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排序方式: 共有937条查询结果,搜索用时 31 毫秒
31.
N. Sotnikova D. Voronin Y. Antsiferova E. Bukina 《Scandinavian journal of immunology》2014,80(3):198-208
The immunological paradox of pregnancy, when maternal immune system recognizes but does not reject the semiallogenic foetus, is not yet fully understood. The aim of this work was to detail the mechanisms of the interaction of decidual CD56+ NK, infiltrating the maternal part of placenta, and trophoblast cells of foetal origin. Samples of the endometrial tissue from 13 healthy non‐pregnant women, 37 placentas, obtained after medical abortion of viable pregnancy at 7–10 weeks of gestation, and 26 samples of placentas from first‐trimester recurrent spontaneous abortion (RSA) were used as the material for investigation. Phenotype of NK was assessed by flow cytometry. The influence of trophoblast cells upon IFNγ and GrB mRNAs expression by dNK was investigated by RT‐PCR. The influence of dNK upon trophoblast cells migration and invasion was studied using collagen and Matrigel systems. In RSA group comparing to the normal pregnancy, the decrease of dNK with inhibitory receptors (NKG2A) and elevation of activated dNK were seen. In normal pregnancy, but not in RSA, trophoblast cells increased the expression of IFNγ and GrB mRNAs by CD56+ dNK. Both in normal and RSA pregnancy, dNK inhibited the migration and invasion of trophoblast cells. Initially, low invasive and migration capacities of trophoblast cells were seen during RSA. Thus, unbalanced activation of dNK can lead to the impairment of dNK and trophoblast cells interaction during RSA. 相似文献
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p16INK4A and p15INK4B gene deletions in primary leukemias 总被引:4,自引:0,他引:4
Haidar MA; Cao XB; Manshouri T; Chan LL; Glassman A; Kantarjian HM; Keating MJ; Beran MS; Albitar M 《Blood》1995,86(1):311-315
The 9p21 locus has been deleted at a high frequency in a wide variety of tumors. Recently, two genes, p16INK4A and p15INK4B (also called MTS1 and MTS2), have been localized in close proximity at the 9p21 locus, encoding cyclin-dependent kinases 4/6 inhibitors of relative molecular mass 16 kD and 15 kD, respectively and also found to be deleted at a high frequency in tumor cell lines. We analyzed p16INK4A and p15INK4B genes in 178 cases of primary leukemias including 81 cases of chronic lymphocytic leukemia (CLL), seven of hairy cell leukemia (HCL), seven of chronic myelogenous leukemia (CML), 43 of acute myelogenous leukemia (AML), 27 of acute lymphoblastic leukemia (ALL), and 13 of myelodysplastic syndrome (MDS) by Southern blot analyses. The ALL cases showed a relatively high frequency of homozygous deletions (22%, 6 of 27) at the p16INK4A gene locus. Interestingly, of the six cases with p16INK4A homozygous deletions, only three showed homozygous deletions at the p15INK4B gene. In 81 CLL patients, we detected one homozygous and five heterozygous deletions at both the p16INK4A and p15INK4B genes and two heterozygous deletions at the p16INK4A gene alone. Deletion of these two genes in AML cases is relatively low (9%). We did not detect deletions in any of the MDS, HCL, and CML cases examined. Sequence analyses of p16INK4A gene of six CLL cases with heterozygous deletion at this locus showed a 27-bp deletion at the splice acceptor site of intron 1 in one case and changes in the coding sequence in three other cases. The data presented in this report showed that (1) p16INK4A and p15INK4B genes are preferentially deleted homozygously in ALL and heterozygously in CLL cases with frequent mutation in the second allele, and (2) p16INK4A gene appears to be more frequently deleted than p15INK4B gene. 相似文献
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LL Patton V Ramirez‐Amador G Anaya‐Saavedra W Nittayananta M Carrozzo K Ranganathan 《Oral diseases》2013,19(6):533-550
Human immunodeficiency virus‐related oral lesions (HIV‐OLs), such as oral candidiasis (OC) and oral hairy leukoplakia (OHL), have been recognized as indicators of immune suppression since the beginning of the global HIV epidemic. The diagnosis and management of HIV disease and spectrum of opportunistic infection has changed over the past 30 years as our understanding of the infection has evolved. We investigated the following controversial topics: (i) Are oral manifestations of HIV still relevant after the introduction of highly active antiretroviral therapy (HAART)? (ii) Can we nowadays still diagnose HIV infection through oral lesions? (iii) Is the actual classification of oral manifestations of HIV adequate or does it need to be reviewed and updated? (iv) Is there any novelty in the treatment of oral manifestations of HIV infection? Results from extensive literature review suggested the following: (i) While HAART has resulted in significant reductions in HIV‐OLs, many are still seen in patients with HIV infection, with OC remaining the most common lesion. While the relationship between oral warts and the immune reconstitution inflammatory syndrome is less clear, the malignant potential of oral human papillomavirus infection is gaining increasing attention. (ii) Effective antiretroviral therapy has transformed HIV from a fatal illness to a chronic manageable condition and as a result expanded screening policies for HIV are being advocated both in developed and in developing countries. Affordable, reliable, and easy‐to‐use diagnostic techniques have been recently introduced likely restricting the importance of HIV‐OLs in diagnosis. (iii) The 1993 EC‐Clearinghouse classification of HIV‐OLs is still globally used despite controversy on the relevance of periodontal diseases today. HIV‐OL case definitions were updated in 2009 to facilitate the accuracy of HIV‐OL diagnoses by non‐dental healthcare workers in large‐scale epidemiologic studies and clinical trials. (iv) Research over the last 6 years on novel modalities for the treatment of HIV‐OLs has been reported for OC and OHL. 相似文献
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Dr. P.M. Lissel LL.M 《Notfall & Rettungsmedizin》2013,16(5):389-392