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The critical role of major histocompatibility complex (MHC) gene products in T cell activation was appreciated and extensively studied well before the availability of monoclonal T cell populations. However, the availability of cloned T cells has dramatically enhanced the ability to characterize the nature of MHC-restricted recognition by T cells. In certain areas, the use of monoclonal T cells has allowed substantial extension of principles already established through the use of heterogeneous T cells. In other cases, studies employing T cell clones have led to findings which were inaccessible to approaches using only heterogeneous T cell populations. On balance, it should also be pointed out that a significant number of critical questions concerning the MHC-restricted T cell repertoire remain best approached by studying the development of interactions of functionally heterogeneous T cell populations. The present review will focus upon recent progress in several areas in which the use of cloned T cells has been particularly important in characterizing the nature of MHC-restricted recognition. In particular, the restriction of T cell recognition by class II MHC products (Ia) is examined in detail.  相似文献   
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脾虚是桥本氏甲状腺炎发生的根本原因,因脾虚所生之痰、瘀不仅是桥本氏甲状腺炎病程中的病理产物,也是导致桥本氏甲状腺炎伴发症状最重要的病理因素,伴随着疾病的发生发展。从脾的病理生理,桥本氏甲状腺炎的病变发展,脾虚与免疫及桥本氏甲状腺炎的关系以及应用益气化痰活血法治疗进行论述,提出从脾论治桥本氏甲状腺炎及其并发症,以期为桥本氏甲状腺炎及其并发症的中医药治疗提供参考。  相似文献   
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Purpose

Previous studies have found that some immune-related genes were associated with autoimmune thyroid diseases (AITDs). A couple of studies have explored the association between vitamin D (1,25-dihydroxyvitamin D3) receptor (VDR) gene polymorphisms and susceptibility to AITDs in different populations and found conflicting results. This case-control study was designed to evaluate the role of polymorphisms of VDR gene in the predisposition of AITDs in a Chinese Han population.

Methods

A total of 417 patients with Graves’ disease (GD), 250 patients with Hashimoto's thyroiditis (HT) and 301 healthy subjects were enrolled. The Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometer (MALDI-TOF-MS) Platform was applied to detect four SNPs (rs1544410, rs2228570, rs731236 and rs7975232) in the VDR gene.

Results

In the rs7975232 allele A frequency showed a significant increase in GD patients (30.34% vs. 25.42% in controls; P = 0.041, OR = 1.278, 95%CI = 1.010–1.617). However, no relationship was found between clinical phenotypes and the four SNPs.

Conclusions

This result suggests that the VDR gene may be one susceptibility gene which contributes to the risk of GD.  相似文献   
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Riedel thyroiditis is a rare fibrosing disorder characterized by extension of the fibroinflammatory process beyond the thyroid capsule. Due to the nature of this lesion, fine‐needle aspiration often yields scant material and may be interpreted as non‐diagnostic. In this report, we describe cytologic features that allow the cytopathologist to favor a diagnosis of Riedel thyroiditis, thereby guiding appropriate further work‐up and management. Diagn. Cytopathol. 2015;43:747–750. © 2015 Wiley Periodicals, Inc.  相似文献   
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Primary mediastinal large B-cell lymphoma is a subtype of diffuse large B-cell lymphoma, arising in the mediastinum from putative thymic B-cell origin with distinctive clinical and genetic features. Generally, primary mediastinal large B-cell lymphoma is believed as only deriving in the mediastinum. The current study presents a rare case of primary mediastinal large B-cell lymphoma which arising from thyroid in a renal recipient with Hashimoto’s thyroiditis. Moreover, we devoted a discussion to the relationship among primary mediastinal large B-cell lymphoma, immunomodulatory therapy and autoimmune diseases. The immunologic derangement induced by long-term immunomodulatory therapy and Hashimoto’s thyroiditis may be the possible cause for the ectopic lymphoma.  相似文献   
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