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71.
72.
The clocklike properties of pulsars moving in the gravitational fields of their unseen neutron-star companions have allowed unique tests of general relativity and provided evidence for gravitational radiation. We report here the detection of the 2.8-second pulsar J0737-3039B as the companion to the 23-millisecond pulsar J0737-3039A in a highly relativistic double neutron star system, allowing unprecedented tests of fundamental gravitational physics. We observed a short eclipse of J0737-3039A by J0737-3039B and orbital modulation of the flux density and the pulse shape of J0737-3039B, probably because of the influence of J0737-3039A's energy flux on its magnetosphere. These effects will allow us to probe magneto-ionic properties of a pulsar magnetosphere.  相似文献   
73.
Trichophyton benhamiae was diagnosed in a 9-year-old female dog by histopathological evaluation, fungal culture and confirmation by sequencing of the internal transcribed spacer region of ribosomal DNA. Successful therapy was achieved with itraconazole, bathing with miconazole and chlorhexidine shampoo, and topical application of sodium hypochlorite as a rinse.  相似文献   
74.
The pharmacokinetics of dantrolene and its active metabolite, 5‐hydroxydantrolene, after a single oral dose of either 5 or 10 mg/kg of dantrolene was determined. The effects of exposure to dantrolene and 5‐hydroxydantrolene on activated whole‐blood gene expression of the cytokines interleukin‐2 (IL‐2) and interferon‐γ (IFN‐γ) were also investigated. When dantrolene was administered at a 5 mg/kg dose, peak plasma concentration (Cmax) was 0.43 μg/mL, terminal half‐life (t1/2) was 1.26 h, and area under the time–concentration curve (AUC) was 3.87 μg·h/mL. For the 10 mg/kg dose, Cmax was 0.65 μg/mL, t1/2 was 1.21 h, and AUC was 5.94 μg·h/mL. For all calculated parameters, however, there were large standard deviations and wide ranges noted between and within individual dogs: t1/2, for example, ranged from 0.43 to 6.93 h, Cmax ratios ranged from 1.05 to 3.39, and relative bioavailability (rF) values ranged from 0.02 to 1.56. While activated whole‐blood expression of IL‐2 and IFN‐γ as measured by qRT‐PCR was markedly suppressed following exposure to very high concentrations (30 and 50 μg/mL, respectively) of both dantrolene and 5‐hydroxydantrolene, biologically and therapeutically relevant suppression of cytokine expression did not occur at the much lower drug concentrations achieved with oral dantrolene dosing.  相似文献   
75.

Colombia is a country recognized for its variety of fresh flowers for export, among which roses represent a significant quantity. However, cut flowers must meet some quality requirements imposed by the international market. Ascorbic acid in living organisms has an extensive function as a free radical scavenger; therefore, it reduces the negative effects of oxidative stress. It is also involved in the biosynthesis of several hormones, has many functions in chloroplasts, and is a fundamental compound for the correct functioning of the photosynthetic apparatus. The exogenous application of ascorbic acid improves the quality and nutritional value of agricultural products and induces stress resistance in plants. A greenhouse study was carried out in Cota, Colombia, with the objective of improving the quality of rose flowers by spraying ascorbic acid in concentrations of 0.0 (control), 600, and 1200?mg?L?1 in the Escimo, Latin Beauty, and Freedom cultivars. In response to the spraying, an increase in stem length and stem thickness was observed in all cultivars which was directly proportional to the concentration of ascorbic acid applied. There was no clear trend found in the response of cultivars to ascorbate regarding head size and chlorophyll content (SPAD) since in some cultivars, the values of these variables increased or decreased with statistically significant differences. As a result, spraying with ascorbic acid significantly improves some components of the quality of rose cut flowers, even though the response is highly dependent on the cultivar.

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