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91.
经皮肾囊穿刺封闭术治疗难治性肾病综合征临床研究 总被引:1,自引:0,他引:1
目的 探讨介入疗法对难治性肾病综合征 (RNS)的疗效。方法 将 6 4例RNS随机分为A ,B两组 ,A组 32例 ,经皮肾囊穿刺向每一肾脂肪囊 (肾囊 )内注入 2 %利多卡因 ,每周 2次 ,同时口服强的松、洛汀新、潘生丁等治疗 ,B组 32例 ,应用强的松、洛汀新、潘生丁等治疗。结果 A组总有效率为 84 .4 % ,B组为 6 5 .6 % ,两组比较 (P <0 .0 5 ) ,A组 1年内复发率低 ,为 2 9.6 % ,B组为 71.4 % ,比较两组 (P <0 .0 1)。结论 利多卡因经皮肾囊内穿刺注射封闭疗法是目前治疗RNS最有效的方法之一 ,值得临床进一步的推广应用。 相似文献
92.
骨髓间质干细胞体外预构组织工程化肌腱的实验研究 总被引:2,自引:1,他引:1
目的探讨骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性,为构建组织工程化肌腱寻求理想方法.方法以贴壁法分离、培养骨髓间质干细胞,并检测CD44.在实验组中将骨髓间质干细胞置入含胶原-聚羟基乙酸的DMEM培基中培养:在对照组中将骨髓间质干细胞置入DMEM培基中培养.通过MTT方法比较两组的细胞活性和生长情况,并对实验组进行超微观察.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架在体外预构组织工程化肌腱.结果以贴壁法原代培养骨髓间质干细胞,11天细胞即汇合成片,检测CD44示阳性.骨髓间质干细胞接种于胶原-聚羟基乙酸中混合培养后14天生长良好,始终保持89%以上的细胞活力,与对照组比较无显著差别;实验组细胞数未发生明显改变,而对照组从第4天开始即发生增殖.透射电镜示实验组细胞培养14天后仍保持旺盛的分泌功能.体外预构的组织工程化肌腱具有良好的形态,细胞伸展成梭形,沿聚羟基乙酸缝线大致平行排列.结论骨髓间质干细胞与胶原-聚羟基乙酸的细胞相容性好.以骨髓间质干细胞为种子细胞,以胶原-聚羟基乙酸为支架可在体外初步预构组织工程化肌腱. 相似文献
93.
Experimental Study on Allogenic Decalcified Bone Matrix as Carrier for Bone Tissue Engineering 总被引:11,自引:0,他引:11
The biocompatibility and osteogenic activity of allogenic decalcified bone matrix (DBM) used as a carrier for bone tissue engineering were studied. Following the method described by Urist, allogenic DBM was made. In vitro, DBM and bone marrow stromal cell (BMSC) from rab-bits were co-cultured for 3-7 days and subjected to HE staining, and a series of histomorphological observations were performed under phase-contrast microscopy and scanning electron microscopy (SEM). In vivo the mixture of DBM/BMSC co-cultured for 3 days was planted into one side of muscules sacrospinalis of rabbits, and the DBM without BMSC was planted into other side as con-trol. Specimens were collected at postoperative week 1, 2 and 4, and subjected to HE staining, and observed under SEM. The results showed during culture in vitro, the BMSCs adherent to the wall of DBM grew, proliferated and had secretive activity. The in vivo experiment revealed that BMSCs and undifferentiated mesenchymal cells in the perivascular region invaded gradually and proliferated together in DBM/BMSC group, and colony-forming units of chondrocytes were found. Osteoblasts,trabecular bone and medullary cavity appeared. The inflammatory reaction around muscles almost disappeared at the second weeks. In pure DBM group, the similar changes appeared from the sur-face of the DBM to center, and the volume of total regenerate bones was less than the DBM/BMSC group at the same time. The results indicated that the mixture of DBM and BMSC had good bio-compatibility and ectopic induced osteogentic activty. 相似文献
94.
Christina Djokoto George Tomlinson Stephen Waldman Marc Grynpas Angela M. Cheung 《Journal of clinical densitometry》2004,7(4):448-456
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS. 相似文献
95.
目的 探讨外科手术切口病因及预防措施.方法 回顾分析我科自2001年5月~2005年7月施行大、中手术后发生切口脂肪液化的60例病例.结果 肥胖,术中皮下脂肪层使用电刀,术中切口器械挤压时间长,大块组织钳夹,老年人、糖尿病等可引发切口脂肪液化.结论 手术切口脂肪液病因较多,肥胖、术中使用电刀、器械挤压时间长、老年人糖尿病均为重要影响因素. 相似文献
96.
97.
Identification of differentially expressed genes in omental adipose tissues of obese patients by suppression subtractive hybridization 总被引:1,自引:0,他引:1
Qiu J. Ni Y. H. Gong H. X. Fei L. Pan X. Q. Guo M. Chen R. H. Guo X. R. 《南京医科大学学报(自然科学版)》2007,27(5):427-427
To identify differentially expressed genes between obese individuals and normal control, we have undertaken suppression subtractive hybridization (SSH). Omental adipose tissues were obtained via abdominal surgery for appendicitis in both 13 obese subjects[BMI (body mass index) 〉 30 kg/m(2)] and 13 normal subjects (BMI 〉 18 and 〈 25 kg/m(2)). 相似文献
98.
Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%). 相似文献
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%). 相似文献
99.
目的 研究pcDU6载体质粒介导的转化生长因子β1(TGF-β1)短发夹RNA(shRNA)对人血清白蛋白(HSA)致人肾近曲小管上皮细胞(HK2细胞)增殖,TGF-β1、结缔组织生长因子(CTGF)和纤连蛋白(FN)表达的影响,并探讨有关机制。方法 构建TGF-β1shRNA的pcDU6载体质粒,体外培养HK2细胞株。采用脂质体转染将表达TGF-β1shRNA的pcDU6质粒载体(pcDU6-A1-A2和peDU6-B1-B2)分别导人实验组细胞。用HSA(5g/L)刺激HK2细胞12h或24h。四甲基偶氮唑盐(MTF)比色法测定细胞增殖水平。RT-PCR半定量分析HK2细胞中TGF-β1、CTGF和FNmRNA的表达水平;双抗夹心酶联免疫吸附法检测HK2细胞培养液中TGF-β1及FN蛋白质水平。结果 HK2细胞在HSA刺激下,其TGF-β1、CTGF及FNmRNA的表达明显上调,培养液中TGF-β1和FN的蛋白质含量亦明显升高(P〈0.05)。与pcDU6空载体组比较,pcDU6载体质粒介导的TGF-β1shRNA干扰组TGF-β1、CTGF及FNmRNA的表达明显下调(P〈0.05)。TGF-β1shRNA转染HK2细胞后12h或24h,细胞培养液中TGF-β1和FN蛋白质含量明显下降,HK2细胞增殖被部分抑制(P〈0.05)。在细胞增殖、TGF-β1、CTGF及FN基因表达方面,TGF-β1shRNA干扰组组间比较,以及pcDU6空载体转染组与HSA刺激组比较,差异均无统计学意义。结论 peDU6载体质粒介导的TGF-β1shRNA能够明显抑制HSA刺激下HK2细胞增殖、TGF-β1、CTGF和FN基因的表达。HSA刺激HK2细胞增殖及CTGF和FN基因的过表达可能通过TGF-β1介导。 相似文献
100.
[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