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871.
This work present a short and simple method for mutation detection in type I collagen genes, based on the direct sequencing of single-stranded DNA. The sequencing of type I collagen genes is complicated and difficult because of their large size and highly repetitive and GC-rich coding regions. Although many techniques have been developed for mutation screening in osteogenesis imperfecta (OI), they represent different degrees of sensitivity and are difficult to reproduce and too expensive for application in each laboratory. The method described here is short, easy and especially useful for sequencing of collagen genes in OI cases, in which the region with a suspected structural defect is localized by collagen analysis. 相似文献
872.
STOCKS: STOChastic Kinetic Simulations of biochemical systems with Gillespie algorithm 总被引:2,自引:0,他引:2
Kierzek AM 《Bioinformatics (Oxford, England)》2002,18(3):470-481
873.
874.
875.
Pierre Devaux Andrzej Kilian Andris Kleinhofs 《Molecular genetics and genomics : MGG》1993,241(5-6):674-679
Anther culture and Hordeum bulbosum-derived doubled haploid (DH) lines of barley (Hordeum vulgare L.) were analyzed for RFLP and RAPD polymorphisms. Polymorphisms were not detected in the anther culture-or H. bulbosum-derived DH lines among 273 RFLP and 89 polymerase chain reaction (PCR)-amplified DNA fragments assayed. It was calculated that base substitution or small deletion/insertion mutations had not been induced among 401 640 by screened. Large deletion/insertion mutations were not observed among 33 Mb screened. Polymorphisms were observed when DNA was digested with the methylation-sensitive restriction enzymes HpaII and MspI: these RFLPs originated primarily from the anther culture-derived doubled haploids. The data indicate that heritable DNA methylation changes had occurred during DH production, particularly with the anther culture method. 相似文献
876.
Michal Janitz Dorota Fiszer Karolina Michalczak-Janitz Andrzej Lukaszyk Nelson Fernandez Witold Skorupski Maciej Kurpisz 《Molecular reproduction and development》1994,38(2):231-237
We have studied mRNA expression for Class I HLA (human leukocyte antigen) on male germ cells by amplification of gene fragments in PCR techique and by Northern hybridization. RNA was extracted from fractionated gametogenic cells (isolated from testis) and reversely transcribed. Then, cDNA was amplified for specific HLA sequence (1151 bp) representing whole-length coding sequence (HLA, -A, -B, -C). The specificity of this product was confirmed in “nested” PCR of 400 bp gene fragment coding for alpha 2 domain, alpha 3 domain, and the transmembrane portion of Class I HLA. The results indicate minimal expression of classical Class I HLA on gametogenic cells. Northern hybridization with 669 bp cDNA fragment (spanning for alpha 3 domain, transmembrane, cytoplasmic, and 3′ untraslated region) resulted in a low intensity signal from gametogenic cell fractions and confirmed our findings obtained by PCR. The minimal expression of classical HLA antigens may create a neutral cover for the male reproductive system, thereby preventing an immunological response during germ cell differentiation. © 1994 Wiley-Liss, Inc. 相似文献
877.
The food and cellulase activity of five cyprinid and one salmonid species were examined. All Cyprinidae species showed cellulase activity. No activity was found in pelagic Coregonus albula (Salmonidae). Cellulase activity showed a positive correlation with the amount of highly processed plant detritus in the gut. No correlation was found between the activity level and the amount of fresh fragments of macrophytes and filamentous algae. 相似文献
878.
Andrzej Markiewicz 《Chronobiology international》1992,9(6):453-461
This review is intended to present our knowledge on both chronomorphology and chronophysiology of jejunum mainly in humans, as well as on implications of chronobiologic principles in the practice of gastroenterology. 相似文献
879.
Leszczynski Przemyslaw Hendrich Andrzej Boguslaw Szmida Elzbieta Sasiadek Maria Malgorzata 《BMB reports》2013,46(3):139-150
The ADAM and ADAMTS families, also called adamalysins belong to an important group of extracellular matrix proteins. The ADAMs family belong to both the transmembrane and secreted proteins, while ADAMTS family only contains secreted forms. Adamalysins play an important role in the cell phenotype regulation via their activities in signaling pathways, cell adhesion and migration. The human proteome contains 21 ADAM, and 19 ADAMTS proteins, which are involved in extracellular matrix remodeling, shedding of various substrates such as: adhesion ligands, growth factors, their receptors and diverse cytokines. Recent studies provide evidence that adamalysins play a crucial role in colorectal cancer (CRC) etiopathogenesis. It seems possible that adamalysins might be used as CRC prediction markers or potential pharmaceutical targets. [BMB Reports 2013; 46(3): 139-150] 相似文献
880.
Ivan Tattoli Andrzej Grajkowski Assaf Levi Beverly H Koller Irving C Allen Serge L Beaucage Katherine A Fitzgerald Jenny P ‐Y Ting John C Cambier Stephen E Girardin Christian Schindler 《EMBO reports》2013,14(10):900-906
The cyclic dinucleotides 3'‐5'diadenylate (c‐diAMP) and 3'‐5' diguanylate (c‐diGMP) are important bacterial second messengers that have recently been shown to stimulate the secretion of type I Interferons (IFN‐Is) through the c‐diGMP‐binding protein MPYS/STING. Here, we show that physiologically relevant levels of cyclic dinucleotides also stimulate a robust secretion of IL‐1β through the NLRP3 inflammasome. Intriguingly, this response is independent of MPYS/STING. Consistent with most NLRP3 inflammasome activators, the response to c‐diGMP is dependent on the mobilization of potassium and calcium ions. However, in contrast to other NLRP3 inflammasome activators, this response is not associated with significant changes in mitochondrial potential or the generation of mitochondrial reactive oxygen species. Thus, cyclic dinucleotides activate the NLRP3 inflammasome through a unique pathway that could have evolved to detect pervasive bacterial pathogen‐associated molecular patterns associated with intracellular infections. 相似文献