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91.
Apoptosis in development 总被引:50,自引:0,他引:50
Essential to the construction, maintenance and repair of tissues is the ability to induce suicide of supernumerary, misplaced or damaged cells with high specificity and efficiency. Study of three principal organisms--the nematode, fruitfly and mouse--indicate that cell suicide is implemented through the activation of an evolutionarily conserved molecular programme intrinsic to all metazoan cells. Dysfunctions in the regulation or execution of cell suicide are implicated in a wide range of developmental abnormalities and diseases. 相似文献
92.
Deciphering the evolution and metabolism of an anammox bacterium from a community genome 总被引:15,自引:0,他引:15
Strous M Pelletier E Mangenot S Rattei T Lehner A Taylor MW Horn M Daims H Bartol-Mavel D Wincker P Barbe V Fonknechten N Vallenet D Segurens B Schenowitz-Truong C Médigue C Collingro A Snel B Dutilh BE Op den Camp HJ van der Drift C Cirpus I van de Pas-Schoonen KT Harhangi HR van Niftrik L Schmid M Keltjens J van de Vossenberg J Kartal B Meier H Frishman D Huynen MA Mewes HW Weissenbach J Jetten MS Wagner M Le Paslier D 《Nature》2006,440(7085):790-794
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
93.
为寻找潜在的产生埃博霉素(epothilone)的纤维堆囊菌(Sorangium cellulosum),以埃博霉素生物合成基因簇中的epoA,epoC和epoK基因为探针,分别对60株不同土壤样品来源的纤维堆囊菌的DNA样品进行PCR筛选.筛选结果得到了7株阳性菌株,进一步对其进行发酵和粗提物的HPLC-MS分析,检测结果显示3株菌XMU-Nc-03,XMU-So-64和XMU-So-112能产生埃博霉素B,其中XMU-So-112的产量最高.本实验在筛选产埃博霉素活性菌株的同时,还建立了一个快速可靠的发现埃博霉素产生菌的方法. 相似文献
94.
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
95.
96.
The plant nuclear envelope 总被引:3,自引:0,他引:3
I. Meier 《Cellular and molecular life sciences : CMLS》2001,58(12-13):1774-1780
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
97.
Ohne Zusammenfassung 相似文献
98.
Karen Meier Reeds 《Annals of science》2013,70(6):519-542
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
99.
Ling Zhang Rolf Postina Yingqun Wang 《Cellular and molecular life sciences : CMLS》2009,66(24):3923-3935
Receptor for advanced glycation end products (RAGE) mediates diverse physiological and pathological effects and is involved
in the pathogenesis of Alzheimer’s disease (AD). RAGE is a receptor for amyloid β peptides (Aβ), mediates Aβ neurotoxicity
and also promotes Aβ influx into the brain and contributes to Aβ aggregation. Soluble RAGE (sRAGE), a secreted RAGE isoform,
acts as a decoy receptor to antagonize RAGE-mediated damages. Accumulating evidence has suggested that sRAGE represents a
promising pharmaceutic against RAGE-mediated disorders. Recent studies revealed proteolysis of RAGE as a previously unappreciated
means of sRAGE production. In this review we summarize these findings on the proteolytic cleavage of RAGE and discuss the
underlying regulatory mechanisms of RAGE shedding. Furthermore, we propose a model in which proteolysis of RAGE could restrain
AD development by reducing Aβ transport into the brain and Aβ production via BACE. Thus, the modulation of RAGE proteolysis
provides a novel intervention strategy for AD. 相似文献
100.
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