Lichtenstein平片无张力疝修补手术228例临床体会

目的：总结Lichtenstein平片无张力疝修补手术治疗成人腹股沟疝的经验。方法：应用聚丙烯网片对228例成人腹股沟疝行Lichtenstein平片无张力疝修补手术。结果：手术平均时间52.5 min,术后住院平均时间5.3 d,全组患者伤口一期愈合,随访期间无复发。结论：Lichtenstein平片无张力疝修补手术治疗成人腹股沟疝安全有效,具有复发率低、并发症少和恢复快等优点。     

Polypropylene vs silicone Ahmed valve with adjunctive mitomycin C in paediatric age group: a prospective controlled study

Purpose

To compare the results of silicone and polypropylene Ahmed glaucoma valves (AGV) implanted during the first 10 years of life.

Methods

A prospective study was performed on 50 eyes of 33 patients with paediatric glaucoma. Eyes were matched to either polypropylene or silicone AGV. In eyes with bilateral glaucoma, one eye was implanted with polypropylene and the other eye was implanted with silicone AGV.

Results

Fifty eyes of 33 children were reviewed. Twenty five eyes received a polypropylene valve, and 25 eyes received a silicone valve. Eyes implanted with silicone valves achieved a significantly lower intraocular pressure (IOP) compared with the polypropylene group at 6 months, 1 year, and 2 years postoperatively. The average survival time was significantly longer (P=0.001 by the log-rank test) for the silicone group than for the polypropylene group and the cumulative probability of survival by the log-rank test at the end of the second year was 80% (SE: 8.0, 95% confidence interval (CI): 64–96%) in the silicone group and 56% (SE: 9.8, 95% CI: 40–90%) in the polypropylene group. The difference in the number of postoperative interventions and complications between both groups was statistically insignificant.

Conclusion

Silicone AGVs can achieve better IOP control, and longer survival with less antiglaucoma drops compared with polypropylene valves in children younger than 10 years.     

Visualization of Thermo‐Oxidative Degradation of Polyolefins in Solution Using HT‐SEC and HT‐AF4‐MALS

The molar mass distributions of high‐molar‐mass PE and PP were characterized using HT‐AF4 and HT‐SEC in combination with IR and MALS detection. Calculated molar mass distributions, average molar masses and radii of gyration were compared. It was found that HT‐AF4 can detect the real extent of thermo‐oxidative degradation during dissolution. HT‐SEC is affected by shear and thermo‐oxidative degradation while in HT‐AF4 no shear stress exists. As a consequence, the molar mass averages obtained from HT‐SEC are pronouncedly lower as obtained from HT‐AF4. In addition, branched polyolefins cannot be correctly characterized by SEC‐MALS due to abnormal co‐elution effects. HT‐AF4 is therefore the method of choice for studying the thermo‐oxidative degradation of macromolecules with high molar masses.

     

HPLC法测定聚丙烯输液瓶中抗氧剂1010、抗氧剂1076、抗氧剂168、抗氧剂330的含量

目的:建立聚丙烯输液瓶中抗氧剂1010、抗氧剂330、抗氧剂1076、抗氧剂168的含量测定方法。方法:采用Venusil MPC18色谱柱(5μm,250 mm×4.6 mm);流动相:甲醇(100%);流速1.0 mL.min-1;柱温25℃;检测波长为274 nm。结果:抗氧剂1010、抗氧剂330、抗氧剂1076、抗氧剂168分别在0.1029～5.145 mg.mL-1、0.1065～5.325 mg.mL-1、0.1034～5.147 mg.mL-1和0.1040～5.200 mg.mL-1范围内线性关系良好,相关系数均为0.999。聚丙烯输液瓶提取方法中的抗氧剂1010、抗氧剂330、抗氧剂1076、抗氧剂168的平均回收率(n=9)分别为101.8%(RSD=1.6%),99.4%(RSD=1.5%)、88.5%(RSD=4.5%)及86.5%(RSD=5.3%)。结论:该方法灵敏快速,操作简便,重复性好,可用于聚丙烯输液瓶中抗氧剂的质量控制。     

双开式聚丙烯输液瓶加药后瓶口不压碘附棉球的探讨

目的探讨双开式聚丙烯塑料输液瓶加药后不压碘附棉球的可行性。方法取聚丙烯塑料瓶装250 ml的无菌氯化钠注射液200瓶分为5组,每组40瓶,均在符合卫生部规定的Ⅲ级区空气细菌标准的环境中,由同一人分别在10、20、30、40、50 min的不同时段加药操作后,对瓶口及瓶内液体进行取样送细菌培养,每组每个时间段各送检20个样本,观察各时间段细菌的生长情况。结果 10、20 min的时间段无菌生理盐水瓶口无细菌生长,30、40、50 min时间段有细菌生长,主要为G杆菌、微球菌、类酵母样菌、凝固酶阴性葡萄球菌,而配药后瓶内液体各个时间段均无细菌生长。表明不同时间段的瓶口被细菌污染数及各瓶口细菌污染菌落计数,以及配药后瓶口和瓶内液体的菌落数,经检验,差异有统计学意义(P<0.05)。结论在符合空气细菌标准条件下进行输液加药操作,双开式聚丙烯输液瓶加药后瓶口不必再压碘附棉球。     

Stability of cefazolin sodium in polypropylene syringes and polyvinylchloride minibags

Background:

Cefazolin is a semisynthetic penicillin derivative with a narrow spectrum of activity covering some gram-positive organisms and a few gram-negative aerobic bacteria.

Objective:

To determine the physical and chemical stability of cefazolin sodium reconstituted with sterile water for injection and stored in polypropylene syringes or diluted with either 5% dextrose in water (D5W) or 0.9% sodium chloride (normal saline [NS]) and stored in polyvinylchloride (PVC) minibags.

Methods:

Reconstituted solutions of cefazolin (100 or 200 mg/mL) were packaged in polypropylene syringes. More dilute solutions (20 or 40 mg/mL) were prepared in D5W or NS and packaged in PVC minibags. For each concentration–diluent–container combination, 3 containers were designated for each day of analysis (days 7, 14, 21, and 30). Containers were stored under refrigeration (5°C) with protection from light until the designated day of analysis, at which time one 5-mL sample was collected from each the designated container. The designated containers were then stored at room temperature (21°C to 25°C) with exposure to light for an additional 72 h, and additional samples were drawn. The samples were assayed using a validated, stability-indicating high-performance liquid chromatography method. The colour and clarity of the solutions, as well as their pH, were also monitored on each sampling day.

Results:

All samples remained clear for the duration of the study; they had a slight yellow colour that darkened over time, and there was an increase in pH. Solutions diluted with sterile water for injection and stored in polypropylene syringes retained at least 94.5% of the initial concentration after 30 days of refrigerated storage and at least 92.1% after an additional 72 h at room temperature with exposure to light. Samples diluted in D5W or NS and stored in PVC minibags retained at least 95.8% of the initial concentration after 30 days of refrigerated storage and at least 91.8% after an additional 72 h at room temperature with exposure to light.

Conclusions:

Cefazolin at various concentrations stored in polypropylene syringes or PVC minibags was stable for up to 30 days with storage at 5°C with protection from light, followed by an additional 72 h at 21°C to 25°C with exposure to light.     

Modification of Laser Marking Ability and Properties of Polypropylene Using Silica Waste as a Filler

Polypropylene (PP) belongs to the group of polymers characterized by low susceptibility to absorption of electromagnetic radiation in the infrared range (λ = 1064 nm). This research consisted of assessing the possibility of using silica waste from the metallurgic industry as an additive for PP laser marking. The modifier was introduced into the polymer matrix in the range from 1 to 10 wt%. The effects of laser radiation were assessed based on colorimetric tests and microscopic surface analysis. The mechanical properties of the composites were determined during the static tensile tests. The thermal properties were investigated via differential scanning calorimetry. It was found that the introduction of silica waste into polypropylene allows for the effective marking of sample surfaces with the use of a laser beam. The greatest contrast between the graphic symbol and the background was obtained for silica contents of 3 and 5 wt%, with the use of a low-speed laser head and a strong concentration of the laser beam. The application of silica caused an increase in the modulus of elasticity and the tensile strength of the composite samples. Increases in the crystallization temperature and the degree of crystallinity of the polymer matrix were also observed. It was found that silica waste can act as multifunctional additive for polypropylene.     

The Friction of Structurally Modified Isotactic Polypropylene

The purpose of studies was to analyse an impact of heterogeneous nucleation of modified isotactic polypropylene (iPP) on its tribological properties. The iPP injection molded samples, produced by mold temperature of 20 and 70 °C, were modified with compositions of two nucleating agents (NA’s), DMDBS creating α-form and mixture of pimelic acid with calcium stearate (PACS) forming β–phase of iPP, with a total content 0.2 wt.% of NA’s. A polymorphic character of iPP, with both, monoclinic (α) and pseudo-hexagonal (β) crystalline structures, depending on the NA’s ratio, was verified. The morphology observation, DSC, hardness and tribological measurements as test in reciprocating motion with “pin on flat” method, were realized, followed by microscopic observation (confocal and SEM) of the friction patch track. It was found that Shore hardness rises along with DMBDS content, independent on mold temperature. The friction coefficient (COF) depends on NA’s content and forming temperature—for upper mold temperature (70 °C), its value is higher and more divergently related to NA’s composition, what is not the case by 20 °C mold temperature. The height of friction scratches and the width of patch tracks due to its plastic deformation, as detected by confocal microscopy, are related to heterogeneous nucleation modified structure of iPP.