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131.
为了探讨用Bullseye显示脑血流灌注显像数据的可能性,对8例典型脑梗塞病例及15例脑血流断层显像常规分析可疑病例的脑血流断层显像的横断面数据进行Bullscye显示,结果8例典型病人病灶用普通Bullseye即显示良好;常规分析可疑病例病变用普通Bullseye 8例显示良好,变黑Bullseye 13例显示出病灶;结果提示利用Bullseye显示脑血流灌注显像数据的可能。  相似文献   
132.
Deregulation of apoptosis is involved in prostate cancer development and progression. This study involved an immunohistochemical "profiling" of prostate tissue specimens from patients who underwent prostatectomy for localized prostate cancer, to identify apoptosis-specific alterations associated with premalignant precursor lesions. Prostate tissue was pathologically evaluated, and areas of benign acini, high-grade prostate intraepithelial neoplasia (HGPIN), and prostate cancer were identified. Immunohistochemical analysis was performed to determine the expression of p27Kip1, a key cell cycle regulator, transforming growth factor (TGF)-beta receptor II (TbetaRII), a critical signaling effector of TGF-beta; Smad4, a downstream intracellular effector of TGF-beta signaling; p53, a key apoptosis regulator; and prostate-specific antigen (PSA), a clinical marker of prostate cancer. The apoptotic index of the same cell populations was determined using the transferase-mediated digoxigenin-tagged 16-desoxy-uridine-triphosphate nick end labeling assay. Our findings indicate a significant reduction in p27Kip1 immunoreactivity in HGPIN (P<0.0001) and prostate cancer (P<0.0001) compared with the benign tissue. A significant down-regulation was detected in TbetaRII expression in HGPIN and prostate cancer compared with benign prostatic hyperplasia (BPH)(P<0.001). A significant decrease was also observed in Smad4 levels in HGPIN and prostate cancer compared with BPH (P<0.001). Evaluation of the incidence of apoptosis revealed a significant decrease in the apoptotic index among the epithelial cell populations in HGPIN and a further decrease in prostate carcinoma (P<0.01). This reduced apoptotic index correlated with a significant increase in p53 immunoreactivity in the prostatic carcinoma foci. Prostate cancer cells exhibited strong nuclear staining for p53 compared with adjacent HGPIN (P<0.05) and the benign lesions of the same prostate specimens (P<0.05). A significant reduction in PSA immunostaining was detected in HGPIN and prostate carcinoma foci compared with the benign glandular epithelia (P<0.001). These results further define deregulation of TGF-beta signaling effectors as a molecular basis for loss of apoptotic control contributing to the development of prostate tumors. Identification of apoptotic regulators in precursor premalignant lesions may have prognostic significance in disease progression as well as therapeutic value for targeting prostate cancer.  相似文献   
133.
Human adenocarcinoma (AC) is the most frequently diagnosed human lung cancer, and its absolute incidence is increasing dramatically. Compared to human lung AC, the A/J mouse-urethane model exhibits similar histological appearance and molecular changes. We examined the gene expression profiles of human and murine lung tissues (normal or AC) and compared the two species' datasets after aligning approximately 7500 orthologous genes. A list of 409 gene classifiers (P value <0.0001), common to both species (joint classifiers), showed significant, positive correlation in expression levels between the two species. A number of previously reported expression changes were recapitulated in both species, such as changes in glycolytic enzymes and cell-cycle proteins. Unexpectedly, joint classifiers in angiogenesis were uniformly down-regulated in tumor tissues. The eicosanoid pathway enzymes prostacyclin synthase (PGIS) and inducible prostaglandin E(2) synthase (PGES) were joint classifiers that showed opposite effects in lung AC (PGIS down-regulated; PGES up-regulated). Finally, tissue microarrays identified the same protein expression pattern for PGIS and PGES in 108 different non-small cell lung cancer biopsies, and the detection of PGIS had statistically significant prognostic value in patient survival. Thus, the A/J mouse-urethane model reflects significant molecular details of human lung AC, and comparison of changes in orthologous gene expression may provide novel insights into lung carcinogenesis.  相似文献   
134.
背景:随着疾病治疗模式的改变,人们已经意识到中医药在激素性股骨头坏死治疗过程中的重要性,因此利用生物信息学从分子水平分析激素性股骨头坏死的发病机制,构建疾病风险模型,并预测具有潜在治疗作用的中药,为后期中医药治疗激素性股骨头坏死提供一定的理论依据。目的:基于生物信息学挖掘激素性股骨头坏死的竞争性内源RNA(ceRNA)调控网络,分析其在激素性股骨头坏死中的分子调控机制,预测相关疾病靶点并构建疾病风险模型,同时预测具有潜在治疗作用的中药。方法:检索GEO数据库,下载激素性股骨头坏死的矩阵文件GSE123568和基因注释文件GPL15207。借助R语言等软件分析得到差异表达的长链非编码RNA与mRNA,并通过公共数据库预测与差异表达长链非编码RNA关联的miRNA-mRNA,再将预测到的mRNA与差异表达mRNA取交集,整合得到ceRNA网络。随后采用STRING数据库和Cytoscape软件筛选关键基因,利用R语言分析关键基因的功能与相关通路,并挖掘关键ceRNA网络。最后根据关键基因构建激素性股骨头坏死的风险模型,并进行中药预测。结果与结论:(1)与健康对照相比,激素性股骨头坏死患者共有7个长链非编码RNA和1763个mRNAs存在差异表达;(2)筛选出STAT3、KAT2B、AGO4、JAK2、JAK1、PTGS2共6个关键基因;(3)关键基因所富集的功能包括对肽激素的反应、白细胞介素6介导的信号通路、细胞对白细胞介素6的反应等生物学过程,涉及JAK-STAT、脂肪细胞因子、催乳素等信号通路;(4)4种mi RNAs(mi R-135a-5p、mi R-137、mi R-17-5p、miR-20b-5p)和2种长链非编码RNA(SNHG11、C20orf197)可能在导致激素性股骨头坏死发生发展过程中发挥关键作用;(5)KAT2B最有可能是激素性股骨头坏死发生发展的风险因子;(6)郁金、淫羊藿、黄芪具备治疗激素性股骨头坏死疾病靶点的可能。通过对激素性股骨头坏死相关长链非编码RNA介导的ceRNA网络进行分析,识别出潜在的疾病靶点、信号通路及潜在治疗中药,为进一步阐明其发病机制,并为后续的实验研究提供参考依据。  相似文献   
135.
Nasopharyngeal carcinoma (NPC) is a tumor derived from epithelial cells and Epstein-Barr virus infection has been reported to be a cause of this disease. Chemokine receptor CXCR4 was found to be involved in HIV infection and was highly expressed in human malignant breast tumors and the ligand for CXCR4, CXCL12 (SDF-1), exhibited high expression in organs in which breast cancer metastases are often found. The metastatic pattern of NPC is quite similar to that of malignant breast tumors. In this study, we investigated the expression of CXCR4 in nasopharyngeal carcinoma (NPC) tissues by immunohistostaining. We found different staining patterns, which included localization in the nucleus, membrane, cytoplasm or a combination of them. The staining intensity was also variable among samples. The metastatic rates in patients with high compared to low or absent expression was 38.6% versus 19.8%, respectively (P = 0.004). High expression of CXCR4 was associated with poor overall survival (OS = 67.05% versus 82.08%, P = 0.0225). These results suggest that CXCR4 may be involved in the progression of NPC and that a high level of CXCR4 expression could be used as a prognostic factor.  相似文献   
136.
目的 构建小鼠甲胎蛋白(α-Fetoprotein,AFP)与结核杆菌热休克蛋白70(Mycobacterium tuberculosis heat shock protein 70,Mt.HSP70)基因融合载体.并研究其在真核细胞中的表达情况。方法 以pcDNA3.1为基本单位构建AFP及HSP70的融合表达载体,融合基因以G-S-G-G-S连接子连接;用脂质体将系列载体导入COS-7细胞.48h后以免疫化学方法检测其表达。结果 构建的AFP和HSP70的单独及融合表达载体导入COS-7细胞48h后经RT-PCR检测可扩增出相应片段,细胞免疫化学染色为阳性。结论 AFP和HSP70的单独及融合表达载体构建成功,并能在真核细胞中表达。  相似文献   
137.
Our previous studies in mice showed that the nonmyeloablative conditioning regimen of fractionated irradiation of the lymphoid tissues (total lymphoid irradiation; TLI) and depletive anti-T-cell antibodies (anti-thymocyte serum) markedly increased the percentage of regulatory DX5+ and natural killer 1.1+ T cells in the mouse spleen, and prevented acute lethal graft-versus-host disease (GVHD) in BALB/c mice (H-2(d)) following the transplantation of bone marrow (BM) and peripheral blood mononuclear cells (PBMC) from C57BL/6 (H-2(b)) donors. The object of the current study was to determine whether the TLI and anti-thymocyte serum regimen protected natural killer T-cell deficient CD1(-/-) BALB/c mice against GVHD after BM and PBMC transplantation from C57BL/6 donors, and whether a similar conditioning regimen of TLI and anti-thymocyte globulin (ATG) can prevent GVHD in Lewis rat (RT1(l)) hosts after BM and PBMC transplantation from ACI rat (RT1(a)) donors. The experimental results in mice showed that, although wild-type BALB/c hosts are protected in association with a marked increase in CD1- reactive T cells expressing the invariant TCR identified with a CD1 tetramer reagent; CD1(-/-) BALB/c hosts are not. Studies of chimeric donor cells in mice protected from GVHD showed donor T-cell polarization to a Th2 cytokine pattern. Results in rats showed that approximately 1000 fold more donor PBMC cells were required to induce a similar incidence of lethal GVHD in TLI and ATG conditioned hosts as compared with hosts conditioned with single-dose total-body irradiation or total-body irradiation and ATG. Surviving TLI and ATG conditioned rat hosts were complete chimeras. In conclusion, the TLI and ATG/anti-thymocyte serum conditioning regimen protects against GVHD in rats and mice, and regulatory natural killer T cells are required for protection.  相似文献   
138.
Serotype distribution and antibiotic resistance (AR) among group B streptococci (GBS) affect GBS disease prevention strategies, but vary among patient groups. A multiplex PCR-based reverse line blot (mPCR/RLB) hybridisation assay was used to compare the distributions of GBS serotypes, serotype III subtypes and AR-associated genes among 666 invasive isolates from 663 patients, divided into five age groups: infants, early-onset (EO; 0-6 days) and late-onset (LO; 7-90 days); children (aged 3 months to 14 years); women of childbearing age (WCBA; aged 15-45 years); and other adults (males aged >15 years; females aged >45 years). Serotypes Ia and V and serosubtype III-1 accounted for 60% of infections. Serosubtype III-2, which corresponds to a virulent clone belonging to sequence type (ST)17, was relatively uncommon overall (7%), but was associated strongly with LO infant infections, in which it was significantly more common than in adult infections (25/104 (24%) vs. 9/392 (2%), p <0.0001) or in EO infections (25/104 (24%) vs. 14/155 (9%), p <0.005). Erythromycin resistance genes were found in 8% of all isolates (ermB 3%, ermA 2.5% and mefA/E 2%), in 11-15% of isolates of serotypes II and V and subtype III-1, but in none of the isolates of serosubtype III-2 (III-2, 0/49 vs. all others, 54/618 (9%), p <0.04). In summary, the virulent serosubtype III-2 was associated strongly with LO infant GBS infection, but was less likely than other serotypes or serosubtype III-1 to carry AR genes.  相似文献   
139.
The D3 dopamine receptor gene is an important candidate gene for schizophrenia, since (because of its almost exclusive expression in the limbic system) it combines the dopamine receptor hypothesis with the limbic system hypothesis of schizophrenia. A BalI restriction fragment length polymorphism of the D3 dopamine receptor gene has been typed in 107 schizophrenic patients and 98 normal controls from Sichuan (China). With regard to alleles or genotypes, no significant differences were obtained between controls from Europe and China, between patients and controls, and between patient subgroups and controls. These results indicate a lack of association between schizophrenia and the D3 dopamine receptor gene in our sample. Our findings are at variance with reports of a significant excess of homozygosity at the D3 dopamine receptor gene in schizophrenic patients from Wales (United Kingdom) and Alsace (France). In conclusion, further studies will be needed with larger samples of patients from Wales and Alsace as well as with samples of different racial groups to prove or disprove the initial positive association between schizophrenia and genotypes of the D3 dopamine receptor gene. © 1993 Wiley-Liss, Inc.  相似文献   
140.
P-gp、GSTπ及TopoⅡ在胃癌中的表达及临床意义   总被引:13,自引:0,他引:13  
目的:探讨耐药基因蛋白P-gp、GSTл和TopoⅡ在胃癌中的表达及其临床意义。方法:应用S-P免疫组化法对85例胃癌进行检测。结果:胃癌组织P-gp、GSTл表达率分别为37.65%及63.53%,表达强度与临床分期有关,其中高分期者P-gp表达较低分期者为高。TopoⅡ表达率为55.29%,阳性率与组织学分类相关,分化较低者(59.57%)较分化较高者(38.30%)阳性率高。结论:P-gp、GSTл、TopoⅡ的耐药机制各不相同,根据P-gp、GSTл和TopoⅡ表达情况进行耐药物选择对办癌化疗具有重要的指导意义。  相似文献   
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