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排序方式: 共有261条查询结果,搜索用时 44 毫秒
21.
Nanoelectromechanical Chip (NELMEC) Combination of Nanoelectronics and Microfluidics to Diagnose Epithelial and Mesenchymal Circulating Tumor Cells from Leukocytes
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Seied Ali Hosseini Mohammad Abdolahad Somayeh Zanganeh Mahyar Dahmardeh Milad Gharooni Hamed Abiri Alireza Alikhani Shams Mohajerzadeh Omid Mashinchian 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(7):883-891
An integrated nano‐electromechanical chip (NELMEC) has been developed for the label‐free distinguishing of both epithelial and mesenchymal circulating tumor cells (ECTCs and MCTCs, respectively) from white blood cells (WBCs). This nanoelectronic microfluidic chip fabricated by silicon micromachining can trap large single cells (>12 µm) at the opening of the analysis microchannel arrays. The nature of the captured cells is detected using silicon nanograss (SiNG) electrodes patterned at the entrance of the channels. There is an observable difference between the membrane capacitance of the ECTCs and MCTCs and that of WBCs (measured using SiNG electrodes), which is the key indication for our diagnosis. The NELMEC chip not only solves the problem of the size overlap between CTCs and WBCs but also detects MCTCs without the need for any markers or tagging processes, which has been an important problem in previously reported CTC detection systems. The great conductivity of the gold‐coated SiNG nanocontacts as well as their safe penetration into the membrane of captured cells, facilitate a precise and direct signal extraction to distinguish the type of captured cell. The results achieved from epithelial (MCF‐7) and mesenchymal (MDA‐MB231) breast cancer cells circulated in unprocessed blood suggest the significant applications for these diagnostic abilities of NELMEC. 相似文献
22.
p53蛋白是反映细胞增殖活性的重要指标,与胃肠肿瘤的发生发展密切相关。结合病理形态学观察,检测p53蛋白的表达,能更客观、准确地判断胃肠肿瘤的恶性程度和预后。对胃肠肿瘤的诊断和预后有较高的临床实用价值。 相似文献
23.
Mabbott Donald J.; Penkman Louise; Witol Adrienne; Strother Douglas; Bouffet Eric 《Canadian Metallurgical Quarterly》2008,22(2):159
Identifying cognitive deficits associated with pediatric brain tumors and their treatment is important in delineating the mechanisms of intellectual decline often associated with these diseases. The authors evaluated sustained attention, information processing speed, working memory, and IQ in 64 patients with posterior fossa tumors, including those treated with either: (a) surgery and cranial radiation (n = 32), and (b) surgery without radiation (n = 32). Ten patients treated for non-CNS solid tumors were included as a comparison group. The authors also examined the impact of relevant demographic and medical variables on neurocognitive outcome. The authors found that neither age at, nor time since, diagnosis predicted cognitive outcome in this sample. Further, sustained attention and working memory were largely intact and there were no differences between groups. Patients treated with cranial radiation demonstrated lowered short-form IQ and slow information processing speed: Patients treated with cranial radiation and who experienced postsurgical complications demonstrated the poorest performance. The authors consider information processing speed to be an excellent candidate mechanism in understanding the impact of cranial radiation on intellectual outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Cong Li Jinsong Xia Xunbin Wei Huihui Yan Zhan Si Shenghong Ju 《Advanced functional materials》2010,20(14):2222-2230
Imaging tumors in their early stages is crucial to increase the surviving rate of cancer patients. Currently most fluorescence probes visualize the neoplasia by targeting the tumor‐associated receptor over‐expressed on the cancer cell membrane. However, the expression level of these receptors in vivo is hard to predict, which limits their clinical translation. Furthermore, the signal output of these receptor‐targeting probes usually stays at a high level, which leads to a strong background signal in normal tissue due to non‐specific binding. In contrast to receptors, characteristics of the tumor microenvironment – such as acidosis – are pervasive in almost all solid tumors and can be easily accessed. In this work, a novel biodegradable nanoprobe InNP1 that demonstrates pH‐activated near‐infrared (NIR) fluorescence in both human glioblastoma U87MG cancer cells in vitro and the subcutaneous U87MG tumor xenografts in vivo is developed. Bio‐distribution, in vivo optical imaging, and autoradiography studies demonstrate that the pH‐activated NIR fluorescence is the dominant factor responsible for the high tumor/normal tissue (T/N) ratio of InNP1 in vivo. Overall, the work provides a nanoprobe prototype to visualize the solid tumor in vivo with high sensitivity and minimal systemic toxicity by sensing the tumor acidic microenvironment. 相似文献
25.
目的:探讨胰腺实性假乳头状瘤(SPTP)的临床特征、治疗及其预后。方法回顾性分析经手术及病理检查证实的10例 SPTP 患者的临床资料。结果10例患者术后恢复良好,均未出现胆瘘、胰瘘及糖尿病等并发症。8例患者行免疫组织化学检测,其中 NSE 阳性8例,阳性表达率为100.0%;Syn、Vim 和 PR 阳性各7例,阳性表达率均为87.5%;Ki-67部分阳性6例,阳性表达率为75.0%;CK 局灶阳性4例,阳性表达率为50.0%;CD99阳性3例,阳性表达率为37.5%;CK18局灶阳性2例,CD10阳性2例,阳性表达率均为25.0%;CD56、α-AT、α-ACT 和CgA 阳性各1例,阳性表达率均为12.5%;EMA 阴性8例,阴性表达率为100.0%。2例患者未行免疫组织化学检测。10例患者随访时间为6~72个月,均未发现肿瘤复发及转移。结论SPTP 是一种潜在低度恶性肿瘤,可能来源于胰腺胚胎多能干细胞,手术切除是首选的治疗方法。 相似文献
26.
目的:探讨射频辅助脾部分切除术治疗脾脏良性肿瘤的疗效及对免疫功能的影响。方法将40例行手术治疗的脾脏良性肿瘤患者根据手术方式的不同,分为射频组(22例,射频辅助脾部分切除术)和对照组(18例,常规脾部分切除术)。对2组患者的手术相关指标(手术时间、手术出血量、住院时间、住院费用、术后并发症),术前、术后4周外周血免疫球蛋白(IgG、IgA、IgM)及 T 淋巴细胞亚群(CD4+、CD8+、CD4+/CD8+)的情况进行比较。结果2组患者的手术时间、住院费用及术后并发症发生例数比较差异均无统计学意义(均 P >0.05)。射频组的手术出血量及住院时间显著少于对照组(均 P <0.05),术后无并发症发生;对照组有 2例患者因术后大出血再次手术治疗。射频组患者术后4周免疫球蛋白及 T 淋巴细胞亚群与术前及对照组比较差异均无统计学意义(均 P >0.05)。结论射频辅助脾部分切除术可有效地治疗脾脏良性肿瘤,出血量少、住院时间短,且不损害患者免疫功能。 相似文献
27.
Paweł Reichert Tomasz Gołębiowski Przemysław Kowalski Jerzy Gosk 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(4):E45-E48
The article presents a case report about a 38‐year‐old hemodialyzed woman who presented to our department with a painful, expansile, lytic bone lesion of the fifth metacarpal epiphysis. The lesion was resected and replaced by corticocancellous bone graft. At 3 months, imaging suggested signs of graft resorption and local recurrence which necessitated repeat excision and grafting. Because of secondary parathyroidism subsequent subtotal parathyroidectomy was performed. This procedure leads to appropriate bone remodeling by 8 weeks postoperatively, and recurrence has not been observed at 2 years of follow up. 相似文献
28.
Dual‐pH Sensitive Charge‐Reversal Polypeptide Micelles for Tumor‐Triggered Targeting Uptake and Nuclear Drug Delivery
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Shi‐Song Han Ze‐Yong Li Jing‐Yi Zhu Kai Han Zheng‐Yang Zeng Wei Hong Wen‐Xin Li Hui‐Zhen Jia Yun Liu Ren‐Xi Zhuo Xian‐Zheng Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(21):2543-2554
A novel dual‐pH sensitive charge‐reversal strategy is designed to deliver antitumor drugs targeting to tumor cells and to further promote the nuclei internalization by a stepwise response to the mildly acidic extracellular pH (≈6.5) of a tumor and endo/lysosome pH (≈5.0). Poly(l ‐lysine)‐block–poly(l ‐leucine) diblock copolymer is synthesized and the lysine amino residues are amidated by 2,3‐dimethylmaleic anhydride to form β‐carboxylic amide, making the polypeptides self‐assemble into negatively charged micelles. The amide can be hydrolyzed when exposed to the mildly acidic tumor extracellular environment, which makes the micelles switch to positively charged and they are then readily internalized by tumor cells. A nuclear targeting Tat peptide is further conjugated to the polypeptide via a click reaction. The Tat is amidated by succinyl chloride to mask its positive charge and cell‐penetrating function and thus to inhibit nonspecific cellular uptake. After the nanoparticles are internalized into the more acidic intracellular endo/lysosomes, the Tat succinyl amide is hydrolyzed to reactivate the Tat nuclear targeting function, promoting nanoparticle delivery into cell nuclei. This polypeptide nanocarrier facilitates tumor targeting and nuclear delivery simultaneously by simply modifying the lysine amino residues of polylysine and Tat into two different pH‐sensitive β‐carboxylic amides. 相似文献
29.
30.
Jun Hu Yong'an Tang Ahmed H. Elmenoufy Huibi Xu Zhen Cheng Xiangliang Yang 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(44):5860-5887
Photodynamic therapy (PDT), as an emerging clinically approved modality, has been used for treatment of various cancer diseases. Conventional PDT strategies are mainly focused on superficial lesions because the wavelength of illumination light of most clinically approved photosensitizers (PSs) is located in the UV/VIS range that possesses limited tissue penetration ability, leading to ineffective therapeutic response for deep‐seated tumors. The combination of PDT and nanotechnology is becoming a promising approach to fight against deep tumors. Here, the rapid development of new PDT modalities based on various smartly designed nanocomposites integrating with conventionally used PSs for deep tumor treatments is introduced. Until now many types of multifunctional nanoparticles have been studied, and according to the source of excitation energy they can be classified into three major groups: near infrared (NIR) light excited nanomaterials, X‐ray excited scintillating/afterglow nanoparticles, and internal light emission excited nanocarriers. The in vitro and in vivo applications of these newly developed PDT modalities are further summarized here, which highlights their potential use as promising nano‐agents for deep tumor therapy. 相似文献