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71.
Given the outstanding room-temperature phosphorescence (RTP) of Mn–ZnS quantum dots (QDs) and the specific recognition performance of the aptamer, we built phosphorescent composites from aptamers conjugated with polyethyleneimine quantum dots (PEI-QDs) and applied them to cytochrome c (Cyt c) detection. Specifically, QDs/CBA composites were generated from the electrostatic interaction between the positively-charged PEI-QDs and the negatively-charged Cyt c binding aptamer (CBA). With the presence of Cyt c, the Cyt c can specifically bind with the QDs/CBA composites, and quench the RTP of QDs through photoinduced electron-transfer (PIET). Thereby, an optical biosensor for Cyt c detection was built, which had a detection range of 0.166–9.96 μM and a detection limit of 0.084 μM. This aptamer-mediated phosphorescent sensor with high specificity and operational simplicity can effectively avoid the interference of scattering light from complex substrates. Our findings offer a new clue for building biosensors based on QDs and aptamers.

In this study, the nanocomposites from polyethyleneimine-capped Mn-doped ZnS QDs (PEI-QDs) and Cyt c binding aptamer (CBA) were prepared and used as Cyt c RTP sensors..  相似文献   
72.
BACKGROUND Transarterial chemoembolization(TACE) and hepatic arterial infusion chemotherapy(HAIC) have shown promising local benefits for advanced hepatocellular carcinoma(HCC). S-1, a composite preparation of a 5-fluorouracil prodrug, has proven to be a convenient oral chemotherapeutic agent with definite efficacy against advanced HCC.AIM To evaluate the efficacy and safety of TACE followed by HAIC with or without oral S-1 for treating advanced HCC.METHODS In this single-center, open-label, prospective, randomized controlled trial, 117 participants with advanced HCC were randomized to receive TACE followed by oxaliplatin-based HAIC either with(TACE/HAIC + S-1, n = 56) or without(TACE/HAIC, n = 61) oral S-1 between December 2013 and September 2017. Two participants were excluded from final analysis for withdrawing consent. The primary endpoint was progression-free survival(PFS) and secondary endpoints included overall survival(OS), objective response rate, disease control rate and safety.RESULTS In total, 115 participants(100 males and 15 females; mean age, 57.7 years ± 11.9) were analyzed. The median PFS and OS were 5.0 mo(0.4–58.6 mo)(95% confidence interval(CI): 3.82 to 6.18) vs 4.4 mo(1.1–54.4 mo)(95%CI: 2.54 to 6.26; P = 0.585) and 8.4 mo(0.4–58.6 mo)(95%CI: 6.88 to 9.92) vs 8.3 mo(1.4–54.4 m)(95%CI: 5.71 to 10.96; P = 0.985) in the TACE/HAIC + S-1 and TACE/HAIC groups, respectively. The objective response rate and disease control rate were 30.9% vs 18.4% and 72.7% vs 56.7% in the TACE/HAIC + S-1 and TACE/HAIC groups, respectively. Grade 3/4 adverse events had a similar frequency in both treatment groups.CONCLUSION No improvements in tumor response rates, PFS or OS were observed with the addition of S-1 to TACE/HAIC in advanced HCC. Both treatment regimens had a similar safety profile.  相似文献   
73.
李俊  魏军平 《中医学报》2020,35(1):11-14
"热证用灸"的思想基础上溯《黄帝内经》。秦汉时期有灸法补泻理论;魏晋时期灸疗用于痈疽肿痛;隋唐时期"热证用灸"应用已从外科阳热痈肿疮疡拓展到内科急证、热证的治疗;宋金元时期"热证用灸"理论的愈加丰富,并广泛应用于临床;明清医家对前人"热证用灸"的理论和应用做了全面继承和总结,同时出现了灸、熨法和药末相结合的神灯照法、太乙神针、雷火神针,提高了灸法用于疮疡肿毒的临床疗效;近现代出现了"热证贵灸"、灸感三相、腧穴热敏化灸、动力灸法、灯火灸、脐灸等理论和方法,有助于"热证用灸"的规范化研究。一方面,历史上还有不少医家持热证禁灸的观点。"热证用灸"的临床适应证和禁忌证尚缺乏系统、完善的研究总结,限制其理论的广泛传播和应用,故在临床诊疗和研究中,应该求同存异,探索和总结其临床适应证。另一方面,随着灸法的现代化研究不断深入,应用科学手段探究灸法疗效的客观化、规范化也越来越多,这也有助于我们更加深入地理解"热证用灸"的作用机理。  相似文献   
74.
Overexpression of epidermal growth factor receptor (EGFR) is associated with resistance to chemotherapy and radiotherapy, advanced tumor stage, invasion, metastasis and poor prognosis in malignant tumors. EGFR, therefore, has been an attractive molecular target for chemotherapy. However, the results of clinical studies using inhibitors of its kinase activity have not been promising because the response rates were at most 20%. Sodium-glucose co-transporter 1 (SGLT1) is a membrane protein that mediates the transport of glucose across cellular membranes. EGFR physically associates with and stabilizes SGLT1 to promote glucose uptake into cancer cells through a kinase-independent process. The purpose of this study was to investigate the coexpression of SGLT1 and EGFR and its relationships with clinicopathological features in oral squamous cell carcinoma (OSCC). SGLT1 and EGFR were detected in all OSCC cell lines, and the expression levels of SGLT1 were significantly correlated with those of EGFR. Pearson product?Cmoment correlation coefficient of SGLT1 and EGFR was 0.89 (P?=?0.016). The immunohistochemical study using the surgical specimens in 52 patients with tongue SCC also showed a significant correlation between SGLT1 and EGFR. Moreover, SGLT1/EGFR expression was inversely related to tumor differentiation among the 5 clinicopathological factors (P?=?0.004). SGLT1/EGFR coexpression might be required in the de-differentiation of OSCC, but further study is needed to clarify the implication of these proteins in the manifestation of malignancy and clinical significance.  相似文献   
75.
76.
In our previous studies, we showed that frontal lobe and brainstem functions were abnormal in online game addicts. In this study, 14 students with Internet addiction disorder and 14 matched healthy controls underwent proton-magnetic resonance spectroscopy to measure cerebral function. Results demonstrated that the ratio of N-acetylaspartate to creatine decreased, but the ratio of cho- line-containing compounds to creatine increased in the bilateral frontal lobe white matter in people with Internet addiction disorder. However, these ratios were mostly unaltered in the brainstem, suggesting that frontal lobe function decreases in people with Internet addiction disorder.  相似文献   
77.
诺贝尔生理学或医学奖是生物医学奖中的最高奖项,在生理学教学中加入诺贝尔生理学或医学奖的教育推进器能提高教学质量,及培养学生的综合素质和科研创新能力。  相似文献   
78.
Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer. Our objective was to discuss the limited ESD reports available and to determine the lesions suitable for use in training endoscopists on which lesions are appropriate for ESD. We reviewed a series of ESD reports that have been written on various risk factors related to the resectability or curability of a variety of lesions. These published studies show that certain risk factors such as tumor size and location and the presence of ulceration are closely related to both resectability and curability. Because the combination of these risk factors resulted in a much higher risk than did any single factor, we recently established a 'risk assessment chart' to determine an individual's total risk of treatment failure for early gastric cancer that has been treated using ESD. This risk chart provides a clear indication that small, non-ulcerated lesions located in the lower third of the stomach have a high rate of curative resection and are technically less challenging if ESD is used. We suggest that trainees should gain ESD experience with such lesions before they start to perform ESD on more difficult lesion types that have a lower probability of curative resection. In addition, we suggest that this risk assessment chart is suitable for the pretreatment assessment of curability and the likelihood of successful en bloc resection.  相似文献   
79.
We previously reported that anti-amyloid-beta (Aβ) single-chain antibody (scFv59) brain delivery via recombinant adeno-associated virus (rAAV) was effective in reducing cerebral Aβ load in an Alzheimer’s disease (AD) mouse model without inducing inflammation. Here, we investigated the prophylactic effects and mechanism of a muscle-directed gene therapy modality in an AD mouse model. We injected rAAV serotype 1 encoding scFv59 into the right thigh muscles of 3-month-old mice. Nine months later, high levels of scFv59 expression were confirmed in the thigh muscles by both immunoblotting and immunohistochemistry. As controls, model mice were similarly injected with rAAV1 encoding antihuman immunodeficiency virus Gag antibody (scFvGag). AAV1-mediated scFv59 gene delivery was effective in decreasing Aβ deposits in the brain. Compared with the scFvGag group, levels of Aβ in cerebrospinal fluid (CSF) decreased significantly while Aβ in serum tended to increase in the scFv59 group. AAV1-mediated scFv59 gene delivery may alter the equilibrium of Aβ between the blood and brain, resulting in an increased efflux of Aβ from the brain owing to antibody-mediated sequestration/clearance of peripheral Aβ. Our results suggest that muscle-directed scFv59 delivery via rAAV1 may be a prophylactic option for AD and that levels of CSF Aβ may be used to evaluate the efficacy of anti-Aβ immunotherapy.  相似文献   
80.
正Primary leiomyosarcoma of the inferior vena cava(IVC) is a rare disease, accounting for 0.5% of soft tissue sarcomas in adults [1]. A diversity of therapeutic methods have been applied to treat this type of tumor. The average survival time of patients who are not treated is merely 3-4 months [2]. The effect of radiotherapy and chemotherapy remains unclear and controversial [3].  相似文献   
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