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991.
OBJECTIVE: To investigate the clinicopathlogical significance of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 expression in squamous cell carcinoma of maxillary sinus. METHODS: The expression of cyclinE, cyclinD1, P21WAF1/CIP1 and P27KIP1 was examined by the method of immunohistochemistry in inflammatory mucosa of maxillary sinus(10), inverting papilloma of maxillary sinus(20) and squamous cell carcinoma of maxillary sinus (50). RESULTS: (1) In inflammatory mucosa, inverting papilloma and squamous cell carcinoma, the positive immunostaining rates of cyclinD1 protein were 10.0%, 25.0%, 48.0% respectively (P < 0.05); cyclinE protein was 20.0%, 35.0%, 58.0% respectively (P < 0.05); P21WAF1/CIP1 protein was 80.0%, 65.0%, 40.0% respectively (P < 0.05) and P27KIP1 protein was 70.0%, 75.0%, 40.0% respectively (P < 0.05). (2) There was no significance between the clinical type, T stage and clinical stage of carcinoma of maxillary sinus and the expression of cyclinD1, cyclinE, P21WAF1/CIP1 and P27KIP1 (P > 0.05). (3) P21WAF1/CIP1 positive expression in highly, moderately and poorly differtiated carcinomas were 73.2% (11/15), 58.9% (11/19), 25.0% (4/16) respectively (P < 0.05). CONCLUSION: (1) With the development of the lesion, the positive immunostaining rate of cyclinE and cyclinD1 protein increases, while the rate of P21WAF1/CIP1 and P27KIP1 protein decreases. (2) P21WAF1/CIP1 expression is associated with tumour cell differentiation. (3) The mutual mechenism of cell cycle regulators plays an important role in the squamous cell carcinoma of maxillary sinus. The quantity and the frequency of four kinds of gene expression increase with the progression of maxillary sinus carcinogenesis. 相似文献
992.
BACKGROUND: Deposition of proteins on surfaces of medical devices has been recognized to putatively relate to the process of regulation of biomaterial-associated complications by attachment of fibrin clots, eukaryotic cells, and microbes. The molecules adsorb to a varying extent, depending not only on the physicochemical properties of the biomaterial, but also on the composition of the host fluid. OBJECTIVE: Adsorption of proteins on catheters exposed both ex vivo and in vitro to dialysate of patients on peritoneal dialysis (PD) was studied. METHODS: Peritoneal dialysis effluent was collected from 5 patients with end-stage renal disease on continuous ambulatory PD. Tenckhoff catheters were obtained from 16 patients. Deposition of proteins on excised Tenckhoff catheters and tubing of different materials exposed to PD effluent in vitro was studied using 125iodine-labeled antibodies. Adhesion of Staphylococcus aureus and Staphylococcus epidermidis strains was quantified on tubing exposed to PD effluent in vitro. RESULTS: The presence of albumin, transferrin, immunoglobulin G, fibrinogen, fibronectin, von Willebrand factor, vitronectin, and thrombospondin was determined at various concentrations in PD effluent. All proteins analyzed were detected on PD catheters removed from patients. The extent of protein deposition on Tenckhoff catheters exposed to PD effluent, in vitro, rapidly reached a plateau and remained constant, as it did on polyvinyl chloride and polyethylene tubing. Adhesion of staphylococci was enhanced on Tenckhoff catheters exposed to PD effluent compared to unused PD solution. CONCLUSIONS: The data identify surface exposed proteins that may serve as adhesion sites for microbes on peritoneal catheters indwelled in patients undergoing PD. 相似文献
993.
Medical and Surgical Dermatology - 相似文献
994.
目的探讨乳腺癌术后胸部气压固定带的制作及临床应用价值。方法将64例乳腺癌术后患者随机分为观察组和对照组各32例,对照组采用传统的绷带加压包扎,观察组采用自行设计并制作的胸部气压固定带加压包扎。观察两组术后引流量、拔管时间及并发症的发生情况。结果观察组皮下积液发生率显著低于对照组(P〈0.05),术后24h引流量、置管时间显著少于/短于对照组(均P〈0.01)。结论乳腺癌术后使用胸部气压固定带加压固定可减少渗出,缩短置管时间,降低皮下积液发生率。 相似文献
995.
MED术中应用自制器械处理后纵韧带钙化及骨赘增生 总被引:1,自引:0,他引:1
目的探讨脊柱后路显微内镜(microendoscopic disectomy,MED)手术治疗腰椎间盘突出症合并后纵韧带钙化及椎体后缘骨赘增生的方法. 方法 MED手术中应用自制弧形纤维环刀和L形打入器治疗115例该类患者. 结果全组随访12~30个月,平均22个月,按MacNab标准:优、良109例,可5例,差1例,优良率94.8(109/115).未出现硬脊膜破裂及神经孙上,未发生椎间隙感染,无中转开放手术. 结论正确运用MED技术,配合采用自制器械及相应的改良方法,能较好地处理合并后纵韧带钙化及椎体后缘骨赘增生的难题,进一步扩大了手术适应证范围,提高了疗效及安全性. 相似文献
996.
Fabrication of porous hollow silica nanoparticles and their applications in drug release control. 总被引:11,自引:0,他引:11
Preparation and characterization of porous hollow silica nanoparticles (PHSN) for controlled release applications were investigated. Through orthogonally designed experiments, the optimal synthesis conditions for the preparation of PHSN were obtained and the produced PHSN were characterized by BET, SEM, TEM and IR. Scanning and transmission electron microscopy images revealed their hollow shell-core structure and also demonstrated that the size and shape of PHSN are determined by the templating CaCO3 nanoparticles. The produced PHSN were applied as a carrier to study the controlled release behaviors of Brilliant Blue F (BB), which was used as a model drug. Being loaded into the inner core and on the surfaces of the nanoparticles, BB was released slowly into a bulk solution for about 1140 min as compared to only 10 min for the normal SiO2 nanoparticles, thus exhibited a typical sustained release pattern without any burst effect. In addition, higher BET of the carriers, lower pH value and lower temperature prolonged BB release from PHSN, while stirring speed showed little influence on the release behavior. It showed that PHSN have a promising future in controlled drug delivery applications. 相似文献
997.
护理业务流程再造现状分析及对策 总被引:9,自引:1,他引:8
目的了解护士对护理业务流程再造的知晓度及需求,找出流程再造存在的问题,针对存在问题提出相应的对策。方法采用问卷调查方法,调查广东省16所县级以上医院287名护士对护理业务流程再造的认识情况。结果护士对护理流程再造的知晓现状与临床状况不尽人意;护士认为进行护理流程优化再造是必要的和重要的;现有的护理流程存在的问题是流程流于形式、不完善及实用性不强。结论要进行护理流程再造,必须转变观念,加强在职培训,设计精简、方便、实用的护理流程。 相似文献
998.
三氧化二砷脂质体的制备及其对鼠脑胶质瘤的影响 总被引:1,自引:0,他引:1
目的研究三氧化二砷(As2o3)脂质体注射液对大鼠体内C6胶质瘤细胞凋亡的影响。方法采用超声薄膜分散法制备As籼脂质体,将126只成瘤大鼠分为As2O3脂质体组、As2O3组、生理盐水组。原子荧光法检测注射As2O3脂质体和As2O3后大鼠脑组织中As2O3浓度。从电镜、TUNNEL和大鼠生存时间等方面研究As2O3脂质体对C6胶质瘤的影响。结果As203,脂质体提高了As2O3的血-脑屏障通过。电镜和TUNEL检测显示:As203脂质体组细胞凋亡率给药后3d为(13.53±1.68)%,7d为(20.03±0.79)%,多于As2O3组和盐水组。动物生存时间亦优于其他两组。结论超声薄膜分散法是制备As2O3脂质体的较好方法。As203脂质体可较As203更明显地诱导鼠脑胶质瘤细胞凋亡,延长载瘤鼠的生存期。 相似文献
999.
1000.