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21.
Bone-particle-impregnated bone cement: an in vivo weight-bearing study   总被引:2,自引:0,他引:2  
To evaluate an experimental inorganic-bone-particle-impregnated bone cement, canine hip prostheses were implanted in dogs using a regular bone cement on one side and the experimental bone cement on the other. In a preliminary feasibility study, bone ingrowth into the resorbed bone-particle spaces was established 3 months after implantation in three dogs. In a more detailed study, twenty-eight (28) dogs were divided in four groups to delineate the effects of time on the phenomena of bony ingrowth. One month after implantation, active bone ingrowth into the bone cement was obvious. By 3 months postimplantation, the ingrowth appeared to have traversed the thickness of the bone-particle-impregnated cement. By the fifth month, most of the interconnected inorganic bone particles were replaced by new bone. At the end of a year, the ingrown bone was mature and negligible new bone activity was present. Biomechanical pushout tests closely corroborated the histologic observations. The maximum shear strength of the cement/bone interface of the experimental side reached 3.6 times that of the control side at 5 months postimplantation. No further improvements were seen at 12 months postimplantation. A viable bone/cement interface may result in a better orthopedic implant fixation system by combining the advantages of both cement for immediate rigidity and biological ingrowth for longterm stability.  相似文献   
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髋关节置换手术中采用标准型假体时,术前只能大致选取假体,术中还要预备多个假体,往往手术时间增长。为了解决这一问题,本文提出一种利用计算机优选标准型髋关节假体的方法。从X线片中获取患者股骨解剖数据。利用这些解剖数据和股骨近端截面平均数据库三维重建患者股骨近端,重建出的股骨近端模型使优选标准假体成为可能。理论分析表明,该方法切实可行。  相似文献   
24.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.  相似文献   
25.
目的:探讨超声检查在诊断乳腺典型髓样癌中的临床意义。方法:按严格的病理诊断学标准将病例重新分类为乳腺典型髓样癌和非典型髓样癌,比较两者间声像学特征的异同。结果:32例中有13侧重新诊断为乳腺典型髓样癌;另外19例为非典型髓样癌。13例典型髓样癌患者中的10例边界整齐光滑;全部19例非典型髓样癌病人没有一例边界光滑,或者边界呈锯齿状(16例),或者边界光滑伴局部不规则(3例)。非典型与典型髓样癌间肿瘤边界的规则性有明显的差异。结论:如果超声检查提示肿瘤边界呈锯齿状或肿瘤边界光滑伴局部不规则,应行整个肿瘤的病理评估防止典型髓样癌的过诊断。  相似文献   
26.

Objective  

To observe the effects of essential garlic oil (EGO) on vascular cell adhesive molecule-1 (VCAM-1) expression of endothelial cells and monocyte-endothelial cell adhesion rate induced by interleukin-lα(IL-lα).  相似文献   
27.
Dai  Wei  Zhuang  Zong  Ling  Haiping  Yang  Yongbo  Hang  Chunhua 《Neurosurgical review》2021,44(1):515-527
Neurosurgical Review - To quantitatively synthesize the comparative efficacy and safety of the most common surgical approaches including endonasal transsphenoidal endoscopic surgery (ETES),...  相似文献   
28.
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   
29.
W Mao  L Zeng  Q Ma  Y Chen  Z Dai  P Tang  X Guo  D Li  W Su 《眼科学报》1990,6(3-4):88-90
We report here the preliminary effects of zinc iontophoresis in treatment of 26 Rp patients who had decreased zinc serum level or abnormal ratio of serum copper to zinc. Through more than 20 to 30 times of therapy, the vision of 15.38% eyes increased more than "3 lines", 4% eyes increased more than 5 degrees in the visual field, 13.46% eyes improved in dark adaptation threshold (greater than 1.0), the visual functions of the rest eyes were slightly improved or unimproved. The fundus didn't change before & after treatment. There were no changes of ERG in 8 eyes of 4 cases. In addition, the advantages and disadvantages between Zn iontophoresis and Zn compound taken orally, the improvement of vision by direct electric current therapy, the relationship between the metabolism of Zn element and Vit A and influence of Zn over the mechanism of dark adaptation were also briefly discussed.  相似文献   
30.
目的 :探索口腔粘膜扁平苔藓 (OLP) P53蛋白的表达及其在癌变诊断中的应用价值。方法 :采用 S- P免疫组化方法 ,观察在 2 5例 OLP、2 0例鳞癌 (OSCC)中 P53蛋白的表达。结果 :1 P53蛋白的阳性表达在 OLP早期已出现 ,各组间 P53阳性表达率间有显著性差异。2在 OSCC中其阳性表达率高达 80 % ,随着细胞异常增生程度的增高而增高。结论 :1在 OSCC的形成过程中 ,抑癌基因 P53的失活可能参与调节作用 ;2 P53蛋白作为判断 OLP癌变的辅助性参考指标 ,具有一定的可行性  相似文献   
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