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941.
942.
OBJECTIVE: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with an inflammatory response caused by contact of blood with artificial surfaces of the extracorporeal circuit, ischemia-reperfusion injury, and release of endotoxin. The inflammatory reaction involves activation of complement leucocytes, and endothelial cells with secretion of cytokines, proteases, arachidonic acid metabolites, and generation of oxygen derived free radicals (OFR) by polymorphonuclear neutrophils (PMN). Although this inflammatory response to CPB often remains at subclinical levels, it can also lead to major organ dysfunction. A number of studies have demonstrated that treatment of patients with a high-dose (30 mg/kg) of corticosteroids (methylprednisolone) attenuates the CPB-induced SIR and improves the outcome of patients undergoing cardiac surgery. However, large doses of steroids can cause abnormal metabolic responses such as metabolic acidosis and hyperglycemia. In the present study, we examined the efficacy of low doses of methylprednisolone (5 and 10 mg/kg) to attenuate the CPB-induced inflammatory response, during and after heart operations. METHODS: Thirty-six adult patients undergoing cardiac surgery, were randomized into three groups: (1) control group: group A; (2) methylprednisolone, 5 mg/kg body weight: group B; and (3) methylprednisolone, 10 mg/kg body weight: group C. Plasma levels of the cytokines interleukin-6 (IL-6) and TNF-alpha were analyzed by enzyme-linked immunosorbent assay, before, during, and after CPB. OFR production was determined by cytofluorometry (FACS) at the same end points. RESULTS: No significant differences in age, body weight, CPB time, and cross-clamp time were observed among the three groups. CPB induced a marked increased in cytokine release and OFR generation. Low-dose of methylprednisolone (5 mg/kg) effectively reduced the increase in TNF-alpha and IL-6 secretion (P<0.05 compared to control group) after release of the cross-clamp. However, OFR generation was significantly reduced with a greater dose of methylprednisolone (10 mg/kg). CONCLUSIONS: The results indicate that a single low-dose of methylprednisolone (10 mg/kg) reduces the inflammatory reaction during and after CPB, by inhibition of proinflammatory cytokine release and OFR generation after release of the aortic cross-clamp.  相似文献   
943.
A successful boron neutron capture treatment (BNCT) of a patient with multiple liver metastases has been first given in Italy, by placing the removed organ into the thermal neutron column of the Triga research reactor of the University of Pavia. In Finland, FiR 1 Triga reactor with an epithermal neutron beam well suited for BNCT has been extensively used to irradiate patients with brain tumors such as glioblastoma and recently also head and neck tumors. In this work we have studied by MCNP Monte Carlo simulations, whether it would be beneficial to treat an isolated liver with epithermal neutrons instead of thermal ones. The results show, that the epithermal field penetrates deeper into the liver and creates a build-up distribution of the boron dose. Our results strongly encourage further studying of irradiation arrangement of an isolated liver with epithermal neutron fields.  相似文献   
944.
Background: The analgesic nefopam does not compromise ventilation, is minimally sedating, and is effective as a treatment for postoperative shivering. The authors evaluated the effects of nefopam on the major thermoregulatory responses in humans: sweating, vasoconstriction, and shivering.

Methods: Nine volunteers were studied on three randomly assigned days: (1) control (saline), (2) nefopam at a target plasma concentration of 35 ng/ml (low dose), and (3) nefopam at a target concentration of 70 ng/ml (high dose, approximately 20 mg total). Each day, skin and core temperatures were increased to provoke sweating and then reduced to elicit peripheral vasoconstriction and shivering. The authors determined the thresholds (triggering core temperature at a designated skin temperature of 34[degrees]C) by mathematically compensating for changes in skin temperature using the established linear cutaneous contributions to control of each response.

Results: Nefopam did not significantly modify the slopes for sweating (0.0 +/- 4.9[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = 0.73 +/- 0.32) or vasoconstriction (-3.6 +/- 5.0[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = -0.47 +/- 0.41). In contrast, nefopam significantly reduced the slope of shivering (-16.8 +/- 9.3[degrees]C [middle dot] [mu]g-1 [middle dot] ml; r2 = 0.92 +/- 0.06). Therefore, high-dose nefopam reduced the shivering threshold by 0.9 +/- 0.4[degrees]C (P < 0.001) without any discernible effect on the sweating or vasoconstriction thresholds.  相似文献   

945.
OBJECTIVE: The aim of this study was to evaluate the long-term results of the Antegrade Continent Enema (ACE) procedure for treating severe constipation in adults. METHODS: Over 10 years 37 ACE conduits were created in 32 patients (median age 35 years, 26 women) with constipation caused by slow transit, obstructed defaecation or both. Conduits were created from the appendix (n = 20, 54%), ileum (n = 10, 27%), neoappendix caecostomy (n = 5, 14%) or colon (n = 2, 5%). Clinical records were retrospectively reviewed to determine outcome. RESULTS: After a median follow up of 36 (range 13-140) months, 28 (88%) required at least one further procedure on a primary conduit, including reversal in 19 (59%). Five patients had a second conduit fashioned, two successfully. Conduit type and constipation cause did not significantly influence the rates of ACE reversal or major revision. Ileal conduits were associated with fewer minor revision procedures for stenosis (1 in 7 patients) than appendix conduits (21 in 20 patients). There was one (3%) serious complication. Satisfactory ACE function was ultimately achieved in 47% of patients, at last follow up. After ACE reversal, 9 (28%) patients underwent formation of an end stoma and 3 patients had a colectomy. CONCLUSIONS: Revision procedures are common, but approximately half of patients can expect satisfactory long-term ACE function. ACE conduit reversal does not preclude subsequent alternative surgical strategies to treat this difficult condition.  相似文献   
946.
947.
Tissue equivalent proportional counter microdosimetry has been applied in the dosimetry of epithermal neutron beams as they can provide an independent and accurate method to determine gamma ray and neutron absorbed doses. Dosimetric comparison has been performed using a tissue equivalent proportional counter, dual ionisation chambers and DORT computer code at FiR 1 boron neutron capture therapy facility in Espoo, Finland. The three methods were applied to determine neutron and gamma ray absorbed doses at 25, 40, 60 and 120 mm depths along the beam centerline in a water-filled PMMA phantom. The determined absorbed doses were found to agree within the limits of the estimated uncertainties.  相似文献   
948.
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.  相似文献   
949.
INTRODUCTION: Adhesive capsulitis is a clinical entity characterized by a loss of motion and a decrease of the joint volume capacity. Results of clinical trials have shown that distensions can help to decrease pain and increase the range of motion. OBJECTIVE: The purpose of the study was to measure the effect of repeated distension arthrography combined with an intensive program of rehabilitation on pain, range of motion, and occupational outcome in patients with adhesive capsulitis. DESIGN: 39 cases of idiopathic capsulitis (7 cases) or secondary capsulitis (19 post-traumatic, 13 post-surgery of the rotator cuff) were included in the study. Intervention consisted of an intensive program of passive and active physiotherapy during one? Week and then distension arthrography, performed 3 times at 1- week intervals, with steroid injections in the glenohumeral joint and 1 in the subacromial space. RESULTS: Lateral elevation improved substantially after the first week of physiotherapy and medial rotation after the first distension. Pain intensity decreased after the first distension. After the third distension, very small changes were noted. Results did not differ by etiology of capsulitis. At the end of the program, 9 of 17 patients could return to their previous job. CONCLUSIONS: Two repeated arthrographic distensions with steroid injection and an intensive program of physiotherapy improves the range of motion and the painful condition associated with capsulitis and allows for a rapid return to employment. A third distension does not seem to provide a further benefit, as has been found by other studies.  相似文献   
950.
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