人p75NTR荧光真核表达载体的构建及其在HEK293细胞中的表达

构建了人p75神经营养素受体（p75 neurotrophin receptor,p75NTR）cDNA序列的绿色荧光真核表达载体,并鉴定其在人胚肾293（human embryo kidney293,HEK293）细胞中的表达．采用PCR方法从含人p75NTR的pDC316-HP75质粒中扩增目的片段,经EcoRI和SalI双酶切,定向克隆于pEGFP-N1质粒中,构建绿色荧光真核表达载体pEGFP-N1-HP75,经酶切及测序鉴定后,通过脂质体转染HEK293细胞,激光共聚焦及Western blot法鉴定人p75NTR的表达．结果表明,酶切鉴定和序列分析证实重组质粒含有人p75NTR编码序列,转染实验表明,重组质粒能够在HEK293细胞中表达出具有活性的人p75NTR片段．     

应用误吸风险评估及饮食分级护理预防听神经瘤术后误吸

目的：探讨饮食分级护理和预防听神经瘤术后患者进食误吸的护理效果。方法将100例听神经瘤术后患者按入院时间排序分为干预组（2015年7~12月,50例）和对照组（2015年1~6月,50例）。对照组按照常规护理,干预组术后采用吞误吸风险等级划分,并在此基础上根据误吸风险等级实施饮食分级护理。比较两组患者干预期间进食时误吸发生情况。结果在干预前,两组术后误吸风险比较,差异无统计学意义（P﹥0.05）。干预后,对照组共发生误吸20次,误吸发生率为5.60％,其中呛咳18次,噎食3次,窒息1次;干预组共发生误吸8次,误吸发生率为0.94％,其中呛咳5次,噎食2次,无窒息发生。两组误吸发生率比较差异有统计学意义（ P＜0.01）。结论对听神经瘤术后患者行误吸风险分级,并实施相应的饮食分级护理措施,可有效降低误吸风险,。     

DSC的超光谱图像无损压缩算法

有效的星载超光谱图像压缩技术对于解决超光谱图像实时传输极为重要。针对超光谱图像传统的联合编解码算法的不足,提出了一种基于分布式信源编码(Distributed Source Coding,DSC)的超光谱图像无损压缩算法。为利用超光谱图像的局部空间相关性,将超光谱图像进行分块处理;引入多元线性回归模型构建编码块的边信息,并为每个编码块选取最优的预测阶数,以有效利用超光谱图像的局部谱间相关性。根据(n,k)线性分组码的原理,通过多元陪集码实现超光谱图像的分布式无损压缩。实验结果表明:该算法能够取得较好的无损压缩性能,同时具有较低的编码复杂度,适合星载超光谱图像的压缩实现。     

Mitochondria‐Targeted Small‐Molecule Fluorophores for Dual Modal Cancer Phototherapy

Mitochondria are recognized as the ideal target for cancer treatment because they play a central role in oxidative metabolism and apoptosis. In this work, a mitochondria‐targeted near‐infrared (NIR) photosensitizer (PS) for synchronous cancer photodynamic therapy (PDT) and photothermal therapy (PTT) is synthesized. This multifunctional small‐molecule PS is developed from a variety of synthesized heptamethine cyanine dyes, which are modified with various N‐alkyl side chains on the lipophilic cationic heptamethine core. It is demonstrated to preferentially accumulate in cancer cells by organic‐anion transporting polypeptide mediated active transport and retain in mitochondria by its lipophilic cationic property. As mitochondria are susceptible to hyperthermia and excessive reactive oxygen species, this new PS integrating PTT and PDT treatment exhibits highly efficient phototherapy in multiple cancer cells and animal xenograft models. Furthermore, this targeted PS with NIR imaging property also enables tumors and their margins clearly visualized, providing the potential for precisely imaging‐guided phototherapy and treatment monitoring. This is the first report that a small‐molecule PS integrates both cancer PTT and PDT treatment by targeting mitochondria, significantly increasing the photosensitization. This work may also present a practicable strategy to develop small‐molecule‐based cancer theranostic agents for simultaneous cancer targeting, imaging, and therapy.     

维生素E对大鼠残肾纤维化的抑制作用

目的 观察维生素E对慢性肾衰残肾组织进行性纤维化的抑制作用。方法 在5/6肾切除大鼠慢性肾衰模型上, 以假手术大鼠为对照, 采用形态计量和生化测定方法, 对比分析术后30、60、90、120 天给予或不给予维生素E 治疗的慢性肾衰大鼠残肾纤维化程度。结果 大鼠行5/6 肾切除术后, 在残存肾小球代偿性肥大、肾小球毛细血管代偿性增生的同时, 肾小球显著硬化, 滤过膜显著增厚, 肾间质显著纤维化, 肾组织羟脯氨酸含量显著增高;而用维生素E 治疗的大鼠, 肾小球硬化、滤过膜增厚、肾间质纤维化和肾组织羟脯氨酸含量增高的程度显著减轻, 肾小球代偿性肥大和肾小球毛细血管代偿性增生的发生时间后移。结论 维生素E 能显著抑制5/6 肾切除所致慢性肾衰残肾组织的纤维化, 对其代偿性肾小球肥大和毛细血管增生无明显直接影响。     

雌二醇对大鼠颈动脉球囊损伤后血管平滑肌细胞增殖和内皮功能的影响

目的 研究雌二醇对血管内皮损伤后血管壁细胞增生和内皮功能恢复的作用。方法 应用球囊导管剥脱大鼠的左颈总动脉,于术前六天和术后两周给予17-β雌二醇,通过形态学分析和免疫组化测定血管内膜增生和血管平滑肌细胞增殖程度,并测定乙酰胆碱诱导的内皮依赖性血管舒张反应。结果 17-β雌二醇显著抑制血管内皮损伤后平滑肌细胞增殖和减少新生内膜面积。内皮损伤后乙酰胆碱诱导的血管舒张反应显著降低,最大为12%±6%;雌二醇能使其显著改善,最大舒张反应为48%±9%(P<0.05)。结论 雌二醇显著抑制血管内皮损伤后平滑肌细胞增殖和促进内皮功能的恢复。     

Building a database feedback system

Previous research has shown that user accuracy in database retrievals can be greatly improved by the provision of a conceptual level interface. However, there are still certain queries that are quite difficult. This calls for a feedback system which can provide feedback, regarding the system's interpretation of the query, to further enhance the user's accuracy, with the ultimate goal of 100% accuracy. This paper describes the design and implementation of a database feedback system on top of MERM, a Modified Entity-Relationship Model based DBMS. Specifically, the database feedback system performs the following functions:—it provides English translation of the query;—it shows syntax errors and suggests possible solutions to rephrase a syntactically wrong query; and—it shows likely semantic errors and suggests possible solutions.The results of a laboratory experiment which studies the effects of the database feedback system on user's performance is also reported in this paper.     

Voltage Instabilities Subsequent to Short-circuit Recoveries

A new phenomenon of transient voltage instability in the form of rapid system voltage collapse is detected following short-circuit recoveries at certain load demands and compositions for certain fault durations. Critical clearing times which lead to voltage and load instabilities are determined. Other factors which contribute to the detected new phenomenon are investigated.     

重庆市药物临床试验机构现状分析及地区性机构体系构建的思考

目的：重庆市具有丰富的医药产业底蕴和极佳的医疗资源,在我国药品注册审评制度改革紧密推进和重庆市大力发展生物医药产业的大背景下,本课题从对重庆市药物临床试验机构（以下简称机构）管理人员调研的角度入手,旨在明确重庆市机构建设现状与问题,探讨可行的创新发展对策。方法：本研究对我市20家有药物临床试验资质机构的54位管理人员问卷数据进行统计;并通过比对相应的公共数据,系统分析我市机构建设水平。结果：问卷分析显示,我市机构仍以传统GCP架构模式为主;以承担国内企业项目为主（90.00%）,65.00%的机构近三年承接项目总数在40项以下;机构管理者多数从事机构相关工作的工作年限多在6年以内（79.59%）,且仍有部分机构管理者未接受系统的培训;对公共数据调查分析显示,截至2019年5月底,我市机构总数目为22家,自2017年7月22日以来承接在Clinical Trails注册的在研项目数为81项,远低于机构工作开展较好的城市（北京：61家,433项;上海：53家,326项）。结论：重庆市机构建设水平亟待提高,应整合全市临床研究资源,构建区域化的药物临床试验机构体系,加速重庆市医药产业的创新发展。