衬套参数对柱塞泵柱塞副油膜特性的影响分析

为改善液压柱塞泵中柱塞副的磨损状况,建立流固耦合模型,求解流体域与固体域的相互作用。考虑柱塞变形和缸体孔衬套变形,讨论不同弹性模量的铜合金衬套材料和不同厚度的衬套对衬套变形和油膜厚度的影响。结果表明,衬套变形值随衬套材料弹性模量增加而减小,采用弹性模量小的铜合金衬套材料或适当增加衬套厚度能使油膜厚度增大,可以改善柱塞副润滑条件,延长柱塞泵的使用寿命。不同弹性模量的铜合金衬套材料和不同厚度的衬套对油膜厚度影响明显。研究结果为柱塞泵的优化设计提供一定的参考。

以药品作用为主的药械组合产品注册法规体系的思考和建议

本文归纳对比了中国、美国、欧盟及日本以药品作用为主的药械组合产品的定义、监管机构、注册审评机制及相关注册法规的差异,并结合我国药械组合产品研发和注册过程中遇到的问题,提出了完善申请人与监管部门的沟通交流、药械组合产品的属性界定、注册申报的技术要求、药械联合审评的协调机制等方面的建议,以期为促进我国以药品作用为主的药械组合产品法规监管体系建设提供参考。

不同节律下心房颤动患者心房低电压区比较及意义

目的探讨不同节律下心房颤动(简称房颤)患者电解剖标测心房低电压区(low voltage areas,LVAs)的特征及意义,并分析单纯肺静脉隔离(pulmonary vein isolation,PVI)术对LVAs的影响。方法连续纳入首次接受射频消融治疗的84例房颤患者,其中49例阵发性房颤,35例持续性房颤,使用倾向性评分进行匹配。在0.5 mV的阈值下测量心房五分区后各区域LVAs的面积并进行分析。结果根据年龄、性别、BMI,采用倾向性评分匹配出31组患者。阵发性房颤患者术前平均标测点数为(1434.2±393.6)个,术后为(1281.3±372.7)个;持续性房颤患者术前平均标测点数为(1652.6±728.2)个,术后为(1314.6±690.8)个。在所有研究对象中,均可记录到LVAs的存在。阵发性房颤患者术前术后LVAs面积比较,差异无统计学意义;持续性房颤患者LVAs面积术后明显下降(P<0.05)。在所有84例房颤患者中,LVAs出现在前壁、间隔、下壁、侧壁和后壁的比例分别为69.0%、95.2%、82.1%、60.7%和52.4%。结论在相同的电压阈值下,持续性房颤患者LVAs面积在房颤节律下明显大于窦性节律下,单纯PVI术对LVAs影响不大。房颤患者中LVAs好发于前壁、间隔及下壁。

药物临床试验伦理审查体系医疗机构管理的现况调查研究

药物临床试验伦理审查体系中的医疗机构管理是受试者保护的重要环节之一。采用调查问卷的方式,收集我国354家医疗机构在药物临床试验伦理审查体系中的管理现况,包括研究项目管理、研究利益冲突管理、合同管理、经费管理、培训管理、质量管理、伦理委员会组建与换届、伦理委员会资源、伦理审查的独立性以及伦理审查的透明性等要素,分析医疗机构履行受试者保护和对伦理委员会规范管理的职责情况并提出相应的建议。

我国药物临床试验伦理审查能力的调查研究

伦理审查能力是药物临床试验伦理委员会建设与管理的核心环节。伦理委员会的审查能力不仅是委员遵循公认的伦理原则对研究方案进行审议和决定的能力,还取决于与伦理委员会审查相关的程序规则。采用调查问卷的方式,采集我国354家药物临床试验机构伦理审查的程序、规则以及质量管理情况,包括审查工具、审查效率、主审、预审、独立顾问、审查、审查会议规则、年度/定期审查、复审管理、委员履职能力考核、质量管理等,分析伦理审查能力并对改进伦理审查能力提出相应的建议。

无射线三维心包穿刺技术的有效性与安全性分析

目的阐释心包穿刺过程中的电学特点并探讨一种不依赖X线的三维心包穿刺新技术的有效性和安全性。方法以健康家猪为实验动物,在三维电解剖标测系统指导下用Smart Touch压力导管三维重建左右心室,随后用Carto Sound超声导管重建心外膜外壳。将心包穿刺针或者导丝设置为一个电极并连接于三维电解剖标测系统,观察三维心包穿刺过程中的空间特点,同时通过针尖上的单极电图,观察三维心包穿刺过程中的电学特点。结果13只实验猪均成功完成了心包穿刺,在三维系统上不仅能够准确显示穿刺针的移动,也能够显示导丝的移动。纵隔电位(3.2±1.1)m V,心包外膜电位(4.8±1.5)m V,心外膜电位(9.6±2.6)m V,两两比较差异均有统计学意义(均P<0.05)。3只实验猪尝试2次或以上穿刺成功,其余均为第1次穿刺成功。8只实验猪短暂使用X线,X线透视时间(43±25)s,5只全程没有使用射线。术中急性心包渗血4只,但均没有心脏压塞表现,术后观察24 h均无心包渗血。结论心外膜、心包以及相邻纵隔的电位变化具有特征性,电学指导下三维心包穿刺不仅安全有效,还是一种不依赖X线的技术。

利用基因表达谱筛选肝细胞癌中炎性微环境形成相关新基因的研究

目的:利用基因表达谱芯片筛选肝细胞癌(HCC)中的差异表达基因,并分析神经降压素(NTS)表达与HCC中炎性微环境形成的相互关系。方法:收集10例原发性HCC癌与癌旁组织,提取RNA进行Affvmetrix全基因组表达谱芯片检测,同时整合GEO数据库中同芯片平台的亚洲人原发性HCC的mRNA表达谱数据30例,利用R2.9.0软件获得差异基因列表,应用Metacore2.5,Pathway studio6.0和Ingenuity1.0软件进行信号通路分析。最后,结合HE染色比较不同NTS表达水平的HCC标本中炎症反应强度。结果:所有RNA样品无降解,各芯片数据的信号强度分布均一。SMA聚类和信号通路分析结果显示40例HCC标本中存在一组独特亚群,呈现神经降压素(NTS)高表达,并伴有胞外间质重构、细胞粘附、白细胞移动、血管新生等生物学过程显著增强。HE染色证实NTS高表达标本中炎细胞浸润、纤维增生和血管生成明显高于NTS低表达的标本。结论:NTS高表达可能促进HCC中炎性环境的形成。

ReVive SE机械取栓对比静脉溶栓治疗中国急性缺血性卒中患者的成本效用分析

目的 :本研究从付费者角度,评价ReVive SE机械取栓对比静脉溶栓治疗中国急性缺血性卒中(AIS)患者的经济性,以期为临床决策提供依据。方法 :基于ReVive SE的前瞻性临床研究和二次文献研究构建经济学模型,模型分为二个阶段,第一个阶段是决策树模型,第二个阶段是马尔科夫模型,模拟AIS后采用机械取栓与静脉溶栓两种治疗方案的疾病进程,并根据预测治疗结果进行成本-效用分析。结果 :从第6年开始,ReVive SE机械取栓组对比静脉溶栓组更具成本效果,整个生命周期两组的增量成本效果比为96,316元/QALY,低于WHO推荐的3倍人均GDP阈值(2016年161,940元)。敏感性分析验证了研究结果的稳健性。结论 :与静脉溶栓相比,ReVive SE机械取栓治疗AIS患者更具卫生经济学优势。

聚酰胺用于选择性激光烧结3D打印截骨导板的性能研究

目的研究一种用于选择性激光烧结3D打印截骨导板的聚酰胺材料的机械、化学性能以及生物相容性。方法机械性能研究包括材料断裂延伸率、拉伸模量、抗拉强度、维卡软化温度、负荷变形温度和磨损质量。化学性能研究包括还原物质、酸碱度、重金属总量、蒸发残渣和紫外吸光度。生物学评价内容包括体外细胞毒性、皮肤致敏和皮内刺激。检测机械性能、化学性能以及生物相容性,并对其结果进行评价。结果机械性能:断裂延伸率为7.8%~22.3%,拉伸模量为1664~1982 MPa,抗拉强度为47.71~51.25 MPa,维卡软化温度为163.2~166.0℃,负荷变形温度为66.2~75.2℃,磨损质量为6.8~16.8 mg。化学性能符合GB19335-2003的要求。生物学评价:对体外细胞无潜在毒性影响,未发现皮肤致敏反应,未发现皮内刺激反应。结论该聚酰胺材料具有良好的机械、化学性能以及生物相容性,可用于生产制造手术3D打印截骨导板。

小型猪肺部三维重建与脉管3D打印模型

目的探讨小型猪肺部三维重建模型建立方法及3D打印模型的应用。方法4头巴马小型猪行全身麻醉做肺部CT血管成像,获取数据采用MIMICS软件重建肺段组织结构,3D打印肺部脉管的实体模型。结果基于CT血管成像数据重建的三维模型,清晰展现小型猪肺部血管和支气管3~4级分支的解剖结构,并显示叶裂和部分段间平面,可任意旋转和缩放。结论利用三维重建和3D打印技术可成功创建巴马小型猪肺部解剖结构模型,为比较医学研究和胸外科手术培训材料提供基础。

A STUDY OF STRUCTURE AND PROPERTY CHANGES OF BIODEGRADABLE POLYGLYCOLIDE AND POLY(GLYCOLIDE-co-LACTIDE)FIBERS DURING PROCESSING AND IN VITRO DEGRADATION

Structure and properties of bioabsorbable polyglycolide (PGA) and poly(glycolide-co-lactide) (PGA-co-PLA)fibers were investigated during several industrial processing stages and in vitro degradation by means of wide-angle X-raydiffraction (WAXD), dynamic mechanical analysis (DMA) and mechanical property tests. In the orientation stage, the PGAfibers were found to have higher degrees of crystallinity than corresponding PGA-co-PLA samples produced under similarconditions. In the hot-stretching and post-annealing stages, after fibers were braided, PGA samples were found to gain morecrystallinity and higher T_g than PGA-co-PLA samples. The higher crystallinity in PGA fibers resulted in a slower rate ofdegradation. DMA results showed that a great deal of internal stress that was built during orientation and hot-stretchingstages was released in the post-annealing stage for a1l PGA and PGA-co-PLA samples. During earlier stages of in vitrodegradation, both PGA and PGA-co-PLA samples exhibited the typical cleavage-induced crystallization mechanism. Theheat shrinkage in the glass transition area was found to disappear after 6-8 days of degradation for all PGA and PGA-co-PLAsamples, indicating the amorphous portions of the polymers lost orientation after a short period in the buffer solution, mostlikely due to relaxation of the cleaved chains.

Challenges and trends in apomorphine drug delivery systems for the treatment of Parkinson's disease

Parkinson's disease(PD) is a chronic debilitating disease affecting approximately 1% of the population over the age of 60. The severity of PD is correlated to the degree of dopaminergic neuronal loss. Apomorphine has a similar chemical structure as the neurotransmitter dopamine and has been used for the treatment of advanced PD patients. In PD patients,apomorphine is normally administered subcutaneously with frequent injections because of the compound's extensive hepatic first-pass metabolism. There is, hence, a large unmet need for alternative administrative routes for apomorphine to improve patient compliance.The present review focuses on the research and development of alternative delivery of apomorphine, aiming to highlight the potential of non-invasive apomorphine therapy in PD,such as sublingual delivery and transdermal delivery.

三维光学相干断层成像飞秒激光辅助白内障手术在真实世界证据研究中的应用

目的:本研究是一项真实世界证据(real-world evidence,RWE)研究,旨在评价在博鳌超级医院实施的3D OCT飞秒激光辅助白内障手术的性能。方法:共纳入139眼(113例患者),其中32眼(28例患者)在手术医师培训和认证期间接受了治疗(手术医师认证人群),107眼(92例受试者)在手术医师得到认证后接受了治疗(分析人群)。使用CATALYS眼科飞秒激光治疗机对单眼或双眼实施了角膜切口、晶状体前囊膜切开术和晶状体粉碎术。结果:99.3%的患者成功完成了囊膜切开术,97.8%的患者成功完成了晶状体粉碎术,90.7%的患者成功完成了角膜切口。术后4周,82.5%术眼的裸眼远视力(uncorrected distance visual acuity,UCDVA)达到20/40或更佳,而术前该比例为17.3%;97.1%术眼的最佳矫正远视力(best corrected distance visual acuity,BCDVA)达到20/40或更佳,而术前该比例为46.8%。在经治疗的139眼中,总计发生了10例手术并发症。结论:本项真实世界证据研究表明,当按照角膜切口、晶状体前囊膜切开术和晶状体粉碎术的适应症使用CATALYS眼科飞秒激光治疗机时,其能够安全且有效地应用于成人患者。

The Electrical Conductive Effect of Nickel-coated Graphite/Two-component Silicone-rubber Sealant

Nickel-coated graphite particles and two-component silicone-rubber were compounded to form a conductive composite system. The electrical volume resistivity of the composites were examined and compared under constant tensile strains, cyclic heating-cooling, electric field and repeated cyclic tensile strains in order to study the mechanism of electrical conductivity behaviors of the conductive composites under stress, temperature and current. The results showed that a peak value of the electrical resistivity appeared previously and then gradually increasing with increasing tensile strain. The electrical resistivity displayed positive temperature coefficient effect during the temperature increasing and decreasing. Applying 5A direct current to the conductive composites lesulted in an increase in the electrical resistance immediately, but no changes were detected under lower currents. Under the repeated cyclic strain, the peak value of the electrical resistivity of each cycle increased with the test cycle. All the electrical resistivity changes were attributed to the conductive networks broken-up and rebuilt in the conductive composites.

DOST Model’ for DR-TB Patients, New Delhi: Perspectives of Healthcare Providers

Introduction: In India, tuberculosis continues to be a major public health problem and there is a growing concern about drug-resistant tuberculosis as most of the patients are from private sector. The National TB Elimination Programme (NTEP) in collaboration with TB Alert, India (TBAI) and Clinton Health Association of India (CHAI) had implemented a collaborative project to strengthen the network between the private practitioners and public healthcare facilities in New Delhi during 2019 and 2020. Methods: A study was conducted to understand the enablers and challenges encountered by them during the implementation of the project. This is a qualitative exploration of the “healthcare providers” on a project linking DR-TB patients in private sector with government health facilities. The process of data collection involved face-to-face in-depth interviews of healthcare providers, the Doctors mainly from private and public health facilities, the paramedical workers from general health system and paramedical from the project using an interview guide administered through a trained researcher. Results: The study findings revealed that all healthcare providers were completely aware of the DOST project in the health system, the model led to early diagnosis and initiation of quality treatment. There were no major challenges to the implementation of the project. The healthcare providers wish to have this project implemented for a longer duration. Conclusion: The perspectives of healthcare providers towards the “DOST” project were optimistic and call for re-initiating the project in the area.

Cosmetic Lifting Effect of a Formula Combining Tetrahydroxypropyl Ethylenediamine, Ononis Spinosa and Glycerin as Shown by a New 2-D Imaging Method

Facial sagging is a major aging change that affects the overall shape of the face. Sagging can negatively impact self-perception and consequently quality of life. In order to fight against this aging sign, we developed a combination of three active ingredients: Tetrahydroxypropyl Ethylenediamine (THPE), Ononis Spinosa extract and Glycerin. In a clinical study, we assessed the efficacy of this association on facial sagging and wrinkles, with a special focus on immediate and lasting effects. Thirty-nine women applied the tested product daily during an eight-week treatment period. Clinical grading by experts and a new, easy to operate, 2-D imaging method were performed at different time points. The 2-D imaging method measured the upper eyelid lifting effect. The results showed an immediate and significant improvement in sagging and wrinkle parameters;these benefits were still observed seven hours after the first application. Results also showed a significant long-term improvement. The lifting effect calculated from the 2-D pictures was 1.08 mm immediately after application;the same method showed a 1.80 mm lifting effect following the eight-week treatment period. These results suggest that a skin care product combining THPE, Ononis Spinosa and Glycerin properties may be used to reduce sagging as well as wrinkles with both immediate and long term benefits.

A Placebo-Controlled Study Demonstrates the Long-Lasting Anti-Aging Benefits of a Cream Containing Retinol, DihydroxyMethylChromone (DMC) and Hyaluronic Acid

Retinol is an ingredient used in cosmetic products for reducing the appearance of the signs of aging and photo-damage. Currently, most of these products contain 0.1% of retinol. However, at this concentration, some irritation can occur. We have evaluated in vitro and in a clinical study the potential efficacy of a combination of actives to improve the facial skin aging signs while using low concentration of retinol. We demonstrated, in vitro, that a chromone derivative, 5,7-di-hydroxy-2-methyl chromone (DMC), is able to enhance the collagen synthesis in culture of normal human dermal fibroblasts. The enhancement of retinol anti-wrinkle efficacy by DMC was confirmed in a small scale clinical trial. Specifically, a product associating low concentration of retinol (0.04%) and DMC (0.1%) in combination with low molecular weight hyaluronic acid fragments (50,000 Dalton of average molecular weight) has been applied topically for 8 weeks. Clinical results show significant improvement of various signs of facial skin aging such as wrinkles, pigmentary spots, tone unevenness, dullness and the overall photo-damage score. Improvements were still visible 4 weeks after the cessation of the test product application. This study demonstrates that significant lasting improvement of facial skin aging can be obtained with well tolerated low concentration of retinol when adequately formulated with other anti-aging ingredients.

上海某医院护理人员肌肉骨骼疾患模式与危险因素

[目的]肌肉骨骼疾患(MSDs)患者同质性的增加可能可以增强治疗的有效性,也有利于MSDs发生机制的探索。本研究拟应用潜在类别分析(LCA)识别上海某医院护理人员MSDs的分类模式,以提高分组对象的同质性,并探讨相关危险因素与模式之间的联系。[方法]运用横断面调查方法,收集护理工作量数据,并结合前期研究问卷数据,包括研究对象个体信息,各部位MSDs患病情况以及职业因素等,运用LCA识别肌肉骨骼疾患模式及相关危险因素。[结果]经潜在类别分析,该医院护理人员MSDs模式最优模型为6分类,分别为:上半身疼痛组(潜在类别概率γ=0.208)、仅腰部疼痛组(γ=0.182)、轻微疼痛组(γ=0.169)、颈肩腰疼痛组(γ=0.152)、各部位均疼痛组(γ=0.152)、上半身及下肢疼痛组(γ=0.138)。职业因素进入模型,发现"休息不足"普遍存在于各类别中(条件概率ρ> 0.7),上半身及下肢疼痛组的所有样本均报告工作中"搬运重物"(ρ=1.000)。以工作量值分组后,最佳拟合结果均为4个分类,轻工作量组分别为仅腰部疼痛组1(γ=0.155)、仅腰部疼痛组2(γ=0.183)、各部位均疼痛组(γ=0.257)、上半身疼痛组(γ=0. 405);中等工作量组分别为颈及踝足疼痛组(γ=0.151)、轻微疼痛组(γ=0.270)、各部位均疼痛组(γ=0.156)、上半身疼痛组(γ=0.422);重工作量组分别为仅腰部疼痛组(γ=0.390)、颈肩腰疼痛组(γ=0.195)、各部位均疼痛组(γ=0.131)、上半身及下肢疼痛组(γ=0.284)。工龄分析中,各分类工龄OR> 1.000,除重工作量组中"颈肩腰疼痛组""上半身疼痛组"外,其余均有统计学意义(P <0.05)。[结论]该医院护理人员MSDs存在一定疼痛模式。护理人员暴露于不同的职业危险因素,将会进入不同MSDs类别中,如常搬运重物的护理人员更易分入上半身及下肢疼痛组。科室工作量不同,护理人员MSDs模式不同。随着工龄增大,护理人员更易出现多部位疼痛模式。

Blocking the Metabolism of Starch Breakdown Products in Arabidopsis Leaves Triggers Chloroplast Degradation

In most plants, a large fraction of photo-assimilated carbon is stored in the chloroplasts during the day as starch and remobilized during the subsequent night to support metabolism. Mutations blocking either starch synthesis or starch breakdown in Arabidopsis thaliana reduce plant growth. Maltose is the major product of starch breakdown exported from the chloroplast at night. The maltose excess 1 mutant （mex1）, which lacks the chloroplast envelope maltose transporter, accumulates high levels of maltose and starch in chloroplasts and develops a distinctive but previously unexplained chlorotic phenotype as leaves mature. The introduction of additional mutations that prevent starch synthesis, or that block maltose production from starch, also prevent chlorosis of mex1. In contrast, introduction of mutations in disproportionating enzyme （DPE1） results in the accumulation of maltotriose in addition to maltose, and greatly increases chlorosis. These data suggest a link between maltose accumulation and chloroplast homeostasis. Microscopic analyses show that the mesophyll cells in chlorotic mex1 leaves have fewer than half the number of chloroplasts than wild-type cells. Transmission electron microscopy reveals autophagy-like chloroplast degradation in both mex1 and the dpe1/mex1 double mutant. Microarray analyses reveal substantial reprogramming of metabolic and cellular processes, suggesting that organellar protein turnover is increased in mex1, though leaf senescence and senescence-related chlorophyll catabolism are not induced. We propose that the accumulation of maltose and malto-oligosaccharides causes chloroplast dysfunction, which may by signaled via a form of retrograde signaling and trigger chloroplast degradation.

An efficient synthesis of substituted benzene-1,2-dicarboxaldehydes

Substituted-benzene-1,2-dicarbaldehydes were synthesized by the reaction of substituted-1,2-bis(dibromomethyl) benzenes with fuming sulfuric acid,followed by hydrolysis. The yields were signifi-cantly improved by introducing solid sodium bicarbonate into the reaction mixture before hydrolysis and workup.