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目的:提高腹膜后椎前副神经节瘤的CT诊断水平.方法:报道3例经手术病理证实的腹膜后椎前副神经节瘤的临床资料、CT表现、病理结果并复习相关文献.结果:3例患者均位于腹膜后椎前、腹主动脉右侧、右侧肾上腺前内方.动脉期病灶实性部分呈中等程度不均匀强化;门脉期强化更广、更均匀;延迟期病灶强化程度开始减低;坏死区不强化,于门脉期边界显示最清.2例患者手术完全切除.1例部分切除,随访一年患者基本情况良好.结论:CT检查尤其是双期扫描并结合临床可提高诊断率,并为手术提供相关资料.  相似文献   
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Introduction

Amplification of the ESR1 gene, coding for estrogen receptor alpha, was shown to predict responsiveness to tamoxifen, however its prognostic impact in breast cancer patients has not been thoroughly investigated. Other factors that could contribute to responsiveness to tamoxifen treatment are polymorphisms in ESR1 gene and genes involved in tamoxifen metabolism.The aim of this study was to assess the prognostic role of ESR1 gene dosage in a consecutive group of breast cancer patients and to correlate this feature with clinico-pathological factors. Additionally, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphisms were analyzed in the tamoxifen-treated subgroup of patients.

Materials and Methods

Primary tumor samples from 281 stage I-III consecutive breast cancer patients were analyzed for ESR1 gene dosage using real-time PCR with locked nucleic acids hydrolysis probes. In the tamoxifen-treated subgroup of patients, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphism in leukocytes genomic DNA were analyzed. Results were correlated with clinico-pathological factors and with disease-free survival (DFS) and overall survival (OS).

Results

ESR1 amplification (with a cut-off level of 2.0) was found in 12% of the entire group of breast cancer patients, and in 18% of the ER-negative subgroup. This feature was associated with decreased DFS both in the entire group (P=0.007) and in the ER-negative subgroup (P=0.03), but not in the tamoxifen-treated patients.Patients with ESR1 PvuII wt/wt genotype and at least one UGT2B15 wt allele had a worse DFS (P=0.03) and showed a trend towards decreased Os (P=0.08) in comparison to patients with ESR1 PvuII wt/vt or vt/vt genotype and UGT2B15 *2/*2 genotype.

Conclusions

ESR1 amplification can occur in ER-negative tumors and may carry poor prognosis. In the tamoxifen-treated subgroup, poor prognosis was related to the combined presence of ESR1 PvuII wt/wt and UGT2B15wt/wt or wt/*2 genotype.  相似文献   
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Heat shock factors (HSFs) in plants regulate heat stress response by mediating expression of a set of heat shock protein (HSP) genes. In the present study, we isolated a novel heat shock gene, TaHSF3, encoding a protein of 315 amino acids in wheat. Phylogenetic analysis showed that TaHSF3 belonged to HSF class B2. Subcellular localization analysis indicated that TaHSF3 localized in nuclei. TaHSF3 was highly expressed in wheat spikes and showed intermediate expression levels in roots, stems, and leaves under normal conditions. It was highly upregulated in wheat seedlings by heat and cold and to a lesser extent by drought and NaCl and ABA treatments. Overexpression of TaHSF3 in Arabidopsis enhanced tolerance to extreme temperatures. Frequency of survival of three TaHSF3 transgenic Arabidopsis lines was 75–91 % after heat treatment and 85–95 % after freezing treatment compared to 25 and 10 %, respectively, in wild-type plants (WT). Leaf chlorophyll contents of the transformants were higher (0.52–0.67 mg/g) than WT (0.35 mg/g) after heat treatment, and the relative electrical conductivities of the transformants after freezing treatment were lower (from 17.56 to 18.6 %) than those of WT (37.5 %). The TaHSF3 gene from wheat therefore confers tolerance to extreme temperatures in transgenic Arabidopsis by activating HSPs, such as HSP70.  相似文献   
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病程相关(PR)蛋白质经常被用作抗病反应的分子标记。利用免疫印迹(WB)技术检测了7个PR1家族蛋白质在水稻(Oryza sativa)叶片生长及与白叶枯病菌互作反应过程中的表达,发现6个PR1家族蛋白质在叶片生长中有表达。检测PR1蛋白质在Xa21介导的抗白叶枯病过程中的表达,结果显示PR1#052、PR1#072、PR1#073和PR1#121四个蛋白质在抗病反应后期呈上调或诱导表达,PR1#071则表达下调。进一步比较它们在抗病、感病和对照(Mock)反应中的表达丰度,发现在抗病和感病反应中的变化幅度均明显大于对照反应,推测这些PR蛋白质在水稻-白叶枯病菌互作反应中发挥作用。另外,对PR1基因上游启动子区的cis元件进行了分析。该研究初步揭示了水稻PR1家族蛋白质的表达谱,为进一步了解PR1蛋白质的功能提供了线索。  相似文献   
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目的:通过对动物模型的制作模拟新生儿围产期缺氧缺血性脑损伤,研究其脑组织病理变化,为新生儿缺氧缺血性脑损伤的病理生理的研究以及进一步有效的治疗提供实验基础。方法:将40只7d新生昆明小鼠分四组,分别为正常组(A组)、单侧颈总动脉结扎组(B组)、单侧颈总动脉结扎+缺氧组(C组)和双侧颈总动脉结扎组(D组)。单侧颈总动脉结扎组(B组)行右侧颈总动脉结扎;单侧颈总动脉结扎+缺氧组(C组)行右侧颈总动脉结扎后将其置于20℃的恒温50mL密闭容器中,分不同的时间将其取出;双侧颈总动脉结扎组(D组)行双侧颈总动脉结扎,各组术后均送回母鼠身边继续母乳喂养,三天后再作病理检测。结果:行单侧颈总动脉结扎加缺氧60min时,小鼠结扎侧皮质及海马区出现病理改变,随着缺氧时间延长(90rain、100min、120min)病变范围逐渐扩大,病理改变越明显。结论:本实验显示单侧颈总动脉结扎同时缺氧一定时间可以导致小鼠脑组织损伤,脑细胞发生病理改变,且皮层及海马区域的神经细胞对缺氧缺血最为敏感,从而为进一步研究新生儿缺氧缺血性脑损伤提供了较为可靠的模型。  相似文献   
9.

Background

Serum γ - glutamyltransferase (GGT) is implicated in the pathogenesis of endothelial dysfunction and atherosclerosis. Albuminuria is a marker of endothelial damage and correlated with structural and functional integrity of the vasculature. Our objective was to evaluate the association between serum GGT level and prevalence of albuminuria in a Chinese population.

Materials and Methods

We conducted a population-based cross-sectional study in 9,702 subjects aged 40 years or older. Increased urinary albumin excretion was defined according to the urinary albumin-to-creatinine ratio (ACR) ranges greater or equal than 30 mg/g. Low-grade albuminuria was defined according to the highest quartile of ACR in participants without increased urinary albumin excretion.

Results

The prevalence of low-grade albuminuria and increased urinary albumin excretion were respectively 23.4% and 6.6% in this population and gradually increased across the sex-specific serum GGT quartiles (all P for trend <0.05). In logistic regression analysis, compared with subjects in the lowest quartile of serum GGT level, the adjusted odds ratios (ORs) in the highest quartile was 1.22 [95% confidence interval (CI), 1.04–1.43] for low-grade albuminuria and 1.55 (95% CI, 1.18–2.04) for increased urinary albumin excretion. In subgroup analysis, significant relationship of serum GGT level with both low-grade albuminuria and increased urinary albumin excretion were detected in women, younger subjects, overweight subjects and in those with hypertension or glomerular filtration rate greater than 90 (all P <0.05).

Conclusion

Serum GGT level is associated with urinary albumin excretion in middle-aged and elderly Chinese.  相似文献   
10.
Morgue is a unique multi-domain protein that contains a zinc finger motif, an F box, and a variant E2 conjugase domain. The presence of these domains suggests potentially complex and novel functions for Morgue in ubiquitination pathways. Morgue was originally identified via its gain-of-function enhancement of eye cell death phenotypes in Drosophila and ectopic expression of Morgue also influences circadian rhythms. However, there is as yet little known about Morgues normal developmental or physiological functions. To address this issue, we generated several morgue loss-of-function mutants via P element excision mutagenesis and analyzed the mutant phenotypes during the fly life cycle. These studies revealed that morgue null mutants are viable, though approximately 10% of the mutants exhibit defects in pupal spiracle eversion and malformations in the adult abdominal cuticle. In addition, a similar subset of morgue mutant embryos exhibited alterations in the normal number, position, or morphology of specific neurons and glia. Analysis of Morgue protein localization was addressed through generation of a transgenic fly strain that expresses a GFP::Morgue fusion protein. Use of this strain revealed Morgue protein localization in multiple cellular compartments, including nuclei, cytoplasm and membranes. Taken together, these diverse phenotypes and distribution patterns suggest pleiotropic functions for Morgue.  相似文献   
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