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991.
992.
R. Siebert C. Willers W. Bardenheuer S. Michaelis A. Lux A. Schramm A. Gockel H. Luboldt B. Opalka J. Schütte 《Journal of cancer research and clinical oncology》1995,121(Z1):A36
contributed equally to this work 相似文献
993.
Molecular identification of T cells that respond in a primary bulk culture to a peptide derived from a platelet glycoprotein implicated in neonatal alloimmune thrombocytopenia. 总被引:3,自引:1,他引:2 下载免费PDF全文
Neonatal alloimmune thrombocytopenia induced by the human platelet alloantigen 1a (HPA1a) is characterized by generation of alloantibodies by a mother who is homozygous for the HPA1b alloantigen and almost always HLA-DRB3*0101. The disease is viewed as B cell mediated but the linkage with HLA is indicative of a role for T cells. The HPA1a and HPA1b allotypes are defined, respectively, by Leu and Pro at amino acid 33 of the beta-chain of the platelet integrin GPIIbIIIa (alpha(IIb)beta3). Under the assumption that the same polymorphism may control both the B cell epitope and constitute the MHC-bound peptide, we restimulated PBMC from a woman with an affected child with a synthetic peptide from this polymorphic region. Molecular analysis of the responding T cell repertoire identified two T cells which predominated in cultures stimulated with the alloantigen peptide and which were absent in cultures with the autoantigen peptide. In spite of the use of different V families, sequence of the CDR3 region of the T cell receptor (TCR) beta-chain revealed the presence of a shared motif, L-P-S/T. Oligonucleotide probes specific for the CDR3 sequence indicated that these T cells were present in the PBMC at the highest levels immediately after delivery of the affected infant and their frequency dropped at later times. 相似文献
994.
995.
Selection of Streptococcus pneumoniae Mutants Having Reduced Susceptibility to Moxifloxacin and Levofloxacin 下载免费PDF全文
With Streptococcus pneumoniae, moxifloxacin was 4- and 10-fold more effective than levofloxacin at restricting selection of resistant mutants and at killing resistant mutants, respectively. The selection frequency for first-step topoisomerase mutants was 1,000 times lower for moxifloxacin than for levofloxacin; this difference was lost when second-step mutants were selected. 相似文献
996.
Acid phosphatases 总被引:1,自引:0,他引:1
997.
998.
999.
1000.
P.-H.M. van der Kuy P.M. Hooymans A. Stegeman B.J. Looij jr 《Pharmacy World & Science》1997,19(4):208-209
The use of drugs to enhance performance in sport will continue despite drug testing procedures and information campaigns. No attention is paid to the quality of these illicit drugs, as they are obtained through a circuit not monitored by the official authorities. A falsification of 'Thai Dianabol', an anabolic steroid, is reported. The tablets contained methyltestosterone and clenbuterol instead of methandrostenolone. Two patients were admitted to the hospital with symptoms due to clenbuterol poisoning. 相似文献