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51.
L Prüfer-Kr?mer A Kr?mer R Weigel G R?gler B Fleige P H Krause E G Hahn E O Riecken H D Pohle 《The Journal of infectious diseases》1991,163(4):866-869
The effect of human immunodeficiency virus (HIV) infection on type and severity of liver disease was studied in 61 HIV-positive patients who did not have AIDS and in 45 AIDS patients. Liver biopsies revealed viral hepatitis in 12 of 18 non-AIDS patients but in only 4 of 34 AIDS patients (P less than .0005, Fisher's exact test). Acute, non-A non-B, and chronic active hepatitis B were seen exclusively in the non-AIDS group; however, chronic persistent hepatitis B was seen in both groups. In 9 of 18 AIDS patients intra vitam liver histopathology established diagnoses of opportunistic infections or tumors. Tissue reaction to certain pathogens, such as hepatitis B virus, mycobacteria, and cryptococci, seems to be milder in AIDS patients than in others who are HIV positive or the expected reaction of the normal host. This is likely because of impaired cell-mediated immunity in patients with advanced HIV disease. 相似文献
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Mundhenke C Weigel MT Sturner KH Roesel F Meinhold-Heerlein I Bauerschlag DO Schem C Hilpert F Jonat W Maass N 《Journal of cancer research and clinical oncology》2008,134(12):1397-1405
Purpose Imatinib is a small molecule inhibiting the tyrosine kinases bcr-abl, c-kit, PDGFR-α and PDGFR-β. Investigations were performed
to screen ovarian cancer cell lines and tumor samples for target receptor expression. Effects of Imatinib on cell proliferation
and apoptosis induction were measured with and without additional cytotoxic agents.
Methods Expression patterns of abl, c-kit, PDGFR-α and PDGFR-β (Imatinib targets) were studied in 5 cell lines and 111 tissue arrays
by PCR and immunohistochemistry. Proliferation assays were performed with single agent Imatinib or combined with Paclitaxel
and Carboplatin. Apoptosis was measured by DNA fragmentation.
Results All cell lines expressed abl and PDGFR-β. C-kit was only expressed in 2/5 cell lines and PDGFR-α in 4/5. Imatinib reduced
cell growth and lead to pro-apoptotic changes. Combination of Carboplatin, Paclitaxel and Imatinib showed synergistic activity.
Conclusions Our results suggest that Imatinib may be useful for the specific treatment of ovarian cancer as an add-on to conventional
chemotherapy.
C. Mundhenke and M. T. Weigel contributed equally to this work. 相似文献
54.
Filiault DL Wessinger CA Dinneny JR Lutes J Borevitz JO Weigel D Chory J Maloof JN 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(8):3157-3162
Plants have a sophisticated system for sensing and responding to their light environment. The light responses of populations and species native to different habitats show adaptive variation; understanding the mechanisms underlying photomorphogenic variation is therefore of significant interest. In Arabidopsis thaliana, phytochrome B (PHYB) is the dominant photoreceptor for red light and plays a major role in white light. Because PHYB has been proposed as a candidate gene for several quantitative trait loci (QTLs) affecting light response, we have investigated sequence and functional variation in Arabidopsis PHYB. We examined PHYB sequences in 33 A. thaliana individuals and in the close relative Arabidopsis lyrata. From 14 nonsynonymous polymorphisms, we chose 5 for further study based on previous QTL studies. In a larger collection of A. thaliana accessions, one of these five polymorphisms, I143L, was associated with variation in red light response. We used transgenic analysis to test this association and confirmed experimentally that natural PHYB polymorphisms cause differential plant responses to light. Furthermore, our results show that allelic variation of PHYB activity is due to amino acid rather than regulatory changes. Together with earlier studies linking variation in light sensitivity to photoreceptor genes, our work suggests that photoreceptors may be a common target of natural selection. 相似文献
55.
BJ Ferguson MD 《International forum of allergy & rhinology》2014,4(5):345-346
56.
Manavella PA Koenig D Weigel D 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(7):2461-2466
Processing of microRNA (miRNA) precursors results in the release of a double-stranded miRNA/miRNA* duplex. The miRNA or guide strand, is loaded onto the Argonaute (AGO) effector, and the miRNA* or passenger strand is typically degraded. The loaded AGO-containing RNA-induced silencing complex specifically recognizes a target mRNA, leading to its degradation or translational inhibition. In plants, miRNA-mediated cleavage of a target triggers in some cases the production of secondary small interfering RNAs (siRNAs), which in turn can silence other genes in trans. This alternative pathway depends on the length of the miRNA and the specific AGO in the effector complex. However, 22-nt miRNAs are sufficient, but not essential for this pathway. Using a combination of computational and experimental approaches, we show that transitivity can be triggered when the small RNA that is not retained in AGO is 22-nt long. Moreover, we demonstrate that asymmetrically positioned bulged bases in the miRNA:miRNA* duplex, regardless of miRNA or miRNA* length, are sufficient for the initiation of transitivity. We propose that the RNA-induced silencing complex reprogramming occurs during the early steps of miRNA loading, before the miRNA duplex is disassembled and the guide strand is selected. 相似文献
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59.
Marnie Preston PhD Xi Gong MD Weiping Su MD PhD Steven G. Matsumoto PhD Fatima Banine PhD Clayton Winkler PhD Scott Foster BS Rubing Xing BS Jaime Struve BS Justin Dean PhD Bruce Baggenstoss BS Paul H. Weigel PhD Thomas J. Montine MD PhD Stephen A. Back MD PhD Larry S. Sherman PhD 《Annals of neurology》2013,73(2):266-280
60.
Friederike Weigel Anja Lemke Burkhard Tönshoff Lars Pape Henry Fehrenbach Michael Henn Bernd Hoppe Therese Jungraithmayr Martin Konrad Guido Laube Martin Pohl Tomáš Seeman Hagen Staude Markus J. Kemper Ulrike John 《Pediatric nephrology (Berlin, Germany)》2016,31(6):1021-1028