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Latent herpes simplex virus in spinal ganglia of mice   总被引:76,自引:0,他引:76  
Herpes simplex virus establishes a persistent, latent infection in spinal ganglia after mice have recovered from posterior paralysis. Infectious virus is replicated when these ganglia are explanted and maintained as organ cultures in vitro.  相似文献   
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Turkeys are extremely sensitive to aflatoxin B1 (AFB1) which causes decreased growth, immunosuppression and liver necrosis. The purpose of this study was to determine whether probiotic Lactobacillus, shown to be protective in animal and clinical studies, would likewise confer protection in turkeys, which were treated for 11 days with either AFB1 (AFB; 1 ppm in diet), probiotic (PB; 1 × 1011 CFU/ml; oral, daily), probiotic + AFB1 (PBAFB), or PBS control (CNTL). The AFB1 induced drop in body and liver weights were restored to normal in CNTL and PBAFB groups. Hepatotoxicity markers were not significantly reduced by probiotic treatment. Major histocompatibility complex (MHC) genes BG1 and BG4, which are differentially expressed in liver and spleens, were not significantly affected by treatments. These data indicate modest protection, but the relatively high dietary AFB1 treatment, and the extreme sensitivity of this species may reveal limits of probiotic-based protection strategies.  相似文献   
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From 2004 till 2008, Diplura were sampled at 96 localities in Belgium. Nine different species of Campodea were collected: Campodea fragilis Meinert 1865, Campodea lankesteri Silvestri 1912, Campodea lubbocki Silvestri 1912, Campodea meinerti Bagnall 1918, Campodea plusiochaeta Silvestri 1912, Campodea remyi Denis 1930, Campodea rhopalota Denis 1930, Campodea staphylinus Westwood 1842 and Campodea wallacei Bagnall 1918. The ordination technique non-metric multidimensional scaling indicated that pH and temperature/humidity were probably the most important variables determining species composition. However, it was remarkable that almost all combinations of species were encountered in the field, often even under the same stone. As no temporal segregations seem to take place, it remains unknown how these very similar species can occur together.  相似文献   
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A maintenance diet containing 44.4% dry weight protein and 2 reduced protein diets containing 17.2% and 8.2% dry weight protein were studied in dogs with induced chronic renal failure to determine effects on their (1) clinical status, (2) renal function, (3) electrolyte and acid-base balance, (4) divalent ion balance, (5) nutritional status, (6) hematologic status, and (7) hemostasis. A cross-over design of feeding was utilized so that the effect of diet could be studied in each dog at a known state of renal dysfunction and so that reversibility of effects could be determined. The inulin clearance rate was higher when the 44.4% protein diet was fed than when the 8.2% or 17.2% protein diets were fed. However, consumption of lower protein diets was associated with greater physical activity and reduction in serum urea nitrogen concentrations, compared with consumption of the 44.4% protein maintenance diet. Varying degrees of hyperchloremic metabolic acidosis developed in dogs fed the 8.2% and 17.2% protein diets. Reduced total serum protein and albumin concentrations, and hypercholesterolemia developed in dogs fed the 8.2% protein diet. All effects were reversible after diets were changed. It was concluded that diet-induced alterations in renal function associated with moderate dietary protein restriction did not adversely effect clinical and biochemical status of dogs with renal failure. It was unclear whether the clinical and biochemical changes observed with more severe protein restriction resulted from diet-induced changes in renal function.  相似文献   
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