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排序方式: 共有265条查询结果,搜索用时 15 毫秒
51.
52.
Methotrexate osteopathy in patients with osteosarcoma 总被引:5,自引:0,他引:5
53.
DIM Robinson BSc MB BS S. Lertsumitkul MB BS FA Billson FRACO FRACS † LP Robinson DO FRACO FRACS † 《Clinical & experimental ophthalmology》1993,21(2):79-85
A retrospective study of 179 eyes in 127 patients who underwent trabeculectomy at Sydney Eye Hospital under the supervision of two surgeons between 1977 and 1982 was carried out. Survival analysis by life table method shows cumulative two, five, and 10 year success rates to be 78%, 70%, and 67% respectively, with mean duration of intraocular pressure control (IOP<21 mmHg) being 88 months. Anti-glaucoma medication improved the long-term survival significantly (Hazard Ratio of 0.49 and P = 0.01) so that when the definition for failure is taken as IOP >20 mmHg while using medication, the two, five and 10 year success rates were 89%, 87% and 86% respectively. A rise in average intraocular pressure is seen between two weeks and three months after trabeculectomy. The improvement in long-term success rate with use of topical steroids was suggestive (Hazard Ratio of 0.69) but not conclusive (P = 0.21). No difference was found in survival comparing fornix versus limbal based flap technique. 相似文献
54.
血管内皮生长因子在口腔颌面骨组织工程中的应用 总被引:1,自引:0,他引:1
目的:了解血管内皮生长因子促进骨再生和修复作用的机制及应用方式,探讨其在口腔颌面骨组织工程中的应用前景。资料来源:应用计算机检索PubMed数据库1994-01/2006-02有关血管内皮生长因子促进成骨的文章,检索词“Vascular endothelial growth factor,Bone formation,Maxillofacial bone,Bone defect”,限定文章语言种类为English。同时计算机检索中国期刊全文数据库1994-01/2006-02期间的相关文章,检索词“血管内皮生长因子、成骨、颌骨”,限定文章语言种类为中文。资料选择:对资料进行初审,选取符合要求的有关文章找全文。纳入标准:①血管内皮生长因子及其受体分子结构方面的文章。②血管内皮生长因子促进成骨作用的基础研究和临床研究。③血管内皮生长因子在颌骨组织工程中应用的基础研究和临床研究。排除标准:重复或类似的同一研究、Meta分析、个案报道。资料提炼:共收集到186篇有关血管内皮生长因子促进成骨作用的文章,排除重复或类似的同一研究,30篇符合要求(其中2篇为血管内皮生长因子及其受体分子结构方面的文献,18篇为血管内皮生长因子促进成骨作用的基础研究和临床研究方面的文献,10篇涉及血管内皮生长因子在颌骨组织工程中应用的研究)。资料综合:①国内外有关血管内皮生长因子促进成骨作用的机制为:通过促进内皮细胞增殖、血管生成,调节骨组织血供并参与骨的发育形成;作为旁分泌因子参与骨形成代谢;通过调节成骨细胞和破骨细胞的活性促进骨组织的再生、修复和重建。②血管内皮生长因子在骨组织工程中的应用方式主要有外源性应用和内源性应用,外源性应用就是将外源性血管内皮细胞生长因子加入到支架和细胞的复合体中,使它通过促进血管化、调节参与成骨的多种因子及成骨细胞和破骨细胞的活性,提高成骨效能。内源性应用就是利用基因技术,将人血管内皮细胞生长因子基因转入种子细胞,使种子细胞持续的产生血管内皮细胞生长因子,为骨形成提供足够的血管化和调节骨细胞的活性。③动物实验已证实血管内皮生长因子对颌骨牵张成骨和颌骨缺损修复起着促进作用。结论:应用外源性和内源性血管内皮生长因子构建的组织工程骨可促进骨形成和骨缺损修复,用它来加快颌面骨组织工程的骨形成和缩短疗程在理论上是可行的。 相似文献
55.
56.
Marco Aurélio Peres Aluisio J Barros Karen Glazer Peres Cora LP Araújo Ana MB Menezes 《Community dentistry and oral epidemiology》2009,37(2):123-133
Abstract – Objective: To investigate the main dental caries life course determinants and predictors of dental caries at age 12. Methods: This study was nested in a population‐based birth cohort started in 1993 in Pelotas, Brazil. A sample of 359 children was followed‐up. Dental examinations and interviews were performed at 6 and at 12 years old. Dental caries (DMFT) at 12 years old was the outcome. Exploratory variables included socioeconomic and demographic variables at birth, children’s nutritional and development characteristics, primary dental caries, oral health related behaviors and dental service use at age 6 and 12. Poisson regression was used in order to provide relative risk ratio estimates. Attributable risk or etiology fraction and population attributable risk for both main early life variables were calculated. Dental caries prediction (DMFT ≥ 1) at 12 years old was tested using logistic regression analyses. Results: Children who presented height‐for‐age deficit at 12 months (RR 1.50 CI: 95% = 1.03–2.18), children who showed a DMFT of 1–3 and 4–19 at 6 years (RR = 2.01; CI: 95% = 1.33–3.03, and RR = 2.66; CI: 95% = 1.81–2.53, respectively) and those children aged 12 in the highest tertile of proportion of teeth experiencing gingival bleeding (RR = 1.58; CI: 95% = 1.11–2.24) presented a higher level of dental caries at age 12. Attributable risk for dental caries at age 12 were 79.1% and 74.2% for deficit in height for age at 12 months and for primary dental caries at age 6 years respectively; population attributable risk for dental caries at age 12 were 3.1% for deficit in height for age at 12 months and 64.9% for primary dental caries at age 6. The level of accuracy in predicting dental caries at age 12 by using life course socioeconomic, behavioral and clinical data was modest. Conclusions: The results of this study support the hypothesis linking social, biological and behavioral exposures and dental caries at 12 years old. In addition, the findings reinforce the lack of accuracy of dental caries predictors therefore limiting the individuals high‐risk approach as a public health strategy. 相似文献
57.
Allergic bronchopulmonary aspergillosis, known to be associated with cystic fibrosis in older patients, occurred in 7 young atopic children with cystic fibrosis. The diagnosis was suggested by the onset of, or the increase in, asthmatic symptoms accompanied by major chest x-ray changes ranging from total collapse of a lung or lobe to extensive but changing areas of consolidation. Each of the children had a blood eosinophilia, positive type I skin tests to Aspergillus fumigatus, and reversible airways obstruction. Most had a positive type III skin test and circulating precipitins to A. fumigatus, with raised IgE levels which contained specific antibodies to the fungus on radioallergosorbent (RAST) test. None had advanced suppurative chest disease of cystic fibrosis. None was given specific antifungal agents; two received systemic treatment with corticosteroids, the other received additional drugs for their asthma. Two developed total collapse of one lung, one child being only 2 years old. Five have had recurrences of pulmonary shadowing typical of allergic aspergillosis but are not showing significant progression of their cystic fibrosis lung disease. Our experience suggests that there should be an increased awareness of this condition, particularly its association with extensive pulmonary collapse or consolidation in children with cystic fibrosis who are atopic. 相似文献
58.
脂质体载水溶性药物出现的共同问题是药物的包封量低、稳定性差。本文以甲硝唑(Ⅰ)为水溶性药物模型,进行疏水性结构修饰,得其肉豆蔻酸酯(Ⅱ)前体药物,分别进行Ⅰ和Ⅱ的脂质体研究,结果表明Ⅱ在脂质体中的包封率较Ⅰ提高10倍以上,渗漏速率降至十分之一,制成含Ⅱ的脂质干膜,经超声分散,可得合乎要求的重组型脂质体,为解决脂质体载药的稳定性问题提供有效途径。体外抗阿米巴原虫试验,镜检观察到载药脂质体进入阿米巴原虫的细胞内,且100%抑制原虫所需剂量Ⅱ脂质体是Ⅰ游离药的二分之一。因此药物疏水化修饰是解决脂质体载水溶性药物稳定性问题的理想途径。 相似文献
59.
目的:探索构建组织工程化仿生骨种植体的方法流程,并制备成骨细胞-可吸收载体种植体样品,同时尝试建立组织工程化非承载骨种植体的评价方法。方法:实验于2001-05/2005-12分别在天津市口腔医院组织工程实验室和天津大学材料学院高分子材料研究所完成。①通过相分离技术制备壳聚糖/明胶三维网络多孔支架,在支架材料表面原位沉积纳米级的羟基磷灰石晶体,构筑纳米羟基磷灰石/壳聚糖/明胶仿生骨组织工程支架材料,并进行表征和性能检测。②用酶消化法和条件培养法分离、诱导培养中国小型猪成骨细胞作为组织工程种子细胞。③用静态复合共培养法体外构建2种骨组织工程种植体样品:成骨细胞-纳米羟基磷灰石/壳聚糖/明胶仿生骨种植体,成骨细胞-纳米羟基磷灰石/胶原种植体。④采用扫描电镜、透射电镜、FDA荧光、LDH、MTT等定期观测仿生骨样品中细胞形态、细胞增殖速率、碱性磷酸酶活性、矿化结节形成等指标,以比较样品的细胞增殖活性和成骨活性。结果:①成功构筑了具有良好的生物相容性和力学相容性的纳米羟基磷灰石/壳聚糖/明胶,这种材料具有适于细胞黏附与生长的(90±1)%的孔隙率,孔径为100 ̄300μm的微孔结构,且原位沉积的纳米羟基磷灰石晶体的粒径为50nm左右,接近与天然骨的组成。②自中国小型猪腿骨成功分离培养了成骨细胞,并在诱导培养条件下,表现出很强的增殖活力和成骨活性,适合作为实验用骨组织工程的种子细胞。③成功构建了两种成骨细胞-可吸收载体种植体样品:经检验仿生构建的小型猪成骨细胞-纳米羟基磷灰石/壳聚糖/明胶种植体具有细胞亲和性和体外成骨活性。结论:①在体外成功仿生构建了结构与活性接近天然骨的骨组织工程种植体--纳米羟基磷灰石/壳聚糖/明胶种植体。②初步建立了仿生组织工程化非承载骨种植体的评价方法,为其进一步用于体内修复颅颌骨组织损伤的深化研究提供了实验数据和科学依据。 相似文献
60.
Koster T; Rosendaal FR; Briet E; van der Meer FJ; Colly LP; Trienekens PH; Poort SR; Reitsma PH; Vandenbroucke JP 《Blood》1995,85(10):2756-2761
A deficiency of protein C (PC), antithrombin, or protein S is strongly associated with deep-vein thrombosis in selected patients and their families. However, the strength of the association with venous thrombosis in the general population is unknown. This study was a population-based, patient-control study of 474 consecutive outpatients, aged less than 70 years, with a first, objectively diagnosed, episode of venous thrombosis and without an underlying malignant disease, and 474 healthy controls who matched for age and sex. Relative risks were estimated as matched odds ratios. Based on a single measurement, there were 22 (4.6%) patients with a PC deficiency (PC activity, less than 0.67 U/mL or PC antigen, less than 0.33 U/mL when using coumarins). Among the controls, the frequency was 1.5% (seven subjects). Thus, there is a threefold increase in risk of thrombosis in subjects with PC levels below 0.67 or 0.33 U/mL [matched odds ratio, 3.1; 95% confidence interval (CI), 1.4 to 7.0]. When a PC deficiency was based on two repeated measurements, the relative risk for thrombosis increased to 3.8 (95% CI, 1.3 to 10); when it was based on DNA-confirmation, the relative risk increased further to 6.5 (95% CI, 1.8 to 24). In addition, there was a gradient in thrombosis risk, according to PC levels. The results for antithrombin are similar to those for PC, although less pronounced (relative risk, 2.2; 95% CI, 1.0 to 4.7). We could not find an association between reduced total protein S (relative risk, 0.7; 95% CI, 0.3 to 1.8) or free protein S levels (relative risk, 1.6; 95% CI, 0.6 to 4.0) and thrombosis risk. Although not very frequent, PC and antithrombin deficiency are clearly associated with an increase in thrombosis risk. 相似文献