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41.
The diagnosis of mucinous pancreatic lesions, which include mucinous noncystic adenocarcinoma, intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), and mucinous metaplasia, is critical, given different clinical management and prognosis. This retrospective study is done to assess the cytological features and pitfalls associated with these entities in cytological samples.A search for pancreatic cytology specimens with histological confirmation of the various pancreatic mucinous lesions was done from 1988 to 2005: 9 mucinous adenocarcinoma, 14 IPMN, 11 MCN, and 3 mucinous metaplasia. The majority (35/37) had been endoscopic ultrasound-guided fine-needle aspirations. The cellularity, background extracellular mucin, epithelial architecture, mucinous nature of the epithelium, cell shape, and nuclear features were evaluated on the cytology material. Of the 22 cytological features evaluated, the presence of three-dimensional clusters, micropapillary structures, and nuclear atypia, which includes nuclear crowding, increased N/C ratio, anisonucleosis, nuclear membrane contour irregularity, clumpy chromatin, and prominent nucleoli, was found to be consistently associated with mucinous adenocarcinoma. There were no statistically significant cytological features, which helped in differentiating IPMN, MCN, and mucinous metaplasia. There was a relatively high false-positive rate in the IPMN group (5/14, 36%). Review of the histological specimen showed severe dysplastic epithelial change in these cases. One false-positive case of mucinous metaplasia (1/3, 33%) showed marked intraepithelial acute inflammation.The cytological diagnosis of mucinous pancreatic lesions remains challenging, except for mucinous noncystic adenocarcinoma. The findings were largely nonspecific in the differentiation between IPMN, MCN, mucinous metaplasia, and incidentally sampled gastrointestinal epithelium. False-positive diagnosis of adenocarcinoma occurs not infrequently in the setting of IPMN with severe dysplastic epithelial change and in lesions with associated acute inflammation, and can be a pitfall in the diagnosis of these lesions.  相似文献   
42.
背景:随着内固定材料和内固定技术的发展,越来越多的国内外学者开始应用人工骨材料联合椎弓根钉内固定修复脊柱结核。目的:综述人工骨修复材料联合椎弓根内固定修复脊柱结核的特点。方法:应用计算机检索CNKI和PubMed数据库1985至2014年有关人工骨移植材料修复脊椎结核方面的文献,中文关键词为“脊椎结核、骨移植、内固定”,英文关键词为“Spinal tuberculosis,Bone graft,Fixation”。结果与结论:在骨修复材料联合椎弓根内固定修复脊柱结核中,自体骨是骨移植的金标准,无免疫排斥反应,但为了避免自体骨取骨量有限、取骨后疼痛等并发症的发生,人工骨材料得到了广泛研究。目前应用的人工骨材料主要包括钛及其合金、羟基磷灰石复合物及医用硫酸钙,具有良好的生物相容性,但均存在一定的局限性和不足。     中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程  相似文献   
43.
Aberrant expression of matrix metalloproteinase (MMP)-2 and tissue factor pathway inhibitor (TFPI)-2 not only correlate with tumorigenesis, but also with tumor invasion and metastasis. This study aims to investigate the correlation and prognostic significance of MMP-2 and TFPI-2 differential expression in pancreatic carcinoma. Immunohistochemistry was used to evaluate MMP-2 and TFPI-2 expression in tumor tissues and corresponding non-tumor tissues from 122 patients with pancreatic carcinoma. The results showed that the expression of MMP-2 was significantly (P < 0.05) higher in tumor tissues (78.7%) than in adjacent non-tumor tissues (27.9%), whereas the expression of TFPI-2 was significantly (P < 0.001) lower in tumor tissues (27.9%) than in adjacent non-tumor tissues (79.5%). Spearman’s rank correlation test showed a negative correlation between MMP-2 and TFPI-2 expression (r = -0.346, P < 0.001). Kaplan-Meier survival analysis showed that high MMP-2 expression was significantly correlated with decreased disease-free survival (DFS) (P < 0.001) and overall survival (OS) (P < 0.001), while high TFPI-2 expression was significantly associated with increased DFS (P < 0.001) and OS (P < 0.001) of the patients. Multivariate analysis showed that high MMP-2 expression can act as an independent predictive factor for poor DFS (P = 0.01); and low TFPI-2 expression as an independent prognostic factor for poor DFS (P < 0.001) and OS (P < 0.001). In conclusion, our findings suggested that the differential expression of MMP-2 and TFPI-2 have a negative correlation in pancreatic carcinoma tissues; they may be considered as valuable biomarkers for prognosis of pancreatic carcinoma.  相似文献   
44.
Objective: NF-κB signaling plays a central role in the regulation of inflammatory responses in atherosclerosis. R65 ribozyme gene suppresses activation of NF-κB pathway, therefore we studied whether R65 gene therapy can ameliorate oxidized low-density lipoprotein (ox-LDL) induced human umbilical vein endothelial cells (HUVECs) injury. Methods and results: Recombinant adeno-associated virus serotype 9 (rAVV9) vector was used to transfect the R65 ribozyme gene (rAVV9-R65) into HUVECs then following ox-LDL stimulation, expression of NF-κB p65 and p50 subunits, inflammatory mediators and cell apoptosis were examined. First, rAVV9-enhanced green fluorescent protein (eGFP)-R65 at 1×107 v.g./cell multiplicity of infection reached a long-lasting and significant increase in R65 gene expression. Second, ox-LDL treatment led to time- and dose-dependent activation of NF-κB pathway, and enhanced inflammatory response and cell death evidenced by increased expression of nuclear NF-κB p65 and p50 subunits, greater production of tumor necrosis factor α, interleukin-6 and von willebrand factor and 20.57% increasedapoptotic HUVECs. Third, over-expression ofR65 gene was 2-fold increased in HUVECs attenuated ox-LDL induced unclear accumulation and expression of p65 subunit and ameliorated inflammation and cell death (all P < 0.05). Conclusion: rAAV9-mediated R65 ribozyme gene transfection in cultured HUVECs effectively inhibits ox-LDL induced activation of NF-κB and production of inflammatory cytokines and prevents cell apoptosis.  相似文献   
45.
Aim: To investigate the expression of CCAAT enhancer binding protein-α (C/EBP-α) in normal human liver and liver fibrosis and its probable association with autophagy. Methods: Double label immunohistochemistry was used to detect the location of C/EBP-α in hepatocytes and hepatic stellate cells (HSCs). The expression of C/EBP-α, Atg5, and Atg6 was also evaluated by immunohistochemistry in paraffin sections of human liver. HSC-T6 cells were treated with rapamycin and 3-methyladenine (3MA) to induce or inhibit autophagy, and the expression of C/EBP-α protein was detected by Western blotting. Results: Double label immunohistochemistry showed that C/EBP-α was predominantly located in hepatocytes and that its expression was significantly decreased in fibrosis compared with normal liver. Atg5 expression was increased in fibrosis but was located primarily in liver septa and peri-vascular areas, which was consistent with the distribution of HSCs. In contrast, Atg6 was not expressed in normal or fibrotic liver. Treatment of HSC-T6 cells in culture with rapamycin or 3MA decreased or increased C/EBP-α expression, respectively, as shown by Western blotting. Conclusion: C/EBP-α was primarily expressed in hepatocytes in normal liver, but its expression decreased significantly in liver fibrosis. Autophagy might play a role in liver fibrosis through its association with C/EBP-α, but this hypothesis warrants further investigation.  相似文献   
46.
We conducted a case-control study to investigate the association between interleukin (IL)-10-592C/A, -819C/T and -1082A/G polymorphisms and susceptibility to diabetic nephropathy. A hospital-based case-control study was taken in our study. A total of 172 patients with proven type 2 diabetes mellitus and 344 controls were recruited from the First Affiliated Hospital of Xinxiang Medical University between March 2012 and October 2014. Genotyping of IL-10 -592C/A, -819C/T and -1082A/G polymorphisms was done by done by PCR-RFLP methods. By the χ2 test, the distributions of the GG, GA and AA genotypes in IL-10 -1082A/G were significantly different between patients with diabetic nephropathy and control subjects (χ2 = 8.09, P = 0.02). By conditional logistic regression analysis, we found that the AA genotype of IL-10 -1082A/G was associated with an elevated risk of diabetic nephropathy compared to the GG genotype in codominant model, and the adjusted OR (95% CI) was 2.38 (1.23-4.57). In dominant model, the GA+AA genotype was associated with a significantly increased risk of diabetic nephropathy compared to the GG genotype in dominant model (OR = 1.47, 95% CI = 1.05-2.16). In recessive model, the AA genotype could influence the susceptibility to diabetic nephropathy when compared with the GG+GA in recessive model (OR = 2.08, 95% CI = 1.12-3.85). In conclusion, we suggested that IL-10 -1082A/G gene polymorphism was correlated with development of diabetic nephropathy, but no association was observed between IL-10 -819T/C and -592A/C and risk of diabetic nephropathy.  相似文献   
47.
Objective: To determine the expression of NIMA-related kinase NEK2 and evaluate its clinical value in colon cancer. Method: Sixty specimens of colon cancer, 30 specimens of paracancerous colon tissues and 10 specimens of normal colon tissues conventionally resected in surgery at the Second Affiliated Hospital of Nantong University from February 2006 to February 2014 were collected. These tissues were detected for the expression of Nek2 using Western Blot and immunohistochemical staining. The relationship between Nek2 protein expression and the clinicopathology and prognosis of colon tissues was discussed. Results: The expression level and positive expression rate of Nek2 protein in the colon cancer were obviously higher than that in the paracancerous tissues and normal colon tissues. They were also significantly higher in the paracancerous tissues than in the normal tissues (P<0.05). Statistical analysis revealed that Nek2 protein expression was not obviously correlated with gender, age and tumor size, but obviously correlated with degree of differentiation (P=0.008), TNM staging (P=0.000), lymph node metastasis (P=0.022) and tumor invasion (P=0.011). With the plotting of Kaplan-Meier survival curve, it could be seen that Nek2 protein expression was not significantly correlated with survival (P=0.0048). High Nek2 protein expression may be an independent risk factor for colon cancer (HR=0.227, 95% CI 0.101-0.510). Conclusion: High Nek2 protein expression reflects the malignant behavior of colon cancer. Playing important roles in the occurrence of colon cancer, Nek2 protein expression has diagnostic and prognostic value in colon cancer.  相似文献   
48.
非细胞体系核重构过程的超微结构研究   总被引:3,自引:1,他引:3  
张博  翟中和 《解剖学报》1992,23(1):48-52
用电镜观察Lambda DNA与非洲爪蟾卵提取物在非细胞体系内的核重构,发现Lambda DNA首先诱导形成类染色质结构,膜泡、核孔复合体围绕这一结构组装成双层核膜,同时类染色质也随着核膜的装配,表现出从致密凝聚到呈现松散均匀分布的变化。有工作表明,在由染色质诱导的核重构过程中,或者是膜泡先与染色质结合,然后有核孔出现,或者是核孔物质先与染色质作用,膜泡通过结合核孔物质形成双层核膜。我们观察由外源DNA诱导的核重构过程,则发现膜泡与核孔复合体先分别独立地与类染色质结构相互作用,然后核孔复合体再镶嵌到双层核膜中。  相似文献   
49.
本研究选择奇异变形杆菌和绿肿杆菌等作为实验体系,从群体发生发展过程的宏观表现上探讨了生物控制的时空表达及非线性问题。结果表明,杆菌发生过程的时相周期性可以表现为空间的波形靶图样,并具有分形的特征。实验结果表明,菌群在生长过程中的代谢产物是富含生物信息的控制中介机制。我们认为,生物系统局部存在着准平衡和准封闭的微生态环境,生物液晶的存在和相变是细菌群体发生过程的重要协同中介因素。  相似文献   
50.
目的 探讨改良Ⅱ期法耳廓再造的方法并总结6年来的临床应用经验。方法 对146例(155耳)小耳畸形患者行耳廓再造术,手术分Ⅱ期进行。Ⅰ期:采用“U”形切口,切除残耳,在耳后分离合适的腔隙,置入肋软骨耳支架,耳垂向后转位衔接于再造的耳廓下方。6个月后行Ⅱ期手术:掀起耳廓,耳后置入软骨块,颞浅筋膜瓣转移覆盖后行中厚皮片移植术。结果 146例患者中141例(150耳)Ⅰ期术后恢复顺利,伤口愈合良好;5例(5耳)Ⅰ期术后4~6d出现皮瓣尖端坏死,范围约1.0 cm×1.5 cm,经换药后痊愈,未出现软骨外露、感染等;139例(147耳)Ⅱ期术后耳后移植皮片成活良好,7例(8耳)Ⅱ期术后出现耳后移植皮片部分成活不良,换药1周后愈合。146例患者随访94例(97耳),失访52例(58耳),随访时间为术后6个月至2年,随访病例均无感染、软骨吸收等并发症,再造耳廓结构清晰,耳颅角稳定。结论 改良Ⅱ期法耳廓再造手术操作相对简单,易于掌握,是耳廓再造的较为理想的方法之一。  相似文献   
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