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1.

Background

Ischemia–reperfusion injury induced by pneumoperitoneum is a well-studied entity, which increases oxidative stress during laparoscopic operations. The reported anti-inflammatory action of aprotinin was measured in a pneumoperitoneum model in rats for the first time in this study.

Materials and methods

A total of 60 male Albino Wistar rats were used in our protocol. Prolonged pneumoperitoneum (4 h) was applied, causing splanchnic ischemia and a period of reperfusion with a duration of 60 or 180 min followed. Several cytokines and markers of oxidative stress were measured in liver, small intestine, and lungs to compare the aprotinin group with the control group. Tissue inflammation was also evaluated and compared between groups using a five-scaled histopathologic score.

Results

In aprotinin group values of biochemical markers (tumor necrosis factor α, interleukin 6, endothelin 1, C reactive protein, pro-oxidant–antioxidant balance, and carbonyl proteins) were lower in all tissues studied. Statistical significance was greater in liver and lungs (P < 0.05). Histopathologic examination revealed significant difference between control and aprotinin groups in all tissues examined. Aprotinin groups showed mild to moderate lesions, while in control groups severe to very severe inflammation was present. Aprotinin subgroup with prolonged reperfusion period (180 min) showed milder lesions in all tissues than the rest of the groups.

Conclusions

Aprotinin reduced inflammatory response and oxidative stress induced by pneumoperitoneum in liver, small intestine, and lungs.  相似文献   
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Digital imaging of the chest   总被引:4,自引:0,他引:4  
During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.  相似文献   
6.
Background: The use of ozone therapy in the treatment of dental caries is equivocal. The aim of this study was to use an in vitro model to determine the effects of prior ozone application to dentine on biofilm formation and to measure any associated reduction in bacteria viability. Methods: Twenty dentine discs were bonded to the bases of 5 mL polycarbonate screw top vials. Ten dentine discs were infused with ozone for 40 seconds, 10 samples remained untreated as a control. The vials were filled with nutrient medium, sterilized and placed into the outflow from a continuous chemostat culture of Streptococcus mutans and Lactobacillus acidophilus for four weeks. At the conclusion of the experiment bacterial growth was monitored by taking optical density readings of the growth medium in each vial and the outer surface of the dentine specimens were examined by scanning electron microscopy as shown by SEM analysis. Results: Ozone infusion prevented biofilm formation on all the treated samples while there was substantial biofilm present on the control specimens. While the average optical density of the control specimens was almost twice that of the ozone infused dentine (0.710 for the control with a SD of 0.288 and 0.446 for the ozonated samples with a SD of 0.371), the results were not significant (p > 0.05). Conclusions: This preliminary study has shown that the infusion of ozone into non‐carious dentine prevented biofilm formation in vitro from S. mutans and L. acidophilus over a four‐week period. The possibility exists that ozone treatment may alter the surface wettability of dentine through reaction with organic constituents.  相似文献   
7.
Ball  ED; Mills  LE; Coughlin  CT; Beck  JR; Cornwell  GG d 《Blood》1986,68(6):1311-1315
Second or third chemotherapy-induced remissions in acute myelogenous leukemia (AML) are limited by early relapse of the leukemia. We developed monoclonal antibodies (MoAbs) that are cytotoxic to myeloid leukemia cells to treat bone marrow from these patients ex vivo for autologous transplantation. In this pilot study, bone marrow was harvested from ten patients with AML in remission, treated with one or two complement-fixing MoAbs, PM-81 and AML-2-23, which react with myeloid differentiation antigens, incubated with rabbit complement, and cryopreserved. These MoAbs were chosen because they have broad reactivity with AML cells but not with pluripotent progenitor cells. At the time of transplant, 6 patients were in second complete remission, 1 each was in third complete or partial remission, and 2 were in early first relapse. The patients were treated with cyclophosphamide (60 mg/kg a day for 2 days) and total body irradiation (200 cGy twice a day for 3 days) and given infusions of MoAb-treated bone marrow. Full bone marrow reconstitution was observed in eight patients; two patients did not recover platelets. Seven of the ten patients are surviving and disease-free at 21.0, 15.0, 13.0, 10.0, 6.0, 3.0, and 2.0 months posttransplant. Treating bone marrow with MoAbs to myeloid differentiation antigens does not interfere with pluripotential stem cell engraftment. Longer follow-up and a controlled study are necessary to prove that the apparent efficacy of this therapeutic approach in some patients is attributable to MoAb-mediated killing of leukemia cells.  相似文献   
8.
Taylor  KJ; Morse  SS; Weltin  GG; Riely  CA; Flye  MW 《Radiology》1986,159(2):357-363
Twenty patients, aged 4 months to 58 years, were evaluated for liver transplantation by duplex sonography, and 15 transplantations were completed; 42 postoperative examinations were performed. Sonographic findings were correlated with seven preoperative and five postoperative angiographic evaluations. Preoperative duplex US findings included tumors, portal vein occlusion, varices, biliary obstruction, and variant vascular anatomy. Postoperative findings included hepatic artery occlusion, portal vein occlusions (one with cavernous transformation), portal vein stenosis, biliary obstruction, intrahepatic and extrahepatic fluid collections, and air in the portal vein due to ischemic bowel. Use of angiography allowed confirmation of the vascular abnormalities and demonstrated evidence of rejection in patients with normal Doppler waveforms. Duplex sonography is a valuable portable technique for evaluating these patients and can be used in triage of patients requiring angiography.  相似文献   
9.
Cardiovascular risk factors in young snuff-users and cigarette smokers   总被引:4,自引:2,他引:2  
We studied cardiovascular risk factors in 21 young men who were habitual snuff-users, and compared them with the same risk factors in 18 non-tobacco-users and 19 cigarette smokers of the same age and body mass index. Both snuff-users and smokers showed increased levels of alcohol and coffee consumption and a decreased level of physical exercise compared to non-users. Both groups of tobacco-users showed increased serum insulin levels compared to the control group at similar blood glucose concentrations. In contrast to the smokers, snuff-users showed no significant elevation of diastolic blood pressure, haemoglobin concentrations, white cell count, serum cholesterol or triglyceride levels. Snuff users had higher plasma fibrinogen levels than non-users (P = 0.07). The use of snuff by young men appears to have less impact than smoking on cardiovascular risk factors, with the possible exception of elevated serum insulin and plasma fibrinogen levels.  相似文献   
10.
Blastomyces dermatitidis is a dimorphic fungus endemic to northwestern Ontario, Manitoba and some parts of the United States. The fungus is also endemic to parts of Africa. Pulmonary and extrapulmonary findings of a 24-year-old African man who presented with weight loss, dry cough and chronic pneumonia not resolving with antibiotic treatment are presented. The unusual occurrence of pulmonary blastomycosis associated with skin lesions and a moderate pleural effusion is reported.  相似文献   
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