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61.
良性骨巨细胞瘤周边生物学行为及SMAa微血管标记的意义   总被引:7,自引:2,他引:7  
目的:检测良性骨巨细胞瘤(Giant Cell Tumor of Bone,GCT)周边组织病理学改变及瘤组织对微血管的侵袭。方法:收集1995-1998年我科切除的8例良性GCT瘤段,对其病灶周边进行组织病理学及血管平滑肌肌动蛋白a(Smooth Muscular actin,SMAa)免疫组织化学研究。结果:组织学良性GCT可具有侵蚀皮质骨、松质骨及周围软组织的能力,边界处有大量新生微血管密度形成,肿瘤中多核巨细胞可侵袭微静脉,肿瘤细胞可由此进入血管。结论:良性GCT仍具有局部侵袭和潜在转移的能力。  相似文献   
62.
We studied the rates of revision for 53,698 primary total hip replacements (THRs) in nine different groups of disease. Factors which have previously been shown to be associated with increased risk of revision, such as male gender, young age, or certain types of uncemented prosthesis, showed important differences between the diagnostic groups. Without adjustment for these factors we observed an increased risk of revision in patients with paediatric hip diseases and in a small heterogeneous 'other' group, compared with patients with primary osteoarthritis. Most differences were reduced or disappeared when an adjustment for the prognostic factors was made. After adjustment, an increased relative risk (RR) of revision compared with primary osteoarthritis was seen in hips with complications after fracture of the femoral neck (RR = 1.3, p = 0.0005), in hips with congenital dislocation (RR = 1.3, p = 0.03), and in the heterogenous 'other' group. The analyses were also undertaken in a more homogenous subgroup of 16,217 patients which had a Charnley prosthesis implanted with high-viscosity cement. The only difference in this group was an increased risk for revision in patients who had undergone THR for complications after fracture of the femoral neck (RR = 1.5, p = 0.0005). THR for diagnoses seen mainly among young patients had a good prognosis, but they had more often received inferior uncemented implants. If a cemented Charnley prosthesis is used, the type of disease leading to THR seems in most cases to have only a minor influence on the survival of the prosthesis.  相似文献   
63.
BACKGROUND: Neutrophils are the predominant phagocytes in the early stages of myocardial ischemia-reperfusion response and are also implicated in the development of tissue damage. This study examined the role of recruited macrophages in the evolution of this tissue injury. METHODS: Farm pigs were subjected to 30 minutes of myocardial ischemia followed by 30 minutes of reperfusion. Biopsy samples were taken from the control, ischemic, and ischemic-reperfused left ventricle wall and processed for both morphologic and biochemical analyses. In situ production of tumor necrosis factor-alpha was evaluated by Western blot and immunofluorescence. A full hemodynamic evaluation was also performed. RESULTS: Myocardial ischemia and early reperfusion caused marked neutrophil and macrophage tissue accumulation and tumor necrosis factor-alpha production by the injured tissue. Immunofluorescence studies allowed us to localize tumor necrosis factor-alpha predominantly in tissue-infiltrating macrophages. No depression in the global myocardial contractile function was observed, either during ischemia or after reperfusion. CONCLUSIONS: These data suggest that the newly recruited macrophages within the ischemic and early post-ischemic myocardium may play a role in promoting neutrophil tissue infiltration and subsequent neutrophil-induced tissue dysfunction by producing tumor necrosis factor-alpha.  相似文献   
64.
65.
颅内动静脉畸形动物模型制作与栓塞的实验研究   总被引:2,自引:0,他引:2  
目的 探讨颅内动静脉畸形(arteriovenous mal-formation,AVM)动物模型的制作与其在栓塞研究中的应用。方法 以中国实验小型猪(Chinese Experimental Mini-pigs,CEMPs)颅底微血管网(rete mirabile,ReM)为AVM的畸形团,经右颈动静脉吻合并结扎右颈外动脉等建立AVM动物模型,用a-氢基丙烯酸正丁酯(NBCA)胶和Embosphere颗粒分别栓塞,模型建立和栓塞前后行血管造影,并取栓塞组织(ReM)、颈动静脉吻合口和脑做组织病理学检查。结合造影影像和组织病理学发现,探索模型的应用、颈动静脉吻合口的闭塞原因和模型改进方法。结果 在7只CEMPs中成功制作了AVM动物模型,该模型在血管结构、造影影像、栓塞表现和栓塞后病理改变上与人脑AVM的相似。4只动物颈动静脉吻合口血管腔内有血栓形成,其余3只吻合口血管塌陷皱缩,腔内无血栓。死亡动物脑组织病理表现为缺血性梗塞。结论 尽管本方法对于建立颅内AVM动物模型更简单可行,适用于栓塞材料的栓塞研究和介入医师的培训,但该模型仍为急性期模型,其应用十分有限。如何防止模型动静脉吻合口的闭塞和让动物能够耐受栓塞,需要进一步的研究。  相似文献   
66.
Meningeal melanocytomas are rare tumors and malignant transformation of these lesions is even rarer. The authors report on a case of a 57-year-old man who presented with a melanocytoma located at the L5-S1 level. After gross-total resection of the tumor, it recurred 1 year later as a malignant melanoma. In addition, multiple subcutaneous metastases were found at that time. The patient was treated with radiation therapy (5000 cGy). Five months later metastases in the liver and the left ninth rib were discovered. The pertinent literature is reviewed and disease criteria are presented to distinguish meningeal melanocytoma from malignant melanoma and from meningiomas or schwannomas containing melanotic pigment. Patients and investigators should be cautioned that a meningeal melanocytoma may recur and transform into a malignant melanoma.  相似文献   
67.
68.
Objective To determine the value of helical computed tomography (HCT) and color doppler flowing imaging (CDPI) in evaluating the resectability of pancreatic cancer. Methods The clinical data of 114 patients with pancreatic cancer who had been admitted to the Affiliated Hospital of North Sichuan Medical College from January 1995 to December 2002 were retrospectively analyzed. The values of HCT and CDPI in assessing the resectability of pancreatic cancer were determined according to the results of operation and pathological examina-tion. All the data were analyzed by chi-square test and Fisher exact probability. Results Of all patients, 109 were examined by HCT, 97 by CDPI and 96 by HCT+CDPI. For patients examined by HCT, the resection rates of pancreatic head cancer, pancreatic body and tail cancer and total pancreatic cancer were 45.3% (39/86), 26.3% (5/19) and 0 (0/9), respectively. The resection rate of pancreatic head cancer was higher than that of pancreatic body and tail cancer (χ2=8.965, P<0.05). With the increase of tumor size, the invasion rate and metastasis rate were increased and the resection rate was decreased (z=6.15, 5.35, 7.18, P<0.01). The sensitivity rate and specificity rate were 77.8% and 82.2% of HCT, 73.3% and 80.6% of CDPI, 90.6% and 92.4% of HCT+CDPI in assessing the resectability of pancreatic cancer. The values of Kappa identity test of HCT, CDPI and HCT+CDPI were 0.58, 0.52 and 0.82, respectively. Conclusions Combined application of HCT and CDPI can further improve the accuracy in assessing the resectability of pancreatic cancer.  相似文献   
69.
INTRODUCTION: We studied the renal transplantation results of living donor compared with cadaveric donor kidney transplantations. PATIENTS AND METHODS: One hundred thirty-six living donor transplantations performed during the period of 1990 to 2003 (group 1) were compared with a control group of 4304 cadaveric donor transplantations (group 2), paired 1:1 with group 1 patients, according to the period of transplantation, the primary renal disease, the transplant number, as well as the recipient and donor ages. RESULTS: There were no differences regarding patient or graft survival during a 10-year follow-up. CONCLUSIONS: The benefit of performing living donor kidney transplantations is the possibility of having the donor available even before beginning dialysis treatment.  相似文献   
70.
Yao A  Li X  Pu L  Zhong J  Liu X  Yu Y  Zhang F  Kong L  Sun B  Wang X 《Transplant immunology》2007,18(1):37-43
OBJECTIVE: Graft size is one of the major risk factors in adult-to-adult living donor liver transplantation and rapid regeneration is an essential post-operative requirement. Ischemic preconditioning (IPC) has been shown to be an effective strategy in the reduction of hepatic ischemia-reperfusion injury and stimulation of liver regeneration. This study was designed to evaluate the effects of IPC on liver regeneration in small-for-size liver grafts. METHODS: We employed a rat orthotopic liver transplantation model using small-for-size (30%) grafts, in the presence or absence (control) of IPC (10 min of ischemia followed by 15 min of reperfusion). Survival rate, graft injury, hepatocellular proliferation, cell cycle progression, Stat3 activation, as well as TNF-alpha and IL-6 expression were assessed. RESULTS: IPC significantly enhanced the extent of graft injury and hindered hepatic regeneration in small-for-size liver grafts. The 7-day survival rate was also reduced by IPC, but failed to reach statistical significance. IPC did not affect TNF-alpha levels, but significantly decreased the elevation of IL-6 after reperfusion. These findings were correlated with down-regulation of cyclin E and cyclin D1, and decreased numbers of PCNA-positive nuclei in IPC grafts. These results were inconsistent with Stat3 activation, as P-Stat3 exhibited a stronger and prolonged pattern of expression in the IPC group, compared to controls. CONCLUSIONS: Ischemic preconditioning may impair liver regeneration in small-for-size liver grafts by decreasing IL-6 and blunting cell cycle progression, through a mechanism at least partially independent of Stat3.  相似文献   
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