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81.
文题释义:干细胞肝向分化:是指来自于胚胎、胎儿或成体内具有在一定条件下无限制自我更新与增殖分化能力的一类细胞,通过形态、功能的特殊变化,建立起肝细胞特征的过程。这一过程与细胞分裂共同发生,并伴随干细胞多能性的减弱与肝功能表达的增强。 生物人工肝:是以培养肝(样)细胞为基础的生物或混合生物人工肝支持系统。它的基本要素包括高活性和功能的肝(样)细胞、适合的生物反应器与外部控制系统、有效的体外循环系统,可通过暂时或部分替代肝脏功能,实现对肝脏功能不全或相关疾病的治疗。  摘要背景:干细胞在组织工程学、再生医学、细胞治疗以及药物研究方面具有巨大的应用前景。近年来,以生物人工肝为例的应用研究需要大规模扩增出高质量的干细胞并最终定向分化为肝(样)细胞。如何通过此途径高效获得一致性、功能性完好并且标志物均匀表达的分化细胞,是需要解决的关键问题。目的:对干细胞扩增及肝向分化过程相关检测指标与检测方法进行综述,总结已应用于在线检测的指标与方法,讨论部分指标与方法应用于在线检测的局限性,并对未来有望应用于在线检测的指标和检测技术进行展望。 方法:由第一作者检索1990至2019年PubMed数据库、Web of Science核心合集、Elsevier数据库、中国知网等收录的与干细胞扩增及肝向分化过程相关的文献。英文检索词为“stem cells,expansion,hepatic differentiation,monitoring,real-time online”,中文检索词为“干细胞,扩增,肝向分化,监测,实时在线”,共计检索93篇文章,最终筛选了符合标准的53篇进行综述。结果与结论:干细胞扩增及肝向分化过程的相关检测指标与检测方法众多,其中扩增过程的检测指标主要涉及干细胞多能性的保持、代谢活性、存活率以及转癌趋势。肝向分化过程因细胞种类而异,其中多能干细胞和中胚层谱系成体多能干细胞要先向内胚层定向分化,再分化为成熟肝(样)细胞,而以肝干/祖细胞为主的内胚层谱系成体多能干细胞可直接分化为成熟肝(样)细胞。分化过程不同阶段细胞的特异性标志物、存活率以及代谢活性是检测的重点。目前,基于大型生化检测分析设备的检测方法虽然可靠性高,但面临实时性差、成本高、难以集成小型化等问题。未来,干细胞扩增及肝向分化过程中关键检测指标的筛选、检测标准的量化以及自动化在线检测的实现,需要重点研究。ORCID: 0000-0002-3881-5577(吴昌哲);0000-0002-6052-8400(杨嘉屹)中国组织工程研究杂志出版内容重点:干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程  相似文献   
82.
Designing high accuracy in the diagnosing and fault-freely eliminating lymphatic metastasis of breast malignancy, to avoid the invasiveness and complications caused by traditional assays, is of great therapeutic importance. To this end, theranostic W18O49 nanoparticles targeting to human epidermal growth receptor 2 (HER-2) over-expressed breast malignancy were synthesized via polyol method. By taking advantage of their high X-ray attenuating and photothermotherapy potency, lymph nodes in the mice bearing HER-2 positive metastasis could be clearly distinguished under CT guidance and selectively eliminated by laser ablation. The therapeutic efficacy was further confirmed by the significantly extended survival period. These finding evidenced the potential of these nanoparticles for imaging guided photothermal ablation of HER-2 positive breast malignancy.  相似文献   
83.
ABSTRACT

Introduction: The development of point-of-care testing (POCT) has made clinical diagnostics available, affordable, rapid, and easy to use since the 1990s.The significance of this platform rests on its potential to empower patients to monitor their own health status more frequently, in the convenience of their home, so that diseases can be diagnosed at the earliest possible time-point. Recent advances have expanded traditional formats such as qualitative or semi-quantitative dipsticks and lateral flow immunoassays to newer platforms such as microfluidics and paper-based assays where signals can be measured quantitatively using handheld devices.

Areas covered: This review discusses: (1) working principles and operating mechanisms of both existing and emerging POCT platforms, (2) urine analytes measured using POCT in comparison to the laboratory or clinical ‘gold standard,’ and (3) limitations of existing POCT and expectations of emerging POCT in urinalysis.

Expert opinion: Currently, a variety of biological samples such as urine, saliva, serum, plasma, and other fluids can be applied to POCT for quick diagnosis, especially in resource-limited settings. Emerging platforms will increasingly empower individuals to monitor their health status through frequent urine analysis even from their homes. The impact of these emerging technologies on healthcare is likely to be transformative.  相似文献   
84.
Grass carp reovirus (GCRV) is a severe virus that causes great losses to grass carp culture every year, and GCRV-II is the current popular and fatal strain. VP56, fibrin on the outer surface of GCRV-II, mediates cell attachment. In this study, we firstly divided the VP56 gene into four fragments to screen the optimal antigen by enzyme-linked immunosorbent assay and neutralizing antibody methods. The second fragment VP56-2 demonstrates the optimal efficiency and was employed as an antigen in the following experiments. Bacillus subtilis were used as a carrier, and VP56-2 was expressed on the surface of the spores. Then, we performed the oral immunization for grass carp and the challenge with GCRV-II. The survival rate was remarkably raised, and mRNA expressions of IgM were significantly up-regulated in spleen and head kidney tissues in the B. s-CotC-VP56-2 group. Three crucial immune indexes (complement C3, lysozyme and total superoxide dismutase) in the sera were also significantly enhanced. mRNA expressions of four important genes (TNF-α, IL-1β, IFN1 and MHC-II) were significantly strengthened. Tissue lesions were obviously attenuated by histopathological slide examination in trunk kidney and spleen tissues. Tissue viral burdens were significantly reduced post-viral challenge. These results indicated that the oral recombinant B. subtilis VP56-2 subunit vaccine is effective for controlling GCRV infection and provides a feasible strategy for the control of fish virus diseases.  相似文献   
85.
Objective: To evaluate the diagnostic efficacy of gastric juice–based genotypic methods for Helicobacter pylori detection and antibiotic resistance testing.Methods: We used electronic databases including MEDLINE, EMBASE, Web of Science, and the Cochrane Central Register of Controlled Trial for literature survey using keywords such as “gastric juice,” “Helicobacter pylori,” and their synonyms. The quality of the studies was assessed using QUADAS-2. Summary performance measures (sensitivity, specificity, positive predictive values, negative predictive values, diagnostic odds ratio, and area under the summary receiver-operating characteristic curve) and HSROC curves were produced. In addition, Fagan plots were applied to illustrate the relationship among the prior test probability, PLR/NLR, and posterior test probability.Results: Our study cohort comprised eight studies with 1235 participants (617 participants with H. pylori infection and 618 participants with non-H. pylori infection). Pooled sensitivity and specificity with a corresponding 95% CI of gastric juice–based genotypic methods reflected values of 94% (95% CI, 86%-98%) and 98% (95% CI, 85%-100%), respectively. The global sensitivity and specificity of clarithromycin resistance were 92% (95% CI, 85%-96%) and 90% (95% CI, 80%-95%), respectively.Conclusion: Gastric juice–based genotypic methods can be used for diagnostic prediction of H. pylori infection as well as clarithromycin resistance testing.  相似文献   
86.
晚期癌症患者生活质量评估方法改进的初步意见   总被引:6,自引:0,他引:6  
目的完善晚期癌症患者生活质量评估标准,使之适合晚期癌症患者实际情况并具有患者及家属自我测试功能。方法在我国1990年制定的生活质量评估草案的基础上对评估的具体标准,评分比例以度个别项目作出删除及增补。并将我院收治的晚期癌症患者181例分别用草案标准及修改后标准进行评估,将评估结果进行比较。结果草案评估法评估结果病例分布不够合理,过于偏向“差”级别。修改后评估法得出的结果病例分布里正常分布。结论修改后生活质量评估方法比草案评估方法更适合患者及家属自我测评,且更符合现代生物-心理-社会医学模式。  相似文献   
87.
European Archives of Oto-Rhino-Laryngology - The creation of bone flaps which can be later repositioned and fixed in situ for repairing the bone defects during the endoscopic endonasal approaches...  相似文献   
88.
Apparent treatment‐resistant hypertension (aTRH) is the most commonly used term to report resistant hypertension (RH) and is considered as a common problem in dialysis population. However, few reports have focused on peritoneal dialysis (PD) hypertensive patients. The authors conducted a multi‐center cross‐sectional study involving 1789 PD patients from nine centers in Guangdong, China. The prevalence of aTRH was estimated by home blood pressure (BP) monitoring. Evaluating drug adherence through Eight‐item Morisky Medication Adherence Scale (MMAS‐8) and pill counting was performed to assess RH in one PD center. Related factors of aTRH were analyzed using logistic regression analysis. The prevalence of aTRH in PD patients was estimated at 42.2% (755 out of 1789 hypertensive patients) based on home BP. Of those, 91.4% patients were classified as uncontrolled RH, 2.0% as controlled RH, and 6.6% as refractory hypertension. The prevalence of RH was 40.6% and 41.9% among those with medium/high adherence based on the MMAS‐8 scores and the pill counting rate, respectively. PD patients who were younger, with higher body mass index, with lower serum albumin and poorer dialysis adequacy were significantly associated with higher aTRH incident. In conclusion, the present study demonstrates a high prevalence of aTRH in PD population, which occurs in about two in five treated hypertensive patients. Nutritional status and dialysis adequacy might tightly associate with aTRH.  相似文献   
89.
In-plane elastic and interlaminar properties of composite laminates are commonly obtained through separate experiments. In this paper, a simultaneous identification method for both properties using a single experiment is proposed. The mechanical properties of laminates were treated as uncertainties and Bayesian inference was employed with measured strain-load curves in compression tests of laminates with embedded delamination. The strain–load curves were separated into two stages: the pre-delamination stage and the post-delamination stage. Sensitivity analysis was carried out to determine the critical properties at different stages, in order to alleviate the ill-posed problem in inference. Results showed that the in-plane Young’s modulus and shear modulus in elastic properties are dominant in the pre-delamination stage, and the interlaminar strength and type I fracture toughness in interlaminar properties are dominant in the post-delamination stage. Five times of property identification were carried out; the maximum coefficient of variation of identified properties was less than 1.11%, and the maximum error between the mean values of the identified properties and the ones from standard experiments was less than 5.44%. The proposed method can reduce time and cost in obtaining multiple mechanical properties of laminates.  相似文献   
90.
目的 分析显微外科手术治疗脑胶质瘤的临床疗效.方法 回顾性分析78例脑胶质瘤显微手术治疗的临床资料.结果 72例病人术前诊断与术后病理诊断符合率92.3%.经手术治疗显效38例(48.7%),有效35例(44.9%),无效5例(6.4%),治疗总有效率93.6%.结论 显微手术以其损伤小、适应证宽、全切除率高等优点,临床效果好.  相似文献   
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