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191.
Hadley NF 《Science (New York, N.Y.)》1979,203(4378):367-369
The desert beetle Cryptoglossa verrucosa(LeConte) exhibits distinct color phases that range from light blue to jet black when subjected to extremes of low and high humidity, respectively. The color phases are created by "wax filaments" that spread from the tips of miniature tubercles that cover the cuticle surface. The meshwork that accumulates at low humidity reduces transcuticular water loss and may lower the rate at which body temperature rises under a radiation load by increasing reflectance. 相似文献
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Freeman DA Cymbaluk NF Schott HC Hinchcliff K McDonnell SM Kyle B 《American journal of veterinary research》1999,60(11):1445-1450
OBJECTIVE: To compare health, hydration status, and management of stabled pregnant mares provided drinking water continuously or via 1 of 3 intermittent delivery systems. ANIMALS: 22 Quarter Horse (QH) or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 1); 24 QH or QH-crossbred mares and 18 Belgian or Belgian-crossbred mares (study 2). PROCEDURE: Stabled horses were provided water continuously or via 1 of 3 intermittent water delivery systems in 2 study periods during a 2-year period. Body temperature, attitude, appetite, water intake, and urine output were recorded daily. Hygiene of each horse and the stable were assessed weekly. Clinical and biochemical measures of hydration were determined 3 times during each study. Clinical measures of hydration included skin turgor, gum moisture, capillary refill time, and fecal consistency. Biochemical measures of hydration included PCV, plasma total protein concentration, serum osmolality, plasma vasopressin concentration, urine specific gravity, and urine osmolality. RESULTS: All horses remained healthy. Stable hygiene was worse when horses had continuous access to water. Clinical and biochemical measures of hydration did not differ among water delivery systems. CONCLUSIONS AND CLINICAL RELEVANCE: Various continuous and intermittent water delivery systems provided adequate amounts of water to stabled horses to maintain health and hydration status. Providing intermittent access to water may be preferable on the basis of stable hygiene. 相似文献
195.
Rodríguez NF Tejedor-Junco MT Hernández-Trujillo Y González M Gutiérrez C 《Veterinary parasitology》2010,174(3-4):323-327
Trypanosoma evansi was diagnosed for the first time in camels in the Canary Islands in 1997. Several sanitary measures including treatment of infected animals were taken; however, nowadays a little area is still infected. In order to determine possible reservoirs 138 wild rodents were trapped, 64 of them in the infected farms and the remaining 74 in other areas. The captured species were Rattus rattus (24), Rattus norvegicus (69) and Mus musculus domesticus (45). Serological (CATT/T. evansi), parasitological (micro-Hematocrit Centrifugation technique and stained smears) and molecular (PCR) methods for T. evansi and T. lewisi were used as diagnostic methods. None of the examined rodents was positive for T. evansi; 18, however, showed motile trypanosomes at micro-Hematocrit Centrifugation technique and resulted positive for T. lewisi by PCR. The results would suggest that the studied rodent species would not play a relevant role in the epidemiology of T. evansi infection in Canaries. 相似文献
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Fletcher NF Brayden DJ Brankin B Callanan JJ 《Veterinary immunology and immunopathology》2008,123(1-2):134-137
Feline immunodeficiency virus (FIV), like human immunodeficiency virus (HIV)-1, is a neurotropic lentivirus and is associated with neuropathology in natural and experimental infections. FIV enters the brain early following experimental infection, and virus has been proposed to enter the brain via the blood–brain barrier and blood–CSF barrier, within infected lymphocytes and monocytes/macrophages. However the entry of cell-free virus or the direct infection of brain endothelial cells and astrocytes of the blood–brain barrier may also contribute to CNS infection. This review explores the role played by the FIV model in the elucidation of mechanism of lentiviral entry to the brain and viral interactions with the CNS, particularly in relation to lymphotropic lentiviruses. 相似文献
199.
Secretion of gastric mucins plays an essential role in host protection, and modifications in mucus properties are characteristic of the protective immune responses to pathogens. This study describes the purification and characterisation of sheep gastric mucins, and identification of those proteins that co-purify with mucins, with the potential to modify mucus properties. Gastric mucus was collected and pooled from four abattoir sheep and separated by CsCl density gradient centrifugation. Proteomic analysis of the mucin-containing fraction indicated the presence of gastric mucin (Muc5ac) and several co-purifying proteins, including intelectin-2 (Itln2). Further experimentation indicated that a combination of denaturation and reduction was required to fully release Itln2 from gastric mucin. A putative correlation was found between mucin-bound intelectin concentration and rheological properties in further sheep gastric mucus samples. In conclusion, this study provides the first characterisation of sheep gastric mucins and their purification partners, revealing potentially important mucin-intelectin interactions. 相似文献
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