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51.
目的:认识多发伤中骨折的主要特点,探讨内固定在救治中的意义。方法:回顾1994-08~1999-08间手术救治多发伤66例,对其161处骨折中的98处进行了“仿AO技术”有关方法内固定。结果:骨折均满意愈合;涉及骨折关节51个,功能恢复满意率为96.08%。结论:在多发伤中,骨折、合并伤与并发症远较“一般骨折”复杂、严重;有效固定骨折是一种重要的救命措施;内固定手术应争取在伤后24h进行,但如受条件制约,伤后1-3wk内手术也可获得满意效果;仿AO技术中的某些方法,如拉力螺钉、张力带钢丝及自动加压钢板等,用于内固定可使骨折获得卓有成效的稳定性。  相似文献   
52.
建立了蠕变局部损伤法模型,并给出单元进入损伤态的判据和失效的临界拉伸应变条件,局部蠕变损伤理论的实质就是试样是多种不同蠕变性能材料的统一,并由蠕变应力再分布得到证实,应用有限元对双缺口圆试样作了蠕变局部损伤分析,启裂时间和断裂蠕变应变值均与实验结果相吻合。  相似文献   
53.
运用止泻颗粒剂与思密达作对照治疗小儿消化不良性肠炎,治疗组136例,对照组80例,2组总有效率分别为95.5%,37.5%,疗效比较具有显著性差异,P<0.01。  相似文献   
54.
IGF-1在成骨样细胞增殖中的作用及与钾离子通道的关系   总被引:1,自引:0,他引:1  
目的 :研究胰岛素样生长因子 - 1(IGF - 1)促大鼠成骨样肉瘤细胞 (UMR10 6 )增殖作用及与钾离子通道活动的关系。方法 :采用磺基罗丹明 (SRB)染色法观察细胞增殖并用膜片钳技术记录细胞膜钾离子通道电流的变化。同时用3 H -TdR掺入测定DNA合成的改变。结果 :IGF - 1可以明显地促进UMR10 6细胞的增殖 ,且使3 H -TdR掺入率增加 93.5 7%。在含有生长因子IGF - 1(10 -8M)的培养液中培养 12h后 ,钾通道电流比对照有明显增加 ,而且用钾通道阻断剂后 ,3 H -TdR掺入率下降。结论 :IGF - 1可促进大鼠成骨样肉瘤的DNA合成和细胞增殖。且细胞膜钾通道的活动与此促增殖活动密切相关  相似文献   
55.
Xiao  Bihuan  Jiang  Yuan  Wang  Bin  Hu  Yang  Sun  Yan  Wu  Yan  Qiao  Shuai 《Lasers in medical science》2021,36(6):1261-1266
Lasers in Medical Science - Large-scale long-term retrospective study of noninsulated microneedle radiofrequency treatment on neck rejuvenation is lacking. We conducted a 3-year retrospective...  相似文献   
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58.
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC.  相似文献   
59.
Bulletin of Environmental Contamination and Toxicology - An effective method of iron extraction from bauxite residue was explored, and iron was used to prepare iron carbon composite material, which...  相似文献   
60.
Ni M  Ratner BD 《Biomaterials》2003,24(23):4323-4331
Nacre, also known as mother-of-pearl, constitutes the inner layer of mollusc shells. Nacre is a natural composite material consisting mostly of calcium carbonate in the aragonite crystal form and some organic matter. Previous studies have shown that geological aragonite, coral and nacre can convert hydrothermally to hydroxyapatite (HAP) in phosphate solution by a solid-state topotactic ion-exchange reaction. This conversion typically occurs within the range of 140-260 degrees C, although higher temperatures are possible. In this work, we have found that nacre can transform to HAP in a phosphate buffer solution at room temperature via a surface reaction. The morphology of the nacre-transformed HAP surface was investigated by scanning electron microscopy (SEM). The HAP surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS). A layer covered with packed particles was found in contrast to the tablet structure typical of nacre surfaces. XPS and SIMS indicated that the mineral phase of the nacre surface had converted from an aragonite phase to an HAP phase. Fourier transform infrared spectroscopy (FTIR) showed that phosphate (PO(4)) bands appeared after nacre was soaked in a phosphate buffer and the intensity of the PO(4) bands increased with exposure time. The FTIR was consistent with XPS and SIMS results. We suggest that this surface reaction occurs by a dissolution-precipitation mechanism. Calcium ions are released from the nacre surface, react with phosphate ions in the buffer solution, and then precipitate as HAP on the nacre surface.  相似文献   
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