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91.
目的:建立家猪胸腰段脊髓火器贯通伤模型和改良Allen's打击伤后全瘫模型,观察伤后促凋亡基因p53基因的早期表达。方法:实验于2005-05/08在解放军第一七五医院实验室完成。取健康雄性家猪20只,单纯随机分为3组:①火器伤组:9只,在全麻状态下制作胸腰段(L1~L2)脊髓火器伤模型,分为伤后1,3,6h3个时间处死。②打击伤组:9只,L1节段脊髓行改良Allen’s打击,致伤力为500g·cm,处死时间同前。③空白对照组:2只,只麻醉,不造模,伤后6h处死。伤后不同时间点(伤后1,3,6h)和不同节段(伤点、近伤点、中伤点及远伤点)取材,采用SP法进行P53蛋白免疫组化染色,用TJTY-300型全自动图像分析仪测量P53免疫组织化学染色阳性物质吸光度。结果:经补充后20只猪进入结果分析。①脊髓损伤后3h打击伤组伤点,火器伤组近伤段脊髓P53蛋白的表达高于空白对照组(P<0.001),随着时间推移,打击伤组和火器伤组P53蛋白的表达呈升高趋势(P<0.001),且火器伤组要高于打击伤组(P<0.0001)。②在脊髓损伤后6h,打击伤组仅在伤点和近伤段P53蛋白的表达高于空白对照组(5.57±0.82,3.21±0.43,P<0.05),而火器伤组近伤段、中伤段及远段伤均高于空白对照组(6.46±0.66,4.27±0.39,1.16±0.17,P<0.05)。结论:①细胞凋亡基因p53在脊髓损伤中的表达有一定的时空性,在脊髓损伤后3h出现P53蛋白表达量的增加。②脊髓火器伤的波及范围较打击伤更为广泛。 相似文献
92.
腰椎定点牵压与硬膜外隙注药疗法单独或联合应用治疗腰椎间盘突出症 总被引:1,自引:0,他引:1
目的:对比观察硬膜外隙注药与腰椎定点牵压疗法及其联合应用治疗腰椎间盘突出症的疗效。方法:①选择2004-01/2006-01解放军总医院康复医学科门诊诊治的腰椎间盘突出症患者180例,男125例,女55例,年龄20~65岁。患者对治疗方案知情同意。按随机数字表法将患者分为3组:硬膜外隙注药组、腰椎定点牵压疗法组、联合治疗组,每组60例。硬膜外隙注药组:骶管注射利多卡因注射液、胞二磷胆碱、维生素B12、地塞米松混合液,每5d注射1次,共4次。腰椎定点牵压疗法组:采用胸带与下肢固定带牵引,待牵引床启动逐渐使患者腰脊柱拉伸时,术者双手拇指关节突关节连线,由上腰段向腰骶段滑行推压,当拇指推压到病变间隙时,牵引力须达到患者体质量1.5倍左右,迅速向脊柱前方施压。共2次。联合治疗组为两种疗法联合应用。每2次硬膜外隙注药后施行腰椎定点牵压疗法疗法1次,共2次。②于治疗前和治疗后3,6个月采用疼痛强度评分评估疼痛程度(0~10分,0分为无痛,10分为最痛),治疗前和治疗后3个月观察临床体征和评估疗效,疗效评估依据胡有谷的腰椎间盘突出症和国家中医药管理局(1994年)制定的中医病症诊断疗效标准。③计量和计数资料差异比较分别采用t检验和χ2检验。结果:腰椎间盘突出症患者180例均进入结果分析。①疼痛强度变化:治疗后3个月3组疼痛强度评分均较治疗前降低,其中联合治疗组与治疗前比较,差异明显(χ2=2.13,P<0.01)。治疗后6个月,各组病例的疼痛症状大多数获得控制,其中联合治疗组疼痛强度评分与治疗前比较,差异明显(χ2=4.03,P<0.01),联合治疗组和硬膜外隙注药组疼痛强度评分明显低于腰椎定点牵压疗法组(χ2=5.62,6.16,P<0.05)。②临床体征变化:各组治疗后3个月4项体征均较治疗前改善,其中联合治疗组直腿抬高试验阳性患者数明显少于硬膜外隙注药组和腰椎定点牵压疗法组(7,19,14例,χ2=9.24,9.14,P<0.01)。③疗效:联合治疗组治疗有效率明显高于其他硬膜外隙注药组和腰椎定点牵压疗法组[100%(60/60),88%(53/60),92%(55/60),χ2=6.26,6.04,P<0.01],而其他2组间比较,差异不明显(χ2=8.63,P>0.05)。结论:硬脊膜外注药及腰椎定点牵压疗法均是治疗腰椎间盘突出症的有效疗法,联合应用疗效更好。 相似文献
93.
94.
95.
A two-color flow cytometry assay for detection of hairy cells using monoclonal antibodies 总被引:2,自引:0,他引:2
We have developed a simple two-color immunofluorescence assay equally suited for microscopy and flow cytometry detecting hairy cells (HCs) in single cell suspensions, based on the concomitant reactivities with the B cell-specific monoclonal antibody B1 (CD20) and the monocyte/HC- associated antibody SHCL-3 (CD11c). Thus, HCs can be demonstrated in peripheral blood, bone marrow, and spleen specimens from hairy cell leukemia (HCL) patients even when they constitute less than 1% of the cell suspension. Likewise, admixture experiments with normal mononuclear cells and the MOLT-4 T-acute lymphocytic leukemia (ALL) cell line demonstrated that HCs could be detected in amounts as low as 1%. The validity of this assay has been ascertained by the lack of double marker positivity in cell suspensions from B-chronic lymphocytic leukemia (CLL) and acute myelogenous leukemia (AML) patients that only expressed B1 or SHCL-3, respectively. Furthermore, other malignant blood diseases, including malignant lymphomas, acute leukemias, and chronic leukemias disclosed no double marker positive cells. In a clinical setting, this assay was used for purifying HCs (by flow cytometry) from the peripheral blood from patients with no apparent morphological evidence of circulating HC infiltration and for monitoring the effect of interferon therapy. In conclusion, this assay should be of value for both diagnosis and monitoring patients with HCL. 相似文献
96.
Granulocyte-macrophage colony-stimulating factor mRNA stabilization enhances transgenic expression in normal cells and tissues 总被引:2,自引:1,他引:2
To increase transgenic production of granulocyte-macrophage colony- stimulating factor (GM-CSF), we mutated the mRNA's 3'-untranslated region, AUUUA instability elements. Expression vectors containing human or murine GM-CSF cDNAs coding for wild-type (GM-AUUUA) or mutant versions with reiterated AUGUA repeats (GM-AUGUA) were transfected into cells in culture or animals using particle-mediated gene-transfer technology. Normal peripheral blood mononuclear cells accumulated 20- fold greater levels of GM-CSF mRNA and secreted comparably greater amounts of cytokine after transfection with hGM-AUGUA expression vectors versus hGM-AUUUA. hGM-AUGUA mRNA was fivefold more stable (t 1/2 = 95 minutes) than hGM-AUUUA mRNA (t 1/2 = 20 minutes), accounting for elevated steady-state levels. Transfection site extracts and serum samples obtained 24 hours after gene transfer of hGM-AUGUA cDNA into mouse skin contained greater than 32 ng/mL and 650 pg/mL of GM-CSF protein, respectively, compared with 0.33 ng/mL and less than 8 pg/mL for hGM-AUUUA cDNA. GM-CSF produced from mGM-AUGUA cDNA transfected into rat abdominal epidermis induced a profound neutrophil infiltrate. These data suggest a novel strategy for enhanced production of biologically active cytokines by normal cells after in vivo gene transfer. 相似文献
97.
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes. 相似文献
98.
Activated protein C resistance: molecular mechanisms based on studies using purified Gln506-factor V 总被引:6,自引:1,他引:6
Gln506-factor V (FV) was purified from plasma of an individual homozygous for an Arg506Gln mutation in FV that is associated with activated protein C (APC) resistance. Purified Gln506-FV, as well as Gln506-FVa generated by either thrombin or FXa, conveyed APC resistance to FV-deficient plasma in coagulation assays. Clotting assay studies also suggested that APC resistance does not involve any abnormality in FV-APC-cofactor activity. In purified reaction mixtures, Gln506-FVa in comparison to normal FVa showed reduced susceptibility to APC, because it was inactivated approximately 10-fold slower than normal Arg506-FVa. It was previously reported that inactivation of normal FVa by APC involves an initial cleavage at Arg506 followed by phospholipid- dependent cleavage at Arg306. Immunoblot and amino acid sequence analyses showed that the 102-kD heavy chain of Gln506-FVa was cleaved at Arg306 during inactivation by APC in a phospholipid-dependent reaction. This reduced but measurable susceptibility of Gln506-FVa to APC inactivation may help explain why APC resistance is a mild risk factor for thrombosis because APC can inactivate both normal FVa and variant Gln506-FVa. In summary, this study shows that purified Gln506- FV can account for APC resistance of plasma because Gln506-FVa, whether generated by thrombin or FXa, is relatively resistant to APC. 相似文献
99.
Weisdorf DJ; Verfaillie CM; Davies SM; Filipovich AH; Wagner JE Jr; Miller JS; Burroughs J; Ramsay NK; Kersey JH; McGlave PB 《Blood》1995,85(12):3452-3456
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
100.
The epidemiology of hyperuricaemia and gout in Taiwan aborigines 总被引:4,自引:1,他引:4
To determine the prevalence of hyperuricaemia, gout and gout-related
factors in Central Taiwan Atayal aborigines, 342 subjects over 18 yr old
were interviewed and examined. A questionnaire was designed to screen for
signs and symptoms of gout and gout-related risk factors. Serum uric acid,
triglyceride and creatinine were measured in all subjects. The prevalence
of hyperuricaemia was 41.4% and that of gout 11.7% in aborigines. The uric
acid level was 7.9+/-1.7 mg/dl in males and 5.7+/-1.5 in females, and
differed significantly under age 70 yr (P < 0.001). Significantly
increased triglyceride, creatinine and alcoholism was found in gouty
patients compared with non-gouty patients. In 40 cases with gout, 54% had
tophi and 35% of their first- degree relatives had gout. The high
prevalence of hyperuricaemia and gout in Taiwan Atayal aborigines, a
significant family predisposition, increased creatinine level and
alcoholism suggest multiple factors affecting the hyperuricaemia.
相似文献