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341.
A seven-year-old castrated male Yorkshire terrier dog was presented for a recurrent skin disease. Erythematous skin during the first visit progressed from multiple plaques to patch lesions and exudative erosion in the oral mucosa membrane. Biopsy samples were taken from erythematous skin and were diagnosed with epitheliotropic T cell cutaneous lymphoma by histopathology and immunochemical stain. In serum chemistry, the dog had a hypercalcemia (15.7 mg/dl) and mild increased alkaline phosphatase (417 U/l). Immunohistochemistry was performed to detect parathyroid hormone-related peptide (PTH-rP) in epitheliotropic cutaneous lymphoma tissues but the neoplastic cells were not labeled with anti-PTH-rP antibodies. The patient was treated with prednisolone and isotretinoin. However, the dog died unexpectedly.  相似文献   
342.
选取塔里木南缘克里雅河流域绿洲为研究靶区,利用Landsat-ETM+卫星图像数据和野外调查数据分析盐渍化土壤与地表反照率(Albedo)、土壤盐分指数(SI)之间的关系。回归分析发现,盐渍化土壤在SI-Albedo特征空间分布具有显著规律,即非盐渍化土壤呈团状分布;轻、中度盐渍化土壤具有线性分布特征;非盐渍化土壤与轻度盐渍化土壤分异明显。结合分异规律,编制分类算法模型,得到研究区盐渍化土壤信息提取结果,并与传统监督最大似然分类法结果进行对比分析。结果表明,在SI-Albedo特征空间中定量快速提取盐渍化土壤信息的总体效果较好,对准确且自动提取干旱区盐渍化土壤信息以及区域尺度盐渍化遥感监测研究具有重要意义。  相似文献   
343.
挥发性碳氢化合物是含脂食品辐照鉴定的标识性化合物,采用两种不同的前处理方法即SPE(固相萃取)和SPME(固相微萃取),对葵花籽辐照前后的6种碳氢化合物即1-C14:1(1-十四烯)、C15:0(正十五烷)、1-C16:1(1-十六烯)、C17:0(正十七烷)、1,7-C16:2(1,7-十六二烯)和8-C17:1(8-十七烯)进行了GC-MS(气相色谱质谱)分析,建立了能判别葵花籽是否经过辐照的鉴定方法,同时还研究了不同辐照剂量和炒制加工处理对葵花籽中6种碳氢化合物的影响。研究结果表明,SPE-GC-MS法和HS-SPME-GC-MS法均能用于葵花籽的辐照鉴定,其中HS-SPME-GC-MS法操作简便,能对葵花籽中的碳氢化合物进行准确快速的定性分析。未辐照葵花籽中检出了4种碳氢化合物,分别是1-C14:1、C15:0、1-C16:1、C17:0,而1,7-C16:2和8-C17:1仅在葵花籽辐照后产生,是进行辐照鉴定的最佳标识物。剂量对碳氢化合物的变化影响明显,随着辐照剂量的增加,1,7-C16:2和8-C17:1的水平显著提高,为辐照葵花籽的定量检测提供了理论依据。  相似文献   
344.
Effect of the pendant n-butyl group on shape recovery and tensile properties of polyurethane (PU) block copolymer was investigated. The grafted n-butyl group was intended to keep PU chains away and to deter molecular interaction between PU chains by its flexible chains, and thus improve shape recovery at subzero temperature while maintaining high and reproducible tensile properties and shape recovery at ambient temperature. The attachment of n-butyl group did not make any change in the molecular interaction and phase separation of hard and soft segments in PU structure as judged from IR and DSC analysis. Cross-link density and intrinsic viscosity increased with the increase of n-butyl content due to the partial cross-linking by the linking reagent. Shape recovery and shape retention were not diminished after cyclic shape memory tests. Finally, the effect of n-butyl group on low temperature shape recovery was compared with linear ones and the potential application of this finding was discussed.  相似文献   
345.
For innate immune defense, lower animals such as fish and amphibian are covered with skin mucus, which acts as both a mechanical and biochemical barrier. Although several mucus sources have been isolated and studied for their biochemical and immunological functions, the precise mechanism(s) of action remains unknown. In the present study, we additionally found the eel skin mucus (ESM) to be a promising candidate for use in anti-tumor therapy. Our results showed that the viability of K562 cells was decreased in a dose-dependent manner by treatment with the isolated ESM. The cleaved forms of caspase-9, caspase-3 and poly adenosine diphosphate-ribose polymerase were increased by ESM. The levels of Bax expression and released cytochrome C were also increased after treatment with ESM. Furthermore, during the ESM mediated-apoptosis, phosphorylation levels of ERK1/2 and p38 but not JNK were increased and cell viabilities of the co-treated cells with ESM and inhibitors of ERK 1/2 or p38 were also increased. In addition, treatment with lactose rescued the ESM-mediated decrease in cell viability, indicating lactose-containing glycans in the leukemia cells acted as a counterpart of the ESM for interaction. Taken together, these results suggest that ESM could induce mitochondria-mediated apoptosis through membrane interaction of the K562 human leukemia cells. To the best of our knowledge, this is the first observation that ESM has anti-tumor activity in human cells.  相似文献   
346.
This study explored the pathways of ingress of Acidovorax citrulli, the causal agent of bacterial fruit blotch of cucurbits, into watermelon seeds. Up until 7 days post‐inoculation (DPI), a significantly higher percentage of watermelon seeds was infected with A. citrulli when the bacteria were applied (c. 1 × 106 colony‐forming units) to stigmas versus ovary pericarps of female flowers. Immunofluorescence microscopy showed that, with stigma inoculation, A. citrulli colonized style and ovary tissues by 1 DPI, and the bacteria co‐localized with pollen germ tubes in these tissues. With ovary pericarp inoculation, A. citrulli cells penetrated the epicarp and mesocarp tissues by 1 DPI but did not reach endocarp until 4 DPI. Finally, manual pollination followed by stigma inoculation led to >53% A. citrulli‐infected seed lots, while A. citrulli was not detected in seeds/ovules generated by stigma inoculation without pollination (chemically induced parthenocarpy). These results show that stigma inoculation results in faster colonization of watermelon ovules by A. citrulli than pericarp inoculation, even though there is no difference in the levels of infection in mature seeds. The data also indicate that pollen germ tubes play an important role in A. citrulli ingress into watermelon seeds via stigmas.  相似文献   
347.
银川阅海公园水生植物园规划   总被引:1,自引:0,他引:1  
银川阅海湿地公园是国家级湿地公园,对银川阅海公园水生植物园的规划建设,可以完善阅海湿地公园的整体布局、功能及生态系统,促进银川阅海公园生态与经济的和谐发展。同时本项目的规划建设对提高银川地区水生植物资源的开发利用、保护生物多样性、扩大银川阅海公园的知名度将产生积极而深远的影响。  相似文献   
348.
本试验采用嫩枝扦插法繁殖园林观赏植物,以不同基质和植物生长调节剂ABT生根粉、1-NAA、吲哚-3-丁酸,其中ω(1-NAA):ω(吲哚-3-丁酸)=1∶1为混合处理试剂.混合处理试剂,以不同质量分数配成的溶液处理插穗,通过分析扦插基质对插穗生根的影响以及不同植物生长调节剂的不同质量分数对插穗生根的影响,结果表明:1-NAA和吲哚-3-丁酸的混合试剂以100倍质量分数处理的金叶小檗插穗在蛭石中扦插长势最好;经ABT生根粉处理的插穗在蛭石中扦插以1/7 000的质量分数处理较好;经1-NAA处理的插穗在蛭石中以250倍质量分数处理较好;经吲哚-3-丁酸各质量分数处理的插穗在蛭石中扦插均表现不理想.为此总结出不同植物快速有效的扦插技术,采用此技术推广繁育上述植物,可增加银川地区园林绿化植物种类,提升园林绿化景观,改善城市生态环境.  相似文献   
349.
Sildenafil increases the cyclic guanosine monophosphate (cGMP) by inhibition of a phosphodiesterase 5, thereby leading to an antinociceptive effect. The increased cGMP may exert the effect on an L-type calcium channel through the activation of protein kinase G (PKG). The purpose of this study was to examine the possible involvement of a PKG-L-type calcium channel on the effect of sildenafil at the spinal level. Catheters were inserted into the intrathecal space of male SD rats. Pain was induced by applying 50 µL of a 5% formalin solution to the hindpaw. The sildenafil-induced effect was examined after an intrathecal pretreatment of a PKG inhibitor (KT 5823), or a L-type calcium channel activator (FPL 64176). Intrathecal sildenafil produced an antinociceptive effect during phase 1 (0~10 min interval) and phase 2 (10~60 min interval) in the formalin test. Intrathecal KT 5823 and FPL 64176 attenuated the antinociceptive effect of sildenafil during both phases. Sildenafil is effective against both acute pain and the facilitated pain state at the spinal level. In addition, the inhibition of an L-type calcium channel by activation of the PKG may contribute to the antinocieptive mechanism of sildenafil in the spinal cord.  相似文献   
350.
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