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1.
Cloning of a cDNA for the FAD-linked glycerol-3-phosphate dehydrogenase from rat liver and its regulation by thyroid hormones. 总被引:2,自引:0,他引:2 下载免费PDF全文
S Müller H J Seitz 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(22):10581-10585
A full-length 2.4-kb cDNA for the FAD-linked glycerol-3-phosphate dehydrogenase (EC 1.1.99.5) was cloned from rat liver using PCR techniques. The cloned gene encodes a protein of 727 amino acids. The calculated molecular mass of 80,898 Da is higher than the apparent molecular mass observed by SDS/PAGE (74,000 Da) of the purified enzyme. This result indicates that the enzyme is synthesized as a precursor with a putative mitochondrial signal sequence. mRNA for this gene was detected in liver, heart, muscle, brain, testes, and pancreas. With the exception of testes, basal expression levels were very low in all tissues examined. However, application of thyroid hormones led to a 10- to 15-fold increase in liver glycerol-3-phosphate dehydrogenase mRNA, whereas hypothyroidism further decreased the mRNA level. 相似文献
2.
Manuela Kusch Claudia Grundmann Stefanie Keitel Rainer Seitz Herbert K?nig 《Blood coagulation & fibrinolysis》2006,17(7):575-580
A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases. 相似文献
3.
Walter F. McKeever Karen S. Seitz Annette J. Krutsch Patti L. Van Eys 《Neuropsychologia》1995,33(12):1627-1635
Rasmussen and Milner [N.Y. Acad. Sci. Vol. 299, pp. 355–379, 1977] published data on late-lesioned (after age 6) epileptic patients who had suffered left hemisphere lesions. They estimated that left hemisphere dominance occurred in 96% of dextrals and 70% of sinistrals. These figures have been regarded as valid estimates for normal dextrals and sinistrals. We administered the Bilateral Object Naming Latency Task, a verbal tachistoscopic task with very good psychometric properties, to 188 dextral and 72 sinistral normals. Results showed that 93.6% of the dextrals and 80.3% of the sinistrals were left hemisphere dominant. A consideration of results from a number of carefully conducted dichotic listening studies suggests, as do present results, that the 70% left-dominance estimate of Rasmussen and Milner for normal sinistrals may be too low by about 10%. It is suggested that ‘bilateral dominance’, present in 15% of the epileptic sinistrals of Rasmussen and Milner, may be much less common in normal sinistrals. 相似文献
4.
Thilo Klindert Isabel Stroetmann Gunther Seitz Georg Hfner Klaus Th. Wanner Gerlinde Frenzen Brigitta Eckhoff 《Archiv der Pharmazie》1997,330(6):163-168
A number of novel pyridazinomorphinans have been synthesized by the inverse electron demand Diels-Alder reaction of various 3,6-disubstituted 1,2,4,5-tetrazines with enamines derived from dihydrocodeinone and with codeinone. Reduction of some of the pyridazinomorphinans did not furnish the expected pyrroloepoxymorphinans; in all cases investigated reductive cleavage of the epoxybridge was observed to yield dihydropyridazino- or pyrrolomorphinans. The structures of all new compounds were assigned by the spectral data, that of the cycloadduct of codeinone was additionally verified by X-ray crystallography. Compounds 5a, 8, 11a , and 16 have been evaluated for their affinity at μ and κ opioid receptors in radioligand binding assays. Their ability to inhibit [3H]DAMGO binding at μ and [3H]U 69.593 binding at κ receptors, respectively as compared to codeine has been found to be lower. 相似文献
5.
C Bohm T Greitz R Seitz L Eriksson 《Journal of cerebral blood flow and metabolism》1991,11(2):A64-A68
The computerized individually adjustable brain atlas (CBA) has been further developed. The atlas was primarily designed for anatomical localization and quantitative evaluation of data in positron emission tomography (PET), but may also be employed for other neuroimaging modalities, such as transmission computed tomography (CT) and magnetic resonance imaging (MRI). The atlas is based on anatomical information obtained from digitized cryosectioned brains. Using spatially standardized and then averaged MRI images, we demonstrate the high localization accuracy and precision of the brain atlas. This is a prerequisite for obtaining accuracy when using the atlas in the localization and the quantitative evaluation of PET data. The specification and the selection of region of interests (ROIs) by the CBA are presented and discussed. 相似文献
6.
Both cefotiam and ceftizoxime stimulate the uptake of gonococci by polymorphonuclear granulocytes in vitro as can be seen by light microscopy. Although this already holds true of antibiotic concentrations lower than the minimum inhibitory concentration (MIC: 1/4 x) this effect is much more marked at concentrations highly exceeding the MIC (4000 x). As light microscopic investigation allows the analysis of large numbers of cells but no final judgement on actual bacterial engulfment definite phagocytosis is demonstrated by electron microscopy. 相似文献
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9.
Between 1976 and 1989, 53 out of 60 patients with large cell carcinoma of the lung underwent potentially curative surgery, i.e. macroscopically and microscopically complete resection. For better comparison, all tumors were classified according to the TNM staging system of the UICC 4th edition of 1987. Following potentially curative surgery, in stage I the mean survival time was 19 months and the five-year survival rate 30.1%, in stage II 8 months and 10%, and in stage IIIa 6.5 months and 0%, respectively. The differences in the long term prognosis between the tumor stages are significant. No significant differences could be demonstrated between II and IIIa in terms of the mean survival times. The prognosis for patients with potentially curatively resected squamous cell carcinoma is significantly better than that for patients with large cell carcinoma. 相似文献
10.
Thromboxane B2 synthesis in human platelets induced by the late complement components C5b-9 总被引:2,自引:0,他引:2
M Betz M Seitz G M H?nsch 《International archives of allergy and applied immunology》1987,82(3-4):313-316
Sublytic doses of purified C5b6, C7, C8 and C9 induce the release of thromboxane B2 (TXB2) in human platelets. In the present study, we attempted to analyze the signal by which C5b-9 triggers the prostanoid synthesis in platelets. TXB2 release was accompanied by liberation of Ca++ from intracellular stores. Influx of Ca++ was not observed, indicating that C5b-9 did not form a channel large enough to permit passage of Ca++ ions. Therefore, channel formation is apparently not required for cell stimulation. 相似文献