organisms on the basis of cytologic or histopathologic specimens, particularly in geographic regions where these organisms are not endemic.  相似文献   
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Lentigines were seen on the head and trunk of a 4-year-old 4-kg domestic silver shorthair cat. Excisional biopsy specimens were obtained to confirm lentigo simplex. The lentigo lesions were similar to those described in orange, cream, red, and tri-colored cats; however, the coloring of this cat and diffuse distribution of lesions were unusual.  相似文献   
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