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Vitamin A-induced synthesis of alkaline phosphatase 总被引:1,自引:0,他引:1
Incorporation of radioactive leucine into electrophoretically separated proteins from mouse tail epidermis indicates that synthesis of alkaline phosphatase is stimulated by vitamin A. It is suggested that some of the diverse effects of vitamin A may be the result of alkaline phosphatase induction. 相似文献
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Behnke E Collar JI Cooper PS Crum K Crisler M Hu M Levine I Nakazawa D Nguyen H Odom B Ramberg E Rasmussen J Riley N Sonnenschein A Szydagis M Tschirhart R 《Science (New York, N.Y.)》2008,319(5865):933-936
Bubble chambers were the dominant technology used for particle detection in accelerator experiments for several decades, eventually falling into disuse with the advent of other techniques. We report here on a new application for these devices. We operated an ultraclean, room-temperature bubble chamber containing 1.5 kilograms of superheated CF3I, a target maximally sensitive to spin-dependent and -independent weakly interacting massive particle (WIMP) couplings. An extreme intrinsic insensitivity to the backgrounds that commonly limit direct searches for dark matter was measured in this device under operating conditions leading to the detection of low-energy nuclear recoils like those expected from WIMPs. Improved limits on the spin-dependent WIMP-proton scattering cross section were extracted during our experiments, excluding this type of coupling as a possible explanation for a recent claim of particle dark-matter detection. 相似文献
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Barnett JE Davison NJ Thornton SM Riley P Cooper T Wessels ME 《Journal of zoo and wildlife medicine》2011,42(2):338-341
A 4-yr-old male captive hooded seal (Cystophora cristata), previously diagnosed as hypothyroid, died after a 3-wk period of lethargy and inappetance despite treatment that included intramuscular administration of antibiotics and multivitamins. Gross pathologic findings included extensive muscle necrosis over the left flank, an underlying necrotic iliac lymph node, two necrotic pulmonary masses and a necrotic bronchial lymph node. Routine cultures yielded a number of bacterial isolates and a heavy pure fungal growth from the necrotic iliac lymph node; wet preparations of which revealed sporangiophores typical of Mucor sp. Histopathology of necrotic muscle, pulmonary lesions and bronchial and iliac lymph nodes revealed necrosis with a marked pyogranulomatous and eosinophilic inflammatory cell infiltrate and fungal hyphae consistent with a Zygomycete species. This is believed to be the first report of systemic mucormycosis in a pinniped likely to have originated from an injection site reaction. 相似文献
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The draft force, vertical up force and wear rate of 5-mm-thick pressed steel shares were compared with those of 10-mm-thick cast steel shares. The tests were conducted using a range of soil types and moisture contents over several years. Because they were made of a harder material, the cast shares lost mass at 0.48 of the rate of the pressed shares, irrespective of the soil type or condition. However, the cast shares, because they were made from thicker material, had a blunter cutting edge which in moist soil conditions increased the draft and vertical up forces.
The results showed the wear rate (based on distance) to be independent of the speed of tillage but the soil type and condition had a large effect on the wear rates and tillage forces. 相似文献
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SUMMARY To determine whether oral cobalt supplements could modify the clinical onset of annual ryegrass toxicity, groups (n = 5) of sheep were dosed orally with 0, 4 or 16 mg cobalt/day. After 3 weeks on this treatment, toxic ryegrass seed was added to their feed to provide 0, 0.15 and 0.30 mg corynetoxins/kg body weight, daily. Sheep receiving cobalt ingested 30% more toxin than did unsupplemented sheep before clinical signs developed (P = 0.03). There was no significant difference between groups receiving 4 and 16 mg cobalt. The results showed that cobalt delayed, but did not prevent, the onset of clinical signs of annual ryegrass toxicity. 相似文献
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