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81.
82.
经2002~2003年盆栽试验观察,粗皮病的发生与土壤高锰含量有直接关系.施锰300mg/kg以下树体生长发育正常,施锰350 mg/kg前期上部枝少部分幼叶出现失绿现象,施锰400mg/kg以上树体发生粗皮病.施锰400mg/kg叶片锰最高值为890 mg/kg,是施锰350 mg/kg的3.1倍,土壤有效锰、易还原锰、交换锰含量最高值分别是施锰350 mg/kg的1.1、2.3、22.0倍.说明土壤高量的易还原锰、代换锰是粗皮病发生的重要因素.施锰发病后土壤铁、硅的含量降低,磷、钾的含量提高. 相似文献
83.
在晾晒24h的苜蓿草渣中分别加入0、10、20g/kg的丙酸进行青贮。结果表明,添加丙酸能明显降低青贮料的pH值以及氨态氮、丁酸的含量和保存更多的蛋白质。在本次试验中,以20g/kg丙酸添加组的青贮效果最好。 相似文献
84.
There is little available information on the effects of temperature and CO2 enrichment on stomata anatomical characteristics of plants. Effect of these two microclimates was studied on five rose (Rosa spp.) cultivars, viz. ‘First Red’ (used as check), ‘Arjun’, ‘Raktima’, ‘Raktagandha’ and ‘Pusa Pitamber’. Budded, single-stemmed rose cultivars having five lateral buds were grown in controlled environment growth cabinets under enriched CO2 (1000 μmol mol−1) and optimum (28/18 °C, T0) or high (35/25 °C, T1) temperature for 50 days. All observations were made on the abaxial leaf surface. Significant increases in stomatal density (68.7%), index (29.6%) and epidermal cell density (37.3%) were recorded in plants grown at high temperature over control with CO2 enrichment. The cultivars responded differently in terms of length and width of guard cell and stoma (pore) under high temperature, however, the values averaged over treatments showed a significant reduction in these parameters. Further, number of stomata per leaf was higher (28.3%) in plants grown at high temperature, except First Red. A reduction in mean leaf area (26.7%) and dry mass (32.0%) was recorded at high rather than optimum temperature. The specific leaf area was maximum in Arjun (87%) while in First Red, a 14% reduction was noted at high temperature. 相似文献
85.
AIM:To study the variety of cytokines in severe bacterial pneumonia of Sprague Dawleg (SD) rats. METHODS:A total of 60 SD rats were randomly divided into three groups: model Ⅰ group (n=24), model Ⅱ group (n=24), and control group (n=12). Rats in the model Ⅰ group and the model Ⅱ group were intratracheally instilled with suspension of klebsiella pneumoniae at different doses. Rats in the control group were intratracheally injected with 1 mL saline. On the 2nd, 4th and 6th day after intratracheal instillation, 1/3 rats in each group were killed to determine the concentration of IFN-γ, IL-6 and TNF-α in blood. RESULTS:The levels of IL-6 and TNF-α in model groups were higher than those in control group, while the level of IFN-γ was lower. The change of cytokines was more significant in the model Ⅱ group (severe pneumonia) than those in the model Ⅰ group. CONCLUSION:The cytokines we studied may play an important role in the pathogenesis of severe pneumonia. The change of cytokines is more significant in severe pneumonia than those in common pneumonia. 相似文献
86.
AIM: To establish the influenza infected mouse model and study the anti-inflammatory effect of ganmao shuangjie heji. METHODS: IV FM1 infected mice were used as the animal model. The changes of pathology and the cytokine TNF-α, IFN-γ and IL-10 in the lung were observed by HE staining and ELISA (double antibody sandwich enzyme linked immunosorbent assay) after ganmao shuangjie heji treatment. RESULTS: After infected by influenza virus, severe interstitial pneumonia was induced in the model group. Mild interstitial pneumonia was observed in ganmao shuangjie heji treated group. The protein expressions of cytokine TNF-α, IFN-γ and IL-10 were higher in model group than those in the control group. The protein expressions of TNF-α and IFN-γ in ganmao shuangjie heji treated group decreased and IL-10 expression increased significantly compared with model group. CONCLUSION: Ganmao shuangjie heji decreases the expressions of TNF-α and IFN-γ, and increases the expression of IL-10, thus, alleviates inflammatory injury. The clinical application of this medicine can shorten the course of disease. 相似文献
87.
88.
AIM: To investigate the activation of nuclear factor κB (NF-κB) induced by lipopolysaccharides (LPS) in rat alveolar macrophages (AMs) and its regulatory role in tumor necrosis factor (TNF-α) secretion. METHODS: The dynamic activity changes of NF-κB induced by LPS were determined with electrophoretic mobility shift assay (EMSA). Antisense oligonucleotides of NF-κB subunit (p65) were transfected into AMs prior to LPS stimulation. The effect of antisense oligonucleotide transfection on expressions of p65 and TNF-α in supernatant were measured with Western blotting and enzyme linked immunosorbent assay (ELISA), respectively.RESULTS: NF-κB activity increased markedly and reached its peak level at 4 h after LPS stimulation. After transfected with antisense oligonucleotides of NF-κB subunit (p65), expression of p65 and TNF-α in supernatant decreased markedly.CONCLUSION: NF-κB activity has a positive effect on regulating secretion of TNF-α in AMs induced by LPS. 相似文献
89.
Motoaki Tojo Ken Watanabe Kenichi Kida Yingjie Li Shuhei Numata 《Journal of General Plant Pathology》2007,73(2):121-124
Severe mottle necrosis (Shirogusare-byo in Japanese) was found on mature tubers of sweet potato (Ipomoea batatas) in Ibaraki Prefecture in October 2004. The causal organism was identified as Pythium scleroteichum hitherto unknown in Japan. Sweet potato cultivar Purple Sweet Lord was more susceptible than cultivars Beniazuma, Benimasari,
Koukei-14, and Tamayutaka to the pathogen at 25°C, while this difference in the susceptibility was not clear at 15°C. 相似文献
90.
矮生长豇豆的生育与产量形成 总被引:7,自引:1,他引:6
对春播和秋播矮生长豇豆的生长动态,叶面积形成与效能,结荚与豆荚产量形成特性等进行研究,结果表明,春播矮生长豇豆植株和各个器官的生长动态均呈S形曲线变化。秋播矮生长豇豆虽然无抽蔓期,但其生长动态与春播基本相同,而且植株生长和叶面积都较大,单株结荚稍多,但产量无明显差异。净同化率(NAR)在营养生长过程较高,生殖生长过程较低。本文还讨论了矮生与蔓生长豇豆生育与产量形成的差异。 相似文献