铸造牙间卡用于可摘局部义齿修复

目的:改善铸造可摘局部义齿固位体的美观性,减轻颊侧固位体的异物感。方法:在两基牙间的颊、龈外展隙内设置牙间卡(发夹卡)。结果:固位体金属外露少、隐蔽性好,美观明显改善,同时,体积小,无异物感。对34例不同牙缺失患者的使用,经1~2年观察,修复体固位良好,基牙未见松动和移位。结论:铸造牙间卡在美观、制作和异物感等方面明显优于常规铸造冠外固位体。     

Electrical Contact Performance of Cu Alloy under Vibration Condition and Acetal Glue Environment

In view of the serious sliding electrical contact performance caused by external vibration and environmental contaminant, a study on the tribological characteristic and contact resistance of Cu alloy was conducted using a self-developed micro-load reciprocating electric contact device. Various glue concentrations (0%, 10%, 30%, and 50%) were prepared with anhydrous ethanol and deposited on the surface of a pure copper block via the deposition method. An external vibration source was installed on the sliding module to achieve vertical vibration. The results indicate that the final contact resistance and coefficient of friction (COF) in direct metal contact are about 0.01 Ω and 0.3, respectively. At this time, the wear volume is 2 to 3 orders of magnitude higher than the condition with glue residual. As glue concentration is above 10%, residual glue on the surface of Cu alloy hinders efficient contact between friction pairs, resulting in higher contact resistance. Glue exhibits lubrication, anti-wear, and insulation properties. External vibration causes friction pairs to briefly separate, leading to a lower glue removal capacity than that under non-vibration conditions. The contact resistance with glue addition under vibration conditions is higher than that under non-vibration conditions at 3 × 10⁴ cycles. The dominant oxide product is CuO, which has a limited effect on contact resistance.     

TrFIA乙肝病毒PreS1抗原的应用研究

目的:乙型肝炎病毒PreS1抗原时间分辨荧光免疫分析(TrFIA)的应用.方法:收集120例HBVDNA拷贝数＞103的乙型肝炎患者血清标本,同时应用TrFIA和酶联免疫吸附法(ELISA)对样本中PreS1抗原进行检测.选择荧光值较高的一例PreS1抗原阳性血清标本,倍比稀释至1:16384倍,用TrFIA试剂与ELISA定性试剂盒同时进行PreS1抗原的检测.结果:有9例标本ELISA结果为阴性,而用TrFIA可检测到PreS1抗原,χ2=7.1,P＜0.05,TrFIA方法灵敏度高于ELISA方法.一例PreS1抗原阳性血清标本ELISA在1:2048倍时结果为阴性,而TrFIA在1:8192倍时仍可检出PreS1抗原.TrFIA方法高、中、低三个浓度批内CV分别为3.57%、3.71%、6.74%;批间CV分别为3.54%、4.16%、8.52%均优于ELISA方法.50份正常体检者血清标本(乙肝标志物均阴性)用TrFIA试剂进行PreS1抗原的检测,结果均阴性,特异性100%.结论:TrFIA与ELISA相比,精密度和灵敏度有较大提高.     

移植肾肾动脉狭窄的彩色多普勒超声诊断

目的 探讨运用多项彩色多普勒超声（CDUS）指标综合诊断移植肾肾动脉狭窄（TRAS）的的新标准。方法 回顾性分析20例经数字减影血管造影（DSA）证实的TRAS的CDUS指标：移植肾肾动脉收缩期峰值血流速度（PSV）、肾动脉与髂外动脉PSV比值（RIR）、肾动脉与叶间动脉PSV比值（峰值流速后比）和叶间动脉阻力指数（RI）;并与对照组相应指标对比。结果 TRAS组与对照组的上述4项指标之间均存在显著统计学差异（P〈0．001）。新标准具有良好的敏感性（100％）和较高的特异性。结论 新标准能够提高CDUS对TRAS的诊断率。     

An injectable micelle-hydrogel hybrid for localized and prolonged drug delivery in the management of renal fibrosis

Localized delivery, comparing to systemic drug administration, offers a unique alternative to enhance efficacy, lower dosage, and minimize systemic tissue toxicity by releasing therapeutics locally and specifically to the site of interests. Herein, a localized drug delivery platform (“plum‒pudding” structure) with controlled release and long-acting features is developed through an injectable hydrogel (“pudding”) crosslinked via self-assembled triblock polymeric micelles (“plum”) to help reduce renal interstitial fibrosis. This strategy achieves controlled and prolonged release of model therapeutics in the kidney for up to three weeks in mice. Following a single injection, local treatments containing either anti-inflammatory small molecule celastrol or anti-TGFβ antibody effectively minimize inflammation while alleviating fibrosis via inhibiting NF-κB signaling pathway or neutralizing TGF-β1 locally. Importantly, the micelle-hydrogel hybrid based localized therapy shows enhanced efficacy without local or systemic toxicity, which may represent a clinically relevant delivery platform in the management of renal interstitial fibrosis.KEY WORDS: Hydrogel, “Plum‒pudding” structure, Localized therapy, Controlled release, Renal fibrosis, Inflammation, Celastrol, Anti-TGFβ antibody     

移动CT监测肺不张的临床应用

目的应用电子计算机体层摄影(CT)观察全身麻醉诱导前后肺不张的变化。方法8例择期行神经外科手术的患者,于麻醉前、麻醉诱导插管后行全肺CT扫描,选择肺尖、肺门、右膈顶上1cm三个层面的CT图像分析观察肺不张的变化。结果三个层面中,右膈顶上1cm层面的图像麻醉前后变化最明显,麻醉诱导插管后监测到明显的肺不张。结论全麻导致患者肺不张的面积和百分比增加,围术期肺部CT扫描能有效地监测到肺不张的发生,有助于优化术中机械通气,减少肺损伤。     

Rational Design of Waterborne Polyurethane Pressure Sensitive Adhesives for Different Working Temperatures

The appropriate pressure sensitive adhesion performances at working temperature are vital for the applications of waterborne polyurethane (WPU). Understanding the relationship among rheological behaviors, macromolecular structures and adhesive performances can be very useful to the rational design of waterborne polyurethane pressure sensitive adhesives (WPU-PSAs) for different operating temperatures, as well as other kinds of adhesives. In this study, four kinds of WPU-PSAs were prepared by reacting polypropylene glycol (PPG), hydrogenated hydroxyl-terminated polybutadiene (HHTPB), dimethyl alcohol propionic acid (DMPA), 1,6-hexamethylene diisocyanate (HDI) and four kinds of chain extenders. Gel permeation chromatography (GPC), swelling and rheology tests were used in parallel with an analysis of adhesive performances of the dried films of the adhesives. Results showed that, in addition to the nature of chain extenders playing a role on the rheological behaviors and adhesive performances of polymer, the gel content could be used to adjust the macromolecular structure and molecular weight distribution of polymer, thus distinctly affected the adhesive performances of PSA. The relationship among rheological behaviors, macromolecular structure and adhesive performances was investigated, and the rational design of WPU was achieved with appropriate pressure sensitive adhesion properties for different working temperatures of 25 and 60 °C.     

Nucleic acid‐based non‐invasive prenatal diagnosis of genetic skin diseases: are we ready?

The discovery of circulating fetal nucleic acids is a great step on the way of developing non‐invasive prenatal diagnosis (NIPD) for genetic disorders. Here, we briefly discuss the current applications of circulating fetal nucleic acids in genetic testing for different kinds of hereditary diseases with an emphasis on using circulating cell‐free fetal DNA in diagnosis of monogenic disorders. As the genetic skin disorders impair the quality of life at different levels, we next discuss some ethical issues in NIPD for genetic skin diseases of various severities and in particular, the responsibility of doctors and parents, respectively, in the prenatal genetic testing.     

Antimicrobial resistance,presence of integrons and biofilm formation of Salmonella Pullorum isolates from eastern China (1962–2010)

Three hundred and thirty-seven isolates of Salmonella Pullorum from eastern China between 1962 and 2010 were characterized for antimicrobial susceptibility (disk diffusion method), the presence of integrons (polymerase chain reaction followed by sequencing) and the ability to form biofilms (semi-quantitative adherence assay). Two hundred and fifty-eight isolates (76.6%) exhibited multiple drug resistance (MDR; resistant to at least three different classes of antimicrobials), and the level of drug resistance is increasing with time. There were three isolates (9.4%) exhibiting MDR from 1962 to 1968. MDR rates began to increase for isolates between 1970 to 1979 and 1980 to 1987 (64.6 to 78.7%). The MDR rates reached 96.6% for isolates between 1990 and 2010. Polymerase chain reaction screening for integrons showed that 75 isolates (22.3%) were positive for class 1 integrons while none were positive for class 2 integrons. All of the class 1 integron-positive isolates exhibited MDR and were more frequently resistant than the negative isolates. Two hundred and twenty isolates (65.3%) had the ability to form biofilms, and bacterial resistance levels to cefamandole, trimethoprim and trimethoprim/sulfamethoxazole were significantly higher for biofilm-positive groups than the biofilm-negative groups. Our data show that multidrug resistance is common among S. Pullorum isolated from eastern China, being more frequent after 1990 than before 1990, and the presence of class 1 integrons is associated with multidrug resistance.