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Eighteen clinically ill dogs, naturally infected with Anaplasma phagocytophilum, were examined at a veterinary practice in Baxter, Minnesota. A clinical examination, complete blood cell count, enzyme- linked immunosorbent assay (ELISA) for A phagocytophilum, Borrelia burgdorferi, and Ehrlichia canis antibodies and Dirofilaria immitis antigen, and a polymerase chain reaction test for A phagocytophilum DNA were obtained for all dogs. Physical examination findings included fever, arthropathy, lymphadenopathy, epistaxis, acute gastritis, cervical hyperpathia, and central nervous system dysfunction. Complete blood cell count abnormalities included thrombocytopenia, morulae in neutrophils, anemia, leukopenia, eosinopenia, lymphopenia, and monocytosis. Seroreactivity to A phagocytophilum was found in 61%, B burgdorferi antibodies in 17%, and D immitis antigen in 5% of the dogs. Fever, arthropathy, neurologic dysfunction, and epistaxis are clinical syndromes that can be associated with A phagocytophilum infection. Treatment with doxycycline resulted in rapid resolution of clinical signs in all dogs.  相似文献   
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The histamine 4 (H4) receptor was first cloned and characterized in 2000 using the human H3 receptor DNA sequence. The H4 receptor has been shown to participate in various aspects of inflammation, such as chemotaxis, upregulation of adhesion molecule expression and modulation of cytokine secretion. The primary goal of this study was to determine whether H4 receptor mRNA is expressed in normal canine skin by performing an RT‐PCR. An additional goal was to determine the expression of this receptor in the colon, liver, spleen and kidney. Tissues were collected from five healthy, young‐adult pit bull dogs. Samples were immediately placed in RNAlater® solution and stored at ?20°C until processed. The amplified products in all skin samples in addition to the colon, liver, spleen and kidney (variable expression) had the expected size of 400–500 bp. The sequenced amplicons matched the National Center for Biotechnology Information published sequence for the canine H4 receptor. The study results showed that canine normal skin expresses the H4 receptor mRNA. Further studies using immunohistochemistry should be conducted to demonstrate the expression of the H4 receptor at the protein level and to localize the expression of this receptor in the skin.  相似文献   
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Individuals that inhabit broad elevational ranges may experience unique environmental challenges. Because temperature decreases with increased elevation, the ectotherms living at high elevations have to manage limited activity time and high thermoregulatory effort. The resting metabolic rate (RMR) of a postabsorptive animal is related to its total energy requirements as well as many other fitness traits. Mesquite lizards (Sceloporus grammicus) living on La Malinche Volcano, Mexico, inhabit a wide elevational range with some populations apparently thriving above the tree line. We measured the RMR of lizards from different elevations (i.e., 2,600, 3,200, and 4,100 m) at four ecologically relevant temperatures (i.e., 15, 25, 30, and 35 °C) and found that RMR of mesquite lizards increased with temperature and body mass. More importantly, lizards from the high‐elevation population had mass specific RMR that was higher at all temperatures. While the higher RMRs of high‐elevation populations imply higher metabolic costs at a given temperature these lizards were also smaller. Both of these traits may allow these high elevation populations to thrive in the face of the thermal challenges imposed by their environment.  相似文献   
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Leersia oryzoides (rice cutgrass) is an obligate wetland plant common to agricultural drainage ditches. The objective of this greenhouse study was to expose plants to various flooding and aqueous nitrogen (N) concentrations and then to quantify the allocation of nutrients and biomass to plant components. Plants in the continuously flooded treatment (CF) had the highest tissue concentrations of copper (Cu), sulfur (S), zinc (Zn), potassium (K), sodium (Na), and manganese (Mn) in one or more plant components. Plants in the partially flooded treatment (PF) had the highest concentrations of magnesium (Mg) in leaves. The N input affected phosphorus (P) and S concentrations in roots. Leaf, stem, and root biomass were highest in PF plants. Rhizome biomass was the lowest in CF plants. These results indicate that L. oryzoides may significantly affect elemental concentrations in surface waters by its ability to uptake various elements and subsequent sequestration in various biomass components.  相似文献   
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Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world, and it causes substantial physical and functional impact. It produces a myriad of gastrointestinal, neurologic and/or cardiovascular symptoms which last days to weeks, or even months. Although there are reports of symptom amelioration with some interventions (e.g. IV mannitol), the appropriate treatment for CFP remains unclear to many physicians. We review the literature on the treatments for CFP, including randomized controlled studies and anecdotal reports. The article is intended to clarify treatment options, and provide information about management and prevention of CFP, for emergency room physicians, poison control information providers, other health care providers, and patients.  相似文献   
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Plant Foods for Human Nutrition - The effects of cocoa-derived polyphenols on cognitive functions have been analyzed through numerous studies using different interventions (doses, vehicles, time...  相似文献   
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