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21.
目的:观察玻璃体切除联合眼内注药或硅油填充术对眼球穿通伤后合并感染性眼内炎不伴视网膜脱离的疗效。 方法:应用经睫状体平坦部玻璃体切除术,以联合眼内注药或硅油填充术分组治疗30只眼球穿通伤并发感染性眼内炎不伴有视网膜脱离患者,术后予以静脉、结膜下及眼药水途径给予抗感染抗炎治疗。 结果:玻璃体切除术后追踪随访3~12个月,2组30只眼细菌性感染全部控制,术后视力较术前视力有显著性提高,联合眼内注药组19只眼,其中4只眼(21.1%)发生视网膜脱离:联合硅油填充组11只眼,其中术后1只眼(9%)发生视网膜脱离。两组术后并发症发生率均无明显差异(P〉0.05)。 结论:玻璃体切除联合硅油填充术能有效控制炎症,稳定视网膜功能,对一些视网膜情况不佳或炎症难以控制的患者可以考虑术中应用硅油。  相似文献   
22.
Objective The aim of this study was to investigate macular perfusion changes and ganglion cell complex(GCC) loss in patients with unexplained visual loss following vitrectomy and silicone oil(SO)tamponade, and to evaluate the correlation between retinal blood flow and GCC loss using optical coherence tomography angiography(OCTA) and optical coherence tomography(OCT).Methods This retrospective study included seven eyes(seven patients) with unexpected visual loss after vitrectomy and SO tamponade. OCTA was used to evaluate the alterations in retinal vessel density(VD) in the superficial capillary plexus(SCP), deep capillary plexus(DCP), and radial peripapillary capillary plexus(RPCP). OCT was used to measure the thickness of GCC and retinal nerve fiber layer(RNFL).Medical records of patients were reviewed.Results Quantitative analysis of OCTA images revealed a significant reduction in SCP VD in the affected eyes compared with the controls(all sections P 0.05). No difference was found in GCC thickness, but FLV(focal loss volume) and GLV(global loss volume) were significantly higher in the affected eyes(both P 0.001). SCP VD was inversely correlated with FLV and GLV.Conclusions Silicone oil-related severe visual loss was associated with superficial retinal microvasculature damage and ganglion cell apoptosis.  相似文献   
23.
Loss of maxillo facial structures due to neoplasm, trauma and accidents gives inconsolable mental, physical and psychological agony to a person’s dignified life in his living society. Surgical reconstruction was not feasible for all cases and certain cases needs prosthetic rehabilitation. In this clinical case report, an innovative, simple three part maxillo orbital prosthesis fabrication using magnets was explained.  相似文献   
24.
Soft denture liners act as a cushion for the denture bearing mucosa through even distribution of functional load, avoiding local stress concentrations and improving retention of dentures there by providing comfort to the patient. The objective of the present study was to compare and evaluate the tensile bond strengths of silicone-based soft lining materials (Ufi Gel P and GC Reline soft) with different surface pre treatments of heat cure PMMA denture base acrylic resin. Stainless steel dies measuring 40 mm in length; 10 mm in width and 10 mm in height (40 × 10 × 10) were machined to prepare standardized for the polymethyl methacrylate resin blocks. Stainless steel dies (spacer for resilient liner) measuring 3 mm thick; 10 mm long and 10 mm wide were prepared as spacers to ensure uniformity of the soft liner being tested. Two types of Addition silicone-based soft lining materials (room temperature polymerised soft lining materials (RTPSLM): Ufi Gel P and GC Reline soft) were selected. Ufi Gel P (VOCO, Germany), GC Reline soft (GC America) are resilient, chairside vinyl polysiloxane denture reliners of two different manufacturers. A total of 80 test samples were prepared of which 40 specimens were prepared for Group A (Ufi Gel P) and 40 specimens for Group B (GC Reline soft). In these groups, based on Pre-treatment of acrylic resin specimens each group was subdivided into four sub groups of 10 samples each. Sub-group I—without any surface treatment. Sub-group II—sand blasted Sub-group III—treated with Methyl Methacrylate monomer Sub-group IV-treated with chemical etchant Acetone. The results were statistically analysed by Kruscal Wallis test, Mann–Whitney U test, and Independent t test. The specimens treated with MMA monomer wetting showed superior and significant bond strength than those obtained by other surface treatments. The samples belonging to subgroups of GC Reline soft exhibit superior tensile bond strength than subgroups of Ufi Gel P. The modes of failure of all specimens were mostly adhesive in nature. Surface pre treatments by chemical means improved the bond strength between the silicone liners and denture base.  相似文献   
25.
Mobile phone usage has been increased in the last few years emitting electromagnetic radiation (EMR), which disturbs normal cellular processes via oxidative stress. L-cysteine, a glutathione precursor, prevents oxidative damage. Transdermal patches (TDPs) loaded with L-cysteine hydrochloride (L-CyS-HCL) were fabricated by dispersion of L-CyS-HCL 5% w/w and different concentrations of sorbitol as a plasticizer in room-temperature vulcanizable synthetic silicone matrices (RTV-Si). The effect of sorbitol on patch physicochemical parameters was assessed; in-vitro L-CyS-HCL release profiles and ex-vivo permeation were studied. Pharmacokinetic parameters of endogenous synthetized in-vivo glutathione, after receiving IV bolus dose of L-CyS-HCl and L-CyS-HCl-RTV-Si-TDPs were studied in rat model. The influence of L-CyS-HCL-RTV-Si-TDPs against damaging effects of mobile phone EMR on rats' blood and brain tissues was studied. The results revealed that patch plasticity, intensity reflections, surface porosity, L-CyS-HCL release rate and skin permeation increased with increasing sorbitol concentration. Pharmacokinetic profile for IV dose and L-CyS-HCl-RTV-Si-TDPs revealed that the L-CyS-HCl-RTV-Si-TDPs provided a sustained glutathione plasma concentration–time profile over entire patch application. High significant differences in biological parameters (blood and brain samples) were observed for radiated rats using the patch in study compared with positive control rats. Promising long-term strategy for protection against mobile phone hazards was obtained.  相似文献   
26.
乳腺癌术后即时乳房再造   总被引:1,自引:0,他引:1  
1990年3月至1994年3月,为7例乳腺癌术后用国产硅胶囊乳房假体充填进行即时乳房再造,均获成功,无手术并发症。经3个月至4年随访,手感柔软,双乳基本对称。对即时再造术的适应证、方法、时间的选择和注意事项进行了讨论。  相似文献   
27.
Fatal complications from illegal cosmetic injection of nonmedical-grade liquid silicone (polydimethylsiloxane) by unlicensed providers are becoming more common. Silicone embolization syndrome (SES) can rapidly progress to pneumonitis and diffuse alveolar hemorrhage. Prompt and aggressive management with high-dose steroids and lung-protective ventilation strategies to minimize acute respiratory distress syndrome (ARDS) can be lifesaving. We present the case of a patient presenting with abdominal pain and shortness of breath who quickly developed respiratory failure. The patient recently had received bilateral gluteal silicone injections from an unlicensed provider.  相似文献   
28.
The effects of nerve predegeneration on the preferential growth of regenerating axons were studied using a silicone Y-chamber model. This system provided a choice for axons to grow towards two distal nerve options, either a 7-day predegenerated nerve segment (PNS) or a fresh nerve segment (FNS). The rat peroneal or tibial nerve was inserted into the proximal intlet and the PNS and FNS of the corresponding nerve were inserted into the distal outlets. At 28 days postoperative, the size of the distal regenerate was significantly greater (26%) towards the PNS for the tibial nerve group. The density and number of regenerated myelinated axons in the distal nerve segment was greater on the PNS for both the tibial (97 and 88%, respectively) and peroneal (221 and 221%, respectively) nerve groups. In contrast, the elevated density and number of nonvascular nuclei was relatively constant for both PNS and FNS. Immunocytochemical and ultrastructural evidence support the hypothesis that the early activation of Schwann cells is primarily responsible for the enhanced regeneration and maturation observed in PNS. It is suggested that PNS might improve the outcome after clinical repair of injured peripheral nerves.  相似文献   
29.
Numerous scaffold materials have been developed for tissue engineering and regenerative medicine applications to replace or repair damaged tissues and organs. Naturally occurring scaffold materials derived from acellular xenogeneic and autologous extracellular matrix (ECM) are currently in clinical use. These biological scaffold materials possess inherent variations in mechanical properties. Spherical indentation or ball burst testing has commonly been used to evaluate ECM and harvested tissue due to its ease of use and simulation of physiological biaxial loading, but has been limited by complex material deformation profiles. An analytical methodology has been developed and applied to experimental load-deflection data of a model hyperelastic material and lyophilized ECM scaffolds. An optimum rehydration protocol was developed based on water absorption, hydration relaxation and dynamic mechanical analysis. The analytical methodology was compared with finite element simulations of the tests and excellent correlation was seen between the computed biaxial stress resultants and geometry deformations. A minimum rehydration period of 5 min at 37 °C was sufficient for the evaluated multilaminated ECM materials. The proposed approach may be implemented for convenient comparative analysis of ECM materials and source tissues, process optimization or during lot release testing.  相似文献   
30.
Despite their popular use in breast augmentation and reconstruction surgeries, the limited biocompatibility of silicone implants can induce severe side effects, including capsular contracture – an excessive foreign body reaction that forms a tight and hard fibrous capsule around the implant. This study examines the effects of using biomembrane-mimicking surface coatings to prevent capsular formations on silicone implants. The covalently attached biomembrane-mimicking polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), prevented nonspecific protein adsorption and fibroblast adhesion on the silicone surface. More importantly, in vivo capsule formations around PMPC-grafted silicone implants in rats were significantly thinner and exhibited lower collagen densities and more regular collagen alignments than bare silicone implants. The observed decrease in α-smooth muscle actin also supported the alleviation of capsular formations by the biomembrane-mimicking coating. Decreases in inflammation-related cells, myeloperoxidase and transforming growth factor-β resulted in reduced inflammation in the capsular tissue. The biomembrane-mimicking coatings used on these silicone implants demonstrate great potential for preventing capsular contracture and developing biocompatible materials for various biomedical applications.  相似文献   
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