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171.
Developmental changes in the immune‐related cells of the gut during the first 2 weeks post hatching were determined in broiler chickens fed a corn–soybean meal (CS) based diet, a semi‐purified diet with high fat (HF) and a high carbohydrate (HC) diet. The expression of CD3 and interferon‐gamma (IFN‐γ) mRNA increased during 3–7 days of age. When the chicks were fed the CS diet, the expression of interleukin‐2 mRNA in the foregut did not increase with age. The expression of iNOS mRNA was lowered at 3 days of age in the fore‐ and mid gut but the expression was constant at the other days of age. TLR‐2 mRNA expression increased in three section of the gut during 3–7 days of age, while TLR‐4 expression increased during 0–3 days of age. Chicks fed the HC diet showed higher interleukin‐2 but lower IFN‐γ mRNA expression than birds fed the CS diet. Feeding the HF diet tended to decrease the expressions determined. These findings suggest that the functional maturation of the T cell does not always correlate with an increase in T cell numbers, maturation of innate immunity may occur earlier than that of T cells and possibly the dietary composition modifies the developmental pattern. 相似文献
172.
Tanaka R Soda A Saida Y Sugihara K Takashima K Shibazaki A Yamane Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(8):857-859
We performed a retrospective study of 56 dogs with Patent Ductus Arteriosus (PDA) to evaluate the indications for and efficacy of transarterial PDA coil embolization. Transarterial PDA coil embolization was conducted in 37 cases (66.1%) and surgical ligation was conducted in 16 cases (28.6%). Three cases (5.4%) were diagnosed as pulmonary hypertension and were excluded from surgical intervention. Although coil dislodgement was observed in the pulmonary artery in one case, no death occurred during coil embolization or surgical ligation. Echocardiography showed that fractional shortening decreased from 35.4 +/- 6.8% to 30.2 +/- 5.9% (P<0.05) after transarterial PDA coil embolization. Although slight residual shunts were observed in 18 cases, transarterial PDA coil embolization was effective treatment of PDA. 相似文献
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Kazuaki Uno Takahiko Aoki Walai Kleechaya Lila Ruangpan & Varin Tanasomwang 《Aquaculture Research》2006,37(8):826-833
This study examined the pharmacokinetics and bioavailability of oxolinic acid (OA) in black tiger shrimp Penaeus monodon Fabricius, in brackish water (salinity 10 g L?1) at 28–29°C, after intra‐sinus (10 mg kg?1) and oral (50 mg kg?1) administration and also investigated the net changes of OA residues in the shrimp after cooking (boiling, baking and frying). The haemolymph concentrations of OA after intra‐sinus dosing were best described by a two‐compartment open model. The distribution and elimination half‐lives were 0.84 and 17.7 h respectively. The apparent volume of distribution at a steady state and the total body clearance were estimated to be 2061 mL kg?1 and 90.1 mL kg?1 h?1 respectively. The bioavailability of OA after an oral administration was 7.9%. The peak haemolymph concentration, the time to peak haemolymph concentration and the elimination half‐life after oral administration were 4.20 μg mL?1, 4 h and 19.8 h respectively. Oxolinic acid muscle and shell levels increased to a maximum (muscle 1.76 μg g?1 and shell 8.17 μg g?1) at 4 h post administration and then decreased with the elimination half‐life value of 20.2 and 21.9 h respectively. Residual OA in muscle and shell was reduced by 20–30% by each cooking procedure examined. 相似文献
176.
The external hypha of arbuscular mycorrhizal (AM) fungi, extending from roots out into soil, is an important structure in the uptake of phosphate from the depletion zone around each root. In this paper, we analysed some phospholipid fatty acids (PLFAs) derived from external hyphae of four AM fungi (Glomus etunicatum, Glomus clarum, Gigaspora margarita and Gigaspora rosea) to find fatty acids which may be useful as specific markers for identifying and quantify the external hyphae of Gigaspora species. Leek (Allium porrum L.) seedlings inoculated with each AM fungus were grown in river sand. Sand samples were collected and four PLFAs (16:1ω5, 18:1ω9, 20:1ω9 and 20:4) in the sand were analysed. In addition, the hyphal biomass in the sand was determined by the direct microscopic method. PLFAs 18:1ω9 and 20:4 were found in all the AM-inoculated and non-inoculated sand samples. PLFA 16:1ω5 was detected in the sand inoculated with G. etunicatum, G. clarum and Gi. rosea. PLFA 20:1ω9 was detected only in the sand inoculated with Gi. rosea. PLFAs 16:1ω5 and 20:1ω9 were not found in the sand inoculated with Gi. margarita. The amount of PLFA 20:1ω9 was closely correlated with the amount of biomass of external hyphae of Gi. rosea (r=0.937, P<0.001), whereas no correlation was observed for PLFA 16:1ω5. The 20:1ω9 content of Gi. rosea was approximately 6.56 nmol mg−1 hyphal biomass. We suggest that PLFA 20:1ω9 can be used as a specific marker for identifying and quantifying the external hyphae of Gi. rosea, at least in controlled experimental systems. 相似文献
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Hata K Futaba DN Mizuno K Namai T Yumura M Iijima S 《Science (New York, N.Y.)》2004,306(5700):1362-1364
We demonstrate the efficient chemical vapor deposition synthesis of single-walled carbon nanotubes where the activity and lifetime of the catalysts are enhanced by water. Water-stimulated enhanced catalytic activity results in massive growth of superdense and vertically aligned nanotube forests with heights up to 2.5 millimeters that can be easily separated from the catalysts, providing nanotube material with carbon purity above 99.98%. Moreover, patterned, highly organized intrinsic nanotube structures were successfully fabricated. The water-assisted synthesis method addresses many critical problems that currently plague carbon nanotube synthesis. 相似文献
179.
Honglikith Daoluang Harada Masayoshi Hiramatsu Kazuaki Tabata Toshinori Ozaki Akinori 《Paddy and Water Environment》2022,20(1):153-175
Paddy and Water Environment - This study focuses on a method for improving water quality via anoxification recovery using underwater LED treatment in an organically polluted reservoir. The main aim... 相似文献
180.
Kazuaki Hiramatsu Yuji Oshima Suguru Inoue Shiomi Shikasho 《Paddy and Water Environment》2005,3(2):79-92
The environmental behavior and fate of tributyltin (TBT) in the northern Ariake Sea, resulting from the use of TBT-containing
antifouling paints on hulls of ships, pleasure crafts and docking facilities, was assessed by numerical simulations. First,
a mathematical model was devised on the basis of a non-steady state equilibrium, one box multi-compartment model consisting
of the surface micro-layer, the water column, the mud-layer, and the bottom sediment compartments. The movement of TBT among
the four compartments was modeled by resuspension of bottom mud, deposition of suspended sediment, film penetration and water
advection in each compartment. Furthermore, a one-dimensional diffusion equation was introduced into the bottom sediment compartment
to calculate profile distribution of TBT. The reactivity of TBT considered within the compartments included biological degradation,
adsorption to particulate matter and diffusion. Next, the optimal amount of past TBT loads, reflecting the recent observations
of TBT concentration in the waters and sediments of the northern Ariake Sea, was searched by a simple genetic algorithm. The
relative sensitivity of various model parameters were also determined to identify the more important parameters for estimating
the environmental behavior and fate of TBT. Finally, the future status of TBT contamination of the northern Ariake Sea was
predicted assuming the discontinued use of TBT-containing antifouling paints. Despite its simple model structure relative
to hydraulics, it was concluded that this multi-compartment model adequately estimated the environmental behavior and fate
of TBT. 相似文献