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91.
Surface treatment is known as a very efficient measure by which to modulate the surface properties of biomaterials in terms of grain structure, topography, roughness and chemistry to determine the osseointegration of implants. In this work, a two-step method of surface modification was employed to impart high osteogenic activity and biomineralization capacity on a Ti–25Nb–3Mo–2Sn–3Zr alloy (a type of β-titanium named TLM). The preliminary surface mechanical attrition treatment (SMAT) refined the average grain size from 170 ± 19 μm to 74 ± 8 nm in the TLM surface layer and promoted the surface to be much rougher and more hydrophilic. The subsequent Ca-ion implantation did not change the surface roughness and topography obviously, but enhanced the surface wettability of the SMAT-treated TLM alloy. The in vitro evaluations of the adhesion, proliferation, osteogenic genes (RUNX2, ALP, BMP-2, OPN, OCN and COL-I) and protein (ALP, OPN, OCN and COL-I) expressions, as well as extracellular matrix (ECM) mineralization of mesenchymal stem cells (MSCs) revealed that the initial SMAT-treated sample significantly enhanced the adhesion and osteogenic functions of MSCs compared to an untreated TLM sample, and the subsequent introduction of Ca ions onto the SMAT-derived nanograined sample further promotes the MSC adhesion, proliferation, osteo-differentiation and ECM mineralization due to the adsorption of more proteins such as laminin (Ln), fibronectin (Fn) and vitronectin (Vn) on the surface, as well as the increase in extracellular Ca concentrations. In addition, the biomineralization capacity of the samples was also evaluated by soaking them in simulated bodily fluid (SBF) at 37 °C for 28 days, and the results showed that the Ca-ion implanted sample significantly boosted the deposition of Ca and P containing minerals on its surface, which was associated with the generation of more Ti–OH groups on the surface after ion implantation. The combination of the SMAT technique and Ca-ion implantation thus endowed the TLM alloy with outstanding osteogenic and biomineralization properties, providing a potential means for its future use in the orthopedic field.

Combination of the SMAT technique and Ca-ion implantation produced a β-titanium alloy with a bioactive surface layer, which was proved to effectively promote the osteogenic activity of MSCs and Ca–P mineral deposition in vitro.  相似文献   
92.
ObjectiveReconstruction of the digestive tract for adenocarcinoma of esophagogastric junction (AEG) is in dispute. This study evaluated Cheng’s gastric tube interposition esophagogastrostomy with reconstruction of His angle and fundus (Cheng’s GIRAFFE anastomosis) in laparoscopic/open proximal gastrectomy for Siewert type II AEG, which was performed at Zhejiang Cancer Hospital and the First Affiliated Hospital of Zhejiang Chinese Medical University. Here, we discuss the preliminary results of gastric emptying and anti-reflux.MethodsFrom a retrospective database, 74 patients with advanced Siewert type II AEG underwent curative proximal gastrectomy with GIRAFFE anastomosis, and their gastric emptying and anti-reflux outcomes were evaluated by the Reflux Disease Questionnaire (RDQ) score, nuclide gastric emptying, 24-h impedance-pH monitoring and gastroscopy.ResultsSeventy-four patients successfully completed proximal partial gastrectomy with Cheng’s GIRAFFE esophagogastric anastomosis. RDQ score six months after the operation was 2.2±2.5. Results of nuclide gastric emptying examinations showed that the gastric half-emptying time was 67.0±21.5 min, the 1-h residual rate was (52.2±7.7)%, the 2-h residual rate was (36.4±5.1)%, and the 3-h residual rate was (28.8±3.6)%; 24-h impedance-pH monitoring revealed that the mean DeMeester score was 5.8±2.9. Reflux esophagitis was observed by gastroscopy in 7 patients six months after surgery.ConclusionsCheng’s GIRAFFE anastomosis is safe and feasible for Siewert type II AEG.  相似文献   
93.
94.
目的:探讨灵芪胶囊对H22荷瘤小鼠的抑瘤作用及其抑瘤作用机制。方法:采用体内实验法,于无菌条件下抽取传代7d、生长良好的H22荷瘤小鼠腹水,无菌0.9%氯化钠溶液1:3稀释(约含瘤细胞2×10^6/ml),按0.2ml/7,接种于消毒后的小鼠右前肢腋部皮下,制成肿瘤模型,灌胃给药灵芪胶囊11d后,称取小鼠体重,脱椎处死小鼠,取脾脏及胸腺称重并计算胸腺指数和脾脏指数。用免疫组化法检测各组凋亡相关基因突变型p53和bcl-2基因的表达。结果:灵芪胶囊在明显抑制肿瘤生长的同时不降低体重,在一定剂量对荷瘤动物的免疫器官指数无明显影响;灵芪胶囊三个剂量组突变型p53基因和bcl-2基N的表达均低于模型组。结论:灵芪胶囊对H22荷瘤小鼠有明显抑瘤作用,其机制可能与抑制突变型p53基N和bcl-2基因表达有关。  相似文献   
95.
目的介绍近年来适用于妇科恶性肿瘤化疗的药物涉及时辰方案设计的研究成果,方法通过搜集并整理近年来国内外时辰化疗的相关临床和临床前试验的相关文献结果与结论应用时辰化疗理论,改进妇科肿瘤患者化疗方案和给药时间,可以有效降低化疗药物的毒副作用,较常规治疗具有优势,但不同人群、不同种族间的时辰依赖性是否存在差异,有待于进一步研究、  相似文献   
96.
本文采用负染和超薄切片技术在电镜下的观察,研究了国产头孢三嗪在高浓度下和亚最低抑菌浓度下对金葡菌、大肠杆菌和绿脓杆菌超微结构的作用。结果显示,10MIC的头孢三嗪作用3小时即可导致细菌发生不可逆性改变,出现细胞膜皱缩,胞质稀疏,细胞膜连续性丧失,甚至细胞破裂,解体死亡。经Sub-MIC的头孢三嗪作用后,金葡菌呈现菌体增大,横膈增宽;而大肠杆菌和绿脓杆菌则表现为菌体增长和菌丝体形成,胞内出现大小不一的空泡,电子密度下降.本研究证实了头孢三嗪为一杀菌类抗生素;提示本药对细菌的形态学改变,主要由于和PBP_3结合所致。  相似文献   
97.
杜鸣  唐波  沈含熙 《药学学报》1997,32(9):695-698
酪氨酸、色氨酸和苯丙氨酸具有荧光,本文使用互相垂直的偏振片有效地消除了苯丙氨酸的干扰和溶剂散射光的影响;附加滤光片,进一步提高了酪氨酸与色氨酸荧光测定的选择性。线性范围分别为0.02~12.0mg·L-1(酪氨酸)与0.01~2.5mg·L-1(色氨酸)。此法可直接用于氨基酸注射液和动、植物浸出液中游离酪氨酸、色氨酸的分析,结果满意。  相似文献   
98.
The possibility of using commercial bayberry tannin (BT) from a Chinese source as a cross-linker and functional additive to develop soybean protein isolate (SPI)-based films was explored in this study by using the solvent casting method. In particular, the impacts of BT loading on the tensile strength, microstructure, thermal stability, water resistance and antioxidant capacity were fully investigated. The results reveal that SPI incorporated with BT yielded a phenolic–protein hybrid whose relevant films exhibited an improvement in tensile strength of around two times greater compared with native SPI as a result of the formed interactions and covalent cross-links, which could be proven using FTIR spectroscopy. The introduction of BT also led to the compact microstructure of SPI–BT films and enhanced the thermal stability, while the water vapor permeability was reduced compared with the control SPI film, especially at high loading content of tannin. Additionally, the use of BT significantly promoted the antioxidant capacity of the SPI-based films according to DPPH radical scavenging assay results. On this basis, Chinese bayberry tannin is considered a promising natural cross-linker and multifunctional additive that can be dedicated to developing protein-derived films with antioxidant activity for food packaging applications.  相似文献   
99.
Objective: China is a developing country with urban–rural disparities and accelerating population aging. Therefore, quantifying the effects of population aging on the cancer mortality burden is urgently needed.Methods: Using data from China’s death surveillance datasets(2004–2017), we decomposed and quantified the effects of population aging and factor variations on cancer mortality rates in urban and rural China during 2004–2017 through a decomposition method. R ratios were used to assess the e...  相似文献   
100.
Objective: Lung cancer is the most common cause of cancer-related deaths worldwide. Somatic copy number alterations(SCNAs) have been used to predict responses to therapies in many cancers, including lung cancer. However, little is known about whether they are predictive of radiotherapy outcomes. We aimed to understand the prognostic value and biological functions of SCNAs.Methods: We analyzed the correlation between SCNAs and clinical outcomes in The Cancer Genome Atlas data for 486 patients wit...  相似文献   
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