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51.
Binbin Zhang Wenxia Liu Yihao Liu Zhiguang Suo Lingyan Feng Feifei Xing Shourong Zhu 《RSC advances》2019,9(42):24638
An inorganic titanium oxide (TiO) gel sensor was demonstrated for convenient detection of ascorbic acid (AA). It is composed of TiO (PI–TiO) functionalized with a perylene diimide derivative containing carboxylic groups as a new soft dopant material. A traditional solvothermal reaction is adopted to prepare the PI–TiO composite, which exhibits a different spectrum according to the reaction time. The final gel possesses a strong chelating affinity with AA molecules, in which phenol hydroxyl groups are shown to compete with those already present in PI. We further utilize the functionalized gel to prepare a series of films with a simple and portable AA response. A visual colour variation can be recognized by the naked eye, together with obvious fluorescence changes for selective and sensitive AA detection. Finally, the as-prepared gel film displays good stability and reproducibility for real sample responses with satisfying results.A fluorescent inorganic titanium oxide gel sensor was prepared from perylene diimide functionalized composite materials, and applied for sensitive and portable ascorbic acid detection. 相似文献
52.
目的总结运用同期两镜或三镜术中留置输尿管导管胆管引流的治疗经验。方法从1992年10月-2014年8月,我们运用同期两镜或三镜术中留置输尿管导管胆管引流的手术方式,即腹腔镜术中经胆囊管残端输尿管导管胆管引流术(LUD),对207例患者进行治疗。结果 181例胆管引流获得成功(87.4%)。输尿管导管插管失败12例(5.8%),其中中转为鼻胆管引流7例,T管引流2例,放弃胆管引流3例。输尿管导管打折或堵塞导致无任何液体流出2例(1.0%)。输尿管导管早期滑脱导致胆汁性腹膜炎2例(1.0%),再次腹腔镜下放置输尿管导管及腹腔引流管1例和放置T管及腹腔引流管1例而治愈。术后胆漏4例(1.9%),经腹腔引流管引流自愈。乳头切开术后发生轻症胰腺炎3例(1.4%)。术后经输尿管导管胆管造影无残石,胆管切口一期缝合术后有轻度狭窄影像2例未处理,乳头区狭窄影像1例未处理。无其他严重并发症,无死亡。结论只要选择合适的病例,同期两镜或三镜术中留置输尿管导管胆管引流是可行、有效和安全的。 相似文献
53.
Wenfei Lv Yahui Lin Weihua Song Kai Sun Hui Yu Yinhui Zhang Channa Zhang Liang Li Miaomiao Suo Rutai Hui Jingzhou Chen 《Journal of molecular neuroscience : MN》2014,53(2):196-203
Type III collagen plays an important role in activating platelets, forming thrombus, and maintaining the mechanical properties of arteries. This study aimed to test the hypothesis that genetic variants of COL3A1 (gene encoding type III collagen) contribute to recurrence and prognosis of stroke. We investigated the associations of three variants (rs2138533, rs11887092, and rs1800255) in the COL3A1 gene with stroke recurrence and prognosis in 1,544 patients with three subtypes of stroke: lacunar infarction (n?=?442), atherothrombotic infarction (n?=?670), and hemorrhage (n?=?432). These associations were evaluated by Kaplan–Meier analysis and Cox regression models. Patients were followed up for 4.5 years. The A allele of rs1800255 in the COL3A1 gene coding region was significantly associated with a reduced risk of stroke recurrence in patients with lacunar infarction (adjusted hazard ratio [HR] 0.58, 95 % confidence interval [CI] 0.36–0.93, P?=?0.024), but there was an increased risk of all-cause mortality of atherothrombotic patients (adjusted HR 1.43, 95 % CI 1.01–2.00, P?=?0.044). The TT genotype of rs2138533 showed a significantly increased risk of death caused by cardiovascular disease or stroke in lacunar infarct patients (adjusted HR 2.98, 95 % CI 1.27–6.98, P?=?0.012), but there was a reduced risk of all-cause mortality for patients with intracerebral hemorrhage (adjusted HR 0.34, 95 % CI 0.12–0.93, P?=?0.036). The G allele of rs11887092 increased the risk of stroke recurrence in patients with atherothrombotic stroke (adjusted HR 1.59, 95 % CI 1.04–2.44, P?=?0.035). In conclusion, variants of COL3A1 might play a vital role in determining the risk of recurrence and prognosis after stroke. 相似文献
54.
Extramedullary multiple myeloma (EMM) involving the liver as a focal space‐occupying lesion is very rare, especially in the patients with cirrhosis. Here, we report a case of EMM in the liver and periportal lymph node, diagnosed by endoscopic ultrasound guided‐fine‐needle aspiration (EUS‐FNA). A 57‐year‐old male patient, with history of cirrhosis, presented with abdominal pain and pancytopenia. The abdominal magnetic resonance imaging (MRI) demonstrated a 6.5 cm left hepatic mass with a 1.1 cm malignant‐appearing periportal lymph node and diffuse osseous lesions. The cytology specimens from the hepatic mass and the periportal lymph node were obtained through EUS‐FNA without rapid on‐site evaluation (ROSE). The thin‐layer preparations (ThinPrep) showed abundant plasmacytoid cells, which were confirmed to be Kappa‐restricted neoplastic plasma cells by the cell block preparations. Later, his serum level of Kappa light chain was found significantly elevated by flow cytometry, which was identified as monoclonal IgA Kappa light chain by serum protein electrophoresis (SPEP) with immunofixation. The patient was diagnosed as IgA multiple myeloma with extramedullary involvement of the liver and periportal lymph node. This is the first case showing the ThinPrep cytomorphologic features of EMM in the liver and periportal lymph node. This case highlights the importance of distinguishing plasma cells from being hepatocytes and lymphocytes on the ThinPrep and also emphasizes the utility of the cell block in the diagnosis of plasma cell neoplasm. 相似文献
55.
Yingshan Ma Suyue Fu Yichang Zhao Chunjiao Liu Leipeng Li Zhijun Wang Hao Suo Dawei Wang Jinxin Zhao Panlai Li 《RSC advances》2021,12(1):420
A series of Sr3(PO4)2:Ce3+/Mn2+/Tb3+ phosphors were synthesized by a high temperature solid phase method. After introducing Ce3+ as sensitizer in Sr3(PO4)2:Ce3+/Mn2+, the efficient energy transfer from Ce3+ to Mn2+ was observed and analyzed in detail, and Sr3(PO4)2:Ce3+/Mn2+ was demonstrated to be color tunable, changing from blue to orange red. In addition, Tb3+ ion, which mainly emits green light, was further added into the Sr3(PO4)2:Ce3+/Mn2+. Due to the addition of this green emission, the white emitting phosphors with good quality were obtained. At the same time, the energy transfer mechanisms among Ce3+, Tb3+ and Mn2+ ions were also analyzed in detail. The results show that Sr3(PO4)2:Ce3+/Mn2+/Tb3+ is a promising candidate for white light emitting diodes.The tunable emission phosphor was realized by the energy transfer. 相似文献
56.
57.
Many efforts have been devoted to screening new solid-state forms of poorly soluble drugs in the pharmaceutical industry, thus modulating the drug properties without changing the pharmacological nature. It is a wise strategy to prepare amorphous series with cyclodextrin (CD) and its derivatives as excipients to enhance the aqueous solubility, dissolution, and bioavailability of water-insoluble drugs. In this study, four binary amorphous mixtures of ulipristal acetate (UPA) with CDs (β-CD, γ-CD, dimethyl-β-CD, hydroxypropyl-β-CD) were prepared by the co-milling method and characterized in the solid-state. According to powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC), UPA existed in the noncrystalline form in the four binary amorphous mixtures. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) indicated that UPA interacted with the four CDs, which was also verified by molecular docking. Compared with the crystalline and amorphous UPA, the solubility, dissolution, and stability of the drug in the four amorphous UPA systems were significantly improved, so they were considered potentially advantageous solid forms. Our research shows that CDs can be used as new effective excipients in amorphous systems for active pharmaceutical ingredients (API).Probing into the amorphous mixtures of ulipristal acetate and cyclodextrins. 相似文献
58.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献
59.
目的:观察解毒通络方对脑缺血大鼠恢复期海马与皮质中单胺类递质和乙酰胆碱含量的影响。方法:实验于2005-05/2006-02在北京中医药大学病理实验室与中国中医科学院西苑中医院药理实验室完成。选择健康SD大鼠150只,采用双侧颈总动脉夹闭结合低血压状态制作脑缺血模型,将造模成功的150只大鼠随机数字表法分为5组,正常组、模型组及解毒通络方低剂量组、中剂量组、高剂量组,各30只。每组又分为造模后4,8周2个时相点,每个时相点15只。各剂量治疗组每天按不同剂量灌服解毒通络口服液(由栀子、丹参、黄芪、天麻等组成),低、中、高剂量分别相当于生药1.85,3.7,7.4g/kg,配置成给药体积为5mL/kg的溶液;模型组、正常组同时灌胃相应体积的洁净水。以改进的柱前、柱后双酶柱结合高效液相电化学方法检测大鼠海马与皮质的乙酰胆碱含量;以高效液相电化学方法检测大鼠海马与皮质的单胺类神经递质及其代谢产物的含量。结果:纳入动物150只,均进入结果分析。①脑缺血后4周模型组大鼠海马去甲肾上腺素水平与正常组比较显著升高[分别为(797.29±60.04),(528.90±149.13)μg/L,P<0.01]、乙酰胆碱水平显著降低[分别为(19.72±10.09),(39.73±22.31)μg/L,P<0.01],皮质去甲肾上腺素、高香草酸水平与正常组比较显著降低[分别为(52.81±21.71),(258.65±125.82)μg/L,P<0.01;(5.22±3.19),(9.02±2.27)μg/L,P<0.05],海马与皮质多巴胺、5-羟色胺及其他代谢物及皮质乙酰胆碱水平均无明显变化。②脑缺血后8周模型组大鼠海马去甲肾上腺素、多巴胺水平与正常组比较显著升高[分别为(346.88±125.98),(110.76±18.56)μg/L,P<0.05;(7.16±3.52),(3.78±0.44)μg/L,P<0.01],5-羟色胺、乙酰胆碱水平显著降低[分别为(79.38±26.47),(127.64±23.03)μg/L,P<0.01;(14.75±5.21),(22.59±6.58)μg/L,P<0.05],皮质去甲肾上腺素水平也显著降低[分别为(57.67±18.30),(133.43±39.15)μg/L,P<0.01],皮质单胺类递质代谢产物及乙酰胆碱水平则无明显变化。解毒通络方可使上述各项指标的绝大部分恢复到接近正常大鼠水平。结论:解毒通络方能够有效促进脑缺血大鼠海马与皮质中单胺类递质和乙酰胆碱代谢紊乱状态的恢复。 相似文献
60.
目的 对北京市实施2剂次水痘疫苗免疫策略后发生的一起小学水痘暴发疫情开展调查,分析导致疫情发生的预防接种相关因素.方法 采用回顾性队列研究方法,利用传染病网络直报系统和疫情期间主动监测系统发现水痘病例,回顾调查全校学生水痘患病史和水痘疫苗免疫史,比较不同免疫史学生的罹患率.结果 总罹患率为2.3%(30/1282),其中0剂次组罹患率5.9%(1/17),1剂次组罹患率4.2%(22/527),2剂次组罹患率0.9%(7/738).总体疫苗接种率为98.7%(1265/1282),其中1剂次接种率41.1%(527/1282),2剂次接种率57.6%(738/1282).1剂次组发病风险是2剂次组的4.5倍,差异有统计学意义(x2=14.285,P<0.01),2剂次比1剂次增加77.3%的保护率;2剂次组中接种时间间隔<3年的罹患率为0,间隔4至5年的罹患率为0.9%,间隔≥6年的罹患率为2.7%(x2趋势=6.762,P=0.013).结论 2剂次水痘疫苗保护率较1剂次显著提高.2剂次疫苗长期保护效果仍需进一步定量评价. 相似文献