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1.
颌骨牵张成骨中镍钛形状记忆合金的弹性性能比较   总被引:3,自引:0,他引:3  
目的 分析C3020φ1.0和B2025φ0.8 NiTi合金丝的性能,选择更适合牵张成骨实验的镍钛合金材料,探索镍钛合金丝在高温定型过程中最合适的记忆温度.方法 将C3020φ1.0和B2025φ0.8镍钛合金丝分为两个实验组,每组按照记忆处理时的温度不同(450℃、500℃、550℃、600℃)分为4个小组,高温记忆形状化处理后,分别对比室温下(18℃)和体温状态下(37℃)各实验组金属丝的复形能力的差异.结果 C3020φ1.0和B2025φ0.8两种不同规格的NiTi合金丝在室温状态下(18℃)和体温状态下(37℃)表现出的性能差异具有统计学意义,同一实验组每小组中金属丝的复形能力差异有统计学意义.结论 规格为C3020φ1.0mm的NiTi-SMA的性能更适合用于颌骨牵张成骨实验.在450℃、500℃、550℃、600℃ 4个不同的记忆温度下,500℃定型温度效果最理想.  相似文献
2.
To experimentally evaluate the ectopic osteogenetic capacity of synthesized BMP2-derived peptide P24 combined with poly lactic-co-glycolic acid (PLGA), Wistar rats were di- vided into two groups: group A, in which BMP2-derived peptide P24/PLGA complex was implanted, and group B which received simple PLGA implant. The complex was respectively implanted into the back muscles of rats. Samples were taken the 1st, 4th, 8th, and the 12th week after the implantation. Their bone formation was detected by X-ray examination, and tissue response was histologically ob- served. Western blotting was used for the detection of the expression of collagen Ⅰ (Col-Ⅰ) and osteopontin (OPN). There was acute inflammation in the tissue around both types of implants at early stage. The cartilage was found around implant areas 4 weeks after the implantation of BMP2-derived peptide p24/PLGA complex, 8 weeks after the implantation, osteoblasts were found, and 12 weeks after the implantation, typical trabecular bone structure was observed. In group B, after 12 weeks, no osteoblasts were found. It is concluded that PLGA is an ideal scaffold material for bone tissue engi- neering. BMP2-derived peptide can start endochondral ossification and is more effective in inducing ectopic osteogenesis.  相似文献
3.
Background Animal models are needed for the study of rapid tooth movement into the extraction socket through distraction osteogenesis of the periodontal ligament. Methods Modified distraction devices were placed on eight dogs between the first and third mandibular premolars on the left sides; similar placement of traditional straight wise appliances on the right sides served as the control. The experimental distractors were activated (0.25 mm/d) twice a day and the control devices were activated (100 g) for two weeks with consolidation periods at weeks two, three, six, and ten. Two dogs were sacrificed at each consolidation time point; rates and patterns of tooth movement, loss of anchorage, and periapical films were evaluated, and the affected premolars and surrounding periodontal tissues were decalcified and examined histologically. General observations, X-ray periapical filming and histology examination were performed. Results Distal movement ((3.66±0.14) mm) measured two weeks after modified distraction exceeded that achieved using the traditional device ((1.15±0.21) mm; P 〈0.05). Loss of anchorage was minimally averaged (0.34±0.06) mm and (0.32±0.07) mm in the experimental and control sides, respectively. By radiography, apical and lateral surface root resorptions on both sides were minimal. Alveolar bone lesions were never evident. Fibroblasts were enriched in periodontal ligaments and bone spicules formed actively along directions of distraction. Conclusions The canine model is suitable for the study of rapid tooth movement through distraction osteogenesis of the periodontal ligament. The technique accelerates tooth movement, periodontal remodeling, alveolar bone absorption, and may induce fibroblast formation, as compared to the traditional orthodontic method, without adversely affecting root absorption, bone loss, tooth mobility and anchorage loss.  相似文献
4.
In order to identify the differentially expressing gene of bone marrow mesenchymal stem cells (MSCs) stimulated by electromagnetic field (EMF) with osteogenesis microarray analysis, the bone marrow MSCs of SD rats were isolated and cultured in vitro. The third-passage cells were stimulated by EMFs and total RNA was extracted, purified and then used for the synthesis of cDNA and cRNA. The cRNA of stimulated group and the control group was hybridized with the rat oligo osteogenesis microarray respectively. The hybridization signals were acquired by using X-ray film after chemiluminescent detection and the data obtained were analyzed by employing the web-based completely integrated GEArray Expression Analysis Suite. RT-PCR was used to identify the target genes: Bmp1, Bmp7, Egf and Egfr. The results showed that 19 differentially expressing genes were found between the stimulated group and the control group. There were 6 up-regulated genes and 13 down-regulated genes in the stimulated group. Semi-quantitative RT-PCR confirmed that the expressions of Bmpl, Bmp7 mRNA of the stimulated group were up-regulated (P〈0.05) and those of Egf, Egfr were down-regulated (P〈0.05). It was suggested that the gene expression profiles of osteogenesis of the bone marrow MSCs were changed after EMF treatment. It is concluded that the genes are involved in skeletal development, bone mineral metabolism, cell growth and differentiation, cell adhesion etc.  相似文献
5.
一例Ⅰ型成骨不全家系的基因定位及突变检测   总被引:2,自引:0,他引:2  
目的对国内1例成骨不全(OI)家系进行基因突变及突变效应分析,为研究中国人群的成骨不全基因突变特点提供线索。方法对成骨不全Ⅰ型胶原基因COL1A1和COL1A2所在的17号染色体和7号染色体分别进行连锁分析,对致病基因做初步判断,然后用聚合酶链反应扩增致病基因外显子,并测序检出基因突变。结果该家系为COL1A1基因突变,所有患者在该基因的第8个内含子剪切受体位点处为AG→GG(IVS8-2A>G)突变。结论对比COL1A1基因突变数据库,该突变为一新发现突变。  相似文献
6.
腭部牵张延长的实验研究   总被引:1,自引:1,他引:0  
目的 :应用自制的腭部牵张装置延长腭裂模型犬的腭部 ,探讨治疗腭咽闭合不全的新方法。方法 :用 7只健康青春期杂种雄性犬为实验对象。手术形成腭裂模型 ,在实验侧行牵张成骨术。手术当天、术后 7、1 8、60d分别取印模 ,灌注石膏模型。制作术后 60d头颅骨标本。在模型和颅骨标本上测量各标志点间的距离。结果 :实验结束时 ,动物实验侧硬腭后缘均有不同程度的后退 ,牵张间隙内为新生骨组织。结论 :应用牵张成骨术可后退腭裂模型犬的硬腭后缘 ,延长硬腭  相似文献
7.
牵张成骨后移动骨段移位对早期血管生成的影响   总被引:1,自引:1,他引:0  
目的 研究牙槽骨垂直牵张成骨后移动骨段一步颊向移位较大距离对早期血管生成的影响.方法 杂种犬8只,拔除双侧下颌前磨牙1个月后,骨切开放置牵张器,间歇7 d后以1 mm/d速度牵张,垂直牵张高度为6 mm.垂直牵张完成后,每只犬的随机一侧作为实验侧,于牵张结束后第2天一步将移动骨段颊向移位3 mm,另一侧作为对照侧不改变移动骨段的颊向位置.完成垂直牵张后7 d处死动物并行墨汁灌注,图像分析血管面积比率.结果 实验动物均能顺利完成实验,实验侧移动骨段在垂直牵张后可较容易颊向移位3 mm,实验侧与对照侧牵张区内都有新生骨组织生成.组织学检查实验侧与对照侧有平行于牵张方向的血管生成,未见明显的血管破坏,图像分析血管面积比率差异无显著性.结论 在一定范围内,牙槽骨垂直牵张后移动骨段一步颊向移位可对牵张区新生骨组织塑形,避免轴向移位.这种操作并未明显破坏其早期的血管生成.  相似文献
8.
口内牵引成骨术的健康教育实施及评价   总被引:1,自引:0,他引:1  
目的探讨健康教育对口内牵引成骨术的手术前后恢复期实施情况及效果评价。方法对19例口内牵引成骨术患者,运用健康教育对手术期、间歇期、牵引期、固定期及出院,手术前后正畸,对患者心理调适、生活质量、饮食方式、口腔护理、牵引期等观察,采用特定方式进行效果评价。结果 19例患者通过健康教育的实施,使患者面容、面型的改善达到理想效果。结论健康教育的实施使19例患者无骨不连,骨坏死、感染等并发症的发生,使经过2年跟踪随访,定期检查,健康教育的实施及效果评价确切,使患者恢复正常的咬颌关系,咀嚼功能。  相似文献
9.
目的:研究异补骨脂素是否影响骨髓间充质干细胞向成骨细胞和脂肪细胞分化的能力。方法:不同浓度异补骨脂素分别处理在成骨或成脂诱导培养液中培养的大鼠骨髓间充质干细胞(bone marrow mesenchymal stem cells,BM-MSCs),培养14天,分别行亚甲基蓝、碱性磷酸酶(alkaline phosphatase,ALP)和油红O染色,并用提取处理后细胞总RNA和蛋白,RT-PCR和West-ern blot检测成骨或成脂相关基因的表达差异。结果:①异补骨脂素可提高大鼠BM-MSCs的总成纤维细胞集落形成单位(CFU-f)及ALP阳性CFU-f形成效率,并促进成骨相关基因的表达;②异补骨脂素可抑制大鼠BM-MSCs诱导脂肪滴的形成及过氧化物酶增殖体激活受体(peroxisome proliferator-activated receptor-γ,PPARγ)基因和蛋白的表达。结论:异补骨脂素可促进大鼠BM-MSC向成骨细胞分化并抑制其向脂肪细胞分化,其作用效果较补骨脂素更强。  相似文献
10.
目的:观察重组逆转录病毒人血管内皮生长因子165(retrovirus pLXSN/hVEGF165)基因转染对人骨髓基质细胞(hM-SCs)成骨能力的影响。方法:从健康志愿者全骨髓中分离培养人hMSCs,体外扩增纯化后随机分为4组:①retrovirus pLXSN/hVEGF165组:培养液中加入人血管内皮生长因子基因重组逆转录病毒1×1010OPU/ml,孵育24h后换普通培养液继续培养;②retrovirus pLXSN组:培养液中加入逆转录病毒空载体,其余处理与retrovirus pLXSN/hVEGF165组相同;③阳性对照组:培养液中添加地塞米松、抗坏血酸和β-甘油磷酸钠;④空白对照组:不给予特殊处理。各组细胞处理后2周,免疫组化观察VEGF表达,Von Kossa染色检测人hMSCs中骨胶原结节形成,全自动生化分析仪检测培养上清碱性磷酸酶活性。结果:经多次换液传代,人hMSCs呈均一梭形形态。处理后retrovirus pLXSN/hVEGF165组与阳性对照组细胞形态逐渐趋于扁平,突起减少。retroviruspLXSN组和空白对照组形态无明显变化。免疫组化染色见VEGF主要在胞浆内表达,...  相似文献
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