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Neuronal growth regulator 1 (NEGR1), a member of the immunoglobulin superfamily cell adhesion molecule subgroup IgLON, has been involved in neuronal growth and connectivity. Genetic variants, in or near the NEGR1 locus, have been associated with obesity and, more recently, with learning difficulties, intellectual disability, and psychiatric disorders.Here, we described the only second report of NEGR1 gene disruption in 1p31.1 microdeletion in two patients. Patient 1 is a 14-year-old female with neurological and psychiatric features present also in her family. Patient 2 is a 5-month-old infant showing global hypotonia as unique neurological features till now. This patient also carries 7p22.1 duplication, of paternal origin, that could be responsible for some malformations present in the child.We hypothesize a role of NEGR1 in producing the phenotype of our patients and compare them with other cases previously reported in the literature and DECIPHER database to better identify a possible genotype-phenotype correlation.  相似文献   
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吴洋  宋燕妮 《现代肿瘤医学》2020,(18):3255-3259
乳腺癌是一类具有异质性的肿瘤,不同患者的治疗方法和疗效都不相同。尽管目前仍在努力为激素受体(hormone receptor,HR)阳性(+)、人表皮生长因子受体2(human epidermal growth factor receptor 2,HER-2)阴性(-)、淋巴结(axillary lymph node,ALN)阴性(-)的早期乳腺癌患者寻找合适的治疗方法,但其术后是否需要化疗仍然是肿瘤科医生面临的一个难题。以往治疗主要依赖于经典的组织病理学和免疫组织化学技术,随着精准医疗时代的到来,我们需要更定量的诊断方法和合理的个体化治疗。虽然化疗可降低疾病复发风险并提高生存率,但它带来的不良反应事件会降低患者的生活质量,尤其低复发风险(recurrence risk,RS)有可能超过化疗益处。21基因检测不仅可以预测这类早期乳腺癌化疗疗效及评估预后,还可提供精准的个体化治疗方案指导用药,为患者增添信心。本文就乳腺癌21基因检测的研究进展进行综述。  相似文献   
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Many cellular signaling pathways are involved in the development of cancer. Depending on the tumor entity, the nature as well as the mode of activation can differ. Some signaling pathways frequently show changes as all tumor cells have to fulfill some basic requirements such as independence from growth factors or insensitivity against apoptosis. In this review, the possibilities of a tumor to manipulate signaling pathways to reach these goals are exemplified based on an archetypical melanoma cell. In addition, new therapeutic options based on the knowledge of signaling pathways will be discussed.  相似文献   
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目的探讨p16基因突变在白血病发生中的作用及基因突变的机制。方法利用点突变检测仪、水平和垂直板电泳对p16基因的外显子1、外显子2的PCR扩增产物作缺失和点突变分析。结果在白血病35例临床标本中有22例发生缺失突变,6例发生点突变,突变率约80%。在22例缺失突变病例中,有10例为不完全缺失突变即有低于外显子509bp的扩增产物。结论p16基因含有“GC”DNA重复顺序,易发生DNA重组及易位和重排。在白血病发生中起重要作用  相似文献   
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What is the value of bcl-2 protein detection for histopathologists?   总被引:15,自引:0,他引:15  
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BACKGROUND: The responses of mice to the mite allergen Der p 1 have been used to study the mechanisms of allergic sensitization and the development of new types of immunotherapy. Many of the studies require a knowledge of the T cell epitopes, and because Der p 1 is polymorphic, the effect of natural amino acid substitution in the allergen. The intranasal administration of peptides containing T cell epitopes can induce a mucosal tolerance but it is not known if the major activity is limited to stimulatory peptides and if, as found for autoimmunity, some epitopes are not inhibitory. OBJECTIVE: To determine and compare the sequences of Der p 1 which contain stimulatory epitopes for the high responding H-2(b) and H-2(q) mice and the sequences which induce tolerance by intranasal administration of peptides. METHODS: T cell responses of mice immunized with Der p 1 were measured by in vitro T cell stimulation assays so an extensive study of epitope recognition and intranasal tolerance could be made. Synthetic peptides were used to examine the stimulatory and inhibitory ability of all Der p 1 sequences and to map the major H-2(b) epitope in detail. This included the effect of the common polymorphic amino acid 124 substitution found within this epitope. RESULTS: Three and two regions, respectively, were found to contain stimulatory T cell epitopes for H-2(b) and H-2(q) mice. The peptides in these regions were also the most active at inducing intranasal tolerance for the responding haplotype. The correspondence between inhibitory and stimulatory peptides was maintained for the fine mapping of the major H-2(b) epitope. This was found about a core region of 118-126 which was overlapping but separate to a consensus sequence for the binding of endogeneous peptides. Peptides with alanine at the naturally polymorphic residue 124 stimulated and inhibited responses to Der p 1 more effectively, while peptides with the valine 124 variant were immunogenic but poorly cross-reactive. CONCLUSIONS: The intranasal administration of peptides representing each of five epitopes recognized by two strains of mice were able to induce mucosal tolerance and the major tolerizing activity was limited to these epitopes. The position of the core major epitope for C57 mice, which differs from a previously predicted epitope, and its specificity for the natural alanine 124 variant is described.  相似文献   
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胃癌组织p16基因蛋白表达的意义   总被引:9,自引:4,他引:5  
目的 检测 p1 6基因蛋白在胃癌组织、癌旁组织中的表达及其分布特点 ,分析其与胃癌临床病理学特征及预后的关系 .方法 采用 S- P免疫组织化学法对 53例胃癌组织及 35例癌旁组织进行 p1 6蛋白的定位观察 .结果 各病理类型胃癌组织、癌旁组织均有 p1 6基因蛋白表达 .阳性率分别为 62 .3% (33/53)和 88.6% (31 /35) ,阳性细胞的棕黄色颗粒主要位于细胞核 .胃癌 p1 6基因蛋白表达与性别、年龄、肿瘤部位在统计学上无差异 (P>0 .0 5) ;而与组织学类型、病理分级、淋巴结转移、临床病理分期在统计学上有差异 (P<0 .0 5) .p1 6蛋白阳性者 5年生存率 51 .0 %高于 p1 6蛋白阴性者 2 0 .0 % (P<0 .0 5) .结论  p1 6基因缺失和表达水平的改变与胃癌发生、发展密切相关 ,检测 p1 6基因蛋白表达可作为辅助临床判断胃癌的生物学行为及推测预后的指标  相似文献   
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