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981.
Zinc-finger transcription factors in plants   总被引:2,自引:0,他引:2  
  相似文献   
982.
Perinatal asphyxia (PA) is considered to lead to a variety of brain disorders including spasticity, epilepsy, mental retardation, and minimal brain disorder syndromes and may form the basis for psychiatric and neurodegenerative diseases later in life. We examined markers for neuronal transmission involved in the pathomechanisms of PA and candidates as mediators for long-term sequelae. We tested tyrosine hydroxylase (TH) and the vesicular monoamine transporter (VMAT) representing the monoaminergic system, the vesicular acetylcholine transporter (VAChT), and the excitatory amino acid carrier 1 (EAAC1), a neuronal subtype of the glutamate transporter, using immunohistochemistry on brain sections of rats subjected to graded PA. Three months following the asphyxiant insult immunoreactive (IR)-TH was decreased in striatum, hippocampus, thalamus, frontal cortex, and cerebellum; IR-VMAT was increased, and IR-VAChT was decreased in striatum. IR-EAAC1 glutamate transporter was increased in frontal cortex. The cholinergic, monoaminergic, and glutamatergic changes, still observed 3 months after the asphyxiant insult, may reflect their involvement in the pathomechanisms of PA and indicate mechanisms leading to long-term complications of PA. The variable consequences on the individual markers in several brain regions may be explained by specific susceptibility of cholinergic, monoaminergic, and glutamatergic neurons to the asphyxiant insult. Received 16 March 1999; received after revision 20 May 1999; accepted 8 July 1999  相似文献   
983.
Twelve cosmids containing sequences resembling genes encoding members of the 70-kDa heat-shock protein family, HSP70, have been isolated from Fugu rubripes. They can be broadly divided into three groups of overlapping cosmids. Restriction analysis and sequencing of one set of five cosmids have revealed five intronless Fugu HSP70 genes spanning 42 kb, arranged in a combined head-to-head, tail-to-tail and head-to-tail orientation. The levels of DNA and amino acid identity are very high with respect to one another, and are most similar to HSP70 sequences linked to the major histocompatibility complex (MHC) region in other species. Putative heat-shock consensus elements are identified. Non-HSP70 sequences with homology to known genes have been found physically linked to this Fugu HSP70 cluster: the Drosophila melanogaster SOL gene, the Drosophila melanogaster nemo gene, the Caenorhabditis elegans T17E9.1 gene and the sequence encoding the serine protease domain. The linkage relationships described here so far bear no resemblance to those of HSP70 in other organisms. Convergence of mammalian HSP70 and MHC class I and II loci probably occurred after fish had diverged. Received 17 November 1998; received after revision 25 February 1999; accepted 26 February 1999  相似文献   
984.
Summary Fine divided HF-etched quartz was dissolved in a 0.2M solution of pyrocatechol at pH 9.6. Between 17 and 40 °C the dissolution rate (v s ) follows the equation: logv s =0.0295 T-20.87 At 25 °Cv s amounts to 0.8 · 10–12 g cm–2 sec–1. With several phenols the dissolution rate of quartz decreases in the order: pyrocatechol > pyrogallol > 2, 3-dihydroxynaphthalene.  相似文献   
985.
986.
Zusammenfassung Die Struktur destrans-6-[2-(1-hydroxybutyl)-4-tolyl]-hex-5-enamids (I), eines neuen mikrobiellen Metaboliten, wurde durch Protonenresonanz-Spektroskopie unter Verwendung des Verschiebungsreagenz Eu (DPM)3 bestimmt.  相似文献   
987.
This paper describes the introduction of Liebig's ideas on agricultural chemistry into the Netherlands. The aversion to Liebig held by the Utrecht professor G. J. Mulder hindered the direct influence that might have been borne by Liebig's own writings; the introduction was made principally by means of Dutch translations of the text-books of the Scottish agricultural chemist J. F. W. Johnston, who generally followed Liebig's ideas.  相似文献   
988.
989.
H J?rnvall 《Nature》1970,225(5238):1133-1134
  相似文献   
990.
Summary Serotonin and 5-hydroxyindoleacetic acid (5-HIAA) were measured in individual nuclei of rat hypothalamus and other brain areas using HPLC with electrochemical detection. 5-HIAA levels were first demonstrated in hypothalamic and some discrete brain areas. The 5-HIAA/5-HT ratio was highest in the n. caudatus putamen, high in the n. ventromedialis and lowest in the n. suprachiasmaticus.  相似文献   
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