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951.
Jocivania O da Silva Renata S Fernandes Fábio K Ticli Clayton Z Oliveira Maurício V Mazzi Jo?o J Franco Silvana Giuliatti Paulo S Pereira Andreimar M Soares Suely V Sampaio 《Toxicon》2007,50(2):283-291
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies. 相似文献
952.
Platelet function in patients with acute coronary syndrome (ACS) predicts recurrent ACS 总被引:2,自引:0,他引:2
I. FUCHS† M. FROSSARD† A. SPIEL E. RIEDMÜLLER† A. N. LAGGNER† B. JILMA 《Journal of thrombosis and haemostasis》2006,4(12):2547-2552
BACKGROUND: Platelet hyperfunction contributes to acute coronary syndromes (ACS). Thus, we hypothesized that platelet function under high shear stress predicts recurrent ACS during long-term follow-up of ACS patients. PATIENTS AND METHODS: Consecutive ACS patients (n = 208) were prospectively followed-up for an average of 28 months. Platelet function was measured with the platelet function analyzer (PFA-100; Dade Behring, Marburg, Germany) at baseline for collagen/adenosine diphosphate closure times (CADP-CT) and for collagen/epinephrine closure times (CEPI-CT) after infusion of a uniform dose of 250 mg aspirin. RESULTS: Of the conventional risk factors, only the prevalence of diabetes was higher in ACS patients with re-events. However, use of clopidogrel and use of beta blockers were also slightly lower in patients with re-events (P < 0.05). The unadjusted risk hazard ratio (HR) for re-events was 3.3 [95% confidence interval (95% CI): 1.4-7.4; P = 0.005] in those patients with the shortest CADP-CT values (lowest quartile). Similarly, the risk was 2.0-fold higher (95% CI: 1.1-3.6; P = 0.02) in ACS patients with CEPI-CT < 300 s as compared with CEPI-CT >or = 300 s. Inclusion of diabetes, clopidogrel and beta blockers in a multivariate Cox regression model enhanced the predictive value of CEPI-CT (HR: 2.7). Inclusion of von Willebrand factor levels did not alter the HR for recurrent ACS (HR: 2.1; 95% CI: 1.1-5.2; P = 0.03) for CEPI-CT < 300 s, but reduced the HR for CADP-CT (HR: 2.8, 95% CI: 0.8-9.8; P = 0.11). CONCLUSION: Shortened CT values reflect biologically relevant platelet hyperfunction in patients with ACS because they predict recurrent ACS. 相似文献
953.
前列腺癌中PIM-1的表达及其临床意义 总被引:4,自引:0,他引:4
目的 探讨PIM-1在前列腺癌中的表达及临床意义。方法 逆转录-聚合酶链反应(RT—PCR)半定量分析2例良性前列腺增生(BPH)和5例前列腺癌(PCa)组织标本中PIM-1mRNA表达,免疫组织化学法检测20例BPH、20例高分级前列腺上皮内瘤(HGPIN)和42例PCa组织标本中PIM-1蛋白表达水平,染色结果分为阴性、弱阳性、阳性和强阳性。结果 5例PCa组织PIM-1mRNA表达相对值分别为0.63、0.55、0.42、0.91、0.76,2例BPH中其相对值为0.26、0.27。BPH、HGPIN和PCa组织中PIM-1蛋白阴性表达率分别为60%(12/20)、20%(4/20)和2%(1/42),弱阳性表达率分别为40%(8/12)、20%(4/20)和12%(5/42),阳性列强阳性表达率分别为0(0/20)、60%(12/20)和86%(36/42),PCa中PIM-1蛋白表达水平高于HGPIN和BPH(P值均〈0.05)。PIM-1蛋白表达水平随PCa的临床分期和病理分级增高而增强,在有和没有淋巴结转移PCa组织中PIM-1强阳性表达率分别为70%(7/10)、25%(8/32),差异有统计学意义(P〈0.05)。结论PIM-1高表达可能与PCa发生和发展相关,PIM-1表达水平与PCa分期、Gleason评分呈正相关,可能成为PCa预后判断的肿瘤标志物。 相似文献
954.
肾结核40例临床分析 总被引:1,自引:1,他引:0
目的 分析6年来肾结核的临床表现和诊断方法。方法回顾性分析近6年收治的40例肾结核患者的临床资料。结果表现为膀胱刺激征的典型肾结核占65%,不典型肾结核占35%,其临床症状以腰痛、血尿为主。所有患者尿常规均异常。B超、静脉尿路造影(IVU)、逆行肾盂造影(RP)、磁共振尿路水成像(MRU)确诊率分别为20%、55%、66.7%和77.8%。结论膀胱刺激征仍是肾结核的主要临床表现,不典型肾结核有所增加。IVU是首选诊断方法,MRU对晚期肾结核诊断具有重要价值。 相似文献
955.
956.
目的 探讨脂质体(liposome)介导转录因子NF—κB诱捕物(decoy)寡聚脱氧核苷酸(oligodeoxynucleotide,ODN)对重症急性胰腺炎SD大鼠肺部NF-κB活性及受其调控炎症基因mRNA表达和肺损伤的影响。方法 以牛磺胆酸钠(STC)诱导SD大鼠建立重症急性胰腺炎模型,以假手术组为对照组,于建模后1h分别静脉注射裸ODN、脂质体/decoy ODN复合物、脂质体/scrambled ODN复合物和生理盐水,注射4h后应用电泳迁移率变动(EMSA)分析NF-κB的活性,利用逆转录-聚合酶链反应法(RT-PCR)检测肺组织ICAM-1、IL-1α、IL-2、TNF—α、VCAM-1mRNA表达,同时检测氧分压、肺组织湿/干重比率和肺组织髓过氧化物酶(MPO)。结果 EMSA显示脂质体/decoy ODN复合物组NF—κB活性明显低于生理盐水组、脂质体/scrambled ODN复合物组和裸ODN组(P〈0.05),RT—PCR显示脂质体/decoy ODN复合物组ICAM-1、IL-1α、IL-2、TNF—α、VCAM-1mRNA表达小于生理盐水组、脂质体/scrambled ODN复合物组和裸ODN组(P〈0.05)。与生理盐水组、脂质体/scrambled ODN复合物组和裸ODN组相比,脂质体/decoy ODN复合物组动脉血氧分压升高,肺组织湿/干重比率和肺组织髓过氧化物酶(MPO)活性降低(P〈0.05)、结论 NF—κB decoy ODN可特异性抑制肺NF-κB活性及其调控的炎症因子ICAM-1、IL—1α、IL-2、TNF-α、VCAM-1mRNA的表达,减轻肺损害。 相似文献
957.
Yoshimasa Sakamoto Kazuhiro Hashimoto Hiroshi Okuyama Shinichi Ishii Takahiro Inoue Katsushi Kinouchi Takayuki Abe 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(9):465-469
Objective The objective of the present study was to compare long-term results of single aortic valve replacement (AVR) with mechanical
(St. Jude Medical valves: standard) and biologic (the Carpentier-Edwards pericardial) prostheses. Method: Between 1995 and 2002, 95 patients who underwent single AVR with mechanical (n=46) or biologic (n=49) prostheses were enrolled
in this study. The mean age at the operation was 54.0±9.6 years (range: 20 to 69 years) with the mechanical and 68.8±7.1 years
(range: 44 to 85 years) with the biologic prosthesis. Results: The 9-year actuarial survival rate, which was calculated by taking perioperative mortality into account, was 90.3±4.6% for
patients with mechanical valves and 87.6 ±4.8% for patients with bioprostheses, with no difference between the two groups
(p=0.342). The 9-year freedom rate from thromboembolism, reoperation, endocarditis was 94.8+3.6%, 100% and 97.8 ±2.2% for
patients with mechanical valves and 98.0 ±2.0%, 97.5 ±3.4% and 95.0 ±3.4% for those with bioprostheses, respectively. After
9 years, freedom from cardiac death averaged 97.8% in the group with mechanical valves compared with 95.3% in those with bioprostheses
(p=0.541). Conclusion: We conclude that the mid-term durability of the Carpentier-Edwards pericardial valve in the aortic position for the elderly
is excellent. Nevertheless, the risk of tissue valve reoperation progressively increases with time, and a longer follow-up
may be necessary to provide its value compared with the mechanical valves in a country like Japan with a high life expectancy.
(Jpn J Thorac Cardiovasc Surg 2005; 53:465-469) 相似文献
958.
目的了解ret/PTC基因突变与超声、病理诊断在甲状腺乳头状癌诊断中的关系。方法术前超声检查,并在超声引导下细针穿刺,活体取材进行病理诊断和逆转录聚合酶链(RT-PCR)方法检测ret/PTC基因突变。结果在34例超声与病理诊断的甲状腺乳头状癌(PTC)患者中,16例分子生物学检测发现ret/PTC基因突变(47%),其中8例为PTC-1基因突变(50%),2例PTC-2基因突变(12.5%),2例PCT-3基因突变(12.5%),3例PTC-1和PTC-2突变同时存在(18.75%),1例PTC-1和PTC-3突变同时存在(6.25%)。结论ret/PTC基因重组突变可存在于散发的甲状腺乳头状癌中,主要表现PTC-1型。应用超声引导下细针穿刺与甲状腺乳头状癌基因突变的检测相结合是早期诊断甲状腺乳头状癌的有效方法。 相似文献
959.
目的研究三氧化二砷(As2O3)诱导人肝癌细胞系Bel-7402细胞凋亡及与线粒体跨膜电位的关系。方法应用不同浓度的As2O3作用于肝癌细胞后,观察As2O3对肝癌细胞生长状态的影响;通过噻唑蓝(MTT)比色法观察其对Bel-7402细胞增殖的影响;利用共聚焦显微镜及流式细胞术观察经Annexin V-FITC/PI双染后的细胞早期凋亡;通过共聚焦显微镜及流式细胞仪检测线粒体跨膜电位(MMP)的改变情况;并通过底物染色法反映Caspase-3的活性。结果不同浓度的As2O3作用于肝癌细胞后有明显的时间和剂量依赖性;经Annexin V-FITC/PI双染后,可观察到Bel-7402细胞的早期凋亡现象,2μmol/L As2O3作用24h细胞凋亡率为9.89%,作用48h细胞凋亡率为48.53%,而4μmol/L As2O3作用24h细胞凋亡率为18.27%,作用48h细胞凋亡率为67.52%;经As2O3药物作用后,细胞线粒体膜电位水平下降,且与药物作用时间和药物浓度有关(P〈0.05);同时Caspase-3活性被激活。结论As2O3可明显抑制肝癌细胞Bel-7402的生长,并使细胞线粒体膜电位下降,诱导肝癌细胞凋亡。 相似文献
960.
Fahim Zaman Atta Nawabi Kenneth D Abreo Gazi B Zibari 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(3):262-265
Laparoscopic procedures continue to gain popularity over traditional open procedures for a number of abdominal and pelvic surgeries. With increasing experience, the application of this technique is rising because it provides an alternative, less invasive, approach to various surgical procedures. Herein, we report our experience with adult patients with polycystic kidney disease, requiring bilateral laparoscopic nephrectomy before renal transplantation. 相似文献