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51.
Objective To determine the best duration for exerting the cyclic pressure under which the tissue-engineered cartilage is constructed. Methods Free chondrocytes isolated from rabbit articular cartilage were seeded into polylactic acid-co-glycolic acid(PLGA) scaffolds after expansion in vitro, and ran-domized into 4 groups. In Groups 1 to 3, chondrocytes were cultured under daily cyclic pressure (0 ~ 200 kPa, 0.1Hz) for 4 hours, 8 hours, 12 hours respectively; Group 4 was a control in which no pressure was exerted. In each group, after 2 weeks of culture, the tissue engineered cartilages were observed in vitro and assessed by his-tological staining of liE. Next, the content of DNA and the secretion of type Ⅱ collagen and GAG in cartilages were detected quantitatively. Results Under the daily cyclic pressure (0 ~200 kPa, 0.1 Hz), the scaf-fold-chondrocytes complex in the group of 8 hours got the largest volume, smooth, lucidus, and elastic surface, the most queuing chondrocytes, and the highest content of type Ⅱ collagen and GAG (P < 0.01). Conclusions Since chondrecytes are baro-senstive, the metabolism of chondrocytes can be affected by the time of cyclic pressure. Under the effect of 0 ~200 kPa, 0.1Hz, the daily cyclic pressure of 8 hours may be optimal for chondrocytes to multiply and synthesize extracellular matrixes such as type Ⅱ collagen and GAG. 相似文献
52.
[目的]观察人骨髓间充质干细胞在速固化磷酸钙骨水泥支架中的增殖和生长情况。[方法]将速固化壳聚糖-磷酸钙骨水泥支架材料预先成形。采用全骨髓法分离人骨髓间充质细胞并在体外对细胞进行培养和扩增。72h首次换液,细胞融合80%传代,取第3代细胞用于实验。将细胞与磷酸钙骨水泥支架复合培养,分别利用四甲基偶氮唑蓝MTT法及扫描电镜等检测细胞在材料中的增殖和生长情况。[结果]用酶标仪检测OD值提示共培养后,支架内的细胞数量逐渐增加。扫描电镜结果显示支架材料内部为多孔结构,孔内见有细胞生长,细胞表面可见分泌颗粒。[结论]速固化壳聚糖-磷酸钙骨水泥对人骨髓间充质干细胞有较好的细胞相容性,细胞可在材料内黏附和增殖,是理想的骨组织工程支架材料。 相似文献
53.
Decisions about which health-care interventions represent adequate value to collectively funded health-care systems are as widespread as they are unavoidable. In the case of new pharmaceuticals, many countries now require formal cost-effectiveness analysis to inform this decision-making process. This requires evidence on parameters associated with health-related utilities, treatment effects, resource use, and costs, for which data from available regulatory trials are invariably absent or highly uncertain. This uncertainty results from a number of factors including the predominance of intermediate end points in the clinical evidence-base and the limited period of follow-up of patients in clinical studies. Despite these imperfections in the evidence base, decisions about whether new pharmaceuticals are sufficiently cost-effective for reimbursement cannot be side-stepped. Data limitations do, however, require the use of rigorous analytical methods to support decision making. Probabilistic decision models and value of information analysis offer a means of structuring decision problems, synthesizing all available data, characterizing the uncertainty in the decision, quantifying the cost of uncertainty, and establishing the expected value of perfect information. This analytical framework is important because it addresses two fundamental questions about new pharmaceuticals. First, is the product expected to be cost-effective on the basis of existing evidence? Second, is additional research concerning the product itself cost-effective? In addressing these questions, the analytical framework can establish when sufficient evidence exists to sustain a claim for a new pharmaceutical to be cost-effective. 相似文献
54.
Elizabeth R. Woods M.D. M.P.H. Jonathan D. Klein M.D. M.P.H. Gina M. Wingood Sc.D. M.P.H. Eve S. Rose M.S.P.H. David Wypij Ph.D. Sion Kim Harris Ph.D. Ralph J. Diclemente Ph.D. 《The Journal of adolescent health》2006,38(6):753.e1-753.e7
PurposeAlthough an adult model of patient-provider mutual exchange of information has been proposed, there is no guiding model for adolescents or measurement methodology. Our purpose was to develop a new scale of patient-provider interaction for adolescents accessing reproductive health care and at risk for sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV), and assess the reliability and validity of the scale.MethodsThe Adolescent Patient-Provider Interaction Scale (APPIS) was developed from the Roter and Hall theory of doctor-patient relationships, previously validated adolescent satisfaction and communication scales, and focus group and individual elicitation interviews. To assess construct validity, the new nine-item APPIS was compared with the satisfaction scale used by the Young Adult Health Care Survey (YAHCS), and Kahn’s Provider Communication Scale. Pearson correlation coefficients were used to examine convergence across scales, and factor analysis of the APPIS was performed.ResultsThe study recruited 192 African American girls aged 17.9 ± 1.7 years (range 15–21 years) from three sites: a county STD clinic (n = 51), urban adolescent clinic (n = 99), and a family planning clinic (n = 42). Most participants (85%) rated their overall health care highly (≥ 7 on a 10-point scale); 49% felt that both the provider and patient were “in charge” of the visit, and 88% “strongly agreed” or “agreed” that there was an equal “exchange of information” during the visit. The APPIS showed good internal consistency (Cronbach alpha = .75), and moderate convergence with the six-item YAHCS scale (r = .57, p < .001) and seven-item Kahn scale (r = .48, p < .001). Three factors emerged from exploratory factor analyses, supporting our conceptualization of patient-provider interaction as being multi-dimensional.ConclusionsA new theory-based scale of adolescent patient-provider interaction compares favorably with previous scales of health care satisfaction and communication. The new APPIS may be useful for evaluating approaches to improve health care outcomes for adolescents at-risk for STDs and HIV. 相似文献
55.
县级医院医疗仪器管理对策 总被引:4,自引:1,他引:3
医疗仪器在疾病诊断和医疗中的作用越来越大,完善的管理不仅可提高仪器的使用寿命和安全性,关系到医院的经济效益和社会效益,更关系到患者的利益.文章结合实际,提出县级医院医疗仪器管理对策. 相似文献
56.
管状膨体聚四氟乙烯用于组织工程支架材料的动物实验研究 总被引:6,自引:0,他引:6
目的:研究膨体聚四氟乙烯(ePTFE)植入动物体内后与机体的关系。方法:管状膨体聚四氟乙烯两端闭合,内充DMEM培养液,埋入家兔皮下,观察宿主生命情况,于术后1、2、4、6周取出标本,行大体及光镜下观察。结果:家兔在植入膨体聚四氟乙烯材料及DMEM培养液后存活情况良好,DMEM培养液在1周时即已完全无色透明;4周时膨体聚四氟乙烯与周围组织有粘连,6周时粘连紧密;光镜下观察,各时间点材料间隙均可见着色,1周时可见少量淋巴细胞浸润,无血管及组织细胞。材料内壁未见细胞附着。结论:植入膨体聚四氟乙烯材料及少量DMEM培养液对宿主动物存活无影响;管内外液体可相互交通,管状膨体聚四氟乙烯可作为组织工程化尿道的支架材料。 相似文献
57.
骨髓间充质干细胞定向肝细胞样分化的研究 总被引:20,自引:3,他引:17
目的探讨骨髓间充质干细胞定向肝细胞样分化的诱导条件,为肝组织工程提供新的种子细胞来源。方法分离小鼠骨髓间充质干细胞,在特定肝细胞培养液中用肝细胞生长因子(HGF)和表皮细胞生长因子(EGF)定向诱导。在倒置显微镜下观察细胞形态。应用免疫荧光法鉴定细胞性质。结果骨髓间充质干细胞经HGF和EGF诱导7d后变为肝细胞样圆形;2周后免疫荧光染色可见分化后细胞表达肝细胞标志物CK18和白蛋白。结论骨髓间充质干细胞在特定条件诱导下可以向肝细胞方向分化。有可能作为肝组织工程的种子细胞来源。 相似文献
58.
59.
Objective To determine the best duration for exerting the cyclic pressure under which the tissue-engineered cartilage is constructed. Methods Free chondrocytes isolated from rabbit articular cartilage were seeded into polylactic acid-co-glycolic acid(PLGA) scaffolds after expansion in vitro, and ran-domized into 4 groups. In Groups 1 to 3, chondrocytes were cultured under daily cyclic pressure (0 ~ 200 kPa, 0.1Hz) for 4 hours, 8 hours, 12 hours respectively; Group 4 was a control in which no pressure was exerted. In each group, after 2 weeks of culture, the tissue engineered cartilages were observed in vitro and assessed by his-tological staining of liE. Next, the content of DNA and the secretion of type Ⅱ collagen and GAG in cartilages were detected quantitatively. Results Under the daily cyclic pressure (0 ~200 kPa, 0.1 Hz), the scaf-fold-chondrocytes complex in the group of 8 hours got the largest volume, smooth, lucidus, and elastic surface, the most queuing chondrocytes, and the highest content of type Ⅱ collagen and GAG (P < 0.01). Conclusions Since chondrecytes are baro-senstive, the metabolism of chondrocytes can be affected by the time of cyclic pressure. Under the effect of 0 ~200 kPa, 0.1Hz, the daily cyclic pressure of 8 hours may be optimal for chondrocytes to multiply and synthesize extracellular matrixes such as type Ⅱ collagen and GAG. 相似文献
60.
男科学组织工程研究前景 总被引:4,自引:3,他引:1
利用组织工程技术进行细胞移植的设想 ,已经为男科领域的组织再建工作提供了许多可能。为改善、修复或替代现有组织的功能 ,组织工程的应用研究 ,已经在睾丸间质细胞、睾丸假体、阴茎海绵体、阴茎假体等方面开展。虽然大多数再建工作仍然停留在实验阶段 ,但是有些技术也被用于临床 ,并取得满意的结果。本文简要地综述了组织工程在男科学的应用 相似文献