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1.
T. Nagatsu T. Kato Y. Numata K. Ikuta M. Sano I. Nagatsu T. Takeuchi M. Matsuzaki H. Umezawa 《Cellular and molecular life sciences : CMLS》1977,33(5):581-583
Summary Serum dopamine--hydroxylase activity in spontaneously hypertensive rats and Wistar-Kyoto rats had a positive correlation with dopamine--hydroxylase and tyrosine hydroxylase activities in mesenteric vessels, vas deferens, and adrenal glands at 14–16 weeks of age, a negative correlation with dopamine--hydroxylase activity in locus coeruleus at 3 weeks and 14–16 weeks of age, and a positive correlation with tyrosine hydroxylase activity only at 3 weeks of age, but not at 14–16 weeks of age. 相似文献
2.
Summary Over three years, theAdh and -Gpdh loci have been studied in two cellar populations ofDrosophila melanogaster and in two field populations which were each near to one of the cellars. Analyses of gene frequencies indicate that the divergence among subpopulations is greater in theAdh locus than in the -Gpdh locus. Selection for or againstAdh
S
allele acting on theIn(2L)t inversion influences of the -Gpdh alleles. This phenomenon may contribute to explain the maintenance of theAdh and -Gpdh polymorphism and of theIn(2L)t inversion. 相似文献
3.
Peroxisomes are single-membrane-bound organelles present in virtually all eukaryotic cells. They are involved in numerous
metabolic processes, both catabolic and anabolic, including β-oxidation of very long chain fatty acids, metabolism of hydrogen
peroxide, plasmalogen biosynthesis and bile acid synthesis. In several genetic diseases, there is either isolated deficiency
of a specific peroxisomal protein (single-protein deficiencies) or a defect in the formation of the organelle with loss of
multiple peroxisomal functions (peroxisome biogenesis disorders). X-linked adrenoleukodystrophy is an example of the former,
and the Zellweger spectrum of the latter. Peroxisome biogenesis disorders are inherited in an autosomal recessive manner and
result from mutations in any of at least 12 PEX genes that encode peroxins. This article reviews the peroxisomal system, the clinical, biochemical and molecular aspects
of peroxisomal disorders, and discusses recent scientific advances in the understanding of peroxisome biogenesis.
Received 16 October 2001; received after revision 2 January 2002; accepted 3 January 2002 相似文献
4.
The correct repair of double-strand breaks (DSBs) is essential for the genomic integrity of a cell, as inappropriate repair
can lead to chromosomal rearrangements such as translocations. In many hematologic cancers and sarcomas, translocations are
the etiological factor in tumorigenesis, resulting in either the deregulation of a proto-oncogene or the expression of a fusion
protein with transforming properties. Mammalian cells are able to repair DSBs by pathways involving homologous recombination
and nonhomologous end-joining. The analysis of translocation breakpoints in a number of cancers and the development of model
translocation systems are beginning to shed light on specific DSB repair pathway(s) responsible for the improper repair of
broken chromosomes.
Received 19 June 2001; received after revision 6 September 2001; accepted 11 September 2001 相似文献
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6.
K. V. Nageswara Rao P. L. Narasimha Rao 《Cellular and molecular life sciences : CMLS》1961,17(5):213-214
Zusammenfassung Die Isolierung, Charakterisierung und antibiotischen Eigenschaften von-Guttiferin (I), C33H38O8 (Smp. 113–115°), aus den Samenhülsen und vom nahe verwandten-Guttiferin (II), C29H36O6 oder C33–34H38–40O8 (Smp. 86–91°) (möglicherweise identisch mit-Gambogasäure), aus Gummigutt, dem harzigen Sekret vonGarcinia morella, wurden beschrieben und ihre Verwandtschaft zu Morellin und Moreollin, den beiden bekannten Pigmenten der Samenhülsen, dargelegt. Für I wurde eine Partialstruktur vorgeschlagen. Die Bildung derselben komplexen bromhaltigen Säure vom Smp. 199 bis 200° unter der Einwirkung von Natriumhypobromit auf I und II spricht ferner für deren nahe strukturelle Verwandtschaft. 相似文献
7.
A. G. Terzian R. R. Safrasbekian R. S. Sukasian G. T. Tatevosian 《Cellular and molecular life sciences : CMLS》1961,17(11):493-494
Résumé L'-méthyltryptamine et le 5-méthoxy dérivé ont été synthétisés en utilisant une variante de la méthode d'Abramovitch etShapiro.Des expériencesin vitro ont montré que ces deux amines ne subissent pas de désamination par la monoaminoxydase du cerveau des rats blancs. La 5-méthoxy--methyltryptamine injectée aux souris blanches en dose de 10 mg/kg semble accroître l'activité de la monoaminoxydase du cerveau. 相似文献
8.
9.
J. E. Morris 《Cellular and molecular life sciences : CMLS》1962,18(12):567-568
Zusammenfassung Im Ei der AscidieHerdmania momus hebt sich nach der Besamung die Befruchtungsmembran von der äusseren Haut ab. Die Korrelationen, die bestehen zwischen Membranabhebung und Befruchtung, sowie ihrem Unterbleiben und der Sterilität, stützen wiederum die Chorionblocktheorie der Autosterilität. 相似文献
10.
《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2004,35(3):377-396
This paper describes a long-standing, though little known, debate between Dirac and Heisenberg over the nature of scientific methodology, theory change, and intertheoretic relations. Following Heisenberg's terminology, their disagreements can be summarized as a debate over whether the classical and quantum theories are “open” or “closed.” A close examination of this debate sheds new light on the philosophical views of two of the great founders of quantum theory. 相似文献
11.
S. P. Wolff 《Cellular and molecular life sciences : CMLS》1992,48(3):301-304
Although there is widespread agreement that many cancers have environmental causes we are often unable to see associations between specific cancers and exposure to environmental chemicals. One might also speulate that the more widespread, common-place and normal a chemical exposure is perceived to be then the less likely it will be that the exposure is recognised, let alone be considered to cause cancer. Widespread contamination of air by chemicals associated with internal combustion may be an example of one such invisible carcinogenic exposure. Yet evidence is available which suggests that many leukaemia and lymphoma cases, as well as other cancers, may be caused by this mundane and ubiquitous environmental contamination. The hypothesis is developed that leukaemia clustering as well as national leukaemia incidence may be related to non-occupational exposure to benzene formed by petrol combustion and resulting from petrol evaporation1. The possible association between exposure to fuel vapours, internal combustion products and cancer merits much closer examination than it receives at present. 相似文献
12.
J. A. Maclaren 《Cellular and molecular life sciences : CMLS》1961,17(8):346-347
Zusammenfassung Die früher als «Cystinmonosulfoxyd» beschriebene Verbindung (Thiosulfinat II) verhält sich wie eine äquimolekulare Mischung von Cystin (I) und dem entsprechenden Thiosulfonat (III). Oxydation von Cystin mit Perameisensäure führt, besonders in Gegenwart von HCl, über die Zwischenprodukte Thiosulfonat (III) und Sulfinsäure (VI) zu Cysteinsäure (VII). 相似文献
13.
Nakano A 《Cellular and molecular life sciences : CMLS》2004,61(2):186-191
The yeast Saccharomyces cerevisiae is one of the best-studied organisms to understand molecular mechanisms of membrane traffic, but as far as the organization of the Golgi apparatus is concerned, yeast is only just beginning to yield clues about how dynamic and flexible the organelle is. 相似文献
14.
δ-Protocadherins constitute a group of cadherins characterized by several conserved motifs in their cytoplasmic domains. We
present a phylogenetic analysis that further divides this group into δ1-protocadherins (comprising protocadherin-1, −7, −9
and −11 or -X/Y) and δ2-protocadherins (comprising protocadherin-8, −10, −17, −18 and −19). The δ-protocadherin genes, which
are located on different chromosomes in man and mouse, have a similar gene structure. They are expressed as multiple splice
forms, differing mostly in their cytoplasmic domains. Some δ-protocadherins were reported to mediate weak cell-cell adhesion
in vitro and cell sorting in vivo. In addition, individual δ-protocadherins might play important roles in signaling pathways,
as they bind to proteins such as TAF1/Set, protein phosphatase-1α and the Frizzled 7 receptor. The spatiotemporally restricted
expression of δ-protocadherins in different tissues and species and the results of their functional analysis, mainly in Xenopus, suggest that they play multiple, tightly regulated roles in vertebrate development.
Received 18 July 2005; received after revision 26 August 2005; accepted 2 September 2005 相似文献
15.
《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2002,33(2):185-210
In his search for a unified field theory that could undercut quantum mechanics, Einstein considered five-dimensional classical Kaluza–Klein theory. He studied this theory most intensively during the years 1938–1943. One of his primary objectives was finding a non-singular particle solution. In the full theory this search got frustrated, and in the x5-independent theory Einstein, together with Pauli, argued it would be impossible to find these structures. 相似文献
16.
Résumé L'acide-amino-butyrique et la-alanine reproduisent l'action du transmetteur inhibiteur du système neuromusculaire de l'écrevisse. Ces deux acids aminés diminuent la contraction musculaire. L'acide-amino-butyrique réduit la différence de potentiel et augmente sa décomposition. L'action de ces acides aminés est bloquée par la picrotoxine comme l'est celle du transmetteur inhibiteur.
The study was supported by Grants B-1089 and B-31 from the National Institute of Neurological Diseases and Blindness, United States Public Health Service. Some of this work was done at the Department of Zoology, Cornell University. We are grateful to Prof.S. C. Wang, Columbia University, for generous assistance. 相似文献
The study was supported by Grants B-1089 and B-31 from the National Institute of Neurological Diseases and Blindness, United States Public Health Service. Some of this work was done at the Department of Zoology, Cornell University. We are grateful to Prof.S. C. Wang, Columbia University, for generous assistance. 相似文献
17.
The formation of amyloid fibrils is associated with several devastating diseases in humans and animals, including e.g. Alzheimers disease (AD) and the spongiform encephalopathies. Here, we review and discuss the current knowledge on two amyloid peptides: lung surfactant protein C (SP-C) and the amyloid -peptide (A), implicated in human lung disease and in AD, respectively. Both these hydrophobic peptides are derived from the transmembrane region of their precursor protein, and can transit from a monomeric -helical state to a -sheet fibril. The helices of SP-C and A are composed of amino acid residues with inherently higher propensities for strand than helix conformation. Their helical states are stabilized by a membrane environment, and loss of membrane association thus promotes structural conversion and fibril formation. We speculate that the loss of structural context for sequences with a high propensity for formation of sheets may be a common feature of amyloid formation in general.Received 9 July 2003; received after revision 15 August 2003; accepted 3 September 2003 相似文献
18.
Y. Saleem T. Niveditha B. Sadasivudu 《Cellular and molecular life sciences : CMLS》1982,38(7):776-777
Summary AMP deaminase, 5-nucleotidase and adenosine deaminase have been estimated in skeletal muscle and myocardial tissue in normal rats and in rats subjected to experimental myocardial infarction or hypothermia. A difference in the enzyme distribution was found between the right and left ventricles in the normal rat. A decrease in the activity of 5-nucleotidase and an increase in the activity of adenosine deaminase were observed in infarcted myocardial tissue. The activity of all 3 enzymes was found to be depressed in the myocardium in rats subjected to hypothermia. These results are discussed in relation to adenosine production and its beneficial effects. 相似文献
19.
S. Agurell S. Carlsson J. E. Lindgren A. Ohlsson H. Gillespie L. Hollister 《Cellular and molecular life sciences : CMLS》1981,37(10):1090-1092
Summary Oral administration to man of 20 mg
11-tetrahydrocannabinol (THC) together with placebo or 40 mg cannabinol (CBN) or 40 mg cannabidiol (CBD) gave evidence of a possible limited interaction of THC with CBN but not with CBD as indicated by average plasma THC levels. Peak CBD and CBN concentrations were similar to that of THC, viz. about 5–8 ng/ml.Supported by the Swedish Medical Research Council and grant MH-00424 from the Veterans Administration. 相似文献
20.
D. J. McComb N. Ryan E. Horvath K. Kovacs I. Domokos F. A. Laszlo 《Cellular and molecular life sciences : CMLS》1979,35(10):1409-1410
Summary Following 2 weeks of administration of 2-bromo--ergocryptine, a marked decrease was observed in prolactin immunoreactivity of the grafted pituitaries, whereas no reduction was noted in the intrasellar pituitaries. No evidence of crinophagy was revealed by electron microscopy in prolactin cells of 2-bromo--ergocryptine-treated rats.Acknowledgments. This work was supported in part by the Medical Research Council of Canada (grant MA-6349). The excellent technical assistance of Mrs Cynthia Edwards and secretarial help of Mrs Wanda Wlodarski are gratefully acknowledged. 相似文献