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排序方式: 共有1335条查询结果,搜索用时 15 毫秒
1.
A Rauch R A Pfeiffer G Leipold H Singer M Tigges M Hofbeck 《American journal of human genetics》1999,64(2):659-666
2.
Amy Chapman Gonzalo Gonzales Wayne R. Burrowes Paul Assanah Bernadette Iannone Michael K. Leung George B. Stefano 《Cellular and molecular neurobiology》1984,4(2):143-155
In Mytilus and Leucophaea the high-affinity binding site density is significantly lower in old animals than in young animals, whereas the low-affinity site density remains unchanged. In Mytilus the estimated met-enkephalin and met-enkephalin-Arg6-Phe7 levels are significantly higher in old than in young animals. In Leucophaea only the met-enkephalin level can be determined, and it is also higher in old animals. The decrease in the high-affinity binding site density and the corresponding increase in endogenous enkephalin levels suggest the existence of an opioid compensatory mechanism associated with the aging process. In Mytilus there is a demonstrated decrease with age in intraganglionic dopamine levels in response to applied opiates. In addition, the inhibition of dopamine-stimulated adenylate cyclase activity by opiates also decreases in older animals. In Leucophaea the sex difference in opioid binding densities diminishes with age. 相似文献
3.
4.
P. Mark Hogarth Margaret L. Hibbs Lisa Bonadonna Bernadette M. Scott Ewa Witort Geoffrey A. Pietersz Ian F. C. McKenzie 《Immunogenetics》1987,26(3):161-168
A cDNA clone encoding the mouse Ly-17+ Fc receptor for IgG, isolated from a myelomonocytic cell line, was sequenced and expression of mRNA and the functional FcR investigated. The receptor is a 301 amino acid transmembrane glycoprotein with two homologous extracellular domains that are also homologous to members of the Ig superfamily. The receptor has four sites of N-linked glycosylation and a long 94 amino acid cytoplasmic tail. Northern analysis, immune complex binding, and serological studies demonstrate that the receptor encoded by the cDNA clone binds mouse IgG1/2b and rabbit IgG complexes. 相似文献
5.
Human elongation factor 1α: a polymorphic and conserved multigene family with multiple chromosomal localizations 总被引:1,自引:0,他引:1
6.
Summary The study of gonadal organogenesis and differentiation by means of light and electron microscopy suggested the following in Helix aspersa: (1) the distal parts of the acini have components of mesodermal origin, whereas the neck and efferent duct comprise ectodermal elements; (2) a segregation of a germinal line occurs early, during the embryonic life; (3) in juvenile and adult animals, male and female cells arise from a germinal ring located at the base of the acinar neck. Apart from developing oocytes, the epithelium lining the distal region of the acini consists of somatic cells (Sertoli and follicle cells). 相似文献
7.
Endocytosis of a small dermatan sulphate proteoglycan. Identification of binding proteins. 总被引:2,自引:0,他引:2 下载免费PDF全文
Endosomal preparations from human osteosarcoma cells and from fibroblasts contain 51,000- and 26,000-Mr proteins which bind a small dermatan sulphate proteoglycan after SDS/polyacrylamide-gel electrophoresis and Western blotting. Binding can be inhibited by unlabelled proteoglycan core protein. The proteins co-precipitate with a proteoglycan core protein-antibody complex. Scatchard analysis of immobilized endosomal proteins yielded a KD of about 37 nM for the proteoglycan. In intact cells proteins of the same size can be found. They are sensitive to trypsinization. A 51,000-Mr protein is the predominant membrane protein with strong binding to immobilized dermatan sulphate proteoglycan. There are additional proteoglycan-binding proteins with Mr values of around 30,000 and 14,000 which are insensitive to trypsin treatment. In contrast with the 51,000- and 26,000-Mr proteins, they resist deoxycholate/Triton X-100 extraction several days after subcultivation. 相似文献
8.
Microsomal vesicles were prepared from zucchini (Cucurbita pepo L.) hypocotyls containing radioactive phosphatidylethanolamine or phosphatidylcholine, and these lipids were used as substrates by phospholipase A which is activated by auxins. Phospholipase D and phospholipase C hydrolysed the same substrates but were not influenced by auxin. Phospholipase A was activated by the auxins indolyl-3-acetic acid, 2,4-dichlorophenoxyacetic acid and, to a lesser extent, by -naphthaleneacetic acid whereas the weak auxins 2,3-dichlorophenoxyacetic acid and -naphthaleneacetic acid were almost inactive. This hormone specificity was also found in growth tests with etiolated zucchini hypocotyls. Phospholipase A activation by auxin was blocked by a polyclonal antibody against the maize auxin-binding protein. We propose that phospholipase A activation is a primary reaction in the signal transduction leading from hormone-binding to the growth response.Abbreviations IAA
indolyl-3-acetic acid
- 2,3-D, 2,4-D
2,3- and 2,4-dichlorophenoxyacetic acid
- -NAA; -NAA
- and -naphthaleneacetic acid
This work was supported by the Deutsche Forchungsgemeinschaft. We thank D. Klämbt (Botanical Institute, University of Bonn, FRG) for a generous gift of polyclonal antibody (IgG fraction) against auxin-binding protein and U. Kutschera (Botanical Institute, University of Bonn, FRG) for advice with the growth tests. 相似文献
9.
Shyam K. Sharan Bernadette Holdener-Kenny David W. Threadgill Terry Magnuson 《Mammalian genome》1992,3(2):79-83
Sensitive methods for analysis of DNA from limited amounts of tissue are often difficult, error prone, and time consuming. Here, we describe a procedure for molecular analysis of individual early post-implantation mouse embryos by Southern analysis. The procedure involves embedding single embryos in agarose before lysing and deproteinizing in situ. The embedded DNA can be digested with restriction enzymes and analyzed by standard Southern-blotting procedures. The procedure is sensitive enough to detect single-copy sequences in embryos as early as day 6.5 of development. We have used the technique to genotype embryos homozygous for an embryonic lethal deletion. Normally, the lethal phenotype associated with such mutations is identified by a retrospective statistical analysis of abnormal embryos produced from a heterozygous cross as compared to those produced from a control cross. Now, if associated with a detectable DNA abnormality, the mutant embryo can be genotyped directly. We also report the use of this method for mapping cloned markers relative to deletion breakpoints. This approach can save considerable time since mapping would conventionally be done using restriction fragment length polymorphisms (RFLPs) detected in Mus musculus/Mus spretus interspecies hybrids. Using this procedure, we have been able to redefine the distal limits of the region of Chromosome (Chr) 7 containing a gene (eed) needed for development of the embryonic ectoderm. 相似文献
10.
Eugene M. Rinchik Terry Magnuson Bernadette Holdener-Kenny Gavin Kelsey Albert Bianchi Claudio J. Conti Fran?ois Chartier Kathryn A. Brown Stephen D. M. Brown Josephine Peters 《Mammalian genome》1992,3(Z1):S104-S120
Chair of Committee for Mouse Chromosome 7 相似文献