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241.
This study analyzed the pharmacokinetics of orbifloxacin (OBFX) in plasma, and its migration and retention in epithelial lining fluid (ELF) and alveolar cells within the bronchoalveolar lavage fluid (BALF). Four healthy calves received a single dose of OBFX (5.0 mg/kg) intramuscularly. Post-administration OBFX dynamics were in accordance with a non-compartment model, including the absorption phase. The maximum concentration (Cmax) of plasma OBFX was 2.2 ± 0.1 μg/ml at 2.3 ± 0.5 hr post administration and gradually decreased to 0.3 ± 0.2 μg/ml at 24 hr following administration. The Cmax of ELF OBFX was 9.3 ± 0.4 μg/ml at 3.0 ± 2.0 hr post administration and gradually decreased to 1.2 ± 0.1 μg/ml at 24 hr following administration. The Cmax of alveolar cells OBFX was 9.3 ± 2.9 μg/ml at 4.0 hr post administration and gradually decreased to 1.1 ± 0.2 μg/ml at 24 hr following administration. The half-life of OBFX in plasma, ELF, and alveolar cells were 6.9 ± 2.2, 7.0 ± 0.6, and 7.8 ± 1.6 hr, respectively. The Cmax and the area under the concentration-time curve for 0–24 hr with OBFX were significantly higher in ELF and alveolar cells than in plasma (P<0.05). These results suggest that OBFX is distributed and retained at high concentrations in ELF and alveolar cells at 24 hr following administration. Hence, a single intramuscular dose of OBFX (5.0 mg/kg) may be an effective therapeutic agent against pneumonia.  相似文献   
242.
This study was intended to determine the modulatory effects of dietary supplementation of purple sweet potato ( Ipomoea batats Poir., PSP) on the immune response of chickens. PSP was included in a basal starter diet by 1% (PSPL) or 3% (PSPH) and continually fed. Newcastle disease (NDV) vaccine, Brucella abortus (BA) and sheep red blood cells (SRBC) were used for chicken immunization. Antibody titers against these antigens were used to estimate humoral immunity. Concanavalin A (Con A)-induced proliferations of splenocytes, thymocytes and peripheral blood lymphocytes (PBL), ratios of CD4- and CD8-single positive and CD4-CD8-double negative (DN) cells in splenocytes, were both used to indicate cellular immunity. Relative weights of spleen, thymus and bursa and white blood cell (WBC) counts were studied. PSPH increased anti-NDV ( P  < 0.05), anti-BA ( P  < 0.01) and anti-SRBC titers ( P  < 0.05) in response to secondary immunization, whereas PSPL increased titers of anti-BA ( P  < 0.05) and anti-SRBC ( P  < 0.01). Proliferations of splenocytes and thymocytes were augmented with PSPL ( P  < 0.05). PSPH-treated chickens had lower ( P  < 0.05) ratios of CD4-sigle positive lymphocytes. Proliferation of PBL, weights of lymphoid organs and WBC counts were not affected. These results suggest that dietary PSP supplementation could enhance the immune response after immunization in chickens.  相似文献   
243.
Skin lesions possibly caused by Papillomavirus infections in two four-toed hedgehogs are described. In case 1, there was a papillary mass on the right hind limb. Histologically, the mass was consistent with a viral papilloma. In the other case, multifocal papillary masses with erosions and ulcers were found throughout the body, mainly on the extremities. Histology showed continuative lesions composed of acanthosis, Bowenoid in situ carcinoma, and squamous cell carcinoma, with abrupt transitions between the lesions. In both cases, keratinocytes in the granular layer infrequently had features of koilocytes and intranuclear inclusion bodies, and immunohistochemical staining was positive for anti-human papillomavirus antibody. To the best of the authors’ knowledge, this is the first pathological documentation of possibly papillomavirus-associated skin lesions in four-toed hedgehogs.  相似文献   
244.
为确定细胞色素P450酶系在白腐菌Phlebia lindtneri降解有机氯类农药氯丹中的作用,在液体培养条件下,以胡椒基丁醚和1-氨基苯并三唑作为细胞色素P450的抑制剂,分析了不同浓度抑制剂对氯丹的降解、代谢产物的生成以及中间代谢物降解的影响。结果表明:与对照相比,高浓度(1.0 mmol/L)胡椒基丁醚或1-氨基苯并三唑处理15 d后氯丹的降解率均下降了约60%,且其代谢产物中除七氯和二氯代六氯的检出量显著增加外,其余环氧化及羟基化代谢产物均未检出;此外,添加高浓度的抑制剂可导致白腐菌降解中间代谢产物七氯及二氯代六氯的降解率下降90%以上,氧化氯丹的降解率下降70%以上,但不影响环氧七氯的降解。表明细胞色素P450可能是氯丹降解的主要酶系,其参与催化了氯丹的初始羟基化和水解、七氯和二氯代六氯的环氧化及氧化氯丹的水解等多个反应过程。  相似文献   
245.
246.
Authentic herbarium specimens of Gloeosporium carthami and G. chrysanthemi as well as live Colletotrichum strains from Carthamus tinctorius, Chrysanthemum coronarium var. spatiosum, and Calendula officinalis were judged to be conspecific based on morphological and molecular phylogenetic analyses. Representative strains from three asteraceous plants were demonstrated by inoculation tests to possess specific pathogenicity to the host plants. We propose a new combination, Colletotrichum carthami, for the anthracnose pathogen of the asteraceous plants, designating our specimen of G. carthami as its epitype. We characterize the species, which differs from the closely related Colletotrichum simmondsii in its pathogenicity and molecular characteristics.  相似文献   
247.
A fruit rot, similar to brown rot, occurred on extremely early ripening Satsumas in Saga Prefecture in the early autumn of 1999. A single species of Phytophthora was isolated from the affected fruit. After nonwounding inoculation of healthy fruits of Citrus spp. including Satsuma with the isolated fungus, the fungus was reisolated from fruit with symptoms similar to those in nature. On the basis of its morphology and molecular analysis of the rDNA-internal transcribed spacer regions, the pathogen was identified as P. palmivora. This is the first report of P. palmivora as a causal pathogen of citrus brown rot in Japan.  相似文献   
248.
Understanding how molecules can restructure the surfaces of heterogeneous catalysts under reaction conditions requires methods that can visualize atoms in real space and time. We applied a newly developed aberration-corrected environmental transmission electron microscopy to show that adsorbed carbon monoxide (CO) molecules caused the {100} facets of a gold nanoparticle to reconstruct during CO oxidation at room temperature. The CO molecules adsorbed at the on-top sites of gold atoms in the reconstructed surface, and the energetic favorability of this reconstructed structure was confirmed by ab initio calculations and image simulations. This atomic-scale visualizing method can be applied to help elucidate reaction mechanisms in heterogeneous catalysis.  相似文献   
249.
In vitro gas production (GP) method was used to investigate associative effects on ruminal digestion when grains (corn or barley) were supplemented to spring pasture and autumn pasture. Pasture (75%) was incubated with 25% corn or barley and gas production was monitored up to 96 h. After incubation, the residues were used to determine dry matter and organic matter digestibility (DMD and OMD). Gas production parameters were analyzed by applying a single exponential equation. Organic matter effective degradability (OMED) was determined from GP parameters and OMD. The positive associative effects on the rate of GP, DMD, OMD and OMED were observed when spring pasture was incubated with corn. However, similar effects were not observed in a barley mixture. However, for autumn pasture, both corn and barley mixtures showed positive associative effects on rate of GP, OMD and OMED. The results of this study indicated that supplementation of corn would be better than barley for spring pasture with high water‐soluble carbohydrate contents, whereas both grain supplementations were effective to obtain positive associative effects on the rate of GP and OMED for autumn pasture with high cell wall content.  相似文献   
250.
We previously described that supplementary garlic, onion and purple sweet potato (PSP) enhance humoral immune response in White Leghorn chickens. In the present in vitro study, we investigated the effects of garlic (GE), onion (OE) and PSP (PSPE) extracts on proliferation, interleukin (IL)‐2 and interferon (INF)‐γ gene expression of stimulated lymphocytes. The effects on microbicidal activity, reactive oxygen species (ROS) and nitric oxide (NO) productions of stimulated peritoneal macrophages were studied as well. The results showed that GE augmented Concanavalin A (ConA)‐induced splenocytes (4, 8 and 16 µg/mL) and thymocytes (2, 4 and 8 µg/mL) proliferations, and gene expression of IL‐2 (8 and 16 µg/mL) and INF‐γ (16 µg/mL). None of the examined extracts had mitogenic effect nor stimulated bursacytes response to phorbol 12‐myristate 13‐acetate (PMA). Macrophages exhibited superior microbicidal activity and ROS production with GE at 4 and 8 µg/mL and with OE at 25.6 µg/mL. None of the extracts showed stimulatory effects on NO production. The extracts showed concentration‐dependent inhibitory effects on all measured parameters at higher concentrations. Taken together, it is likely that garlic has direct stimulatory effects on immune cell functions, whereas the in vitro inhibitory effects of onion and PSP were likely attributed to high flavonoid contents.  相似文献   
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