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61.
Anaerobic ammonium oxidation (anammox) has become a main focus in oceanography and wastewater treatment. It is also the nitrogen cycle's major remaining biochemical enigma. Among its features, the occurrence of hydrazine as a free intermediate of catabolism, the biosynthesis of ladderane lipids and the role of cytoplasm differentiation are unique in biology. Here we use environmental genomics--the reconstruction of genomic data directly from the environment--to assemble the genome of the uncultured anammox bacterium Kuenenia stuttgartiensis from a complex bioreactor community. The genome data illuminate the evolutionary history of the Planctomycetes and allow us to expose the genetic blueprint of the organism's special properties. Most significantly, we identified candidate genes responsible for ladderane biosynthesis and biological hydrazine metabolism, and discovered unexpected metabolic versatility.  相似文献   
62.
M Meier  U Steppuhn  W Rück 《Experientia》1979,35(10):1342-1343
Up to now the problem of classifying squirrel monkey vocalizations has not been solved satisfactorily. The problems is now approached by a method, which consists of 2 phases. At first the monkey vocalizations are compared with the aid of physical criteria and classified by types. According to the classification of types, the membership of the individual vocalizations is tested.  相似文献   
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The plant nuclear envelope   总被引:3,自引:0,他引:3  
This review summarizes our present knowledge about the composition and function of the plant nuclear envelope. Compared with animals or yeast, our molecular knowledge of the nuclear envelope in higher plants is in its infancy. However, there are fundamental differences between plants and animals in the structure and function of the nuclear envelope. This review will compare and contrast these differences for nuclear pore complexes, nuclear transport, inner nuclear envelope proteins and the role of the nuclear envelope during mitosis. In some cases, seemingly 'novel' aspects of plant nuclear envelope function may provide new insight into the animal cell nucleus.  相似文献   
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The enthusiasm of Renaissance humanists for classical learning greatly influenced the development of botany in the late fifteenth and sixteenth centuries. Humanist scholars restored the treatises of Theophrastus, Pliny, Galen and Dioscorides on botany and materia medica to general circulation and argued for their use as textbooks in Renaissance universities. Renaissance botanists' respect for classical precepts and models of the proper methods for studying plants temporarily discouraged the use of naturalistic botanical illustration, but encouraged other techniques for collecting and communicating new observations: herbaria, botanical gardens and field trips.  相似文献   
67.
Summary A new simple method for the production of experimental hypertension has been developed. Anoxæmia of the kidney has been produced by encapsulating the organ in tubes of acetyl cellulose. Development and degree of hypertension is directly depending on the ratio between size of kidney and tube, so that standard size tubes for definite animal weight may be used with high percentage of success.  相似文献   
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Summary A post-incubation with 1% sulfanilic acid solution in 10% CH3COOH (approx. 2–10 min) or 5–10% potash alum or 0.5 mol AlCl3 in 0, 1n HCl-after the histochemical reaction with diazonium salt-prevents N2 formation. This gas originates from decomposition of tissue adsorbed diazonium salt which occurs after mounting in glycerin jelly. The inhibition of diazo-group disintegration depends, in the case of sulfanilic acid, on the formation of a diazoamino compound or double salt production with aluminium ions in the case of AlCl3.  相似文献   
70.
Summary Various croton oil fractions were studied with regard to theirin vitro effect on leucocytes and their irritative action. It was discovered that there exist fractions exerting a stimulating effect on leucytic migration and an irritative action and other fractions having a leucocytic stimulating effect without pronounced irritative action. The co-carcinogenic fractions ofDanneel have no promotory effect on the migration of leucocytes.  相似文献   
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