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Rongbo Wang Shuzhun Chen Bowen Zheng Peiqing Liu Benjin Li Qiyong Weng Qinghe Chen 《Forest Pathology》2019,49(5)
Taxus chinensis is a valuable tree with uses for timber, medicinal, ornamental and landscape purposes. Most importantly, it is a source of the anti‐cancer drug paclitaxel. In 2016, needle spot disease was observed on T. chinensis in Fujian Province of China. Five isolates of similar morphology were isolated from diseased samples. The pathogen was identified as Neopestalotiopsis clavispora based on morphological and cultural characteristics and confirmed by sequence analysis of the internal transcribed spacer region (ITS) and the large subunit ribosomal RNA gene (LSU). The pathogenicity of the isolates was confirmed by fulfilling Koch's postulates. To the best of our knowledge, this is the first report to indicate that the causal agent of needle spot disease on Chinese yew in China is N. clavispora. 相似文献
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Sedqyar M Weng Q Watanabe G Kandiel MM Takahashi S Suzuki AK Taneda S Taya K 《The Journal of reproduction and development》2008,54(2):100-106
The objective of this study was to investigate the changes in secretion of inhibin and cellular localization of the inhibin alpha and inhibin/activin (beta(A) and beta(B)) subunits in male Japanese quail from 1 to 7 weeks after hatching. The post-hatch profile of plasma luteinizing hormone (LH), immunoreactive (ir) inhibin and testosterone were measured by radioimmunoassay. Testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against inhibin alpha, inhibin/activin beta(A) and inhibin/activin beta(B) from one week of age to sexual maturity. Testicular weight increased gradually until 4 weeks and abruptly increased from 5 weeks of age onwards. The plasma concentrations of LH and ir-inhibin increased significantly at 5 weeks of age, and the plasma concentration of testosterone increased significantly at 6 weeks of age. Pituitary contents of LH showed a steady increase until 6 weeks of age and then abruptly increased at 7 weeks of age. Coincident to the increase in plasma testosterone, the testicular contents of testosterone significantly increased from 5 weeks through sexual maturity. Immunohistochemically, localization of the inhibin/activin alpha, beta(A) and beta(B) subunits was found in the Sertoli and Leydig cells at all ages of development from one week of age to sexual maturity. These results suggest that Sertoli and Leydig cells are the major source of inhibin secretion during development in male Japanese quail. 相似文献
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Weng Q Shi Z Kawaguchi M Watanabe G Taya K 《The Journal of reproduction and development》2008,54(5):397-401
Characteristic daily increases in the plasma levels of luteinizing hormone (LH) are present every afternoon during lactation in golden hamsters. The objective of this study was to investigate the effect of the diurnal rhythm of increases in LH on expression of nerve growth factor (NGF), its receptors trkA and p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters. Both lactating and non-lactating groups of postpartum golden hamsters were used in this study. The expression of NGF, its receptors trkA and p75 and inhibin alpha-subunit were determined by immunohistochemistry. Positive staining of NGF, trkA and p75 was found in the interstitial cells of the lactating group, and no immunoreactivity for NGF, trkA or p75 was observed in the ovarian interstitial cells of the non-lactating group. In addition, immunostaining of inhibin alpha-subunit was also observed in the interstitial cells of the lactating group but not in those of the non-lactating group. Immunostaining of the inhibin/activin beta(A)- and beta(B)-subunits was observed in the granulosa cells of antral follicles, but not in the interstitial cells of the lactating and non-lactating animals. These results suggest that the diurnal rhythm increases in LH can induce expression of NGF, trkA, p75 and inhibin alpha-subunit in the ovarian interstitial cells of lactating golden hamsters and that NGF, its receptors trkA and p75 and inhibin alpha-subunit may have the capacity for autocrine or paracrine modulation of interstitial cell differentiation in golden hamsters. 相似文献
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Lee DN Chuang YS Chiou HY Wu FY Yen HT Weng CF 《Journal of animal physiology and animal nutrition》2008,92(4):463-470
This study attempted to determine ingested porcine epidermal growth factor (pEGF) on the gastrointestinal tract development of early-weaned piglets. Thirty-two piglets (14-day weaned) were randomly allotted to supplemented with 0 (control), 0.5, 1.0, or 1.5 mg pEGF/kg diet. Each treatment consisted of four replicates with two pigs per pen for a 14 days experimental period. Piglets were sacrificed and gastrointestinal tract samples were collected to measure mucosa morphology, mRNA expression and activities of digestive enzymes in the gastrointestinal tract of piglets at the end of the experiment. Diets supplemented with pEGF failed to influence growth performance but tended to increase jejunal mucosa weight (p < 0.09) and protein content (p < 0.07). Piglets supplemental pEGF induced incrementally the gastric pepsin activity (p < 0.05) and stimulated jejunal alkaline phosphatase (ALP) and lactase activities accompanied with the increase of jejunal ALP and maltase mRNA expression. No effect of pEGF on the activities of all enzymes in ileum except the stimulation of ileal aminopeptide N mRNA expression. These results reveal that dietary pEGF supplementation might enhance gene expression and activities of digestive enzymes in the stomach and jejunum of piglets. 相似文献
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表面活性剂APSA-80对井冈霉素的增效作用研究 总被引:2,自引:0,他引:2
在750倍的井冈霉素药液中加入0.01%、0.02%和0.04%浓度的表面活性剂APSA-80后,其表面张力降低了32.87%~53.66%、药液液滴在水稻的叶表面和叶背面的接触角分别降低了25.26%~51.98%和36.88%~47.34%,在叶鞘上降低22.38%~37.18%;药液在叶片上的沉积量提高约1.6倍;盆栽试验结果表明,APSA-80能够提高井冈霉素药液抗雨水冲刷能力;田间药效试验结果显示,APSA-80能够提高井冈霉素防治纹枯病的效果和延长其持效期。药后14 d,加入0.02%和0.04% APSA-80的处理防效明显高于单用;药后21 d,加入0.04%的,防效仍保持86.58%(96年)和90.93%(97年),极明显高于单用。 相似文献
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研究腐蚀和磨损交互作用的试验装置 总被引:1,自引:0,他引:1
设计和试验和旋转试片式摩擦电化学试验装置。该装置用来研究腐蚀和磨损过程的交互作用。并用称重法和电化学方法确定腐蚀和磨损过程中材料总损失重、纯腐蚀量、纯磨损量和交互作用量。交互作用的两个分量为腐蚀增量和在损增量,这两个分量 同样可以从测量中得到。这些数据为研究腐蚀和磨损过程材料损失模型提供也研究基础。 相似文献