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11.
Biomechanics and Modeling in Mechanobiology - A characteristic feature of arthritic diseases is cartilage extracellular matrix (ECM) degradation, often orchestrated by the overexpression of matrix...  相似文献   
12.
The 5'-terminal sequence of hen ovalbumin mRNA was investigated using a novel labeling method. Ovalbumin mRNA was purified by hybridization to complementary DNA coupled to cellulose. The mRNA thus purified was shown to be 97.9% pure by hybridization with plasmid DNA containing sequences to the messengers coding for conalbumin and ovomucoid, the next two most abundant messengers of oviduct. After digestion with RNase T1 and alkaline phosphatase, 5'-terminal capped oligonucleotides were selected by binding to anti-m7G-Sepharose. These were then labeled using RNA ligase and [5'-32P]pCp, separated by two-dimensional gel electrophoresis, and sequenced by partial digestion with base-specific ribonucleases. A nested set of three capped oligonucleotides was identified. Their structures and relative abundances were m7GpppAUACAG, 3% m7GpppACAUACAG, 61+; and m7GpppGUACAUACAG, 36%.  相似文献   
13.
D Palm  G Münch  D Malek  C Dees  M Hekman 《FEBS letters》1990,261(2):294-298
Competition between Gs-protein and the synthetic peptide, GSA 379-394, derived from the carboxyl-terminal region of the alpha s-subunit, led to complete inhibition of receptor-mediated adenylate cyclase activation in turkey erythrocyte membranes. Related peptides corresponding to the homologous carboxyl-terminal region of alpha t-, alpha il- or alpha o-subunits did not interfere with beta-receptor-Gs coupling. The direct coupling between Gs and adenylate cyclase was not influenced by any of these peptides. These results emphasize the important role of the carboxyl-terminus of G-protein alpha-subunits for the specific recognition of their corresponding receptors and for signal transduction.  相似文献   
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The distribution of non-covalently bound secretory component (SC) on the two subclasses, IgA-f and IgA-g of rabbit secretory IgA (sIgA) was determined; the two subclasses were separated from each other by the use of antibody-immunosorbent columns and were subjected to SDS polyacrylamide gel electrophoresis. No SC appeared to be dissociated from the IgA-f molecules from each of 11 different rabbits; the IgA-g molecules, however, did have SC which was dissociated by SDS. Thus, all of the noncovalently bound SC on rabbit sIgA resides on the IgA-g subclass molecules.  相似文献   
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The International Journal of Life Cycle Assessment - This study has two aims: first, propose the use of the driver-pressure-state-impact-response (DPSIR) framework to expand the normal focus of...  相似文献   
18.
Highlights? Transformation-associated glucose shortage triggers ER stress ? The ER stress acts as barrier to malignancy by triggering UPR-dependent apoptosis ? p58IPK expression removes the UPR barrier by attenuating its PERK-CHOP branch ? This adaptive mechanism enables implementation of UPR cytoprotective features  相似文献   
19.
Cholangiocacinoma (CC) is a cancer disease with rising incidence. Notch signaling has been shown to be deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of CC is still not fully explored. In this study, we investigated the effects of Notch inhibition by γ-secretase inhibitor IX (GSI IX) in cultured human CC cell lines and we established a transgenic mouse model with liver specific expression of the intracellular domain of Notch (Notch-ICD) and inactivation of tumor suppressor p53. GSI IX treatment effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. In vivo overexpression of Notch-ICD together with an inactivation of p53 significantly increased tumor burden and showed CC characteristics. Conclusion: Our study highlights the importance of Notch signaling in the tumorigenesis of CC and demonstrates that additional inactivation of p53 in vivo.  相似文献   
20.

Background

Shigellosis continues to be a public health challenge for developing countries, including Bangladesh. The aim of the study is to demonstrate recent changes in Shigella sero-groups and their geographical diversity.

Methods

Data were extracted from data archive of four diarrheal disease surveillance systems. A 2% sub sample from urban Dhaka Hospital (2008–2011; n = 10,650), and 10% from urban Mirpur Treatment Centre (2009–2011; n = 3,585), were enrolled systematically; whereas, all patients coming from the Health and Demographic Surveillance System area in rural Matlab (2008–2011; n = 6,399) and rural Mirzapur (2010–2011; n = 2,812) were included irrespective of age, sex, and disease severity. A fresh stool specimen was collected for identification of Shigella spp. Of them, 315 (3%) were positive for Shigella in Dhaka, 490 (8%) from Matlab, 109 (3%) from Mirpur and 369 (13%) from Mirzapur and considered as analyzable sample size.

Results

Among all Shigella isolates regardless of age, significant decreases in percentage of S. flexneri over time was observed in Mirpur (55→29%; p value of χ2-for trend = 0.019) and Mirzapur (59→47%; p = 0.025). A non-significant decrease was also seen in Dhaka (58→48%), while in Matlab there was a non-significant increase (73→81%). Similar patterns were observed among under-5 children at all sites. Emergence of S. sonnei was found in Dhaka (8→25%; p<0.001) and Mirpur (10→33%; p = 0.015), whereas it decreased in Mirzapur (32→23%; p = 0.056). The emergence of S. boydii was seen in all ages in Mirzapur [(3→28%; p<0.001); (3→27%; p<0.001)]. On the other hand, we saw non-significant percent reductions in S. boydii in Dhaka [overall (25→16%); under-5 (16→9%)]. Decreasing rates of Shigella dysenteriae were observed in Matlab, Mirpur and Mirzapur; whereas, in Dhaka it remained unchanged.

Conclusion and Significance

Emergence of S. sonnei and S. boydii as important infectious diarrhea etiologies and variations in geographical diversity underscore the need for monitoring, with possible implications for vaccine development.  相似文献   
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