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61.
62.
EM Sloand  ; HG Klein 《Transfusion》1990,30(4):333-338
White cells (WBCs) present in stored platelet concentrates have adverse effects on platelet function and on posttransfusion recovery. Although these effects have been attributed to the fall in pH that results from active WBC metabolism, platelets stored in gas-permeable storage bags still exhibit abnormalities, despite maintenance of a stable pH of greater than 6.0. The changes in platelet proteins and function brought about by storage with a controlled number of WBCs were studied. Twelve platelet-pheresis specimens were centrifuged at 180 x g to achieve a WBC count of less than 2 x 10(5) per mL (which contained less than 10% granulocytes). These specimens were split into two aliquots and placed in platelet bags for storage at 22 degrees C with constant horizontal agitation. Neutrophils, obtained from the same donor by centrifugation of 50 mL of whole blood through a discontinuous ficoll gradient, were added to one of the two platelet storage bags to achieve a final neutrophil count of 1 x 10(6) per mL. Platelet aliquots were removed and studied on Days 3 and 5. In platelets stored without neutrophils, the average response to ristocetin, using the mean slope as an index of platelet responsiveness, was 10.3 (n = 9, SD = 11) on Day 3, whereas for the platelets stored with neutrophils, it was 1.25 (n = 12, SD = 0.9, p less than 0.01). Significant differences were also seen on Day 5 (slope = 4.5 for platelets stored without neutrophils, slope = 0.3 for platelets stored with neutrophils, p less than 0.01). Platelet aggregation with 8 microM ADP and 1.5 mg per mL of collagen did not differ significantly.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
白介素与溃疡性结肠炎   总被引:17,自引:1,他引:17  
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关.  相似文献   
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Atherosclerosis is associated with oxidative stress and inflammation, and upregulation of LOX-1, an endothelial receptor for oxidized LDL (oxLDL). Here, we describe generation of LOX-1 knockout (KO) mice in which binding of oxLDL to aortic endothelium was reduced and endothelium-dependent vasorelaxation preserved after treatment with oxLDL (P<0.01 versus wild-type mice). To address whether endothelial functional preservation might lead to reduction in atherogenesis, we crossed LOX-1 KO mice with LDLR KO mice and fed these mice 4% cholesterol/10% cocoa butter diet for 18 weeks. Atherosclerosis was found to cover 61+/-2% of aorta in the LDLR KO mice, but only 36+/-3% of aorta in the double KO mice. Luminal obstruction and intima thickness were significantly reduced in the double KO mice (versus LDLR KO mice). Expression of redox-sensitive NF-kappaB and the inflammatory marker CD68 in LDLR KO mice was increased (P<0.01 versus wild-type mice), but not in the double KO mice. On the other hand, antiinflammatory cytokine IL-10 expression and superoxide dismutase activity were low in the LDLR KO mice (P<0.01 versus wild-type mice), but not in the double KO mice. Endothelial nitric oxide synthase expression was also preserved in the double KO mice. The proinflammatory signal MAPK P38 was activated in the LDLR KO mice, and LOX-1 deletion reduced this signal. In conclusion, LOX-1 deletion sustains endothelial function leading to a reduction in atherogenesis in association with reduction in proinflammatory and prooxidant signals.  相似文献   
66.
Seventy-four patients with necrotizing pancreatitis were included in a prospective clinical trial of a surgical management protocol comprising necrosectomy and postoperative local lavage of the lesser sac and of the necrosis cavity. Fifty-eight patients showed preoperative organ failures such as pulmonary dysfunctions (57%), renal dysfunctions (37%), shock (12%), and sepsis (26%) in spite of intensive care treatment. The median value of the early prognostic signs was 4.5 points. Intraoperatively, 62% of the patients revealed extensive intrapancreatic parenchymal necrosis, 69% had extrapancreatic necrosis, and 39% showed bacterial contamination of the necrotic material. Following the necrosectomy, postoperative local lavage was performed for an average period of 25 days with 7 liters (median) of lavage fluid per 24 hours. In each of 18 studied patients, a considerable release of immunoreactive trypsin was demonstrated and, in each of 20 studied patients, a high concentration of immunoreactive phospholipase A2 was demonstrated in the lavage fluid up to the 12th/14th postoperative day. The intensive care period averaged 6 1/2 days, the hospital stay averaged 54 days. The hospital mortality rate was 8.1%. It is concluded that restricted necrosectomy and postoperative local lavage treatment correspond in particular to the pathomorphologic conditions and to the local release of biologically active compounds such as bacteria, endotoxin, trypsin, and phospholipase A2 in patients with necrotizing pancreatitis.
Resumen Setenta y cuatro pacientes con pancreatitis necrotizante fueron incluídos en un ensayo clínico prospectivo aplicando un protocolo de manejo quirÚrgico que comprende necrosectomía y lavado peritoneal postoperatorio de la transcavidad de los epiplones y de la cavidad necrótica. Cincuenta y ocho pacientes exhibierion fallas orgánicas postoperatorias tales como disfunción pulmonar (57%), disfunción renal (37%), shock (12%), y sepsis (26%) a pesar de cuidado intensivo. El valor promedio de los signos précoces pronóstico (Ranson), con exclusión de la retención de líquido fue de 4.5 puntos. Los hallazgos intraoperatorios revelaron necrosis pancreática extensa en 62% de los pacientes, necrosis extrapancreática en 69%, y contaminación bacteriana del material necrótico en 39%. Realizada la necrosectomía se instauró lavado peritoneal postoperatorio por un período promedio de 25 días con 7 litros (promedio) de líquido por cada 24 horas. En cada uno de los 18 pacientes estudiados se demostró liberación considerable de tripsina inmunorreactiva, así como una elevada concentración de fosfolipasa A2 inmunorreactiva, en el líquido de lavado hasta el 12/14 días postoperatorios. El período de cuidado intensivo fue de 6 1/2 días, y la hospitalización de 54 días en promedio. La mortalidad hospitalaria fue de 8.1%. En conclusión, se plantea que el tratamiento mediante la necrosectomía restringida y el lavado peritoneal local postoperatorio está indicado en pacientes con las condiciones patomorfológicas de pancreatitis necrotizante que resultan en la liberación local de compuestos biológicamente activos tales como bacterias, endotoxina, tripsina, y fosfolipasa A2. Serán necesarios ulteriores estudios clínicos controlados para confirmar los resultados favorables que hemos obtenido con la necrosectomía y el lavado peritoneal postoperatorio en pacientes con pancreatitis necrotizante y extensa e infectada necrosis pancreática.

Résumé Un essai prospectif d'une méthode de traitement chirurgical consistant en nécrosectomie associée au lavage de l'arrière cavité des épiploons et de la cavité nécrotique a concerné 74 malades présentant une pancréatite nécrotique. Malgrè le traitement intensif 58 d'entre eux ont accusé des complications telles que troubles pulmonaires (57%), rénaux (37%), choc (12%), et infection (26%). La valeur moyenne des signes de pronostic précoce fut de 4.5 points. A l'intervention 62% des opérés présentaient une nécrose pancréatique étendue, 69% des opérés une nécrose extra-pancréatique, 39% une surinfection du tissu pancréatique. Après l'exèrése de la nécrose le lavage fut pratiqué quotidiennement avec en moyenne 7 litres de liquide pendant une période de 25 jours. Chez 18 malades fut constaté une libération importante de trypsine immunoactive et chez 20 malades un taux élevé de phospholipase cA dans le liquide de lavage pendant 12/14 jours après l'intervention. La durée des soins intensifs fut en moyenne de 6.5 jours et celle de l'hospitalisation de 54 jours. Le taux de mortalité opératoire fut de 8.1%. On peut conclure de ces faits que la nécrosectomie limitée, associée au lavage local constitue un traitement adapté aux lésions et à la libération locale d'éléments biologiques pathologiques: bactérie, endotoxine, trypsine, et phospholipase A au cours de la pancréatite nécrotique.
  相似文献   
67.
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BACKGROUND/AIMS: Recently we have shown that NSC-631570 (Ukrain) is a safe and effective drug in the treatment of unresectable pancreatic cancer. The aim of this study was to determine the effectiveness of the combined treatment with Gemcitabine and NSC-631570 in the adjuvant treatment of resected advanced pancreatic cancer. METHODOLOGY: 30 patients received adjuvant chemotherapy following surgical resection for pancreatic cancer. Chemotherapy consisted of Gemcitabine according to the Burris-protocol with weekly infusions of 1000 mg/sqm. Immediately following Gemcitabine infusion 20mg of NSC-631570 were administered intravenously over 15 minutes. RESULTS: WHO grade II toxicities were observed in 53%, no WHO grade III or IV toxicities occurred. In 80% of the patients recurrence of the disease was observed. The relapse-free survival time was 21.7 months. The actuarial survival rates were 86.7% after one year, 76.6% after two years, 46.7% after three years and 23.3% after five years. The median survival time according to Kaplan-Meier regression analysis was 33.8 months. CONCLUSIONS: Adjuvant chemotherapy in advanced stages of pancreatic cancer using the combination of Gemcitabine and NSC-631570 is a safe treatment and seems to lead to a prolonged survival. Although further investigation is needed to confirm these results, the combined treatment of Gemcitabine and NSC-631570 is a promising therapy for the adjuvant treatment of resectable advanced pancreatic cancer.  相似文献   
69.
Early severe acute pancreatitis: characteristics of a new subgroup   总被引:57,自引:0,他引:57  
Isenmann R  Rau B  Beger HG 《Pancreas》2001,22(3):274-278
This study focuses on patients with severe acute pancreatitis complicated by organ failure within the initial phase of the disease. Data of 158 patients with severe acute pancreatitis (SAP) admitted to hospital within 72 hours after onset of symptoms were prospectively documented and analyzed for the occurrence of early severe acute pancreatitis (ESAP). ESAP was defined as presence of organ failure (OF) at admission. Forty-seven (30%) patients had ESAP, compared with 111 patients without OF (SAP group). In a multivariate analysis, the main factor predisposing to ESAP was the presence of extended pancreatic necrosis (odds ratio, 3.8), whereas biliary pancreatitis was associated with a slightly lower risk compared with alcoholic pancreatitis (odds ratio, 0.34). Compared with SAP, patients with ESAP more frequently developed intractable organ failure, which posed the indication for surgical treatment. Surgical necrosectomy due to progressive OF had to be performed in 89% of the ESAP patients and in 60% of the SAP patients. The incidence of infected pancreatic necrosis did not differ between both groups (23 vs. 21%). Mortality was significantly higher in ESAP (42 vs. 14%; p = 0.0003). ESAP is characterized by the presence of extended pancreatic necrosis and a complicated clinical course. Intractable organ failure is a frequent finding. Given the poor prognosis of ESAP, these patients should be treated in specialized intensive care units.  相似文献   
70.
BACKGROUND/AIMS: Small interfering RNAs (siRNAs) are an efficient tool to specifically inhibit gene expression by RNA interference. Since hepatitis C virus (HCV) replicates in the cytoplasm of liver cells without integration into the host genome, RNA-directed antiviral strategies are likely to successfully block the HCV replication cycle. Additional benefit might arise from inhibition of cellular cofactors of HCV replication, such as proteasome alpha-subunit 7 (PSMA7) or Hu antigen R (HuR). METHODS: In this study, we investigated direct and cofactor-mediated inhibition of HCV by a panel of DNA-based retroviral vectors expressing siRNAs against highly conserved HCV sequences or the putative HCV cofactors PSMA7 and HuR. Effects were determined in HCV IRES-mediated translation assays and subgenomic HCV replicon cells. RESULTS: PSMA7- and HuR-directed siRNAs successfully inhibited expression of the endogenous genes, and PSMA7 and HuR silencing significantly diminished HCV replicon RNA and NS5B protein levels. HCV-directed siRNAs substantially inhibited HCV IRES-mediated translation and subgenomic HCV replication. Combinations of PSMA7- and HuR-directed siRNAs with HCV-directed siRNAs revealed additive HCV RNA inhibitory effects in monocistronic replicon cells. CONCLUSIONS: A dual approach of direct- and cofactor-mediated inhibition of HCV replication might avoid selection of mutants and thereby become a powerful strategy against HCV.  相似文献   
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