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21.
Leptin and leptin receptors during malaria infection in mice   总被引:2,自引:0,他引:2  
Leptin, which is involved in a range of physiological processes, could be an important factor in the pathogenesis of malaria. We found that levels of leptin in serum and urine in Plasmodium berghei-infected mice increased progressively after infection, reaching a maximum value on day 6 post-infection. Serum values were approximately five-fold higher in infected mice than in non-infected controls. A similar relation was found for values of leptin in urine. Soluble leptin receptor levels also increased significantly in serum, more or less in line with the leptin increase. Our work represents the first report of visibly augmented leptin and soluble leptin receptor secretion in malarial infection.  相似文献   
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The objective of this study was to describe the arterial distribution of the hindfoot of the llama (Lama glama). Ten adult llamas, preserved in 6% formalin solution at 0 degree C, were dissected. The arterial system was perfused with a solution of 14% coloured plaster; the venous system was perfused with a solution of 17% coloured industrial gelatin. Angiographies were also obtained. In the llama, the arterial distribution is of the saphenous type and this simple sort of irrigation could be used as a didactic model. The caudal branch of the saphenous artery divides into the small lateral plantar artery and the larger medial plantar artery, which continues as the plantar common digital artery III, and it is the main blood supply of the hindfoot. The dorsal pedal artery is underdeveloped and the perforating tarsal artery does not exist in this species. The plantar common digital artery III divides into the plantar proper digital II, III and IV. Branches from the plantar proper digital artery III supply the digits. We compared the arterial distribution of the hindfoot of the llama with that of other domestic animals including the one-humped camel (Camelus dromedarius).  相似文献   
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Objective: To describe a case of abdominal compartment syndrome in a dog with babesiosis. Case summary: A 9‐year‐old female Bull Terrier presented with complicated babesiosis. Additional findings including respiratory distress, abdominal distension, and a decrease in urine output associated with an elevated abdominal pressure (23.5–25 cmH2O) led to a further diagnosis of abdominal compartment syndrome. This case report describes the clinical course of both conditions through resolution. New information provided: Abdominal compartment syndrome is not well described in the veterinary literature, but clinicians should be aware of this potential complication in critically ill patients. The pathophysiology and veterinary literature of abdominal compartment syndrome are reviewed.  相似文献   
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Veterinary Research Communications - The black-handed spider monkey (Ateles geoffroyi) is a platyrrhine primate distributed in southern Mexico, Central America, and part of South America. Two...  相似文献   
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Isolated cotyledons from mature Pinus pinea L. embryos were cultured in vitro in a factorial combination of 4.4, 10 and 44.4 microM N6-benzyladenine (BA) for 2, 4, 8, 16 and 35 days to optimize shoot regeneration. Incubation of explants in 44.4 microM BA for 4 days, in place of the standard incubation in 4.4 microM BA for 35 days, reduced the entire culture period to 4 weeks. Shortening the culture period had no significant effect on the caulogenic response or the number of buds formed per cotyledon. To establish the relationship between key moments in the caulogenic process induced by 4.4 microM BA and the endogenous concentrations of the active forms of BA and other isoprenoid-type cytokinins (CKs), we examined uptake, metabolism and amount of BA, as well as the amounts of zeatin, dihydrozeatin and their ribosides in P. pinea cotyledons after 1, 2, 6, 12 and 24 h, and 2, 4, 8, 16 and 35 days of exposure to 8-[14C]BA. Uptake and release of BA were associated with water movement between explants and the medium during the first 8 days of culture. The interconvertible forms of BA were the main metabolites formed in the tissues. Inactivation of BA as a result of conjugation or oxidation was insignificant. The endogenous concentration of BA + N6-benzyladenosine was 20-fold higher than the exogenously applied BA during the competence acquisition phase (Days 0-3). The concentration of isoprenoid-type CKs also increased 16-fold and then decreased during this time. Induction of shoot buds (Days 4-8) was characterized by a second peak of BA uptake by explants that triggered the synthesis of N6-benzyladenosine-5 -monophosphate and by the maintenance of isoprenoid-type CKs. Reestablishment of CK homeostasis marked the shift from the induction phase to the shoot development phase in this organogenic process (Days 8-12).  相似文献   
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Lameness is one of the most painful conditions that affects dairy cattle. This study was conducted to evaluate clinical signs and plasma concentration of several pain and stress biomarkers after oligofructose-induced lameness in dairy heifers. Lameness was induced using an oligofructose overload model in 12 non-pregnant heifers. Clinical parameters and blood samples were obtained at 48 and 24 h and at 6, 12, 24, 36 and 48 h after induction of lameness. Clinical parameters included heart rate, respiratory rate, ruminal frequency and lameness score. Plasma biomarkers included cortisol, haptoglobin, norepinephrine, beta-endorphin and substance P. Differences were observed in all parameters between control and treated heifers. The plasma concentration of biomarkers increased significantly in treated animals starting 6 h after induction of lameness, reaching maximum levels at 24 h for cortisol, 48 h for haptoglobin, 6 h for norepinephrine, 12 h for substance P and at 24 h for beta-endorphin. Overall, our results confirm that lameness associated pain induced using the oligofructose model induced changes in clinical parameters and plasma biomarkers of pain and stress in dairy heifers.  相似文献   
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Bats are hosts of diverse coronaviruses (CoVs) known to potentially cross the host–species barrier. For analysing coronavirus diversity in a bat species‐rich country, a total of 421 anal swabs/faecal samples from Costa Rican bats were screened for CoV RNA‐dependent RNA polymerase (RdRp) gene sequences by a pancoronavirus PCR. Six families, 24 genera and 41 species of bats were analysed. The detection rate for CoV was 1%. Individuals (n = 4) from four different species of frugivorous (Artibeus jamaicensis, Carollia perspicillata and Carollia castanea) and nectivorous (Glossophaga soricina) bats were positive for coronavirus‐derived nucleic acids. Analysis of 440 nt. RdRp sequences allocated all Costa Rican bat CoVs to the α‐CoV group. Several CoVs sequences clustered near previously described CoVs from the same species of bat, but were phylogenetically distant from the human CoV sequences identified to date, suggesting no recent spillover events. The Glossophaga soricina CoV sequence is sufficiently dissimilar (26% homology to the closest known bat CoVs) to represent a unique coronavirus not clustering near other CoVs found in the same bat species so far, implying an even higher CoV diversity than previously suspected.  相似文献   
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