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31.
One of the advantages of polyurethane foam-covered prostheses has been that in the first 5 to 10 years after their use, the
amount of capsular contraction was found much less than when similar ``slick' prostheses were used. Another advance was their
fixation to the surrounding tissue thus giving a more natural appearance and movement with the muscles when the arms were
moved in any direction. The formation of a thick capsule also acted as a protection against gel granuloma due to rupture of
the prosthesis and has been thought to be a factor in the lower capsule contraction rate. The greatest disadvantage has been
that its removal was extremely difficult and this has continued up until the technique described in this paper has been introduced. 相似文献
32.
Purpose. To obtained rate constants from weight-averaged (Mw) or z-averaged (Mz) molecular weights for polymers of Schule-Flory distribution and undergoing random scission. These constants were compared with those obtained by parallel 1HNMR studies.
Methods. The hydrolysis of two poly(ortho ester)s were followed by 1HNMR and gel permeation chromatography (GPC).
Results. Equations to convert number-averaged (Mn), Mw and Mz into fraction of backbone remaining (fc) were derived. First-order hydrolytic rate constants of two poly(ortho ester)s; DETOSU-HD and DETOSU-CDM were calculated using these relationships. The rate constants calculated from 1HNMR, Mz and Mw were 0.215, 0.218 and 0.182 hr–1, respectively, for DETOSU-CDM and 0.152, 0.086 and 0.038 hr–l for DETOSU-HD. The large discrepancy in the rates determined by 1HNMR and GPC in the latter case was attributed to that the detector response (refractive index) of the monomers was lower than that of the high molecular weight polymer. The difference is small in the case of DETOSU-CDM, and the rates calculated from GPC data were comparable or nearly identical to that obtained from 1HNMR data.
Conclusions. Although GPC can yield rapid and valuable kinetic data for the degradation of biodegradable polymers, the system, however, must be carefully calibrated to account for the variations in Mark-Houwink coefficients and in the response of the mass detector between the high and low MW polymers. 相似文献
33.
用聚焦层析结合DEAE-Sephadex A-50离子交换层析,从正常人肝浸液中分离得两个精氨酸酶同工酶组分.经聚丙烯酰胺凝胶电泳(PAGE)鉴定从聚焦层析得到的第一峰同工酶组分为一条蛋白带,第二峰具有精氨酸酶活性的蛋白组分的主要蛋白带也极明显。各蛋白质成分向阴极电泳的前后顺序与从聚焦层析洗脱的先后次序一致。两型同工酶的比活力分别约为2050U/mg及790U/mg。用SDS-PAGE检测两型同工酶均由两种亚基组成,且分子量近似。 相似文献
34.
目的 探讨多种形式的健康教育对提高宫颈糜烂治疗依从性的作用。方法 将确诊为宫颈糜烂的120例患者随机分为研究组、对照组。均给予相应的治疗。研究组增加健康教育内容。两组患者同时观察复诊率、治愈率、对医疗服务的满意程度、疾病的认知情况。结果 研究组增加健康教育后,患者复诊率、治愈率、诊疗满意程度、疾病认知情况均较对照组高(P<O.05)。结论 健康教育能提高宫颈糜烂患者的治疗依从性,获得较高的治愈率。 相似文献
35.
隆鼻硅胶假体雕刻中的四个角度 总被引:1,自引:0,他引:1
目的探讨隆鼻硅胶假体雕刻中的四个角度与隆鼻并发症的关系。方法总结了420例硅胶假体隆鼻术患者,分析并发症与假体雕刻的关系,提出假体雕刻要与鼻部解剖形态相吻合的四个角度。结果术后1周,发现3例患者假体鼻根部向一侧轻度偏斜,2例6个月后鼻根部假体固定不良。1例术后主诉头痛,取出假体后症状消失。其余未发生并发症。结论假体雕刻与鼻部解剖形态的四个角度相吻合,可以减少并发症的发生,提高美容效果。 相似文献
36.
目的:了解烧伤病区铜绿假单胞菌(Pseudomonas aeruginosa,PA)感染的分子流行病学特征。方法:采用脉冲场凝胶电泳(PFGE)分型的方法,对15株分离自烧伤临床病人的多重耐药PA染色体组DNA进行分析。结果:15株检测菌株中有9株菌分别属于两种不同的PFGE图谱类型,具有同源性的菌株占测试菌株的60%。结论:导致我院烧伤患者感染多重耐药的PA中有同源性的比例较高,提示在烧伤救治中采取有针对性的措施,防止烧伤病房内的交叉感染对于降低烧伤感染率、提高烧伤救治水平具有重要意义。 相似文献
37.
38.
S. Savi M. Savi S. Tamburi G. Vuleta S. Vesi C.C. Müller-Goymann 《European journal of pharmaceutical sciences》2007,30(5):441-450
There is a growing need for research into new skin- and environment-friendly surfactants. This paper focuses on a natural surfactant of an alkylpolyglucoside type, which can form both thermotropic and lyotropic liquid-crystalline phases. The aim of this study was to relate some physicochemical properties (characterised by polarisation and transmission electron microscopy, thermal analysis and rheology) of the three formulations based on cetearyl glucoside and cetearyl alcohol, to the results of in vitro and in vivo bioavailability of hydrocortisone (HC). The three formulations contained oils of different polarity (medium chain triglycerides: MG, isopropyl myristate: IPM and light liquid paraffin: LP), respectively. In vitro permeation was followed through the artificial skin constructs (ASC), while the parameters measured in vivo were erythema index: EI (using instrumental human skin blanching assay), transepidermal water loss (TEWL) and stratum corneum hydration (SCH). The vehicles based on cetearyl glucoside and cetearyl alcohol showed a complex colloidal structure of lamellar liquid-crystalline and lamellar gel-crystalline type, depending on oil polarity. Rheological profile of the vehicle was directly related to the in vitro profile of the HC permeation. In vivo results suggested that the vehicle with MG retarded the HC permeation, whereas less polar IPM and non-polar LP enhanced it. It is suggested that the enhancement is achieved either by a direct interaction with lipid lamellae of the SC or indirectly by improving skin hydration.
There were no adverse effects during in vivo study, which indicates a good safety profile of this alkylpolyglucoside surfactant. 相似文献
39.
The relationship between high-density-lipoprotein (HDL) particle size subclasses and the levels of the major lipoprotein lipids was studied in 74 men consecutively referred to the lipid clinic. HDL (density 1.070-1.21 kg l-1) was separated by polyacrylamide gradient gel electrophoresis (GGE) into five size-defined subclasses, in order of decreasing size as follows: HDL2b, HDL2a, HDL3a, HDL3b and HDL3c. Cholesterol and triglyceride concentrations in very-low-density (VLDL), low-density (LDL) and high-density (HDL) lipoproteins were determined. The level of VLDL triglycerides was negatively correlated with HDL2b (r = -0.66, P less than 0.0001), and positively correlated with HDL3b concentrations (r = 0.65, P less than 0.0001). Both correlations were restricted to subjects with VLDL triglyceride concentrations of less than 1.80 mmol l-1, i.e. those with normotriglyceridaemia. Patients with a history of myocardial infarction and/or angina pectoris (n = 18) had significantly lower HDL2b levels than subjects with asymptomatic hyperlipidaemia (n = 50), i.e. 0.16 vs. 0.22 mg protein ml-1 (P less than 0.05), despite essentially similar cholesterol and triglyceride levels in the VLDL, LDL and HDL fractions, including HDL2 and HDL3 cholesterol. 相似文献
40.
目的为了初步了解男性精浆中的蛋白电泳谱以及蛋白谱与男性生育能力的相关关系。方法通过应用SPIFE3000全自动电泳分析仪对20例对照组(生育组)与140例观察组(不育组)的精浆进行蛋白分离(琼脂糖区带电泳法),建立其精浆蛋白质的特征电泳图谱,并进行对比分析。结果精浆蛋白经酸蓝染色后,区带清晰,从阳极到阴极分为A、B、C、D、E 5条带,电泳各区带百分比含量结果经方差分析,发现不育组与生育组A、C、D、E百分比含量变化有统计学意义(P<0.01),且无精子症患者精浆的蛋白谱有特异的"双峰"特点。结论精浆蛋白区带电泳分析可作为不育症的辅助诊断指标,且将是对男性不育诊断手段的有力补充。 相似文献