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51.
We report a case of successful fused CT-sonographic imaging-guided percutaneous biopsy of an anterior mediastinal mass, which was visualized poorly with conventional sonography. Real-time sonography fused with CT can be useful for biopsy of anterior mediastinal masses that are not well visualized on conventional sonography.  相似文献   
52.
目的观察后牙金铂合金全金属颈环烤瓷熔附金属全冠(PFM)边缘适合性以及对牙龈健康的影响。方法对134颗后牙烤瓷熔附金属全冠(单冠或桥的基牙)修复2年后观察其边缘适合性以及牙龈健康状况的临床情况。结果后牙金铂合金全金属颈环PFM的边缘适合性以及牙龈健康状况均好。结论后牙金铂合金全金属颈环烤瓷熔附金属全冠(PFM)是一种好的设计,建议作为临床常规设计。  相似文献   
53.
目的:高效表达HCV CE2融合蛋白并进行初步应用. 方法:将2a型HCV全长CE2基因的cDNA重组于质粒pBacPAK8,构建重组转移载体pBacPAK-CE2,与经线性化修饰的家蚕核型多角体病毒(BmNPV)DNA共转染家蚕培养细胞株,构建重组病毒. 双酶切及PCR鉴定重组病毒基因组中目的片段的表达. 重组病毒感染BmN细胞株及五龄家蚕幼虫后,SDS-PAGE分析细胞培养上清、细胞抽提物及幼虫体液样品中,HCV CE2融合蛋白的特异性条带. 并用间接ELISA法初步检测表达产物的生物活性. 结果:双酶切及PCR鉴定重组病毒基因组含有约1.6 kb的目的片段,重组病毒感染后的BmN细胞培养上清、细胞抽提物及幼虫体液样品中,均可见一Mr约90×103的特异性条带;用间接ELISA检测证明表达产物具有较好的免疫原性. 结论:HCV CE2融合基因在家蚕培养细胞及蚕幼虫中获得了高效表达,并具有生物活性,为进一步进行疫苗的研究及临床诊断试剂的开发奠定基础.  相似文献   
54.
Antibodies capable of recognizing key molecular targets isolated e.g. by phage display technology have been used in the pursuit of new and improved therapies for prevalent human diseases. These approaches often take advantage of non-immunogenic antibody fragments to achieve specific toxin-, radioactivity- or effector-domain delivery. There is now a growing interest in using anti-idiotypic antibodies or other antigen mimics to induce potent immune responses against antigen structures in question. We have earlier reported on the functional rescue of antibodies that are active when fused to the phage, but inactive as soluble protein [Jensen, K.B., Larsen, M., Pedersen, J.S., Christensen, P.A., Alvarez-Vallina, L., Goletz, S., Clark, B.F. and Kristensen, P. (2002) Functional improvement of antibody fragments using a novel phage coat protein III fusion system. Biochem. Biophys. Res. Commun. 298, 566-73.]. The rescue was accomplished by maintaining the fusion between the antibody fragment and portions of the filamentous bacteriophage coat protein 3, as present in the original antibody-displaying phage. In the present study, we have applied this system in an attempt to improve immunogenicity of anti-idiotypic antibodies isolated by phage display. Here we demonstrate that by preserving linkage between phage antibody and the N-terminal domain of phage coat protein 3, we induce multimerization of the antibody fragments, and improve their immunogenicity. This immunization approach allows induction of anti-idiotypic antibodies in mice, and facilitates the use of antibodies that are non-functional as non-fused soluble protein.  相似文献   
55.
In the present study, we have synthesized novel dihydropyrimidines (1a-j), their dimethylated adducts (2a-j), and hydrazine derivatives (3a-j) of 2a-j and subsequently their pyrazole derivatives (4a-j). Elemental analysis, IR, 1H NMR and mass spectral data elucidated structure of newly synthesized compounds. Some of these novel derivatives showed moderate to potent in vitro antioxidant, anti-inflammatory, antibacterial, antifungal and anthelmintic activity.  相似文献   
56.
We report two unusual autopsy cases with frontotemporal lobar degeneration (FTLD) that were hyperphosphorylated‐tau‐ and TAR DNA binding protein 43 (TDP‐43)‐ negative. The behavioral symptoms in both cases were compatible with frontotemporal dementia, but they exhibited more prominent speech and language related symptoms than previously reported. Moreover, they displayed a short duration of the disease; the male case had a disease onset age of 45 years, and duration of 5 years, and the female case suffered even shorter disease duration and a later onset of the symptoms, at the age of 67 years. Moreover, the motor functions had deteriorated in different ways in these cases. The male patient showed progressive motor symptoms, weakness of extremities and bulbar muscles suggesting motor neuron disease with a muscle biopsy supporting neurogenic deficits, whereas the female patient exhibited dyskinesias and tremor with progressive swallowing disorders. The father of the male case displayed dementia of similar type at the age of 68 years. In both cases, neuropathological examination showed fused‐in sarcoma (FUS)‐positive pathology. The male patient had intensely FUS‐positive cytoplasmic and intranuclear inclusions that resembled the characteristics previously reported in FTLD FUS, whereas the female patient did not exhibit any cytoplasmic inclusions but had roundish, dense FUS‐positive intranuclear inclusions. She also displayed a plethora of other pathologies including α‐synuclein, hyperphosphorylated‐tau, β‐amyloid aggregation and some neuronal polyglutamine aggregation (1C2) but no well‐demarcated inclusions were observed. We conclude that clinical phenotypes of FUS pathologies also include elderly patients and are more variable with motor and speech disorders than previously reported.  相似文献   
57.
目的:探讨钴铬合金和金合金烤瓷冠修复后,患牙各项牙周指数及龈沟液中牙周可疑致病菌检出率的变化,以评价两种合金作为烤瓷冠内冠材料对牙周组织的影响。方法:选择采用钴铬合金和金合金烤瓷冠修复并符合纳入标准的患牙各15颗。于修复前和修复6个月后,临床对比患牙牙周探诊深度、菌斑指数、龈沟出血指数的变化。同时用PCR检测患牙龈沟液中Pg、Aa阳性率的变化。结果:钴铬合金烤瓷冠修复6个月后,牙周探诊深度和龈沟出血指数与修复前比较差异具有显著性意义(P0.05),菌斑指数差异无显著性意义(P0.05);龈沟液中Pg的阳性率较修复前显著性增高(P0.05),而Aa的阳性率无显著性差异(P0.05)。金合金烤瓷冠修复6个月后,牙周探诊深度与修复前比较差异有显著性意义(P0.05),菌斑指数和龈沟出血指数差异均无显著性意义(P0.05);牙龈沟液中Pg和Aa的阳性率增高无统计学意义(P0.05)。结论:钴铬合金烤瓷冠对牙周健康具有一定程度的不良影响,金合金是理想的金属烤瓷冠材料。  相似文献   
58.
PurposeTo investigate the reproducibility of diffusion-weighted (DW) MRI and 18F-Fluorodeoxyglucose (18F-FDG)-Positron emission tomography/CT (PET/CT) in monitoring response to neoadjuvant chemotherapy in epithelial ovarian cancer.Materials and methodsTen women (median age, 67 years; range: 41.8–77.3 years) with stage IIIC-IV epithelial ovarian cancers were included in this prospective trial (NCT02792959) between 2014 and 2016. All underwent initial laparoscopic staging, four cycles of carboplatine-paclitaxel-based chemotherapy and interval debulking surgery. PET/CT and DW-MRI were performed at baseline (C0), after one cycle (C1) and before surgery (C4). Two nuclear physicians and two radiologists assessed five anatomic sites for the presence of ≥ 1 lesion. Target lesions in each site were defined and their apparent diffusion coefficient (ADC), maximal standardized uptake value (SUV-max), SUV-mean, SUL-peak, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were monitored (i.e., 10 patients × 5 sites × 3 time-points). Their relative early and late changes were calculated. Intra/inter-observer reproducibilities of qualitative and quantitative analysis were estimated with Kappa and intra-class correlation coefficients (ICCs).ResultsFor both modalities, inter- and intra-observer agreement percentages were excellent for initial staging but declined later for DW-MRI, leading to lower Kappa values for inter- and intra-observer variability (0.949 and 1 at C0, vs. 0.633 and 0.643 at C4, respectively) while Kappa values remained > 0.8 for PET/CT. Inter- and intra-observer ICCs were > 0.75 for SUV-max, SUL-peak, SUV-mean and their change regardless the time-point. ADC showed lower ICCs (range: 0.013–0.811). ANOVA found significant influences of the evaluation time, the measurement used (ADC, SUV-max, SUV-mean, SUV-max, SUL-peak, MTV or TLG) and their interaction on ICC values (P = 0.0023, P< 0.0001 and P =0.0028, respectively).ConclusionWhile both modalities demonstrated high reproducibility at baseline, only SUV-max, SUL-peak, SUV-mean and their changes maintained high reproducibility during chemotherapy.  相似文献   
59.
Antibody therapy based on PD-1/PD-L1 blocking or ADCC effector has produced significant clinical benefit for cancer patients. We generated a novel anti-B7-H3 antibody (07B) and engineered the Fc fragment to enhance ADCC. To improve efficacy and tumor selectivity, we developed anti-B7-H3/PD-1 bispecific fusion proteins that simultaneously engaged tumor associate marker B7-H3 and immune suppressing ligand PD-L1 as well as enhanced ADCC to promote potent and highly selective tumor killing. Fusion proteins were designed by fusing human PD-1 extra domain to 07B in four different formats and showed good binding capacity to both targets. Indeed, the affinity of fusion proteins to B7-H3 is over 10,000 fold higher compared to that of the analogous PD-L1 and the blocking of fusion proteins to PD-L1 was worse but it greatly enhanced when bound to B7-H3, thus achieving directly PD-L1-blockade to B7-H3-expressing tumor cells. Importantly, IL-2 production was enhanced by fusion proteins from staphylococcal enterotoxin B (SEB) stimulated PBMC. Similarly, cytokines induced by fusion proteins was enhanced when co-cultured with stimulated CD8+ T cells and B7-H3/PD-L1 transfected raji cells. Additionally, fusion proteins improved activation to CD16a by Fc modification and delivered selective cytotoxicity to B7-H3 expressing tumor cells. In conclusion, fusion proteins blocked the PD-1/PD-L1 signal pathway and significantly increased potency of ADCC in a B7-H3-directed manner, thereby selectively activating CD8+ T cells and enhancing natural killing towards tumor. This novel fusion protein with its unique targeting preference may be useful to enhance efficacy and safety of immunotherapy for B7-H3-overexpressing malignancies.  相似文献   
60.
目的构建霍乱毒素B亚单位(CtB)和幽门螺杆菌尿素膜通道蛋白(UreI)融合的原核表达质粒pET32a( )ctB/ureI,并初步研究融合蛋白CtB/UreI的表达特性和免疫特性。方法PCR从pUC18ctB中克隆ctB基因,定向在pET32a( )/ureI的ureI基因5′端插入ctB基因,构建ctB和ureI双基因原核表达质粒pET32a( )ctB/ureI,转该质粒于E.coliBL-21(DE3),经酶切和序列分析鉴定工程菌。IPTG诱导表达,HP-His亲和层析纯化,SDS-PAGE和Gel-ProAnalizer4分析,重组蛋白免疫BALB/c小鼠。用Westernblot和ELISA分析重组蛋白的免疫特性。结果工程菌含完整的ctB和ureI基因,与相对应基因的序列同源性分别为100%。在22℃,1mmol/LIPTG诱导4h后,重组蛋白的表达占菌体总蛋白12%,亲和层析纯化后蛋白纯度为94.3%。Westernblot表明重组蛋白分别能与相应的抗体反应,该蛋白免疫小鼠后能产生相应的IgG抗体。结论成功构建了能表达CtB/UreI蛋白的大肠杆菌表达菌株。对融合蛋白表达和纯化后,初步证明了该重组蛋白有CtB和UreI的双特异反应原性和免疫原性,为研究新型幽门螺杆菌疫苗奠定了坚实的基础。  相似文献   
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