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31.
Th. Bittner J. Voigt G. Kehrberg H. -J. Eckert G. Renger 《Photosynthesis research》1991,28(3):131-139
Utilizing a two-beam technique in the frequency domain, the pumped absorption of PS II membrane fragments from spinach and of acetonic chlorophyll-a solutions was measured at room temperature. In a very narrow wavelength region (0.2 nm around the pump pulse wavelength) the relative test beam transmission exhibited either a decrease or an increase, respectively, dependent on the intensity of a strong pump beam. In contrast, the transmission changes of chl-a solutions were not affected by the wavelength mistuning between pump and test beam. The data obtained for PS II membrane fragments were interpreted in terms of excited state absorption of pigment-protein clusters within the light-harvesting complex of PS II. The interpretation of the small absorption band as a homogeneously broadened line led to a transversal relaxation time for chlorophyll in vivo of about 1 ps.Abbreviations PS I
photosystem I of green plants
- PS II
photosystem II of green plants
- P700
primary donor of PS I
- P680
primary donor of PS II 相似文献
32.
树干径流过程的动态响应模型 总被引:1,自引:0,他引:1
本文用实验测试法测量了干流过程。结果表明,干流过程曲线与R-L-C电路瞬态响应过程(包括输入、输出曲线)极为相似。据此,可用R-L-C电路瞬态响应过程曲线拟合干流过程,求出解析解。在计算机上调试参数,讨论其水文学意义,定性分析参数与影响干流因子的关系,取得了满意的结果。 相似文献
33.
Onychomycosis caused by Scopulariopsis brumptii 总被引:1,自引:0,他引:1
Scopulariopsis brumptii was isolated from nail lesions in left hand of a 42 year-old-farmer. The direct microscopic examination of the nail samples revealed light brown, septate, branched fungal hyphae along with thick-walled spherical cells. The histopathological examination showed involvement of internal phase of the nail plate. Amongst the antimycotics tested against S. brumptii In vitro oxiconazole was found to be the most active with MIC value of 10 g/ml–1. This report documents the first instance of onychomycosis caused by S. brumptii. 相似文献
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Summary A pot experiment with lettuce involving three N forms each at six application levels, showed that lettuce can be grown satisfactorily
with a very low nitrate content when supplied with ammonium sulphate and a nitrification inhibitor. For plants growing on
nitrate N, the optimum midrib sap nitrate concentration as maturity approached was about 1400 mg/1 NO3-N. Large losses of mineral N were observed from the peat medium, even in the absence of plants.
A relationship is presented which would enable a lettuce grower to estimate whole-shoot nitrate concentration from a quick
test of midrib sapi.e. NO3-N (mg/kg in fresh shoot) =0.14×NO3-N (mg/l in sap).
Tipburn was worst at intermediate levels of applied N, and was less serious with pure ammonium nutrition than with nitrate. 相似文献
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and
1986. Complete resistance to challenges with Hymenolepis nana cysticercoids derived from mouse, rat and beetle in mice. International Journal for Parasitology 16: 623–628. When BALB/c and dd strains of mice were given eggs of Hymenolepis nana, they all became completely resistant not only to challenge with mouse-derived cysticercoids but also to challenges with rat-derived and beetle-derived cysticercoids. Serum IgG antibodies at 47–60 days post egg inoculation reacted strongly with these three different host-derived cysticercoids when examined by IFA test, but IgA and IgM isotypes reacted very weakly. Antibodies of infected mouse sera (IgG, IgM and IgA were examined) reacted not only with the protoscolex (scolex of the excysted juvenile) but also with the outer cyst wall. By contrast, uninfected mouse sera and immune sera prepared seven days post cysticercoid inoculation did not react at all. Antigens of both cyst wall and protoscolex appeared to be of parasite origin and not of host origin, and appeared similar in parasites from the different host species. 相似文献
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在多年采集分离酵母菌的基础上,本文报道其中43属的600多株主要与担子菌有关的酵母及其他酵母的DBB反应,其中某些菌以往尚未测定过,从而广泛比较了担子菌酵母、子囊菌酵母与某些类酵母的区别。此外在方法上,摸索了其他未见报道的重氮盐的显色效果,发现固红B盐对布掷孢酵母(Bulleta Derx)的反应比DBB更灵敏。同时试验了热碱·乙醇处理细胞的快速DBB测试法,用此法测定某些疑难菌株,结果稳定,可大大缩短测试周期,并适用于多毛有气生菌丝的菌类。 相似文献
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