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排序方式: 共有160条查询结果,搜索用时 656 毫秒
91.
Anke Wesselius Martijn JL Bours Niklas R Jørgensen James Wiley Ben Gu Svenjhalmar van Helden Lodewijk van Rhijn Pieter C Dagnelie 《Purinergic signalling》2013,9(1):123-130
In the present study we investigated whether single nucleotide polymorphisms (SNPs) in the P2RX4, which alter the P2X4R function, are associated with the development of osteoporosis and whether an interaction between the P2X4R and P2X7R confer a synergistic effect of these two receptors on osteoporosis risk. Patients with fracture (690 females and 231 males, aged ≥50 years) were genotyped for three non-synonymous P2X4R SNPs. Bone mineral density (BMD) was measured at the total hip, lumbar spine, and femoral neck. Subject carrying the variant allele of the Tyr315Cys polymorphism showed a 2.68-fold (95 % CI, 1.20–6.02) higher risk of osteoporosis compared with wild-type subject. Furthermore, significant lower lumbar spine BMD values were observed in subjects carrying the Cys315 allele as compared with wild-type (0.85 ± 0.17 and 0.93 ± 0.17 g/cm2, respectively; p < 0.001). Assuming a recessive model, carriers of the variant allele of the Ser242Gly polymorphism showed increased BMD values at the lumbar spine compare to wild-type subject (1.11 ± 0.35 and 0.92 ± 0.17 g/cm2, respectively; p = 0.0045). This is the first study demonstrating an association of non-synonymous polymorphisms in the P2RX4 and the risk of osteoporosis, suggesting a role of the P2X4R in the regulation of bone mass.
Electronic supplementary material
The online version of this article (doi:10.1007/s11302-012-9337-0) contains supplementary material, which is available to authorized users. 相似文献92.
93.
Chung-Che Chang Xiaobo Zhou Jesalyn J Taylor Wan-Ting Huang Xianwen Ren Federico Monzon Yongdong Feng Pulivarthi H Rao Xin-Yan Lu Facchetti Fabio Susan Hilsenbeck Chad J Creighton Elaine S Jaffe Ching-Ching Lau 《Journal of hematology & oncology》2009,2(1):1-6
Background
Cholestatic jaundice as a presenting symptom of Precursor T-lymphoblastic leukemia (T-ALL)/lymphoma (T-LBL) has never been reported in literature. Similarly, precursor T-ALL/T-LBL is characteristically negative for synaptophysin. We report the first case of a patient with precursor T-ALL/T-LBL who presented with cholestatic jaundice and aberrant tumor expression of synaptophysin.Case report
42 year old male presented with anorexia, nausea, jaundice, pale stools, dark urine and about 35 pound weight loss over the previous 3 weeks. The initial laboratory work was suggestive of cholestatic jaundice. Markedly elevated LDH (2025 U/L) and CA 19-9 (1778 u/ML) were also noticed. The CT scan of abdomen showed massive hepatomegaly with coarse echotexture with contracted gall bladder and normal sized common bile duct. Chest x-ray revealed a mediastinal mass with mediastinal widening. CT scan of the chest showed anterior mediastinal mass (16 cm × 10 cm). CT guided biopsy of the mass showed malignant lymphoma with diffuse proliferation of medium sized lymphoid cells. The neoplastic cells were positive for CD1a, CD3, CD4, CD5, CD8 and CD43 with aberrant expression of synaptophysin. PET CT scan again showed a large anterior mediastinal mass with diffuse liver involvement and abnormal activity in axial bones. CT guided liver biopsy and bone marrow biopsy revealed the same morphology and immunohistochemistry. Bone marrow aspirate showed 85% lymphoblasts. Thus, the diagnosis of precursor T-ALL/T-LBL was made and jaundice with elevated CA 19-9 were attributed to intrahepatic cholestasis.Conclusion
Our case illustrates an unusual presentation of hematological malignancies as cholestatic jaundice. It also indicates the non-specific nature of CA 19-9 for pancreaticobiliary malignancies. It is the first case report of neoplastic precursor T cell lymphoblasts with unusual expression of synaptophysin. Tissue biopsy with thorough immunohistochemistry is required to differentiate precursor T-ALL/T-LBL from thymoma and small cell carcinoma. 相似文献94.
95.
SB Lanzavecchia MI Remis JL Cladera RO Zandomeni 《Entomologia Experimentalis et Applicata》2010,136(1):53-65
DNA size polymorphisms were utilized in a study of 24 natural populations of Ceratitis capitata Wiedemann (Diptera: Tephritidae) from Argentina. The first intron of alcohol dehydrogenase 1 gene (Adh1) was amplified using exon priming intron crossing‐polymerase chain reaction. Three size variants were detected among the 307 samples analyzed. To better differentiate the size variants, further digestion of PCR products with the EcoRI restriction enzyme was carried out. Complete nucleotide sequences of the three‐allele variants were obtained and single changes, insertions, deletions, and EcoRI recognition sites were located. Population allele frequencies were analyzed and a global mean heterozygosity (He) of 0.33 was obtained. In most populations, observed allelic frequencies conformed to Hardy–Weinberg expectations. Significant differences between provinces and sampling sites within these provinces, and among some populations were found. The average number of insects exchanged among populations (Nm) was estimated and high values were observed between Argentina and populations from two African countries (Morocco and Kenya), Australia, and Hawaii (Kauai). Pest introduction sources and dispersion patterns in Argentina are discussed based on these results as well as on available bibliographical data. 相似文献
96.
97.
RNA polymerase II primes Polycomb‐repressed developmental genes throughout terminal neuronal differentiation
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98.
Park H Hilsenbeck JL Kim HJ Shuttleworth WA Park YH Evans JN Kang C 《Molecular microbiology》2004,51(4):963-971
The shikimate pathway synthesizes aromatic amino acids and other essential metabolites that are necessary for bacteria, plants and fungi to survive. This pathway is not present in vertebrates and therefore represents an attractive target for antibacterial agents. We have successfully crystallized and solved the structure of unliganded, inhibitor-liganded and tetrahedral intermediate (TI)-liganded forms of Streptococcus pneumoniae EPSP synthase. The overall topology of the S. pneumoniae EPSP synthase is similar to that of the Escherichia coli EPSP synthase. In addition, the majority of residues responsible for ligand binding were conserved between the two proteins. TI-liganded structure provides absolute configuration of the C-2 atom from the F-PEP moiety of the enzyme-bound intermediate and also defines key residues responsible for the enzyme reaction. Comparison of the unliganded state and substrate-bound state of the enzyme provides insights into the structural mechanisms involved in dynamic events of ligand binding, domain movement and closure. This structural study of the pathogenic bacteria S. pneumoniae EPSP synthase with inhibitor and TI will provide invaluable information for the design of new-generation antibiotics. 相似文献
99.
K?Zouaoui?BoudjeltiaEmail author Ph?Cauchie Cl?Remacle M?Guillaume D?Brohée JL?Hubert M?Vanhaeverbeek 《BMC biotechnology》2002,2(1):8
Background
Determination of clot lysis times on whole blood, diluted whole blood, plasma or plasma fraction has been used for many years to assess the overall activity of the fibrinolytic system. We designed a completely computerised semi-automatic 8-channel device for measurement and determination of fibrin clot lysis. The lysis time is evaluated by a mathematical analysis of the lysis curve and the results are expressed in minute (range: 5 to 9999). We have used this new device for Euglobulin Clot Lysis Time (ECLT) determination, which is the most common test used in laboratories to estimate plasma fibrinolytic capacity. 相似文献100.