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An osteosarcoma of the femoral diaphysis associated with the presence of a bone plate in a dog  相似文献   

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Twenty fertilization experiments were set up in 1985 and 1986 in the Vosges mountains, using mostly calcareous or Mg fertilizers, in order to verify whether fertilization can attenuate defoliation and yellowing recently recorded in Silver fir and Norway spruce. In the Ardennes, a fertilization experiment set up in Norway spruce stands prior to the appearance of yellowing was assessed. In these areas, the total acid deposition is about 2 kg eq H+ ha−1 yr−1. Nitrogen deposition is much more important in the Ardennes (52 kg N ha−1 yr−1 in form of wet and dry deposition) than in the Vosges (16 kg N ha−1 yr−1). The results in the eight adult stands showed no uniform reaction to the treatments. Spontaneous improvement, further deterioration independently of the treatment, as well as a positive reaction to fertilization were observed. Additional N or P fertilization sometimes had a beneficial effect on Ca or Mg treatments. The selection of the stands with the best response turns out to be difficult, as the nutrient contents of needles alone seem not to be a satisfactory criterion for selection. Young plantations reacted positivley to the treatments. Soluble Mg fertilizer leads to an immediate response. Low solubility Ca-Mg fertilizers (Ca-Mg lime) did not produce reactions until three years after the application. In the Ardennes, in a 40 yr old spruce stand suffering from severe Mg deficiency, a Ca and Ca-phosphate fertilization applied 5 yr before yellowing appeared had positive effects on crown density, discoloration and wood production. Conversely, a single N fertilization in this experiment, as well as in a young plantation in the Vosges, had a marked negative effect on Mg nutrition, even at low levels.  相似文献   
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A new fipronil-based spot-on formulation was evaluated against experimental flea infestations in cats in two studies. In both studies, eight cats served as negative controls (groups 1 and 4); on day 0, eight cats were treated with a 10% w/v fipronil-based spot-on solution (Effipro Spot-on, 0.5ml per cat, groups 2 and 5) and eight cats served as positive controls (Frontline Spot-on, 0.5ml per cat, groups 3 and 6). Each cat was infested on day - 1 with 50 fleas (study 1) and weekly (day 7-day 56) with 100 fleas (study 2). Geometric mean flea counts obtained 48h after the treatment or each re-infestation were reduced by 99.0 and 98.3% in groups 2 and 3, respectively, on day 2, compared to the negative control group. Cats were protected from re-infestations with an efficacy >99% for 58 days in group 5 and for 37 days in group 6.  相似文献   
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A powder of quality elk velvet antler (QEVA) was evaluated on client-owned dogs with osteoarthrosis (OA) in a clinical, double-blind, and placebo-controlled study. Thirteen dogs received a placebo for 30 days and then QEVA for 60 days. Twenty-five other dogs received QEVA for 60 days. Gait analysis measured with a force plate, clinical signs assessed by an orthopedic surgeon, performances in daily life activities and vitality assessed by the owners, and complete blood analyses were obtained at days 0, after 30 days of placebo and/or 60 days of QEVA. On placebo, the 13 dogs did not show significant improvement (P < 0.05); however, their gait, their performances in daily life activities, and their vitality were significantly improved on QEVA, based on changes in values exceeding those observed when placebo was administered. The 25 dogs on QEVA for 60 days showed similar improvements. No clinical changes were revealed on blood analyses. Administration of QEVA was effective in alleviating the condition in arthritic dogs.  相似文献   
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Picosecond optical excitation was used to coherently control the excitation in a single quantum dot on a time scale that is short compared with the time scale for loss of quantum coherence. The excitonic wave function was manipulated by controlling the optical phase of the two-pulse sequence through timing and polarization. Wave function engineering techniques, developed in atomic and molecular systems, were used to monitor and control a nonstationary quantum mechanical state composed of a superposition of eigenstates. The results extend the concept of coherent control in semiconductors to the limit of a single quantum system in a zero-dimensional quantum dot.  相似文献   
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The spatially dependent de-excitation of a beam of metastable argon atoms, traveling through an optical standing wave, produced a periodic array of localized metastable atoms with position and momentum spreads approaching the limit stated by the Heisenberg uncertainty principle. Silicon and silicon dioxide substrates placed in the path of the atom beam were patterned by the metastable atoms. The de-excitation of metastable atoms upon collision with the surface promoted the deposition of a carbonaceous film from a vapor-phase hydrocarbon precursor. The resulting patterns were imaged both directly and after chemical etching. Thus, quantum-mechanical steady-state atom distributions can be used for sub-0.1-micrometer lithography.  相似文献   
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The effects of growth hormone-releasing factor (GHRF) injections to sows during late gestation were investigated in two experiments. In the first one, four treatments were applied to eight catheterized sows according to two 4 x 4 Latin squares: oral administration of 2 mg of pyridostigmine, a cholinesterase inhibitor, per kilogram of BW (PYR group); i.m. injection of 50 micrograms of GHRF/kg BW (GHRF group); a combination of the pyridostigmine and GHRF treatments (PYR+GHRF); or i.m. injection of glucose (control). Pyridostigmine slightly increased the plasma concentration of growth hormone (GH). Growth hormone responses to GHRF and PYR+GHRF treatments were similar, with significantly elevated GH concentrations from 5 to 240 min after GHRF injection. In the second experiment, 36 sows were allocated to two treatments at 102 d of gestation. Until farrowing, they were injected twice daily with 50 micrograms of GHRF/kg BW (GHRF group) or isotonic glucose (control). The DM, N, fat, and energy content of 24 pigs per group was determined at weaning at 22 d. Six pigs per litter had ad libitum access to feed until slaughter at 100 kg BW and their carcasses were evaluated. Treatment with GHRF increased pregnancy duration (114.8 vs 113.6 d, P less than .05), weight of pigs at 13 d (3.69 vs 3.54 kg, P less than .05) and at weaning (5.74 vs 5.48 kg, P less than .05), and improved pig survival (86 vs 71%, P less than .05). Lipid (on a DM basis) and energy contents of the pigs slaughtered at weaning were significantly higher in the GHRF group than in the control group (14.4 vs 12.5% and 2,178 vs 2,029 kcal/kg, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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