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排序方式: 共有1201条查询结果,搜索用时 15 毫秒
991.
Transmission of serologically silent hepatitis B virus along with hepatitis C virus in two cases of posttransfusion hepatitis 总被引:1,自引:0,他引:1
I Baginski ; I Chemin ; O Hantz ; C Pichoud ; AM Jullien ; JC Chevre ; JS Li ; L Vitvitski ; JJ Sninsky ; C Trepo 《Transfusion》1992,32(3):215-220
The polymerase chain reaction (PCR) was used to investigate the presence of hepatitis B virus (HBV)-related DNA sequences in blood from three blood donors and two transfusion recipients who developed posttransfusion non-A, non-B hepatitis (NANBH). In the first case, the sole donor was positive for antibody to hepatitis B surface (HBs) and core (HBc) antigens and had elevated alanine aminotransferase (ALT) levels, while the recipient had no HBV serologic markers. Both the donor and the recipient had serologic markers of hepatitis C virus (HCV) and were found positive for HBV DNA and HCV RNA sequences by PCR. The second case involved two donors and one recipient. Serologic tests for conventional HBV markers were negative in all three individuals, but one of the donors had elevated ALT. HBV DNA sequences were detected by PCR in the serum of the recipient and of the donor with high ALT, but not in the serum of the donor with normal ALT. Anti-HCV was detected in the serum of the recipient and of the suspect donor but not in that of the donor with normal ALT. The sequences amplified in the S region and determined after cloning of PCR products for both donor-recipient pairs were indistinguishable from each other and identical to the sequence of the major HBV subtype of adw in the first case and ayw in the second case. Furthermore, for the second case, an identical single-point mutation was found in both the donor and the recipient. These data confirm the transmission of conserved HBV sequences together with HCV in posttransfusion NANBH.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
993.
BACKGROUND: The DUET Study is a multicenter prospective efficacy and safety evaluation of the ACS MULTI-LINK DUET coronary stainless steel balloon-expandable stent. AIMS: The primary objective was to determine the one-month incidence of MACE (major adverse cardiac events). The secondary objectives were the acute success rate, the restenosis and reocclusion rates (assessed by quantitative coronary angiography (QCA)) at six months and the occurrence of MACE in hospital and at six months. METHODS: Two hundred and ten patients were enrolled between February and June 1998 in 18 European centers. Successful stent placement was achieved in 209 patients. All patients were treated with ticlopidine 500 mg/day for one month and with aspirin S 100 mg/day. To allow the investigators to gain familiarity with the stent system, the first one to three patients per center formed a separate lead-in population leaving an intention-to-treat population of 157 patients. population were male (79%); 28% had unstable angina, 69% had stable angina, 44% had had a previous myocardial infarction, 15% had had a previous percutaneous transluminal coronary angioplasty, and 3% had a history of stroke. The target vessel was 38.5% left anterior descending artery, 20.5% left circumflex artery and 41.0% right coronary artery. RESULTS: All but one of the intention-to-treat patients were effectively stented (17 required multiple stents). Six-month angiographic follow-up was available in 90% of the intention-to-treat population. Minimal lumen diameter (MLD) postprocedure was 2.61 - 0.33 mm, with a residual diameter stenosis of 16%. Six-month follow-up data showed an MLD of 1.87 - 0.56 mm with a residual diameter stenosis of 36%. The binary restenosis rate ( S 50% residual stenosis) was 15.6%. Up to one month following the procedure 94.9% of the population was MACE-free, with two subacute occlusions. At six months all patients were alive, of whom 82.8% were MACE-free, and 73% were free of anginal complaints. CONCLUSION: The results observed in the current DUET registry are comparable to The majority of the intention-to-treat data of other balloon-expandable-stent trials, with a low incidence of clinical events at follow-up. (Int J Cardiovasc Intervent 2000; 3: 97-104) 相似文献
994.
P Chiari G Hadour P Michel V Piriou C Rodriguez C Budat M Ovize O Jegaden J J Lehot R Ferrera 《The Journal of heart and lung transplantation》2000,19(7):675-682
BACKGROUND: The physiopathology of hemodynamic instability that occurs after brain death remains unknown. The aim of this study was to examine the initial response to brain death induction. METHODS: After anesthesia and monitoring, 16 pigs were randomized into a control group (C, n = 8) and a brain death group (BD, n = 8). We inflated a subdural catheter balloon to induce brain death. We analyzed hemodynamic and plasmatic biochemical data for 180 minutes after brain death induction. Energetic compounds were measured. We expressed the results in comparison with the C group. RESULTS: The C group remained stable. One minute after brain death, the Cushing reflex appeared, with a hyperdynamic response to plasma catecholamines levels increasing (norepinephrine and epinephrine, 3.1-fold, p = 0. 02, and 3.8-fold, p = 0.07, respectively). After a return to baseline, we recorded a second hyperdynamic profile 120 minutes later. At this time, a second peak of catecholamines appeared (6. 3-fold, p = 0.04, and 9.1-fold, p = 0.02, concerning norepinephrine and epinephrine). At the same time, we observed brief myocardial lactate production (+175%, p < 0.01), with a rise of troponine I (+64%, p = 0.03). The energetic index was similar in both groups: 0. 85 (+/-0.02) in the C group vs 0.87 (+/-0.02) in the BD group. CONCLUSIONS: In this model, biphasic plasmatic catecholamine release appears to primarily explain the physiopathology of the hemodynamic response to brain death induction. 相似文献
995.
996.
PURPOSE: To review the pharmacologic and pathophysiologic information necessary to prescribe beta-blockers (BB) in perioperative medicine. DATA SOURCE: Manual retrieval and electronic research of the literature using MEDLINE (key-words: anesthesia and beta- blocker; surgery and beta-blocker). DATA SYNTHESIS: Cardioselective BB inhibit preferentially beta-1 receptors, inducing a decrease in heart rate and cardiac inotropism leading to reduction of oxygen myocardial consumption. Non-cardioselective BB inhibit also beta-2 receptors, increasing bronchial and peripheral vascular resistances and uterine contractions. However, some BB are also vasodilators (carvedilol, celiprolol, labetalol). Contraindications to BB result logically from their pharmacological effects. Treatment with BB increases membrane beta-receptor density; this explains sympathetic overactivity observed during weaning of treatment. Since the discovery of propranolol in 1964, the use of BB has been controversial in anesthesia. Formerly, the adverse effects of partial sympatholysis during anesthesia and surgery were feared. However, since 1973, experimental and clinical data have suggested a protective hemodynamic effect. CONCLUSION: Continued administration of BB up to the time of anesthesia has been encouraged except in patients with signs of intolerance such as hypotension or excessive bradycardia. 相似文献
997.
998.
999.
1000.
2,4,6-三硝基苯磺酸诱导小鼠炎症性肠病模型的建立 总被引:1,自引:0,他引:1
目的:建立2,4,6-三硝基苯磺酸诱导的结肠炎动物模型,并分析其剂量效应。方法:实验于2006-05/09在南方医院消化内科研究所完成,选用SPF级雌性Balb/c小鼠50只,按随机数字表法分为5组,每组10只,对照组予以300g/L乙醇溶液灌肠1次;其他4组分别给予含25mg/kg,50mg/kg,100mg/kg,150mg/kg2,4,6-三硝基苯磺酸的300g/L乙醇溶液灌肠1次。各组于造模后3,7,21,28d各处死1只小鼠,观察结肠的大体形态。造模后21d观察各组小鼠结肠的病理组织切片,并检测中性粒细胞的髓过氧化物酶活性。结果:造模过程中50,100,150mg/kg2,4,6-三硝基苯磺酸组各死亡2,3,3只小鼠。①各组小鼠造模后的一般情况:对照组及25mg/kg2,4,6-三硝基苯磺酸组小鼠发生一过性的结肠机械损伤表现,出现便血等现象,但3~7d后开始缓解;而50~150mg/kg2,4,6-三硝基苯磺酸组小鼠出现便血,腹泻。②各组小鼠结肠的大体形态及病理组织学观察结果:对照组和25mg/kg2,4,6-三硝基苯磺酸组小鼠肠道在第7天时表现为无粘连,局部充血,肠壁不增厚,未见溃疡,于第3周时局部充血已好转;结肠病理切片大致正常。50~150mg/kg2,4,6-三硝基苯磺酸组小鼠肠道肉眼可见粘连,肠腔增大,充血水肿,溃疡形成,出现肠道增厚,病理切片见黏膜下层水肿,固有层炎症细胞浸润等现象,以上现象于造模4周后开始缓解。其中当2,4,6-三硝基苯磺酸剂量为100mg/kg时作用达到高峰。③各组小鼠的中性粒细胞髓过氧化物酶活性比较:50,100,150mg/kg2,4,6-三硝基苯磺酸组均显著高于对照组[(14.17±3.33,18.50±2.33,18.17±1.50,4.83±2.00)nkat/L,(P<0.01)]。结论:应用含100mg/kg2,4,6-三硝基苯磺酸的300g/L乙醇溶液灌肠是诱导小鼠结肠炎较为理想的方法。 相似文献