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991.
单枚椎间融合器并对侧经皮椎弓根螺钉固定的生物力学研究 总被引:1,自引:0,他引:1
目的对单枚融合器联合单侧钉棒系统固定的生物力学性能进行评价。方法5具新鲜小牛腰椎标本,建立以下力学模型:A组:双侧开窗+双枚融合器置入+双侧椎弓根钉棒固定;B组:单侧小关节切除+单枚融合器斜向置入+同侧椎弓根钉棒固定;C组:单侧开窗+单枚融合器置入+同侧椎弓根钉棒固定;D组:单侧开窗+单枚融合器置入+对侧椎弓根钉棒固定。在生物力学平台上测试各试验组在不同工况下的ROM值。结果A组的固定最稳固,各工况下ROM值最低。B组的前后抗弯ROM值与A组差异无显著性,其左右侧弯和旋转方向的稳定性较A组有所降低。与B组比较,D组的前后弯曲性能与B组差异无显著性,其左右侧弯方向的ROM低与B组。两组的抗旋转ROM值差异无显著性。C组的左右抗弯及抗旋转性能均差于B、D组。结论单枚椎间融合器联合对侧椎弓根钉棒固定是一种力学性能较为优良组合,可以替代单侧斜向融合器并同侧椎弓根钉棒技术用于下腰椎微创手术。 相似文献
992.
Thirteen premenopausal women with stress urinary incontinence (SUI), 6 with SUI and prolapse, 9 with prolapse, and 19 without
prolapse were enrolled to observe the content change of collagen type III and the expression of decorin mRNA in paraurethral
connective tissues. Collagen type III from transvaginal biopsies was assayed by immunohistochemical staining and decorin mRNA
was detected by real-time PCR. Premenopausal women with SUI had a significantly decreased level of collagen type III. Decorin
mRNA expression was significantly increased in both premenopausal SUI+prolapse group and premenopausal prolapse group reflected
by the decrease of ΔCt value compared to their corresponding controls. The results suggest that a high level of decorin mRNA
might be associated with the reduced content of collagen type III, resulting in a less flexible form of extracellular matrix
in the connective tissue in SUI and prolapse patients.
This study was supported by a grant from the Fujian Science and Technology Bureau Foundation (grant no. 2000I1003). 相似文献
993.
Objective To evaluate a serf-designed diagnostic protoeol which can early detect a femoral neck fracture for patients with a femoral shaft fracture. Methods From September 2005 to June 2007, a self-developed protocol was used to detect an ipsilateral femoral neck fracture for all the patients with femoral shaft fracture who had sought treatment in our department. This protocol consisted of anteroposterior plain radiography of internal rotator, intraoperative fluoroscopy of the hip, a fine (2 mm) cut computed to-mographic scan through the femoral neck, postoperative anteroposterior and lateral plain radiography of the hip in the operating room prior to awakening the patient, at the time of follow-up anteroposterior and lateral plain radiography of the hip in the presence of hip pain. The diagnostic effects of the protocol were compared with those of conventional diagnosis used for all the patients with femoral shaft fracture who had sought treatment in our department from September 2003 to August 2005. A chi-square analysis comparing the protocol group (September 2005 to June 2007) and the non-protocol group (September 2003 to August 2005) was used to assess the early and delayed diagnosis rates for an associated ipsilateral femoral neck fracture. Results The earlydiagnosis rate of an associated femoral neck fracture by the protocol was 93.8%, markedly higher than that by conventional method (46.2%), with statistically significant difference (χ2 = 4.069, P =0.044). Conclu-sion In presence of a femoral shaft fracture. this protocol consisting of plain radiography of intemal rotator, intraoperative fluoroscopy of the hip, fine cut computed tomographic scan of the femoral neck, postoperative plain radiography of the hip, and follow-up plain radiography of the hip in the presence of hip pain, may sig-nificantly improve the diagnostic rate of an associated femoral neck fracture. 相似文献
994.
Objective To investigate if rat enhancer of split- and hairy-related protein-2 (SHARP-2) short hairpin RNA interference (shRNAi) prolongs the survival time of rat kidney transplant recipients. Methods Gene recombinant procedures, transfection and co-transfection were carried out to introduce short hairpin RNA interference sequences target for SHARP-2 into 3rd generation self-inactivated lentiviral-ViraPower packaging mix. Limiting dilution method was used for viral titration. Real-time PCR was employed for quantification of gene expression. Rat kidney transplantation was utilized to investigate the effect of SHARP-2 gene silence on the recipient survival. Results A lentiviral-based shRNAi construct LV-SHARP-2iC showed 84% SHARP-2 gene silence efficiency in normal rat kidney cells. At multiplicity of infection 20, 57% T cells could be transfected by lentivirus with spinoculation method. In activated T cells, SHARP-2 g ene silence resulted in 61.3% and 68.7% reduction of intedeukin 2 (IL-2) and interferon γ (IFN-γ) gene expression. When donor kidney was perfused with 5×107 TU LV-SHARP-2iC, the median survival time prolonged for 4-5 days as compared to blank and scramble control groups. Conclusions A recombinant lentivirus LV-SHARP-2iC that effectively silence SHARP-2 gene expression is constructed successfully, leading to the inhibition of IL-2 and IFN-γ. LV-SHARP-2iC treatment can prolong the survival time of rat kidney transplant recipients. 相似文献
995.
OBJECTIVE: To evaluate safety and efficacy of additional palatal implants for snoring treatment. STUDY DESIGN AND SETTING: A prospective case series at two clinical sites in an office setting. Patients who did not have an acceptable reduction in snoring intensity after an initial 3 implant procedure received additional implants. Bed partners rated snoring intensity on a 10 cm visual analog scale (VAS) at baseline and 90 days postprocedure. RESULTS: Snoring intensity VAS decreased significantly from 6.4 +/- 2.3 to 4.6 +/- 2.9 (P < 0.01) for patients who received an additional fourth implant, and to 4.1 +/- 2.8 after the 5th implant (P<0.01). Epworth sleepiness scale scores also decreased significantly for patients who received additional fourth or fifth implants. There were no adverse events. CONCLUSIONS: Additional palatal implants for snoring treatment were safe and effective in this case series. SIGNIFICANCE: Additional implants may offer relief for snorers not responding to the initial 3 implant procedure. 相似文献
996.
Qi S Zhao H Ma A Liu L Wang X Xu D Lin G Tamura K Jiang H Daloze P Chen H 《Microsurgery》2007,27(4):268-270
Baohuoside-1 (B-1), a recently introduced novel immunosuppressant that was proved to be potent in inhibition of T and B cell proliferation and B-1, also prevents cardiac allograft rejection in rodents. The present study further proved that monotherapy of B-1's analogue B-1 aglycone effectively prolongs cardiac allograft survival and combination therapy of B-1 aglycone with tacrolimus (FK506) produces synergistic effect in prevention acute cardiac allograft rejection in the rat. . 相似文献
997.
Kim JH Kim HI Lee KW Yu JE Kim SH Park HS Park CG Ihm SH Ha J Kim SJ Lee HK Ahn C Park KS 《Xenotransplantation》2007,14(1):60-66
BACKGROUND: Porcine pancreas is a potential source of material for islet xenotransplantation. However, the difficulty in isolating islets, because of their fragility and the variability of isolation outcome in donor age and breed, represents a major obstacle to porcine islet xenotransplantation. In this study, we compared the islet isolation yield of specific pathogen-free (SPF) Chicago Medical School (CMS) miniature pigs with that of another miniature pig breed and market pigs from a local slaughterhouse. METHODS: Nine adult CMS miniature (ACM) pigs (>12 months), six young CMS miniature (YCM) pigs (6-7 months), four adult Prestige World Genetics (PWG) miniature (APM) pigs (>12 months), and 13 adult market (AM) pigs from a local slaughterhouse were used for islet isolation. RESULTS: The islet yield per gram of pancreas from ACM pigs (9589 +/- 2823 IEQ/g) was significantly higher than that from APM pigs (1752 +/- 874 IEQ/g, P < 0.05), AM pigs (1931 +/- 947 IEQ/g, P < 0.05), or YCM pigs (3460 +/- 1985 IEQ/g, P < 0.05). Isolated islets from ACM pigs were significantly larger than those from AM pigs or YCM pigs. The in vitro and in vivo function of isolated islets showed no difference among experimental groups. The pancreases of ACM pigs contained higher mean islet volume density percentages and larger size of islets than those of AM or APM pigs. CONCLUSIONS: We isolated extremely high yields of well-functioning islets from ACM pigs bred under SPF conditions. SPF CMS miniature pigs should be one of the best porcine islet donors for clinical porcine islet xenotransplantation. 相似文献
998.
999.
1000.
Upregulation of connective tissue growth factor in a rat model of chronic allograft nephropathy 总被引:3,自引:0,他引:3
AIM: To study the expression of connective tissue growth factor (CTGF) in transplanted rat kidney and its relationship with chronic allograft nephropathy (CAN). METHODS: Kidney transplantation was performed from Lewis to Fisher 344 allogeneic rat strain, and kidney grafts were harvested at the eighth, 12th and 16th week. The morphological changes were studied, and collagen deposition was determined by Masson trichrome stain. Serum creatinine was examined. The fibrotic process and the CAN grades were evaluated according to Banff 97 schema. The expressions of transforming growth factor beta, CTGF and alpha-smooth muscle actin were detected to assess the development of grafted kidney fibrosis and to discuss their relationships. Spearman correlation was used for correlation study between CTGF expression and development of CAN. RESULTS: Serum creatinine was promoted in a time-dependent manner. Morphological changes suggested that the grafted kidneys were under abnormalities. At the end stage, focal segmental glomerulosclerosis was seen; tubular epithelial cells lost their phenotype and interstitial fibrosis was notable. Masson trichrome stain showed significant collagen accumulation in a time-dependent manner. Immunohistochemistry and western blotting results showed that the transforming growth factor beta, CTGF and alpha-smooth muscle actin expression were markedly promoted compared with the control group. CTGF was mainly expressed in the plasm of proximal tubular epithelial cells based on the severity of CAN. CONCLUSION: Connective tissue growth factor might play an important role in the pathological changes of CAN after kidney transplantation. The expression of CTGF in epithelial cells could act as a molecular marker of interstitial fibrosis and CAN. 相似文献