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81.
GAG-augmented polysaccharide hydrogel: a novel biocompatible and biodegradable material to support chondrogenesis 总被引:29,自引:0,他引:29
Sechriest VF Miao YJ Niyibizi C Westerhausen-Larson A Matthew HW Evans CH Fu FH Suh JK 《Journal of biomedical materials research》2000,49(4):534-541
The quality of articular cartilage engineered using a cell-polymer construct depends, in part, on the chemical composition of the biomaterial and whether that biomaterial can support the chondrocytic phenotype. Acknowledging the supportive influence of tissue-specific matrix molecules on the chondrocytic phenotype, we have combined chondroitin sulfate-A (CSA) and chitosan, a glycosaminoglycan (GAG) analog, to develop a novel biomaterial to support chondrogenesis. Chitosan is a polycationic repeating monosaccharide of beta-1,4-linked glucosamine monomers with randomly located N-acetyl glucosamine units. Chitosan may be combined with the polyanionic CSA such that ionic crosslinking results in hydrogel formation. Bovine primary articular chondrocytes, when seeded onto a thin layer of CSA-chitosan, form discrete, focal adhesions to the material and maintain many characteristics of the differentiated chondrocytic phenotype, including round morphology, limited mitosis, collagen type II, and proteoglycan production. Our findings suggest CSA-chitosan may be well suited as a carrier material for the transplant of autologous chondrocytes or as a scaffold for the tissue engineering of cartilage-like tissue. 相似文献
82.
XU Xiu lin ZHU Nai shuo Department of medical instrumentation Shanghai medical instrumentation college China Lab.of molecular immunology School of life sciences Fudan University Shanghai China 《中国生物医学工程学报(英文版)》2002,(2)
INTRODUCTION From integrallevel and celllevel,the research of organism and diseasediagnosishave already entered molecular level.Molecular biology is the science to researchstructure and function of organism macromolecule.Based on differentgene code se-… 相似文献
83.
CHEN Sheng-li BIN Xiao-nong HUANG Zi-cheng.Department of Interventional Radiology The First Municipal People′s Hospital of Guangzhou Guangzhou Medical College.Guangzhou China 《现代临床医学生物工程学杂志》2007,(4)
目的探讨经支气管动脉灌注化疗(BAI)治疗晚期肺癌近期疗效的影响因素。方法回顾性分析1990年3月至2006年6月间胸部X线片复查资料相对完整的82例经BAI治疗的原发性晚期肺癌的近期疗效。结果完全有效(CR)10例(12.2%)、部分有效(PR)32例(39.0%)、轻微有效(MR)23例(28.0%)、稳定(SD)15例(18.3%)、进展(PD)2例(2.4%)。单因素方差分析结果显示,半月时肿瘤缩小率(TDR1/2month)(χ2=25.92,P<0.01)、BAI次数(TBAI)(χ2=17.70,P<0.01)、肿瘤大小(Tsize)(χ2=14.21,P<0.01)和肿瘤血供丰富程度(χ2=6.59,P<0.01)对近期疗效的影响具有统计学意义。对年龄、病理类型等12项协变量进行二项分类Logistic回归分析,采用向后删除法经10步二次迭代,得到Logistic回归方程:P(1)=1/[1 e-(-8.953 2.656TDR1/2month 1.382TBAI 1.230Tsize)],方程对BAI近期疗效有效与无效的预测正确率分别为85.7%和70.0%。结论第1次BAI后半月时的肿瘤缩小率、BAI治疗次数和肿瘤的大小是影响BAI近期疗效的因素。 相似文献
84.
Effects of benactyzine on action potentials and contractile force of guinea pig papillary muscles 总被引:1,自引:0,他引:1
DING Zhongren )△ ZHANG Yan ) ZHANG Guiqing ) KE Jun ) HU Xiangjie ) )Department of Hematology Peking Union Medical Hospital Chinese Academy of Medical Sciences Beijing )Department of Pharmacology Henan Medica 《郑州大学学报(医学版)》2000,35(2)
INTRODUCTIONBenactyzineisasyntheticblockerofM receptorpos sessingsmoothmusclerelaxantpropertiesandquinidine likeactiononheart[1] .Benactyzineiseffectiveinrestor ingcirculatoryfunctiondisturbedbyorganophosphatepoi soning[2 ,3] .Previousstudiessuggestedthatbena… 相似文献
85.
目的 :黑色素瘤 B1 6细胞热休克蛋白 -抗原肽复合物 (HACs)及其粗提物 (HAC- CEs)的制备 ,以及它们的免疫原性和抑瘤效应的研究。方法 :应用 Sephacryl S- 2 0 0凝胶过滤制备HAC- CEs,应用亲和层析纯化 HACs,并测其免疫功能和抑瘤效应。结果 :应用凝胶过滤制备的HAC- CE3、HAC- CE4、HAC- CE5和应用亲和层析纯化的 HAC60 ,HAC75和 HAC97均不同程度地降低肿瘤发生率、延迟肿瘤发生时间和减少移植黑色素瘤 C57BL/6J小鼠死亡率 ;同时 ,伴有小鼠脾细胞 IFN-γ和 IL- 2分泌活性及 CTL杀伤率的增加。结论 :分子量为 60 0 0 0~ 970 0 0的 HACs具有免疫原性和抑瘤效应 ,本研究为制备肿瘤疫苗提供重要的实验依据。 相似文献
86.
胃癌细胞肿瘤坏死因子受体的研究 总被引:2,自引:0,他引:2
目的 探讨人胃癌细胞肿瘤坏死因子受体 ( TNFR)的数目与胃癌细胞分化程度以及与肿瘤坏死因子突变体 ( TNF- m)细胞毒效应之间的关系。方法 以12 5I- TNF- m为配体 ,用放射配体结合分析法 ,检测了高、中、低不同分化程度的体外培养胃癌细胞 ( MKN2 8、SGC790 1、MKN4 5)的 TNFR,同时用 MTT比色法研究了 TNF- m对三株胃癌细胞的细胞毒效应。结果 三株胃癌细胞 TNFR数目分别为每细胞 9.8× 10 -12 nmol、5.6× 10 -12 nmol、3.2× 10 -12 nmol,三者之间比较 ,TNFR数目差异有显著性 ( P<0 .0 5)。解离常数基本一致 ,同一温度时三株胃癌细胞 TNF- m的内化率几乎相等 ,且呈温度依赖关系。TNFR的半衰期大约为 90分钟 ,胞膜与胞浆 TNFR数目之比约为 1∶ 2 ,TNF- m对三株胃癌细胞的最大杀伤率分别为 86%、60 %、34 % ,差异有显著性 ( P<0 .0 5) ,且 39℃时的杀伤率高于37℃时的杀伤率。结论 胃癌细胞表面 TNFR数目与胃癌分化程度相关。 TNF- m的细胞毒效应与TNF数目及 TNF- m的内化量有关。 相似文献
87.
Ages at different reproductive events, numbers of menstrual cycles in between and breast cancer risk
One hundred and seventy-five pathologically confirmed new cases of female breast cancer in National Taiwan University Hospital were selected as the case group. Four hundred and fifty-seven inpatient controls were individually matched for each case by age and date of admission. Information of reproductive factors and potential confounders were collected from questionnaire interview and medical records. Menstrual cycles before and after first fuIl-term pregnancy were estimated from the questionnaire. Conditional logistic regression was used to estimate the effects of reproductive risk factors and numbers of menstrual cycles before and after first full-term pregnancy. After adjusting for educational level, body mass index, family history of breast cancer and oral contraceptive use, age at menarche and menopause only showed borderline significance. Age at first full-term birth predicted breast cancer risk better. Parity was the most important protective factor. Number of menstrual cycles before first full-term pregnancy was also positively associated with breast cancer risk with linear trends. 相似文献
88.
Lephart SM Warner JJ Borsa PA Fu FH 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1994,3(6):371-380
Shoulder proprioception was measured in 90 subjects who were assigned to three experimental groups: group 1 (n = 40), healthy college-age subjects; group 2 (n = 30), patients with anterior instability; and group 3 (n = 20), patients who have had surgical reconstruction. Kinesthesia and joint position sense were measured with a specially designed proprioception testing device. The results revealed no significant differences in proprioception between dominant and nondominont shoulders in group 1 for any test condition. Significant differences (p < 0.05) were revealed between the unstable and uninvolved shoulder for both kinesthesia and joint position sense in group 2. No significant mean differences were revealed between the surgical and contralaterol shoulder in group 3 under any test condition. This series of studies provides evidence that proprioceptive deficits caused by partial deafferentiation result when copsuloligomentous structures are damaged. Reconstructive surgery appears to restore some of these proprioception characteristics. 相似文献
89.
PreliminaryevaluationofpelvicvascularbedisolationchemotherapyinthetreatmentofadvancedcervicalcarcinomaJiangSenandPostgraduate... 相似文献
90.
Fu YL Hu YX Ling HL Ye ZZ Liang T Zhang MG Liu YK Kang B Luo YJ He SY Lian YJ 《Infectious diseases in obstetrics and gynecology》1994,1(5):235-241
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection. 相似文献