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941.
Cyclosporin A is a powerful immunosuppressive drug that has had a major impact on transplant therapy. It apparently links to different enzymatic pathways, and affects multiple enzymatic systems. Transforming growth factor beta induces the deposition of glycosaminoglycans, proteoglycans, and collagen fibers in the extracellular matrix. The aim of this study of normal and hypertrophic human gingival fibroblast cultures was to evaluate the cytoskeletal and extracellular changes in glycosaminoglycan secretion due to the presence of cyclosporin A and transforming growth factor beta. The results showed that there is an increase in total and individual classes of extracellular glycosaminoglycans in the presence of cyclosporin A and transforming growth factor beta, but the action of the latter was significantly greater. Immunohistochemical analysis of the cytoskeleton did not reveal any morphological differences between treated and control cells. Our data suggest that the biochemical changes in the extracellular matrix are caused more by cytokine, and that cyclosporin A does not induce any morphological changes in fibroblast cultures derived from hypertrophic and normal gingiva.  相似文献   
942.
943.
BACKGROUND: Recently, various studies have questioned the efficacy of intraoperative acute normovolemic hemodilution (ANH) in reducing bleeding and the need for allogeneic transfusions in cardiac surgery. The aim of the present study was to reevaluate the effects of a low-volume ANH in elective, adult open-heart surgery. METHODS: Two hundred four consecutive adult patients undergoing cardiac surgery were prospectively randomized in a nonblinded manner into two groups: ANH group (103 patients), where 5-8 ml/kg of blood was withdrawn before systemic heparinization and replaced with colloid solutions, and a control group, where no hemodilution was performed (101 patients). Procedures included single and multiple valve surgery, aortic root surgery, coronary surgery combined with valve surgery, or partial left ventriculectomy. The purpose of the study was to evaluate the efficacy of ANH in reducing the need for allogeneic blood components. Routine hematochemical evaluations, perioperative blood loss, major complications, and outcomes were also recorded. RESULTS: No differences were found between the groups regarding demographics, baseline hematochemical data, and operative characteristics. There was no difference in the amount of transfusions of packed red cells, fresh frozen plasma, platelet concentrates, total number of patients transfused (control group, 36% vs. ANH group, 34.3%; P = 0.88), and amount of postoperative bleeding (control group, 412 ml [313-552 ml] vs. ANH group, 374 ml [255-704 ml]) (median [25th-75th percentiles]); P = 0.94. Further, perioperative complications, postoperative hematochemical data, and outcomes were not different. CONCLUSIONS: In patients undergoing elective open-heart surgery, low-volume ANH showed lack of efficacy in reducing the need for allogeneic transfusions and postoperative bleeding.  相似文献   
944.
The aim of this study was to investigate modern and classical electroencephalographic (EEG) variables in response to remifentanil and propofol infusions. We hypothesized that modern EEG variables may indicate the effects of propofol but not of remifentanil. Twenty-five patients were included in the study after the end of elective spine surgery without any surgical stimulation. Baseline values were defined with remifentanil 0.3 microg. kg(-1). min(-1) and target-controlled infusion of propofol 3.0 microg/mL. EEG changes were evaluated 1, 3, 5, 7, and 9 min after the stop of remifentanil infusion, followed by a step-by-step reduction (0.2 microg/mL) every 3 min of target-controlled infusion propofol. Narcotrend (NT; classifying EEG stages from awake to deep anesthesia), bispectral index (BIS), EEG spectral frequency bands (%), 50% (Median) and 95% percentiles (spectral edge frequency), mean arterial blood pressure, heart rate, and oxygen saturation were detected at every time point. The end of remifentanil application resulted in significant increases in %alpha, spectral edge frequency, mean arterial blood pressure, and %theta and decreases in %delta (P < 0.05). NT, BIS, Median, heart rate, and oxygen saturation were unchanged. Decreases in propofol concentration were associated with statistically significant increases in NT and BIS (P < 0.05). Thus, the sedative-hypnotic component of propofol could be estimated by modern EEG variables (NT and BIS), whereas the analgesic component provided by remifentanil was not indicated. However, during conditions without surgical stimulation, neither NT nor BIS provided an adequate assessment of the depth of anesthesia when a remifentanil infusion was used. IMPLICATIONS: We investigated modern and classical electroencephalographic (EEG) variables during emergence from propofol/remifentanil anesthesia. Modern EEG variables indicate changes of infusion in propofol, but not in remifentanil. Thus, modern EEG variables did not provide an adequate assessment of depth of anesthesia when remifentanil was used.  相似文献   
945.
946.
BACKGROUND: Bilateral lung (BLTx) and heart-lung transplantation have gained wide acceptance as treatment of end-stage lung disease from cystic fibrosis. We reviewed our 13-year experience with thoracic transplantation for cystic fibrosis with an operative approach that favors use of cardiopulmonary bypass for BLTx. METHODS: Sixty-four patients with cystic fibrosis underwent heart-lung transplantation (n = 22, 34.4%) or BLTx (n = 42, 65.6%) between 1988 and 2000. Mean age and weight at transplantation were 29 +/- 8 years and 51 +/- 11 kg, respectively. Mean follow-up for survivors was 4.4 +/- 3.6 years. Immunosuppression regimen included cyclosporine, tapered corticosteroids, azathioprine, and induction therapy with OKT3 (murine monoclonal antibodies) or rabbit antithymocyte globulin. Cardiopulmonary bypass was used in all but 5 patients (7.8%). However, in 8 (19%) of the 42 patients having BLTx, only the grafting of the second lung was performed with cardiopulmonary bypass. RESULTS: The operative mortality rate was 1.6%. The actuarial survival rates at 1 year, 3 years, 5 years and 10 years were 93.2%, 77.7%, 61.8%, and 48.1%, respectively, with no significant difference between BLTx and heart-lung transplantation. The major hospital complications were pneumonia (n = 11, 17.2%) and bleeding (n = 8, 12.5%). Clinically significant reperfusion injury was observed in 6 patients, 3 of whom required reintubation. Freedom from acute lung rejection beyond 1 year was 47.7%. One patient underwent late retransplantation, and 4 required bronchial stenting. Obliterative bronchiolitis accounted for eight (50.0%) of 16 late deaths. CONCLUSIONS: Though postoperative bleeding and pneumonia are still of concern, satisfactory early and intermediate-term results can be expected in patients undergoing BLTx or heart-lung transplantation for cystic fibrosis. Cardiopulmonary bypass can be used for BLTx with no adverse impact on intermediate and long-term outcomes.  相似文献   
947.
Thorough evaluation of surgical risk represents the sine qua non for a correct therapeutic choice particularly in the elderly who are frequently affected by multiple pathologies. The aim of this study was to evaluate the prognostic value of two of the most common classification systems for predicting surgical risk (ASA and Reiss scores) and of other laboratory parameters. A consecutive series of 207 patients aged 70 or above were analysed retrospectively, considering age, ASA and Reiss scores, elective or emergency surgery, operative time, leucocytes, haemoglobin, creatinine, and albumin levels. Morbidity and mortality rates were compared in relation to these parameters. Emergency surgery was associated with significantly higher morbidity (P = 0.006 chi-square) and mortality (P = 0.001 chi-square) than elective surgery. No differences in morbidity were noted in association with the ASA classification (P = 0.07 chi-square), though there was a significant difference (P = 0.001 chi-square) in mortality. Significant differences in both morbidity (P = 0.04 chi-square) and mortality (P = 0.001 chi-square) were found to be associated with the Reiss classification. Multivariate analysis showed that ASA score (P = 0.006), Reiss score (P = 0.004), operative time (P = 0.005), and haemoglobin level (P = 0.01) were independent prognostic factors. The results of the study confirm the prognostic value of multiparametric classifications such as the ASA and Reiss score in elderly patients, even if the addition of other prognostic factors may be expected to improve the sensitivity.  相似文献   
948.
The aim of the study was to evaluate the effects of preoperative intra-arterial hepatic chemotherapy (IAHC) on the outcome of liver resections for hepatic metastases from colorectal cancer. Twelve patients (IAHC group) treated by IAHC with fluorodeoxyuridine (FUdR) and subsequent liver resection and 40 patients who underwent liver resection without preliminary IAHC (non-IAHC group) were analysed comparatively in terms of age, gender, concomitant diseases, previous abdominal surgery, type of hepatic resection, use of portal clamping, and associated surgical procedures. For the purposes of the study, length of operation, intraoperative blood losses, perioperative transfusions, length of hospitalisation, complications and mortality were also recorded. The two groups were comparable (p = n.s.) for those variables affecting the perioperative course. As regards the end points of the study, no significant differences were recorded in length of operation, intraoperative blood losses, perioperative transfusions [except for more postoperative plasma transfusions in the IAHC group (16.7% vs 5.0%, p = 0.009)] and postoperative complications (9.1% vs 17.5%, p = 0.415). Postoperative mortality consisted in one patient in the IAHC group. Postoperative hospitalization was significantly longer in the non-IAHC group (median: 8 vs 10, range: 6-13 vs 5-33 days; p = 0.004). IAHC does not negatively affect the outcome of subsequent liver resection.  相似文献   
949.
This study reports on 10 years of experience in observing diverticular disease. The study considers 77 patients, 41 males and 36 females, aged from 50 to 88 years (mean age: 70 years), observed from January 1991 to December 2001. Sixty-two patients were admitted from the Accident and Emergency Unit and 15 were elected patients. Five patients underwent emergency surgery, while 72 received only antibiotic therapy. The overall mortality rate was 0. The morbidity rate was 22% in those patients undergoing emergency surgery. In only one of the elected patients was wound suppuration detected. Diverticular disease, in most cases, is treated by antibiotic therapy alone, but in 30% of cases surgery is necessary. Colon resection and immediate anastomosis are the first choice operation also in the emergency setting, provided local conditions (inflammation, septic contamination) make anastomosis safe. In patients with major peritoneal contamination, Hartman's operation and subsequent recanalization after 6 months are to be preferred.  相似文献   
950.
Clinical diagnosis of carpal tunnel syndrome usually is easy and sensitive, but frequently, it is based on history and referred symptoms when no motor or sensory deficits are observed during examination. In patients with carpal tunnel syndrome, a dissociation between the severity of the disease reported by the patient and the deficits clinically evaluated by the physician often are observed. The Italian Carpal Tunnel Syndrome Study Group did a multicenter study on 740 patients (1123 hands) with carpal tunnel syndrome to assess the aspects of dissociation between the patient's and the physician's quantification of the disease severity and the ability of the patients with carpal tunnel syndrome to do daily activities. Validated patient-oriented parameters assessing symptoms and hand functional status were used. The relationship between the physician's and the patient's measurements is strong with a linear significant correlation when analyzing the functional status of the hand but not so clear and simple when analyzing the symptoms. Patients with mild-to-moderate carpal tunnel syndrome seemed to function well, although severe symptoms may be reported by the patient; however, when nerve impairment becomes severe, the patient's hand function is extremely impaired although symptoms may be milder. The data show that the patient's point of view is reliable. Carpal tunnel syndrome seems to be an ideal model to evaluate the importance of patient-oriented measurements.  相似文献   
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