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91.
以6个不同产地的2种化学型广藿香叶片为试材,采用数码显微系统对叶片的多种显微特征进行观察比较,采用SPSS 21.0、MEGA 7、SIMCA 14.1软件进行脉岛数、栅表比、气孔指数、非腺毛数、头状腺毛数、盾状腺毛数显微常数的方差分析、聚类分析和主成分分析试验,以期为广藿香叶片显微特征与化学型分型的研究及广藿香品质评价提供参考依据。结果表明:2种化学型广藿香叶表皮细胞形状、表皮细胞长宽比、气孔大小及类型相近;叶缘、叶长宽比、垂周壁形状、表皮细胞大小、栅表比、脉岛数、气孔指数、非腺毛数、头状腺毛数、盾状腺毛数差异显著,可以作为区分广藿香不同化学型的评判指标;四会、高州、雷州、阳春4个产地的广藿香归为一类,均为醇型,莲塘、龙洞产地归为一类,均为酮型。 相似文献
92.
The clinical, biochemical, histological, or ultrastructural abnormalities of five related female Rottweiler dogs with a hereditary disorder of cornification are reported. Three of the five dogs also had multiple noncutaneous congenital defects. Cutaneous abnormalities included generalized, hyperkeratotic, variably pigmented plaques, which in one dog were distributed along Blaschko's lines. Moderate to severe parakeratosis involving the follicular infundibula and ostia and focal orthokeratosis with variable vacuolation of spinous cells was observed on histopathologic examination of all skin specimens. Supplementation with oral zinc in two dogs and vitamin A alcohol and calcitriol in one dog did not result in clinical or histological improvement of the hyperkeratotic lesions. This disorder of cornification in dogs is similar to human disorders of cornification that follow the lines of Blaschko. Blaschko's lines follow a V-shape over the spine, an S-shape on the abdomen, and an axial distribution on the limbs. No related male dogs were affected, suggesting an X-linked dominant mode of inheritance. Many features of this hereditary DOC correspond to the human condition CHILD syndrome. 相似文献
93.
A. Sivasankark K. C. Lakkineni Vanita Jain P. A. Kumar Y. P. Abrol 《Journal of Agronomy and Crop Science》1998,181(2):65-70
Two wheat genotypes, viz. Uniculm 'Gigas' (V1) and Kalyansona (V2) were raised to maturity under two levels of nitrogen supply @ 30 (N1) and 120 (N2) kg ha−1 , under pot culture conditions. Laminae numbering 1 to 8 on the shoot were examined for area, net photosynthetic rate ( P n ) and mesophyll cell characteristics, at full expansion. N1 resulted in greater reduction in the area of upper laminae in V1 than in V2. The flag and penultimate laminae maintained similar P n rates at both N levels in V1 despite a large reduction in area at N1. However, V2 exhibited about 25% reduction in P n rates of the flag laminae at N1 as compared with N2. Mesophyll cell number per unit area gradually increased with laminae order in the genotypes. The greater number of mesophyll cells in the upper laminae was essentially due to a reduction in cell size and surface area as a result of low N availability. The large differences in laminae size due to N treatments, particularly in V1, are attributed to mesophyll cell numbers. However, the maintenance of P n rates in V1, even at low N supply, is a possible outcome of higher activity of the mesophyll cell constituents in this genotype. 相似文献
94.
麦类作物的叶片单细胞瞬间表达是一种高效而快速的基因功能验证方法,尤其适用于麦类作物与白粉病菌的互作系统,但由于影响参数较多、参检基因表达频率低而尚未广泛应用。本研究使用绿色荧光蛋白(GFP)基因作为报告基因,对影响表达效率的多个转化参数进行优化,筛选出表达频率最高的参数组,即小麦叶片采用固体保鲜培养基固定,钨粉用量为每枪300μg,质粒DNA用量为每枪750ng,可裂膜氦压为1 350psi,可裂膜与受体膜距离6mm,受体与阻挡网距离6cm,与先前报道的方法相比表达频率有显著提高。应用上述参数在感病小麦品种离体叶片中过量表达一个已知具有抗白粉病功能的簇毛麦SGT1基因,结果表明该基因瞬间表达使互作细胞吸器指数降低,表现为对白粉病菌侵入和吸器形成具有抑制作用,在一定程度上增强了表达细胞对白粉病菌的抗性,使目标基因的抗性功能再次得到印证。本研究还进一步运用该优化体系开展瞬间表达介导的基因沉默(TIGS)实验,将携带抗白粉病基因Pm21的抗病小麦品种南农9918和感病小麦品种扬麦158中的内源SGT1和RAR1分别或同时沉默,结果显示南农9918的叶片表皮与白粉菌互作细胞的吸器指数增高,在一定程度上降低了表达细胞对白粉菌的抗性。而扬麦158中互作细胞的吸器指数较对照变化不显著。说明这两个基因均分别参与了Pm21介导的抗白粉病信号途径,且二者共同作用与白粉病抗性关系更加密切。 相似文献
95.
Wuersch K Brachelente C Doherr M Reist M Sattler U Forster U Bertoni G Peel JE Welle M 《Veterinary immunology and immunopathology》2006,110(3-4):311-323
BACKGROUND: Flea allergy dermatitis (FAD) is a common skin disease in dogs and can be induced experimentally. It often coexists with other allergic conditions. So far no studies have investigated the quantitative production of cytokine mRNA in skin biopsies and peripheral blood mononuclear cells (PBMC) in flea allergic dogs. OBJECTIVE: The aim of our study was to improve the understanding of the immunopathogenesis of allergic dermatitis as a response to fleabites. MATERIAL AND METHODS: Allergic and non-allergic dogs were exposed to fleas. Before and after 4 days of flea exposure mRNA was isolated from biopsies and PBMC. Production of chymase, tryptase, IL-4, IL-5, IL-13, TNF-alpha and IFN-gamma mRNA was measured by real-time RT-PCR. The inflammatory infiltrate in the skin was scored semi-quantitatively. The number of eosinophils, mast cells (MC) and IgE+ cells/mm2 was evaluated to complete the picture. RESULTS: FAD was associated with a higher number of MC before flea exposure and with a significant increase of eosinophils after flea exposure as compared to non-allergic dogs. The number of IgE+ cells was higher in allergic dogs before and after flea exposure. In allergic dogs mRNA for most cytokines and proteases tested was higher before flea exposure than after flea exposure. After exposure to fleas an increased mRNA production was only observed in non-allergic dogs. In vitro stimulation with flea antigen resulted in a decreased expression of most cytokines in allergic dogs before flea exposure. In contrast, in PBMC, only increased levels of IL-4 and IL-5 mRNA were observed in allergic dogs before flea exposure. However, after flea exposure and additional stimulation with flea antigen the production of mRNA for all cytokines tested was significantly increased in allergic dogs. CONCLUSION: We demonstrated that the response in biopsies and PBMC is different and that FAD is associated with a TH2 response. 相似文献
96.
97.
以白魔芋等4种魔芋资源为材料,对其裂片及表皮细胞进行形态学比较研究,结果表明:白魔芋裂片披针形,尖端长尾状,钝齿状叶缘,表皮细胞含丰富内含物;花魔芋裂片卵圆形,尖端渐尖,基部左侧偏大,叶缘浅波状,气孔器呈平行型排列;珠芽魔芋裂片椭圆形,皱波状叶缘,基部盾圆,表皮细胞为4种资源最大;甜魔芋裂片卵状三角形,尖端盾尖,气孔器呈不等型排布. 相似文献
98.
A mutant of oilseed rape (B. napus L.) with waxless leaves was discovered in 1988. Three pairs of reciprocal crosses were made between the mutant (Wl) and 3 normal wax layered lines (Nwl). By the summer planting in Kunming and Wenjiang and the autumn planting in Wenjiang, it was confirmed that the Wl character is completely dominant to the normal opposite Nwl. Chi-square tests revealed that the segregation ratios of Wl to Nwl among B1 and F2 plants fit to 1:1 and 3:1, respectively, i.e. the assumption of one gene pair. The yield of 12 hybrids, which were derived fom Wl and some Nwl lines, exceeded the check control ‘Zhong You 821’, a best cultivar in Chinese production by 19.31 % on the average. When the seedling had 3–4 leaves, both phenotypes can be accurately determined visually on the field. This material possesses potential value for studies of the genetics and breeding, as a prominent genetic marker in B. napus. 相似文献
99.
100.
猪乳中常规成分、胰鸟素和表皮生长因子浓度的动态变化 总被引:4,自引:1,他引:3
选择8头3~4胎、产仔9~13头的健康大长北(大约克×长白×北京黑猪)母猪,对其分娩后35d泌乳期内初乳和常乳中的常规成分、胰岛素和表皮生长因子进行了动态分析。结果表明,母猪刚分娩时其初乳中乳蛋白、总固型物、胰岛素和表皮生长因子的浓度均高于常乳(P<0.05),乳糖和乳脂则随泌乳期延长而增加,分娩后3d内这种变化显著(P<0.05),而常乳中则变化不明显。 相似文献